WorldWideScience

Sample records for combined cycle cogeneration

  1. Combined cycles and cogeneration with natural gas and alternative fuels

    International Nuclear Information System (INIS)

    Gusso, R.

    1992-01-01

    Since 1985 there has been a sharp increase world-wide in the sales of gas turbines. The main reasons for this are: the improved designs allowing better gas turbine and, thus, combined cycle efficiencies; the good fuel use indices in the the case of cogeneration; the versatility of the gas turbines even with poly-fuel plants; greatly limited exhaust emissions; and lower manufacturing costs and delivery times with respect to conventional plants. This paper after a brief discussion on the evolution in gas turbine applications in the world and in Italy, assesses their use and environmental impacts with fuels other than natural gas. The paper then reviews Italian efforts to develop power plants incorporating combined cycles and the gasification of coal, residual, and other low calorific value fuels

  2. Performance and operational economics estimates for a coal gasification combined-cycle cogeneration powerplant

    Science.gov (United States)

    Nainiger, J. J.; Burns, R. K.; Easley, A. J.

    1982-01-01

    A performance and operational economics analysis is presented for an integrated-gasifier, combined-cycle (IGCC) system to meet the steam and baseload electrical requirements. The effect of time variations in steam and electrial requirements is included. The amount and timing of electricity purchases from sales to the electric utility are determined. The resulting expenses for purchased electricity and revenues from electricity sales are estimated by using an assumed utility rate structure model. Cogeneration results for a range of potential IGCC cogeneration system sizes are compared with the fuel consumption and costs of natural gas and electricity to meet requirements without cogeneration. The results indicate that an IGCC cogeneration system could save about 10 percent of the total fuel energy presently required to supply steam and electrical requirements without cogeneration. Also for the assumed future fuel and electricity prices, an annual operating cost savings of 21 percent to 26 percent could be achieved with such a cogeneration system. An analysis of the effects of electricity price, fuel price, and system availability indicates that the IGCC cogeneration system has a good potential for economical operation over a wide range in these assumptions.

  3. Conceptual design study of a coal gasification combined-cycle powerplant for industrial cogeneration

    Science.gov (United States)

    Bloomfield, H. S.; Nelson, S. G.; Straight, H. F.; Subramaniam, T. K.; Winklepleck, R. G.

    1981-01-01

    A conceptual design study was conducted to assess technical feasibility, environmental characteristics, and economics of coal gasification. The feasibility of a coal gasification combined cycle cogeneration powerplant was examined in response to energy needs and to national policy aimed at decreasing dependence on oil and natural gas. The powerplant provides the steam heating and baseload electrical requirements while serving as a prototype for industrial cogeneration and a modular building block for utility applications. The following topics are discussed: (1) screening of candidate gasification, sulfur removal and power conversion components; (2) definition of a reference system; (3) quantification of plant emissions and waste streams; (4) estimates of capital and operating costs; and (5) a procurement and construction schedule. It is concluded that the proposed powerplant is technically feasible and environmentally superior.

  4. Thermoeconomic analysis of Biomass Integrated Gasification Gas Turbine Combined Cycle (BIG GT CC) cogeneration plant

    Energy Technology Data Exchange (ETDEWEB)

    Arrieta, Felipe Raul Ponce; Lora, Electo Silva [Escola Federal de Engenharia de Itajuba, MG (Brazil). Nucleo de Estudos de Sistemas Termicos]. E-mails: aponce@iem.efei.br; electo@iem.efei.br; Perez, Silvia Azucena Nebra de [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Energia]. E-mail: sanebra@fem. unicamp.br

    2000-07-01

    Using thermoeconomics as a tool to identify the location and magnitude of the real thermodynamic losses (energy waste, or exergy destruction and exergy losses) it is possible to assess the production costs of each product (electric power and heat) and the exergetic and exergoeconomic cost of each flow in a cogeneration plant to assist in decision-marketing procedures concerning to plant design, investment, operation and allocations of research funds. Thermo economic analysis of Biomass Integrated Gasification Gas Turbine Combined Cycle (BIG GT CC) cogeneration plant for its applications in sugar cane mills brings the following results: the global exergetic efficiency is low; the highest irreversibilities occur in the following equipment, by order: scrubber (38%), gas turbine (16%), dryer (12%), gasifier and HRSG (6%); due to the adopted cost distribution methodology, the unit exergetic cost of the heat (4,11) is lower than electricity (4,71); the lower market price of biomass is one of the most sensible parameter in the possible implementation of BIG-GT technology in sugar cane industry; the production costs are 31 US$/MWh and 32 US$/MWh for electricity and heat, respectively. The electricity cost is, after all, competitive with the actual market price. The electricity and heat costs are lower or almost equal than other values reported for actual Rankine cycle cogeneration plants. (author)

  5. 'BACO' code: Cogeneration cycles heat balance

    International Nuclear Information System (INIS)

    Huelamo Martinez, E.; Conesa Lopez, P.; Garcia Kilroy, P.

    1993-01-01

    This paper presents a code, developed by Empresarios Agrupados, sponsored by OCIDE, CSE and ENHER, that, with Electrical Utilities as final users, allows to make combined and cogeneration cycles technical-economical studies. (author)

  6. Analysis of an electricity–cooling cogeneration system based on RC–ARS combined cycle aboard ship

    International Nuclear Information System (INIS)

    Liang, Youcai; Shu, Gequn; Tian, Hua; Liang, Xingyu; Wei, Haiqiao; Liu, Lina

    2013-01-01

    Highlights: • A novel electricity–cooling cogeneration system was used to recover waste heat aboard ships. • Performance of such RC–ARS system was investigated theoretically. • Optimal exergy output can be obtained when the vaporization pressure of RC is 300 kPa. • The exergy efficiency of cogeneration system is 5–12% higher than that of basic Rankine cycle only. - Abstract: In this paper, an electricity–cooling cogeneration system based on Rankine–absorption refrigeration combined cycle is proposed to recover the waste heat of the engine coolant and exhaust gas to generate electricity and cooling onboard ships. Water is selected as the working fluid of the Rankine cycle (RC), and a binary solution of ammonia–water is used as the working fluid of the absorption refrigeration cycle. The working fluid of RC is preheated by the engine coolant and then evaporated and superheated by the exhaust gas. The absorption cycle is powered by the heat of steam at the turbine outlet. Electricity output, cooling capacity, total exergy output, primary energy ratio (PER) and exergy efficiency are chosen as the objective functions. Results show that the amount of additional cooling output is up to 18 MW. Exergy output reaches the maximum 4.65 MW at the vaporization pressure of 300 kPa. The study reveals that the electricity–cooling cogeneration system has improved the exergy efficiency significantly: 5–12% increase compared with the basic Rankine cycle only. Primary energy ratio (PER) decreases as the vaporization pressure increases, varying from 0.47 to 0.40

  7. Performance analysis of a combined organic Rankine cycle and vapor compression cycle for power and refrigeration cogeneration

    International Nuclear Information System (INIS)

    Kim, Kyoung Hoon; Perez-Blanco, Horacio

    2015-01-01

    A thermodynamic analysis of cogeneration of power and refrigeration activated by low-grade sensible energy is presented in this work. An organic Rankine cycle (ORC) for power production and a vapor compression cycle (VCC) for refrigeration using the same working fluid are linked in the analysis, including the limiting case of cold production without net electricity production. We investigate the effects of key parameters on system performance such as net power production, refrigeration, and thermal and exergy efficiencies. Characteristic indexes proportional to the cost of heat exchangers or of turbines, such as total number of transfer units (NTU tot ), size parameter (SP) and isentropic volumetric flow ratio (VFR) are also examined. Three important system parameters are selected, namely turbine inlet temperature, turbine inlet pressure, and the flow division ratio. The analysis is conducted for several different working fluids. For a few special cases, isobutane is used for a sensitivity analysis due to its relatively high efficiencies. Our results show that the system has the potential to effectively use low grade thermal sources. System performance depends both on the adopted parameters and working fluid. - Highlights: • Waste heat utilization can reduce emissions of carbon dioxide. • The ORC/VCC cycle can deliver power and/or refrigeration using waste heat. • Efficiencies and size parameters are used for cycle evaluation. • The cycle performance is studied for eight suitable refrigerants. Isobutane is used for a sensitivity analysis. • The work shows that the isobutene cycle is quite promising.

  8. Cogeneration

    International Nuclear Information System (INIS)

    Derbentli, Taner

    2006-01-01

    may be done in universities and industry which may serve this purpose. Some of these studies are discussed below. The feasibility studies for cogeneration plants is a field which should be developed.. The hourly, daily, monthly and yearly power and heat demands should be calculated to decide on the correct capacity of the plant. The capacity of the plant may be decided on the electrical power demand or the heat demand. In general it is more economical to base the plant capacity on the electrical power demand. In order to save as much energy as possible, the plant should operate continuously at full load. A study which will survey the cogeneration plants in service today, to determine the annual average fuel utilization efficiency may be a useful guide in sizing new cogeneration plants. It is important to select and size the equipment forming the cogeneration plant so that the sum of the operating and investment costs are minimized. The methodology used for this purpose is called ex ergo economic analysis which is based on the pioneering works of Tsatsaronis, El Sayed and Valero. The use of cogeneration in conjunction with district heating is widely used in northern and eastern Europe. This may well be applied to newly developing residential areas, university campuses and similar complexes. The main obstacle in the application of combined power and district heating is high initial investment costs.Government policies and subsidies in this area may be well worth because of the national savings resulting from the reduction in fuel imports. Micro cogeneration or spread electric power production is becoming more feasible as the technology developers and costs are reduced. The costs of micro cogeneration technologies, such as micro turbines, fuel cells, Stirling cycle engines are starting to become competitive with conventional technologies which cost approximately 500 US dollars per kw today. Another area where research is needed is the use of fuels other than natural gas

  9. Optimisation of environmental gas cleaning routes for solid wastes cogeneration systems. Part II - Analysis of waste incineration combined gas/steam cycle

    International Nuclear Information System (INIS)

    Holanda, Marcelo R.; Perrella Balestieri, Jose A.

    2008-01-01

    In the first paper of this paper (Part I), conditions were presented for the gas cleaning technological route for environomic optimisation of a cogeneration system based in a thermal cycle with municipal solid waste incineration. In this second part, an environomic analysis is presented of a cogeneration system comprising a combined cycle composed of a gas cycle burning natural gas with a heat recovery steam generator with no supplementary burning and a steam cycle burning municipal solid wastes (MSW) to which will be added a pure back pressure steam turbine (another one) of pure condensation. This analysis aims to select, concerning some scenarios, the best atmospheric pollutant emission control routes (rc) according to the investment cost minimisation, operation and social damage criteria. In this study, a comparison is also performed with the results obtained in the Case Study presented in Part I

  10. An object-oriented computational model for combined cycle cogeneration analysis; Um modelo computacional para analise de ciclos combinados para projetos de sistemas de cogeracao

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Alexandre M. da; Balestieri, Jose A.P.; Magalhaes Filho, Paulo [UNESP, Guaratingueta, SP (Brazil). Escola de Engenharia. Dept. de Energia]. E-mails: amarcial@uol.com.br; perella@feg.unesp.br; pfilho@feg.unesp.br

    2000-07-01

    This paper presents the use of computational resources in a simulation procedure to predict the performance of combined cycle cogeneration systems in which energetic analysis is used in the modeling. Thermal demand of a consuming process are used as the main entrance data and, associated to the performance characteristics of each component of the system, it is evaluated the influence of some parameters of the system such as thermal efficiency and global efficiency. The computational language is Visual Basic for Applications associated to an electronic sheet. Two combined cycle cogeneration schemes are pre-defined: one is composed of a gas turbine, heat recovery steam generator and a back pressure steam turbine with one extraction, in which both are connected to the different pressure level process plant; the other scheme has a difference a two extraction-condensing steam turbine instead of the back pressure one. Some illustrative graphics are generated for allowing comparison of the appraised systems. The strategy of the system simulation is obtained by carefully linking the information of various components according to the flow diagrams. (author)

  11. Energetic and exergetic analysis of cogeneration power combined cycle and ME-TVC-MED water desalination plant: Part-1 operation and performance

    International Nuclear Information System (INIS)

    Almutairi, Abdulrahman; Pilidis, Pericles; Al-Mutawa, Nawaf; Al-Weshahi, Mohammed

    2016-01-01

    Highlights: • Develop a comprehensive model for a very advanced cogeneration plant using real data. • Evaluate ME-TVC-MED unit using the latest thermodynamic properties of seawater. • Evaluate the desalination unit contribution to the overall efficiency. • Evaluate the stage exergetic efficiency in the ME-TVC-MED unit. • Numerous possibilities have been suggested to improve the proposed system. - Abstract: A comprehensive model of cogeneration plant for electrical power and water desalination has been developed based on energetic and exergetic analyses using real operational data. The power side is a combined cycle power plant (CCPP), while the desalination side is a multi-effect thermal vapour compression plant coupled with a conventional multi-effect plant (ME-TVC-MED). IPSEpro software was utilized to model the process, which shows good agreement with the manufacturer's data and published research. The thermodynamic properties of saline water were obtained from the latest published data in the literature. The performance of the cogeneration plant was examined for different ambient temperatures, pressure ratios, loads, feed water temperatures, number of effects and entrainment ratios. The results show that gas turbine engines produce the highest level of useful work in the system at around 34% of the total fuel input. At the same time, they constitute a major source of irreversibility, which accounts for 84% of the total exergy destruction in the plant, while the lowest source of irreversibility is in the steam turbine of 3.3% due to the type of working fluid and reheating system. In the ME-TVC-MED desalination unit, the highest source of irreversibilities occurs in the effects and in the thermo-compressor. The first two effects in the ME-TVC parallel section were responsible for about 40.6% of the total effect exergy destruction, which constitutes the highest value among all the effects. Operating the system at full load while reducing ambient

  12. Fossil fuel savings, carbon emission reduction and economic attractiveness of medium-scale integrated biomass gasification combined cycle cogeneration plants

    Directory of Open Access Journals (Sweden)

    Kalina Jacek

    2012-01-01

    Full Text Available The paper theoretically investigates the system made up of fluidized bed gasifier, SGT-100 gas turbine and bottoming steam cycle. Different configurations of the combined cycle plant are examined. A comparison is made between systems with producer gas (PG and natural gas (NG fired turbine. Supplementary firing of the PG in a heat recovery steam generator is also taken into account. The performance of the gas turbine is investigated using in-house built Engineering Equation Solver model. Steam cycle is modeled using GateCycleTM simulation software. The results are compared in terms of electric energy generation efficiency, CO2 emission and fossil fuel energy savings. Finally there is performed an economic analysis of a sample project. The results show relatively good performance in the both alternative configurations at different rates of supplementary firing. Furthermore, positive values of economic indices were obtained. [Acknowledgements. This work was carried out within the frame of research project no. N N513 004036, titled: Analysis and optimization of distributed energy conversion plants integrated with gasification of biomass. The project is financed by the Polish Ministry of Science.

  13. 'BACO' code: Cogeneration cycles heat balance; El programa BACO (Balance de Ciclos de Cogeneracion)

    Energy Technology Data Exchange (ETDEWEB)

    Huelamo Martinez, E; Conesa Lopez, P; Garcia Kilroy, P [Empresarios Agrupados, A.I.E., Madrid (Spain)

    1993-12-15

    This paper presents a code, developed by Empresarios Agrupados, sponsored by OCIDE, CSE and ENHER, that, with Electrical Utilities as final users, allows to make combined and cogeneration cycles technical-economical studies. (author)

  14. HTGR-steam cycle/cogeneration plant economic potential

    International Nuclear Information System (INIS)

    1981-05-01

    The cogeneration of heat and electricity provides the potential for improved fuel utilization and corresponding reductions in energy costs. In the evaluation of the cogeneration plant product costs, it is advantageous to develop joint-product cost curves for alternative cogeneration plant models. The advantages and incentives for cogeneration are then presented in a form most useful to evaluate the various energy options. The HTGR-Steam Cycle/Cogeneration (SC/C) system is envisioned to have strong cogeneration potential due to its high-quality steam capability, its perceived nuclear siting advantages, and its projected cost advantages relative to coal. The economic information presented is based upon capital costs developed during 1980 and the economic assumptions identified herein

  15. HTGR-GT closed-cycle gas turbine: a plant concept with inherent cogeneration (power plus heat production) capability

    International Nuclear Information System (INIS)

    McDonald, C.F.

    1980-04-01

    The high-grade sensible heat rejection characteristic of the high-temperature gas-cooled reactor-gas turbine (HTGR-GT) plant is ideally suited to cogeneration. Cogeneration in this nuclear closed-cycle plant could include (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. This paper discusses the HTGR-GT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes. This paper concludes that the HTGR-GT plant, which can potentially approach a 50% overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation

  16. Effect of cycle coupling-configuration on energy cascade utilization for a new power and cooling cogeneration cycle

    International Nuclear Information System (INIS)

    Jing, Xuye; Zheng, Danxing

    2014-01-01

    Highlights: • A new power and cooling cogeneration cycle was proposed. • The thermophysical properties and the performance of the new cycle were calculated. • Different cycle coupling-configurations were analyzed. • The energy efficiency boosting mechanism of the new cycle was elucidated. - Abstract: To recover mid-low grade heat, a new power/cooling cogeneration cycle was proposed by combining the Kalina cycle and the double-effect ammonia–water absorption refrigeration (DAAR) cycle together, and the equivalent heat-to-power and exergy efficiencies of the cogeneration cycle reached 41.18% and 58.00%, respectively. To determine the effect of cycle coupling-configuration on energy cascade utilization for the new cycle, the cycle coupling-configuration of the Kalina and DAAR cycles were first analyzed, after which the cycle coupling-configuration of the new cycle was analyzed. Analysis results showed that the cycle coupling-configuration of the new cycle enhanced the energy cascade utilization. Furthermore, the energy efficiency boosting mechanism of the new cycle was elucidated

  17. Cogeneration cycles applied to desalination in the Arab World: state of the art

    International Nuclear Information System (INIS)

    Yassin, Jamal Saleh

    2006-01-01

    This paper presents a review of cogeneration cycles applied to water desalination in most of the Arab countries. The scarcity of fresh water resources in many countries around the world, and in particular Gulf countries and north African countries such as Libya and Tunisia forced the local authorities to establish many desalination plants to compensate the water shortage. Some plants are conventional for desalination processes only and others are with cogeneration cycle. The high performance of cogeneration cycles encouraged establishing combined power and desalination plants. The present study is intended to provide an overview of cogeneration cycles in conjunction with desalination technologies under the two main resources of energy, fossils and renewables. Thermal technologies, which utilize fossil resource constitute the mainstay of large-scale desalination in the Arab countries and enjoy a relatively important position worldwide. While the technologies which utilize renewable resources such as solar are getting more attention year by year and still under research and almost for small units.(Author)

  18. Cogeneration

    International Nuclear Information System (INIS)

    Lock, R.H.J.H.

    1990-01-01

    Cogeneration has dominated generation capacity expansion in the 1980s in many regions in a way that was never envisaged in the 1970s. The author of this paper suspects it will continue to play a major role in the 1990s in providing new power supply, though perhaps as a smaller part of a larger and more diverse market to meet new capacity needs than we have seen in the 1980s. When Congress enacted Section 210 of PURPA in 1978, its central goal was to create, through a series of regulatory protections primarily designed to neutralize the monopsony power of the purchasing utility, a quasi-market for cogeneration and certain other small power technologies. This would provide a truer test of their value in the power supply mix than had traditional regulation. However, Congress envisaged these sources as only a small, though potentially efficient, adjunct to traditional utility capacity additions

  19. Co-generation project for the Combined Cycle Power Plant President Juarez Rosarito and a reverse osmosis desalting plant; Proyecto de cogeneracion para la planta de ciclo combinado Presidente Juarez Rosarito y una planta desaladora de osmosis inversa

    Energy Technology Data Exchange (ETDEWEB)

    Beltran Mora, Hector; Espindola Hernandez, Salvador [Universidad NAcional Autonoma de Mexico (UNAM), Mexico, D.F. (Mexico)

    2006-11-15

    In this work a technical and economical analysis of the installation of a reverse osmosis desalting plant connected to a power station that uses the combined cycle technology under a co-generation scheme is presented: production of electricity and water. The operation program of the desalting power station will be determined by the demand of energy of the combined cycle power station; the proposal is that the desalting plant operates in the hours of low load of the power station and shuts down at the peak hours of electrical energy demand. So that this study is representative, the demand curves of electric energy of the units of combined cycle of Central President Juarez Rosarito of the Comision Federal de Electricidad (CFE) have been taken and updated the data of the reverse osmosis desalting plants that are available at the moment in the market. As basis of the study the level costs will be determined so much as the electrical energy generated by the power station of combined cycle, operating inside and outside of a co-generation scheme and the costs made level for the water produced by the reverse osmosis plant under two assumptions: the first one is buying the electrical energy from CFE and the second one considering that the CFE is the owner of the desalting plant and therefore the cost of electrical energy to desalting the plant is zero. This work shows the economic impacts on the costs of the generation of electrical energy and on those of the desalted water in a co-generation scheme. The results shown in this study can be considered for the future planning in the construction of desalting plants to supply of water in the Northwestern zones of the country where serious problems of water shortage exist. [Spanish] En este trabajo se presenta un analisis tecnico y economico de la instalacion de una planta desaladora de osmosis inversa acoplada a una central de generacion de energia electrica que utiliza la tecnologia de ciclo combinado bajo un esquema de

  20. High-temperature gas-cooled reactor steam cycle/cogeneration application study update

    International Nuclear Information System (INIS)

    1981-09-01

    Since publication of a report on the application of a High Temperature Gas-Cooled Reactor Steam Cycle/Cogeneration (HTGR-SC/C) plant in December of 1980, progress has continued on application related activities. In particular, a reference plant and an application identification effort has been performed, a variable cogeneration cycle balance-of-plant design was developed and an updated economic analysis was prepared. A reference HTGR-SC/C plant size of 2240 MW(t) was selected, primarily on the basis of 2240 MW(t) being in the mid-range of anticipated application needs and the availability of the design data from the 2240 MW(t) Steam Cycle/Electric generation plant design. A variable cogeneration cycle plant design was developed having the capability of operating at a range of process steam loads between the reference design load (full cogeneration) and the no process steam load condition

  1. A proposal to define when combined cycle can be classified as a cogeneration plants; Proposta di definizione di impianto di cogenerazione a ciclo combinato

    Energy Technology Data Exchange (ETDEWEB)

    Macchi, E. [Milan Politecnico, Milan (Italy)

    1999-09-01

    The recent decree on liberalization of the Italian electric market assigns to the authority for electric energy and natural gas the task of defining under which conditions a combined heat and power plant (CHP) obtains a significant primary energy saving when compared to separate productions. The present paper outlines and discusses the proposal made by a working group of CTI (Italian thermo-technical committee). The most significant features of the proposal are the following: i the use of IRE (Energy saving index), based upon net, annual energy production, certified by independent institutions; ii the adoption of an automatic procedure of yearly updating the reference performance related to conventional power generation, accounting for technology evolution; iii the assumption of a lower limit for the thermal/fuel energy ratio and iv correction procedures in case of usage of non-conventional fuels (municipal wastes, process gases, etc.) [Italian] Il recente decreto sulla liberalizzazione del mercato elettrico prevede che l'autorita per l'energie elettrica e il gas definisca le condizioni per cui un impianto di produzione combinata di energia elettrica e calore garantisce un significativo risparmio di energia rispetto alle produzioni separate. Nella presente nota viene descritta e commentata una proposta operativa avanzata da un gruppo di lavoro del Comitato Termotecnico Italiano (CTI). Elementi caratterizzanti la proposta sono: i) il riferimento all'indice IRE (indice di Risparmio di Energia primaria), valutato su prestazioni annue nette, a consuntivo e certificate da Enti indipendenti, ii) l'introduzione di un meccanismo automatico di revisione annuale di parametri di confronto relativi alla generazione separata che tenga conto dell'evoluzione tecnologica, iii) l'introduzione di un limite inferiore al rapporto fra la generazione di energia termica utile e l'energia introdotta con il combustibile e iv l'inserimento di

  2. Development of miller cycle gas engine for cogeneration; Developpement d'un moteur a gaz a cycle de Miller destine a la cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Tsukida, N; Sakakura, A; Murata, Y; Okamoto, K [Tokyo Gas CO., LTD (Japan); Abe, T; Takemoto, T [YANMAR Diesel Engine CO., LTD (Japan)

    2000-07-01

    We have developed a 300 kW gas engine cogeneration system for practical use that uses natural gas. Using a gas engine operated under conditions with an excess air ratio {lambda} = 1 that is able to use a three way catalyst to purify the exhaust gases, we were able to achieve high efficiency through the application of the Miller Cycle, as well as a low NO{sub X} output. In terms of product specifications, we were able to achieve an electrical efficiency of 34.2% and a heat recovery efficiency of 49.3%, making an overall efficiency of 83.5% as a cogeneration system. (authors)

  3. Exergy and exergoeconomic analyses of a supercritical CO_2 cycle for a cogeneration application

    International Nuclear Information System (INIS)

    Wang, Xurong; Yang, Yi; Zheng, Ya; Dai, Yiping

    2017-01-01

    Detailed exergy and exergoeconomic analyses are performed for a combined cogeneration cycle in which the waste heat from a recompression supercritical CO_2 Brayton cycle (sCO_2) is recovered by a transcritical CO_2 cycle (tCO_2) for generating electricity. Thermodynamic and exergoeconomic models are developed on the basis of mass and energy conservations, exergy balance and exergy cost equations. Parametric investigations are then conducted to evaluate the influence of key decision variables on the sCO_2/tCO_2 performance. Finally, the combined cycle is optimized from the viewpoint of exergoeconomics. It is found that, combining the sCO_2 with a tCO_2 cycle not only enhances the energy and exergy efficiencies of the sCO_2, but also improves the cycle exergoeconomic performance. The results show that the most exergy destruction rate takes place in the reactor, and the components of the tCO_2 bottoming cycle have less exergy destruction. When the optimization is conducted based on the exergoeconomics, the overall exergoeconomic factor, the total cost rate and the exergy destruction cost rate are 53.52%, 11243.15 $/h and 5225.17 $/h, respectively. The optimization study reveals that an increase in reactor outlet temperature leads to a decrease in total cost rate and total exergy destruction cost rate of the system. - Highlights: • Exergy and exergoeconomic analyses of a combined sCO_2/tCO_2 cycle were performed. • Exergoeconomic optimization of the sCO_2/tCO_2 cycle was presented. • The reactor had the highest exergy loss among sCO_2/tCO_2 cycle components. • The overall exergoeconomic factor was up to 53.5% for the optimum case.

  4. Life cycle energy use and GHG emission assessment of coal-based SNG and power cogeneration technology in China

    International Nuclear Information System (INIS)

    Li, Sheng; Gao, Lin; Jin, Hongguang

    2016-01-01

    Highlights: • Life cycle energy use and GHG emissions are assessed for SNG and power cogeneration. • A model based on a Chinese domestic database is developed for evaluation. • Cogeneration shows lower GHG emissions than coal-power pathway. • Cogeneration has lower life cycle energy use than supercritical coal-power pathway. • Cogeneration is a good option to implement China’s clean coal technologies. - Abstract: Life cycle energy use and GHG emissions are assessed for coal-based synthetic natural gas (SNG) and power cogeneration/polygenereation (PG) technology and its competitive alternatives. Four main SNG applications are considered, including electricity generation, steam production, SNG vehicle and battery electric vehicle (BEV). Analyses show that if SNG is produced from a single product plant, the lower limits of its life cycle energy use and GHG emissions can be comparable to the average levels of coal-power and coal-BEV pathways, but are still higher than supercritical and ultra supercritical (USC) coal-power and coal-BEV pathways. If SNG is coproduced from a PG plant, when it is used for power generation, steam production, and driving BEV car, the life cycle energy uses for PG based pathways are typically lower than supercritical coal-power pathways, but are still 1.6–2.4% higher than USC coal-power pathways, and the average life cycle GHG emissions are lower than those of all coal-power pathways including USC units. If SNG is used to drive vehicle car, the life cycle energy use and GHG emissions of PG-SNGV-power pathway are both much higher than all combined coal-BEV and coal-power pathways, due to much higher energy consumption in a SNG driven car than in a BEV car. The coal-based SNG and power cogeneration technology shows comparable or better energy and environmental performances when compared to other coal-based alternatives, and is a good option to implement China’s clean coal technologies.

  5. Economic evaluation of externally fired gas turbine cycles for small-scale biomass cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Anheden, Marie [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2001-01-01

    In this conceptual study, externally fired gas turbine (EFGT) cycles in combination with a biomass-fueled, atmospheric circulating fluidized bed (CFB) furnace are investigated for small scale heat and power production ({approx} 8 MW fuel input). Three cycle configurations are considered: closed cycle, with nitrogen, helium, and a helium/carbon dioxide mixture as working fluids; open cycle operating in parallel to the CFB system; and open cycle with a series connection to the CFB system. Intercooling, postcooling, and recuperation are employed with the goal of maximizing efficiency. Aside from a thermodynamic performance analysis, the study includes an economic analysis of both the closed and open externally fired gas turbine configurations, and comparisons are made with existing and emerging alternatives for small-scale biomass cogeneration. Simulation results show that thermodynamic performance varies slightly between the different configurations and working fluids, with electrical efficiencies of 31-38% (LHV) and total efficiency of 85-106% (LHV). The economic evaluation shows that the turbomachinery and the CFB furnace dominate the total plant cost, with each contributing about 1/3 of the total installed equipment cost. The specific capital cost for installation in Sweden in 1998 currency is calculated as 26-31 kSEK/kW{sub e} which is equivalent to 3 200-3 900 USD/kW{sub e} or 2 700-3 300 EUR/kW{sub e} .The cost of electricity, COE, is estimated to 590-670 SEK/MWh{sub e} (equivalent to 73-84 USD/MWh{sub e} or 62-71 EUR/MWh{sub e}) for 4 000 full load hours per year in a cogeneration application. Comparing the economic results for the externally fired gas turbine cycles in a slightly larger scale (40-50 MW{sub f}) to the economics of conventional biomass fired steam turbine cycles shows that the cost of electricity for the two plant configurations are roughly the same with a COE of 300-350 SEK/MWh{sub e}. It is believed that the economic performance of the EFGT

  6. Investigation on an innovative cascading cycle for power and refrigeration cogeneration

    International Nuclear Information System (INIS)

    Jiang, Long; Lu, Huitong; Wang, Ruzhu; Wang, Liwei; Gong, Lixia; Lu, Yiji; Roskilly, Anthony Paul

    2017-01-01

    Highlights: • A novel cascading cycle for power and refrigeration cogeneration is proposed and investigated. • Pumpless ORC and sorption refrigeration cycle act as the first and second stage. • The highest power and refrigeration output are able to reach 232 W and 4.94 kW, respectively. • The exergy efficiency of heat utilization ranges from 30.1% to 41.8%. - Abstract: In order to further realize efficient utilization of low grade heat, an innovative cascading cycle for power and refrigeration cogeneration is proposed. Pumpless Organic Rankine Cycle (ORC) acts as the first stage, and the refrigerant R245fa is selected as the working fluid. Sorption refrigeration cycle serves as the second stage in which silica-gel/LiCl composite sorbent is developed for the improved sorption characteristic. The concerning experimental system is established, and different hot water inlet temperatures from 75 °C to 95 °C are adopted to investigate the cogeneration performance. It is indicated that the highest power and refrigeration output are able to reach 232 W and 4.94 kW, respectively under the condition of 95 °C hot water inlet temperature, 25 °C cooling water temperature and 10 °C chilled water outlet temperature. For different working conditions, the total energy and exergy efficiency of the cascading system range from 0.236 to 0.277 and 0.101 to 0.132, respectively. For cascading system the exergy efficiency of heat utilization ranges from 30.1% to 41.8%, which is 144% and 60% higher than that of pumpless ORC and sorption chiller when the hot water inlet temperature is 95 °C.

  7. Viability analysis of electric energy cogeneration in combined cycle with sugar-cane biomass gasification and natural gas; Analise de viabilidade da cogeracao de energia eletrica em ciclo combinado com gaseificacao de biomassa de cana-de-acucar e gas natural

    Energy Technology Data Exchange (ETDEWEB)

    Correa Neto, Vicente

    2001-03-15

    The objective of this thesis is evaluate the technical and economic viability of electric energy generation projects using as fuel the biomass produced in the sugar cane Brazilian industry, specifically the cane trash, the straw and the leaves of the plant, as complemental option to the expansion of the Brazilian electric system, hour in phase of deep modification in the institutional scenery, through the sale of electric energy for direct consumers or utilities, characterizing the business possibilities for the ethanol distilleries already integrated into the energy reality of the country. The analyzed technology is thermoelectric generation with combined cycle, operating in cogeneration, integrated to biomass gasification systems for the production of combustible gas, with and without addition of natural gas. The considered technology is known by the acronym BIG/GTCC, originated in Biomass Integrate Gasification Combined Cycle Gas Turbine. The economic analysis is made herself through a modeling and construction of economy project curves based on the prices of the electric energy, of the natural gas and in the costs of the retired biomass in an mechanized way.(author)

  8. A comparative thermodynamic analysis of ORC and Kalina cycles for waste heat recovery: A case study for CGAM cogeneration system

    Directory of Open Access Journals (Sweden)

    Arash Nemati

    2017-03-01

    Full Text Available A thermodynamic modeling and optimization is carried out to compare the advantages and disadvantages of organic Rankine cycle (ORC and Kalina cycle (KC as a bottoming cycle for waste heat recovery from CGAM cogeneration system. Thermodynamic models for combined CGAM/ORC and CGAM/KC systems are performed and the effects of some decision variables on the energy and exergy efficiency and turbine size parameter of the combined systems are investigated. Solving simulation equations and optimization process have been done using direct search method by EES software. It is observed that at the optimum pressure ratio of air compressor, produced power of bottoming cycles has minimum values. Also, evaporator pressure optimizes the performance of cycle, but this optimum pressure level in ORC (11 bar is much lower than that of Kalina (46 bar. In addition, ORC's simpler configuration, higher net produced power and superheated turbine outlet flow, which leads to a reliable performance for turbine, are other advantages of ORC. Kalina turbine size parameter is lower than that of the ORC which is a positive aspect of Kalina cycle. However, by a comprehensive comparison between Kalina and ORC, it is concluded that the ORC has significant privileges for waste heat recovery in this case.

  9. Life cycle inventories for bioenergy and fossil-fuel fired cogeneration plants

    International Nuclear Information System (INIS)

    Braennstroem-Norberg, B.M.; Dethlefsen, U.

    1998-06-01

    Life-cycle inventories for heat production from forest fuel, Salix, coal and oil are presented. Data from the Oerebro cogeneration plant are used for the bioenergy and coal cycles, whereas the oil-fired cycle is based on a fictive plant producing 53 MW electricity and 106 MW heat, also located in the town of Oerebro. This life cycle analysis only covers the inventory stage. A complete life cycle analysis also includes an environmental impact assessment. The methods for assessing environmental impact are still being developed and thus this phase has been omitted here. The intention is, instead, to provide an overall perspective of where in the chain the greatest environmental load for each fuel can be found. Production and energy conversion of fuel requires energy, which is often obtained from fossil fuel. This input energy corresponds to about 11% of the extracted amount of energy for oil, 9% for coal, 6% for Salix, whereas it is about 4% for forest fuel. Utilization of fossil fuel in the coal cycle amounts to production of electricity using coal condensation intended for train transports within Poland. In a life cycle perspective, biofuels show 20-30 times lower emissions of greenhouse gases in comparison with fossil fuels. The chains for biofuels also give considerably lower SO 2 emissions than the chains for coal and oil. The coal chain shows about 50% higher NO x emission than the other fuels. Finally, the study illustrates that emission of particles are similar for all sources of energy. The biofuel cycle is assessed to be generally applicable to plants of similar type and size and with similar transport distances. The oil cycle is probably applicable to small-scale cogeneration plants. However, at present there are no cogeneration plants in Sweden that are solely fired with oil. In the case of the coal cycle, deep mining and a relatively long transport distance within Poland have been assumed. If the coal mining had been from open-cast mines, and if the

  10. local alternative sources for cogeneration combined heat and power system

    Science.gov (United States)

    Agll, Abdulhakim Amer

    Global demand for energy continues to grow while countries around the globe race to reduce their reliance on fossil fuels and greenhouse gas emissions by implementing policy measures and advancing technology. Sustainability has become an important issue in transportation and infrastructure development projects. While several agencies are trying to incorporate a range of sustainability measures in their goals and missions, only a few planning agencies have been able to implement these policies and they are far from perfect. The low rate of success in implementing sustainable policies is primarily due to incomplete understanding of the system and the interaction between various elements of the system. The conventional planning efforts focuses mainly on performance measures pertaining to the system and its impact on the environment but seldom on the social and economic impacts. The objective of this study is to use clean and alternative energy can be produced from many sources, and even use existing materials for energy generation. One such pathway is using wastewater, animal and organic waste, or landfills to create biogas for energy production. There are three tasks for this study. In topic one evaluated the energy saving that produced from combined hydrogen, heat, and power and mitigate greenhouse gas emissions by using local sustainable energy at the Missouri S&T campus to reduce energy consumption and fossil fuel usage. Second topic aimed to estimate energy recovery and power generation from alternative energy source by using Rankin steam cycle from municipal solid waste at Benghazi-Libya. And the last task is in progress. The results for topics one and two have been presented.

  11. Power and cogeneration technology environomic performance typification in the context of CO2 abatement part II: Combined heat and power cogeneration

    International Nuclear Information System (INIS)

    Li, Hongtao; Marechal, Francois; Favrat, Daniel

    2010-01-01

    This is the second of a series of two articles, dealing with a new approach of environomic (thermodynamic, economic and environmental) performance 'Typification' and optimization of power generation technologies. This part treats specifically of combined heat and power (CHP) cogeneration technologies in the context of CO 2 abatement and provides a methodology for a flexible and fast project based CHP system design evaluation. One of the aspect of the approach is the post-optimization integration of the operating and capital costs, in order to effectively deal with the uncertainty of the project specific design and operation conditions (fuel, electricity and heat selling prices, project financial conditions such as investment amortization periods, annual operating hours, etc). In addition the approach also allows to efficiently evaluate the influence of the external cost such as the CO 2 tax level under a tax scheme or the CO 2 permit price in the emission trading market. Application examples, including gas turbine and combined cycles are treated with the proposed methodology, by using superstructure based generic environomic models and a multi-objective optimizer.

  12. Thermodynamic and economic studies of two new high efficient power-cooling cogeneration systems based on Kalina and absorption refrigeration cycles

    International Nuclear Information System (INIS)

    Rashidi, Jouan; Ifaei, Pouya; Esfahani, Iman Janghorban; Ataei, Abtin; Yoo, Chang Kyoo

    2016-01-01

    Highlights: • Proposing two new power and cooling cogeneration systems based on absorption chillers and Kalina cycles. • Model-based comparison through thermodynamic and economic standpoints. • Investigating sensitivity of system performance and costs to the key parameters. • Reducing total annual costs of the base system up to 8% by cogeneration. • Increasing thermal efficiency up to 4.9% despite of cooling generation. - Abstract: Two new power and cooling cogeneration systems based on Kalina cycle (KC) and absorption refrigeration cycle (AC) are proposed and studied from thermodynamic and economic viewpoints. The first proposed system, Kalina power-cooling cycle (KPCC), combines the refrigerant loop of the water-ammonia absorption chiller, consisting of an evaporator and two throttling valves with the KC. A portion of the KC mass flow enters the evaporator to generate cooling after being condensed in the KPCC system. KPCC is a flexible system adapting power and cooling cogeneration to the demand. The second proposed system, Kalina lithium bromide absorption chiller cycle (KLACC), consists of the KC and a single effect lithium bromide-water absorption chiller (AC_L_i_B_r_-_w_a_t_e_r). The KC subsystem discharges heat to the AC_L_i_B_r_-_w_a_t_e_r desorber before condensing in the condenser. The performance and economic aspects of both proposed systems are analyzed and compared with the stand alone KC. A parametric analysis is conducted to evaluate the sensitivity of efficiencies and the generated power and cooling quantities to the key operating variables. The results showed that, thermal efficiency and total annual costs decreased by 5.6% and 8% for KPCC system but increased 4.9% and 58% for KLACC system, respectively. Since the power-cooling efficiency of KLACC is 42% higher than KPCC it can be applied where the aim is cooling generation without considering economic aspects.

  13. Tetra-combined cogeneration system. Exergy and thermo economic evaluation; Sistema tetra combinado de cogeracao. Avaliacao exergetica e termoeconomica

    Energy Technology Data Exchange (ETDEWEB)

    Arriola, Domingo Wilson Garagatti [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: wgarriol@usp.br; Oliveira Junior, Silvio de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)]. E-mail: olivsilj@ipt.br

    2000-07-01

    This paper presents the description and the exergy and thermo economic evaluation of a new cogeneration system, called tetra-combined cogeneration system, that generates electricity and chilled water (for air conditioning purposes) and eventually steam. This system is composed of a gas turbine, a heat recovery steam generator, a condensation/extraction steam turbine and a hybrid absorption/steam ejection chiller. The exergy and thermo economic performance (exergy based costs of electricity, steam and chilled water production) of this system is compared with the performances of conventional cogeneration systems, pointing out the advantages and disadvantages of this new system. (author)

  14. Tetra-combined cogeneration system. Exergy and thermoeconomic evaluation; Sistema tetra combinado de cogeracao. Avaliacao exergetica e termoeconomica

    Energy Technology Data Exchange (ETDEWEB)

    Arriola, Domingo Wilson Garagatti [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: wgarriol@usp.br; Oliveira Junior, Silvio de [Instituto de Pesquisas Tecnologicas (IPT), Sao Paulo, SP (Brazil)]. E-mail: olivsilj@ipt.br

    2000-07-01

    The description and the exergy and thermo economic evaluation of a new cogeneration system, called tetra-combined cogeneration system, that generates electricity and chilled water (for air conditioning purposes) and eventually steam is presented. This system is composed of a gas turbine, a heat recovery steam generator, a condensation/extraction steam turbine and a hybrid absorption/steam ejection chiller.The exergy and thermo economic performance (exergy based costs of electricity, steam and chilled water production) of this system is compared with the performances of conventional cogeneration systems, pointing out the advantages and disadvantages of this new system. (author)

  15. Cogeneration techniques; Les techniques de cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-10-01

    This dossier about cogeneration techniques comprises 12 parts dealing successively with: the advantages of cogeneration (examples of installations, electrical and thermal efficiency); the combustion turbine (principle, performances, types); the alternative internal combustion engines (principle, types, rotation speed, comparative performances); the different configurations of cogeneration installations based on alternative engines and based on steam turbines (coal, heavy fuel and natural gas-fueled turbines); the environmental constraints of combustion turbines (pollutants, techniques of reduction of pollutant emissions); the environmental constraints of alternative internal combustion engines (gas and diesel engines); cogeneration and energy saving; the techniques of reduction of pollutant emissions (pollutants, unburnt hydrocarbons, primary and secondary (catalytic) techniques, post-combustion); the most-advanced configurations of cogeneration installations for enhanced performances (counter-pressure turbines, massive steam injection cycles, turbo-chargers); comparison between the performances of the different cogeneration techniques; the tri-generation technique (compression and absorption cycles). (J.S.)

  16. Thermoeconomic analysis and optimization of an ammonia–water power/cooling cogeneration cycle

    International Nuclear Information System (INIS)

    Zare, V.; Mahmoudi, S.M.S.; Yari, M.; Amidpour, M.

    2012-01-01

    The performance of an ammonia–water power/cooling cogeneration cycle is investigated and optimized paying more attention on the economic point of view. Thermodynamic and thermoeconomic models are developed in order to investigate the thermodynamic performance of the cycle and assess the unit cost of products. A parametric study is carried out and the cycle performance is optimized based on the thermal and exergy efficiencies as well as the sum of the unit costs of the system products. The results show that the sum of the unit cost of the cycle products obtained through thermoeconomic optimization is less than by around 18.6% and 25.9% compared to the cases when the cycle is optimized from the viewpoints of first and second laws of thermodynamics, respectively. It is also concluded that for each increase of $3/ton in unit cost of the steam as the heat source, the unit cost of the output power and cooling is increased by around $7.6/GJ and $15–19/GJ, respectively. -- Highlights: ► The theory of exergetic cost is applied to the case of ammonia–water power/cooling cycle. ► The cycle is optimized from the viewpoints of thermodynamics and economics. ► The economic optimization leads to a considerable reduction in the system product costs.

  17. Combined-cycle plants

    International Nuclear Information System (INIS)

    Valenti, M.

    1991-01-01

    This paper reports that as tougher emissions standards take hold throughout the industrialized world, manufacturers such as GE, Siemens, Foster Wheeler, and Asea Brown Boveri are designing advanced combined-cycle equipment that offers improved environmental performance without sacrificing power efficiency

  18. Combined cogeneration equipment containing gas turbine using low sulphur heavy stock as fuel

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Goro; Ishiki, Katsuhiko

    1988-03-10

    This paper describes the combined cogeneration in Chemical and Plastics Co. Madras (India) which uses low sulphur heavy stock (LSHS) as a fuel. By the combined cogeneration of gas turbine and boiler steam turbine power generation, the exhaust from the steam turbine is supplied to the factory as a process steam. This equipment has a capacity of 4835 kW in overall generation power and 23.5 tons/hrs. in steam evaporation. The gas turbine system is equipped with an axial-flow, 11 step compressor, an axial flow, 4 step turbine, and a single-can back flow combustor fixed to the intermediate casing. The temperature of the exhaust from the gas turbine is 542/sup 0/C. Low quality LSHS when burned exerts no influence on the service life of the turbine blades. The boiler is a horizontal bent pipe, forced circulation type, and the steam turbine is a back pressure control type. The fuel is treated with a horizontal, two drum, electrostatic separator to which a demulsifier is supplied, to be separated into oil and water. As to the vanadium salts contained in the fuels, a chemical liquid containing MgO as a major ingredient is added to the fuel prior to the combustion. Thereby, the melting temperature of the vanadium oxide is enhanced, which serves for prevention of the melting and adhesion of the vanadium oxide to the gas turbine. LSHS is a residual oil produced by the ordinary pressure distillation of India-produced crude oil, has a sulphur content of 1.75%, and is solid at room temperature. Attention should be paid to clogging of the pipings. The overall efficiency is 80%. The combined cogeneration can be coordinated with load variations of 10 - 20%. (12 figs, 1 tab)

  19. Cogeneration at FIAT AVIO (Italy)

    International Nuclear Information System (INIS)

    Cantoni, A.

    1991-01-01

    Brief notes are provided on the FIAT (Italy) - Foster Wheeler joint venture to equip about 20 FIAT manufacturing plants with 50 MW(e) combined cycle cogeneration plants which will make use of a gas turbine whose design is based on that of the successful General Electric aeronautic LM 6000 engine. The paper also discusses solutions, e.g., wet and dry methods, being considered for nitrogen ox des control, and cites the need in Italy for the optimization of Government licensing procedures for small and medium sized manufacturing firms opting for on-site power generation through cogeneration plants

  20. Thermodynamic analysis of SCW NPP cycles with thermo-chemical co-generation of hydrogen

    International Nuclear Information System (INIS)

    Naidin, N.; Mokry, S.; Monichan, R.; Chophla, K.; Pioro, I.; Naterer, G.; Gabriel, K.

    2009-01-01

    Research activities are currently conducted worldwide to develop Generation IV nuclear reactor concepts with the objective of improving thermal efficiency and increasing economic competitiveness of Generation IV Nuclear Power Plants (NPPs) compared to modern thermal power plants. The Super-Critical Water-cooled Reactor (SCWR) concept is one of the six Generation IV options chosen for further investigation and development in several countries including Canada and Russia. Water-cooled reactors operating at subcritical pressures (10 - 16 MPa) have provided a significant amount of electricity production for the past 50 years. However, the thermal efficiency of the current NPPs is not very high (30 - 35%). As such, more competitive designs, with higher thermal efficiencies, which will be close to that of modern thermal power plants (45 - 50%), need to be developed and implemented. Super-Critical Water (SCW) NPPs will have much higher operating parameters compared to current NPPs (i.e., steam pressures of about 25 MPa and steam outlet temperatures up to 625 o C). Furthermore, SCWRs operating at higher temperatures can facilitate an economical co-generation of hydrogen through thermochemical cycles (particularly, the copper-chlorine cycle) or direct high-temperature electrolysis. The two SCW NPP cycles proposed by this paper are based on direct, regenerative, no-reheat and single-reheat configurations. As such, the main parameters and performance in terms of thermal efficiency of the SCW NPP concepts mentioned above are being analyzed. The cycles are generally comprised of: an SCWR, a SC turbine, one deaerator, ten feedwater heaters, and pumps. The SC turbine of the no-reheat cycle consists of one High-Pressure (HP) cylinder and two Low-Pressure (LP) cylinders. Alternatively, the SC turbine for the single-reheat cycle is comprised of one High-Pressure (HP) cylinder, one Intermediate-Pressure (IP) cylinder and two Low-Pressure (LP) cylinders. Since the single-reheat option

  1. Energetic analysis of a novel vehicle power and cooling/heating cogeneration energy system using cascade cycles

    International Nuclear Information System (INIS)

    Yue, Chen; Han, Dong; Pu, Wenhao; He, Weifeng

    2015-01-01

    This study proposes and investigates a novel VCES (Vehicle power and cooling/heating Cogeneration Energy System), including a topping vehicle engine subsystem, and a bottoming waste-heat recovery subsystem which uses the zeotropic working fluid. The various grade exhaust and coolant waste-heat of the topping subsystem are cascade recovered by the bottoming subsystem, and slide-temperature thermal match in waste heat recovery heat exchangers and the condenser is considered also, obtaining power output and cooling/heating capacity. Based on the experimental data from an actual vehicle's energy demands and its waste-heat characteristics, the proposed VCES (vehicle cogeneration energy system) model is built and verified. Using ammonia-water as working fluid of the bottoming subsystem, integrated thermodynamic performances of the VCES are discussed through introducing three variables: an ambient temperature, the vehicle's velocity and the number of seated occupants. The influence of above three variables on the proposed VCES′ overall thermodynamic performance is analyzed by comparing it to a conventional VCES, and suitable operation conditions are recommended under cooling and heating conditions. - Highlights: • A novel vehicle cogeneration energy system is proposed. • Slide-temperature thermal match at two levels are considered. • Integration of the topping vehicle engine and bottoming waste heat recovery cycle is designed. • The cogeneration system model is built and verified based on experimental data. • Energy-saving potential of the proposed system is investigated

  2. Energy audit: thermal power, combined cycle, and cogeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Abbi, Yash Pal

    2012-07-01

    The availability of fossil fuels required for power plants is reducing and their costs increasing rapidly. This gives rise to increase in the cost of generation of electricity. But electricity regulators have to control the price of electricity so that consumers are not stressed with high costs. In addition, environmental considerations are forcing power plants to reduce CO2 emissions. Under these circumstances, power plants are constantly under pressure to improve the efficiency of operating plants, and to reduce fuel consumption. In order to progress in this direction, it is important that power plants regularly audit their energy use in terms of the operating plant heat rate and auxiliary power consumption. The author attempts to refresh the fundamentals of the science and engineering of thermal power plants, establish its link with the real power plant performance data through case studies, and further develop techno-economics of the energy efficiency improvement measures. This book will rekindle interest in energy audits and analysis of the data for designing and implementation of energy conservation measures on a continuous basis.

  3. High-temperature gas-cooled reactor steam cycle/cogeneration: lead project strategy plan

    International Nuclear Information System (INIS)

    1982-07-01

    The strategy, contained herein, for developing the HTGR system and introducing it into the energy marketplace is based on using the most developed technology path to establish a HTGR-Steam Cycle/Cogeneration (SC/C) Lead Project. Given the status of the HTGR-SC/C technology, a Lead Plant could be completed and operational by the mid 1990s. While there is remaining design and technology development that must be accomplished to fulfill technical and licensing requirements for a Lead Project commitment, the major barriers to the realization a HTGR-SC/C Lead Project are institutional in nature, e.g. budget priorities and constraints, cost/risk sharing between the public and private sector, Project organization and management, and Project financing. These problems are further complicated by the overall pervading issues of economic and regulatory instability that presently confront the utility and nuclear industries. This document addresses the major institutional issues associated with the HTGR-SC/C Lead Project and provides a starting point for discussions between prospective Lead Project participants toward the realization of such a Project

  4. Combined heat and power (cogeneration) plant based on renewable energy sources and electrochemical hydrogen systems

    Science.gov (United States)

    Grigor'ev, S. A.; Grigor'ev, A. S.; Kuleshov, N. V.; Fateev, V. N.; Kuleshov, V. N.

    2015-02-01

    The layout of a combined heat and power (cogeneration) plant based on renewable energy sources (RESs) and hydrogen electrochemical systems for the accumulation of energy via the direct and inverse conversion of the electrical energy from RESs into the chemical energy of hydrogen with the storage of the latter is described. Some efficient technical solutions on the use of electrochemical hydrogen systems in power engineering for the storage of energy with a cyclic energy conversion efficiency of more than 40% are proposed. It is shown that the storage of energy in the form of hydrogen is environmentally safe and considerably surpasses traditional accumulator batteries by its capacitance characteristics, being especially topical in the prolonged absence of energy supply from RESs, e.g., under the conditions of polar night and breathless weather. To provide the required heat consumption of an object during the peak period, it is proposed to burn some hydrogen in a boiler house.

  5. Biomass Gasification Combined Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Judith A. Kieffer

    2000-07-01

    Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

  6. Modeling and optimization of a novel solar chimney cogeneration power plant combined with solid oxide electrolysis/fuel cell

    International Nuclear Information System (INIS)

    Joneydi Shariatzadeh, O.; Refahi, A.H.; Abolhassani, S.S.; Rahmani, M.

    2015-01-01

    Highlights: • Proposed a solar chimney cogeneration power plant combined with solid oxide fuel cell. • Conducted single-objective economic optimization of cycle by genetic algorithm. • Stored surplus hydrogen in season solarium to supply electricity in winter by SOFC. - Abstract: Using solar chimney in desert areas like El Paso city in Texas, USA, with high intensity solar radiation is efficient and environmental friendly. However, one of the main challenges in terms of using solar chimneys is poor electricity generation at night. In this paper, a new power plant plan is proposed which simultaneously generates heat and electricity using a solar chimney with solid oxide fuel cells and solid oxide electrolysis cells. In one hand, the solar chimney generates electricity by sunlight and supplies a part of demand. Then, additional electricity is generated through the high temperature electrolysis which produces hydrogen that is stored in tanks and converted into electricity by solid oxide fuel cells. After designing and modeling the cycle components, the economic aspect of this power plant is considered numerically by means of genetic algorithm. The results indicate that, 0.28 kg/s hydrogen is produced at the peak of the radiation. With such a hydrogen production rate, this system supplies 79.26% and 37.04% of the demand in summer and winter respectively in a district of El Paso city.

  7. Life cycle optimization model for integrated cogeneration and energy systems applications in buildings

    Science.gov (United States)

    Osman, Ayat E.

    Energy use in commercial buildings constitutes a major proportion of the energy consumption and anthropogenic emissions in the USA. Cogeneration systems offer an opportunity to meet a building's electrical and thermal demands from a single energy source. To answer the question of what is the most beneficial and cost effective energy source(s) that can be used to meet the energy demands of the building, optimizations techniques have been implemented in some studies to find the optimum energy system based on reducing cost and maximizing revenues. Due to the significant environmental impacts that can result from meeting the energy demands in buildings, building design should incorporate environmental criteria in the decision making criteria. The objective of this research is to develop a framework and model to optimize a building's operation by integrating congregation systems and utility systems in order to meet the electrical, heating, and cooling demand by considering the potential life cycle environmental impact that might result from meeting those demands as well as the economical implications. Two LCA Optimization models have been developed within a framework that uses hourly building energy data, life cycle assessment (LCA), and mixed-integer linear programming (MILP). The objective functions that are used in the formulation of the problems include: (1) Minimizing life cycle primary energy consumption, (2) Minimizing global warming potential, (3) Minimizing tropospheric ozone precursor potential, (4) Minimizing acidification potential, (5) Minimizing NOx, SO 2 and CO2, and (6) Minimizing life cycle costs, considering a study period of ten years and the lifetime of equipment. The two LCA optimization models can be used for: (a) long term planning and operational analysis in buildings by analyzing the hourly energy use of a building during a day and (b) design and quick analysis of building operation based on periodic analysis of energy use of a building in a

  8. Cogeneration and local authorities; Cogeneration et collectivites territoriales

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    This conference is composed of 15 communications concerning cogeneration systems and applications in local communities. The main themes are: the regulation context and administrative procedures for cogeneration projects in France; legal aspects, risk covering, financing and sellback conditions for cogeneration systems; examples of cogeneration and tri-generation (with refrigeration energy) in different cities, airport, hospitals, campus, combined with the upgrading of district heating systems or municipal waste incineration plants. Impacts on energy savings and air pollution are also discussed

  9. Life cycle inventory of electricity cogeneration from bagasse in the South African sugar industry

    CSIR Research Space (South Africa)

    Mashoko, L

    2013-01-01

    Full Text Available The South African sugar industry has a potential for cogeneration of steam and electricity using bagasse. The sugar industry has the potential to generate about 960 MW per year from bagasse based on the average of 20 million tons of sugar cane...

  10. Optimal placement of combined heat and power scheme (cogeneration): application to an ethylbenzene plant

    International Nuclear Information System (INIS)

    Zainuddin Abd Manan; Lim Fang Yee

    2001-01-01

    Combined heat and power (CHP) scheme, also known as cogeneration is widely accepted as a highly efficient energy saving measure, particularly in medium to large scale chemical process plants. To date, CHP application is well established in the developed countries. The advantage of a CHP scheme for a chemical plant is two-fold: (i) drastically cut down on the electricity bill from on-site power generation (ii) to save the fuel bills through recovery of the quality waste heat from power generation for process heating. In order to be effective, a CHP scheme must be placed at the right temperature level in the context of the overall process. Failure to do so might render a CHP venture worthless. This paper discusses the procedure for an effective implementation of a CHP scheme. An ethylbenzene process is used as a case study. A key visualization tool known as the grand composite curves is used to provide an overall picture of the process heat source and heat sink profiles. The grand composite curve, which is generated based on the first principles of Pinch Analysis enables the CHP scheme to be optimally placed within the overall process scenario. (Author)

  11. The effective use of gas turbines and combined cycle technology in heat and electrical energy production

    International Nuclear Information System (INIS)

    Boehm, B.; Stark, E.

    1999-01-01

    The modernization of the energy industry in many countries is a real challenge for both, the policy makers as well as for the power industry. Especially, the efficient satisfaction of the heat and electrical demand of big cities will remain an interesting task for supply companies and hence for today engineers and economists, because the availability of natural gas from Russia and from other deposits owning countries for the decades to come, cogeneration by using modern gas turbines and combined cycle technologies is a key and corner stone of supply, not the least for its very low emission and small environmental loading. It is the intention of this paper, to demonstrate under resource to: 1) the high potential of natural gas-based cogeneration; 2) the high efficiency of gas turbines and combined cycle plants; 3) their flexibility to cover different demands; 4) the operational experience with gas turbines and combined cycle cogeneration plants; 5) the very good environmental behavior of gas turbines. Actually, the highest utilization of primary energy resources is afforded with natural gas and described technology. Future gradual rise of gas prices can bring about a shift from the present main application in high efficiency load plants to mid range load operation of cogeneration plants. (Author)

  12. Cogeneration system simulation/optimization

    International Nuclear Information System (INIS)

    Puppa, B.A.; Chandrashekar, M.

    1992-01-01

    Companies are increasingly turning to computer software programs to improve and streamline the analysis o cogeneration systems. This paper introduces a computer program which originated with research at the University of Waterloo. The program can simulate and optimize any type of layout of cogeneration plant. An application of the program to a cogeneration feasibility study for a university campus is described. The Steam and Power Plant Optimization System (SAPPOS) is a PC software package which allows users to model any type of steam/power plant on a component-by-component basis. Individual energy/steam balances can be done quickly to model any scenario. A typical days per month cogeneration simulation can also be carried out to provide a detailed monthly cash flow and energy forecast. This paper reports that SAPPOS can be used for scoping, feasibility, and preliminary design work, along with financial studies, gas contract studies, and optimizing the operation of completed plants. In the feasibility study presented, SAPPOS is used to evaluate both diesel engine and gas turbine combined cycle options

  13. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Tech., Stockholm (Sweden). Dept. of Energy Technology

    2002-02-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  14. Air bottoming cycle, an alternative to combined cycles. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaikko, J. [Royal Inst. of Techn., Stockholm (Sweden). Dept. of Energy Technology

    2001-10-01

    In this work, the idea of Air Bottoming Cycle (ABC) has been studied. The objectives for the work have been to establish an understanding of the concept for power and heat generation as well as to find - if possible - feasible concepts for future use in the Swedish energy system. Combined cycle in power generation is an established technology. In the conventional combined cycle, a gas turbine works as a topping cycle together with the steam (Rankine) bottoming cycle. In the ABC the steam bottoming cycle is replaced with a gas turbine (Brayton) bottoming cycle having air as a working fluid. The two gas turbines are thermally connected over a gas-to-gas heat exchanger. This concept promises savings in weight and cost, as well as operating benefits, compared to the Rankine bottoming technology. The ABC has been modelled using a heat balance program, and a parametric study for the concept optimisation as well as for off-design analysis has been performed. Performance of the ABC has been compared to other, established technologies. A preliminary economic evaluation has been made. As a result of the study, it is clarified that the Rankine bottoming cycle with steam remains superior to the ABC as regards electrical efficiency in the medium and large power scale. For small-scale applications (<10 MW{sub e}) where the thermodynamic advantage of the Rankine cycle is not dominating any longer and its economy is burdened by the heavy investment structure, the ABC becomes the better alternative for energy utilisation. A preliminary economic evaluation shows that (at energy prices autumn 2000) the ABC is at the same level as the comparable small-scale cogeneration installations. Due to high power-to-heat ratio however, higher electricity prices will favour the ABC. One interesting feature of the ABC is that about 50% of the dissipated low-value heat from the cycle is carried by clean (sterile) air at the temperature around 200 deg C. This air can be utilised for space heating or

  15. Thermodynamic performance analysis and optimization of DMC (Dual Miller Cycle) cogeneration system by considering exergetic performance coefficient and total exergy output criteria

    International Nuclear Information System (INIS)

    Ust, Yasin; Arslan, Feyyaz; Ozsari, Ibrahim; Cakir, Mehmet

    2015-01-01

    Miller cycle engines are one of the popular engine concepts that are available for improving performance, reducing fuel consumption and NO x emissions. There are many research studies that investigated the modification of existing conventional engines for operation on a Miller cycle. In this context, a comparative performance analysis and optimization based on exergetic performance criterion, total exergy output and exergy efficiency has been carried out for an irreversible Dual–Miller Cycle cogeneration system having finite-rate of heat transfer, heat leak and internal irreversibilities. The EPC (Exergetic Performance Coefficient) criterion defined as the ratio of total exergy output to the loss rate of availability. Performance analysis has been also extended to the Otto–Miller and Diesel-Miller cogeneration cycles which may be considered as two special cases of the Dual–Miller cycle. The effect of the design parameters such as compression ratio, pressure ratio, cut-off ratio, Miller cycle ratio, heat consumer temperature ratio, allocation ratio and the ratio of power to heat consumed have also been investigated. The results obtained from this paper will provide guidance for the design of Dual–Miller Cycle cogeneration system and can be used for selection of optimal design parameters. - Highlights: • A thermodynamic performance estimation tool for DM cogeneration cycle is presented. • Using the model two special cases OM and dM cogeneration cycles can be analyzed. • The effects of r M , ψ, χ 2 and R have been investigated. • The results evaluate exergy output and environmental aspects together.

  16. Ecological assessment and economic feasibility to utilize first generation biofuels in cogeneration output cycle - The case of Lithuania

    International Nuclear Information System (INIS)

    Raslavicius, Laurencas; Bazaras, Zilvinas

    2010-01-01

    In this article, diverse liquid biofuels of the first generation were compared as partial or infant substitutes for fossil diesel fuel applied in cogeneration plant of the average capacity of 340 kW. The study concentrates on agricultural and economic conditions as well as legislative basis distinctive to Lithuania. At the laboratory of the Lithuanian University of Agriculture Institute of Agro-Engineering an experimental diesel engine powered generator was fuelled with rapeseed oil methyl ester (pure and in the blend with fossil diesel and dyed diesel fuels) and rapeseed oil with excellent energy balances and emissions characteristics more favorable than fossil diesel. Detailed estimations were proposed in order to assess the economic feasibility of complementing renewable electricity and heat generated in the final output cycle. The carried out analysis showed, that good perspectives are forecasted for using diesel engines in cogeneration plants, if they run on rapeseed oil produced by farmers themselves. The operation of such a plant would realize 184960 EUR of annual income for sold electricity, allowing to pay annual depreciation expenses and exceed the production cost for thermal energy to be 0.033 EUR/kW h. This price lies under the established one by the centralized energy suppliers, accordingly 0.058 EUR/kW h. (author)

  17. GE will finance 614-MW cogeneration plant

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    The General Electric Power Funding Corporation, a unit of GE Capital, will provide up to $870 million in construction and permanent financing, and letters of credit to Cogen Technologies of Houston, Texas. The agreement will fund the construction of a 614-megawatt (MW), combined-cycle cogeneration plant to be built in Linden, New Jersey, and for the purchase of gas properties. The plant will be owned by Cogen Technologies. The financing is one of the largest packages ever for a cogeneration plant, GE said

  18. Novel, cost-effective configurations of combined power plants for small-scale cogeneration from biomass: Feasibility study and performance optimization

    International Nuclear Information System (INIS)

    Amirante, Riccardo; Tamburrano, Paolo

    2015-01-01

    Highlights: • A cheap small combined cycle for cogeneration from biomass is proposed. • An optimization procedure is utilized to explore its potential. • Two configurations employing two different heat exchangers are considered. • The maximum electrical efficiency is 25%, the maximum overall efficiency is 70%. • The operation in load following mode is effective for both configurations. - Abstract: The aim of this paper is to demonstrate that, thanks to recent advances in designing micro steam expanders and gas to gas heat exchangers, the use of small combined cycles for simultaneous generation of heat and power from the external combustion of solid biomass and low quality biofuels is feasible. In particular, a novel typology of combined cycle that has the potential both to be cost-effective and to achieve a high level of efficiency is presented. In the small combined cycle proposed, a commercially available micro-steam turbine is utilized as the steam expander of the bottoming cycle, while the conventional microturbine of the topping cycle is replaced by a cheaper automotive turbocharger. The feasibility, reliability and availability of the required mechanical and thermal components are thoroughly investigated. In order to explore the potential of such a novel typology of power plant, an optimization procedure, based on a genetic algorithm combined with a computing code, is utilized to analyze the trade-off between the maximization of the electrical efficiency and the maximization of the thermal efficiency. Two design optimizations are performed: the first one makes use of the innovative “Immersed Particle Heat Exchanger”, whilst a nickel alloy heat exchanger is used in the other one. After selecting the optimum combination of the design parameters, the operation in load following mode is also assessed for both configurations

  19. Review of the cost estimate and schedule for the 2240-MWt high-temperature gas-cooled reactor steam-cycle/cogeneration lead plant

    International Nuclear Information System (INIS)

    1983-09-01

    This report documents Bechtel's review of the cost estimate and schedule for the 2240 MWt High Temperature Gas-Cooled Reactor Steam Cycle/Cogeneration (HTGR-SC/C) Lead Plant. The overall objective of the review is to verify that the 1982 update of the cost estimate and schedule for the Lead Plant are reasonable and consistent with current power plant experience

  20. Design-theoretical study of cascade CO2 sub-critical mechanical compression/butane ejector cooling cycle

    KAUST Repository

    Petrenko, V.O.; Huang, B.J.; Ierin, V.O.

    2011-01-01

    In this paper an innovative micro-trigeneration system composed of a cogeneration system and a cascade refrigeration cycle is proposed. The cogeneration system is a combined heat and power system for electricity generation and heat production

  1. Airbreathing combined cycle engine systems

    Science.gov (United States)

    Rohde, John

    1992-01-01

    The Air Force and NASA share a common interest in developing advanced propulsion systems for commercial and military aerospace vehicles which require efficient acceleration and cruise operation in the Mach 4 to 6 flight regime. The principle engine of interest is the turboramjet; however, other combined cycles such as the turboscramjet, air turborocket, supercharged ejector ramjet, ejector ramjet, and air liquefaction based propulsion are also of interest. Over the past months careful planning and program implementation have resulted in a number of development efforts that will lead to a broad technology base for those combined cycle propulsion systems. Individual development programs are underway in thermal management, controls materials, endothermic hydrocarbon fuels, air intake systems, nozzle exhaust systems, gas turbines and ramjet ramburners.

  2. ASPEN simulation of cogeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Ligang Zheng [CANMET Energy Technology Center, Natural Resources Canada, Nepean, ONT (Canada); Furimsky, E. [IMAG Group, Ottawa, ONT (Canada)

    2003-07-01

    A detailed flow sheet of the combined cycle cogeneration plant fuelled by natural gas was prepared. The model for simulation of this plant was developed using the ASPEN PLUS software. The results generated using this model were compared with the operating data of the commercial plant generating about 43.6 MW of electricity by gas turbine and 28.6 MW of electricity by steam turbine. The electricity is supplied to the grid, whereas the low pressure steam is utilised locally for heating purposes. The key data generated using the ASPEN model are in good agreement with the operating data. (author)

  3. ASPEN simulation of cogeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Zheng Ligang E-mail: lzheng@nrcan.gc.ca; Furimsky, Edward

    2003-07-01

    A detailed flow sheet of the combined cycle cogeneration plant fuelled by natural gas was prepared. The model for simulation of this plant was developed using the ASPEN PLUS software. The results generated using this model were compared with the operating data of the commercial plant generating about 43.6 MW of electricity by gas turbine and 28.6 MW of electricity by steam turbine. The electricity is supplied to the grid, whereas the low pressure steam is utilised locally for heating purposes. The key data generated using the ASPEN model are in good agreement with the operating data.

  4. ASPEN simulation of cogeneration plants

    International Nuclear Information System (INIS)

    Zheng Ligang; Furimsky, Edward

    2003-01-01

    A detailed flow sheet of the combined cycle cogeneration plant fuelled by natural gas was prepared. The model for simulation of this plant was developed using the ASPEN PLUS software. The results generated using this model were compared with the operating data of the commercial plant generating about 43.6 MW of electricity by gas turbine and 28.6 MW of electricity by steam turbine. The electricity is supplied to the grid, whereas the low pressure steam is utilised locally for heating purposes. The key data generated using the ASPEN model are in good agreement with the operating data

  5. A new market risk model for cogeneration project financing---combined heat and power development without a power purchase agreement

    Science.gov (United States)

    Lockwood, Timothy A.

    Federal legislative changes in 2006 no longer entitle cogeneration project financings by law to receive the benefit of a power purchase agreement underwritten by an investment-grade investor-owned utility. Consequently, this research explored the need for a new market-risk model for future cogeneration and combined heat and power (CHP) project financing. CHP project investment represents a potentially enormous energy efficiency benefit through its application by reducing fossil fuel use up to 55% when compared to traditional energy generation, and concurrently eliminates constituent air emissions up to 50%, including global warming gases. As a supplemental approach to a comprehensive technical analysis, a quantitative multivariate modeling was also used to test the statistical validity and reliability of host facility energy demand and CHP supply ratios in predicting the economic performance of CHP project financing. The resulting analytical models, although not statistically reliable at this time, suggest a radically simplified CHP design method for future profitable CHP investments using four easily attainable energy ratios. This design method shows that financially successful CHP adoption occurs when the average system heat-to-power-ratio supply is less than or equal to the average host-convertible-energy-ratio, and when the average nominally-rated capacity is less than average host facility-load-factor demands. New CHP investments can play a role in solving the world-wide problem of accommodating growing energy demand while preserving our precious and irreplaceable air quality for future generations.

  6. Cogeneration feasibility: Otis Elevator Company and Polychrome Corporation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1982-05-01

    The purpose of this study was to assess the feasibility of cogeneration at Otis Elevator Company and Polychrome Corporation located in Westchester County, New York. Each plant and its associated thermal and electrical load is reviewed. Three basic cycles for the cogeneration are investigated: power only, power generation with waste heat recovery, and combined cycle. Each case was assessed economically, beginning with a screening method to suggest those configurations most likely to be implemented and continuing through an assessment of the regulatory environment for cogeneration and an analysis of rate structures for buy back power, displaced power, and supplementing service. It is concluded that: for a plant designed to supply the combined loads of the two corporations, interconnection costs coupled to the coincidence of load result in unfavorable economics; for separate cogeneration plants, owned and operated by each individual corporation, energy consumption patterns and the current regulatory environment, in particular the existing and proposed cogeneration system rate structures, do not permit viable economics for the proposed plants; but if the proposed cycle were owned and operated by a new entity (neither Otis/Polychrome nor the utility), an economic scheme with marginal financial benefits can be developed and may be worthy of further study. (LEW)

  7. Control strategies and cycling demands for Li-ion storage batteries in residential micro-cogeneration systems

    International Nuclear Information System (INIS)

    Darcovich, K.; Kenney, B.; MacNeil, D.D.; Armstrong, M.M.

    2015-01-01

    Highlights: • Canadian home energy system modeled with PV, ICE CHP, battery and power grid. • Battery function is modeled on fundamental electrochemical principles. • Techno-economics of control strategies assessed. • Impact of control strategies battery cycles is developed for wear analysis. • Non-monotonic nature of battery cycles with transient renewables is discussed. - Abstract: Energy storage units have become important components in residential micro-cogeneration (MCG) systems. As MCG systems are often connected to single residences or buildings in a wide variety of settings, they are frequently unique and highly customized. Lithium-ion batteries have recently gained some profile as energy storage units of choice, because of their good capacity, high efficiency, robustness and ability to meet the demands of typical residential electrical loads. In the present work, modeled scenarios are explored which examine the performance of a MCG system with an internal combustion engine, photovoltaic input and a Li-ion storage battery. An electricity demand profile from new data collected in Ottawa, Canada is used to provide a full year energy use context for the analyses. The demands placed on the battery are examined to assess the suitability of the battery size and performance, as well as control related functionalities which reveal significantly varying battery use, and led to a quantitative expression for equivalent cycles. The energy use simulations are derived from electrochemical fundamentals adapted for a larger battery pack. Simulation output provides the basis for techno-economic commentary on how to assess large-scale Li-ion batteries for effective electrical storage purposes in MCG systems, and the impact of the nature of the control strategy on the battery service life

  8. Modelling of a chemisorption refrigeration and power cogeneration system

    International Nuclear Information System (INIS)

    Bao, Huashan; Wang, Yaodong; Roskilly, Anthony Paul

    2014-01-01

    Highlights: • An adsorption cogeneration was proposed and simulated for cooling and electricity. • A dynamic model was built and studied to demonstrate the variability of the system. • A dynamic model included the complex coupling of thermodynamic and chemical kinetic. • Mutual constrains between main components and optimisation methods were discussed. • The highest theoretical COP and exergy efficiency of cogeneration is 0.57 and 0.62. - Abstract: The present work for the first time explores the possibility of a small-scale cogeneration unit by combining solid–gas chemisorption refrigeration cycle and a scroll expander. The innovation in this work is the capability of producing refrigeration and electricity continuously and simultaneously without aggravating the energy scarcity and environmental impact. Individual modelling for each component, which has been validated by experimental data, was firstly investigated in order to identify the proper operation condition for the cogeneration mode achieving 1000 W power output. Subsequently, with the integrated modelling of two components the cogeneration performance was studied to demonstrate the viability of this concept. However, because of the mutual constraint between the chemisorption and the expansion when they link in series, the power output of the cogeneration mode was only around one third of the original expectation under the same condition identified in the individual modelling. Methods of improving the global performance including the selection of reactive mediums were also discussed and would be of referable value for the future practical investigation

  9. Cogeneration: One way to use biomass efficiently

    International Nuclear Information System (INIS)

    Gustavsson, L.; Johansson, B.

    1993-01-01

    Cogeneration in district heating systems is the most energy-efficient way to convert biomass into heat and electricity with current or nearly commercial technologies. Methanol produced from biomass and used in vehicles instead of petrol or diesel could reduce carbon dioxide emissions nearly as much per unit of biomass as if the biomass were used to replace natural gas for cogeneration, but at some higher cost per unit of carbon dioxide reduction. The most energy-efficient way to use biomass for cogeneration appears to be combined cycle technology, and the world's first demonstration plant is now being built. Potentially, this technology can be used for electricity production in Swedish district heating systems to provide nearly 20% of current Swedish electricity production, while simultaneously reducing carbon dioxide emissions from the district heating systems by some 55%. The heat costs from cogeneration with biomass are higher than the heat costs from fossil fuel plants at current fuel prices. Biomass can only compete with fossil fuel if other advantages, for example a lower environmental impact are considered. (au) (35 refs.)

  10. Entropy, exergy, and cost analyses of solar driven cogeneration systems using supercritical CO_2 Brayton cycles and MEE-TVC desalination system

    International Nuclear Information System (INIS)

    Kouta, Amine; Al-Sulaiman, Fahad; Atif, Maimoon; Marshad, Saud Bin

    2016-01-01

    Highlights: • The entropy, exergy, and cost analyses for two solar cogeneration configurations are conducted. • The recompression cogeneration cycle achieves lower LCOE as compared to the regeneration cogeneration cycle. • The solar tower is the largest contributor to entropy generation in both configurations reaching almost 80%. • The specific entropy generation in the MEE-TVC decreases with decreasing the fraction. - Abstract: In this study, performance and cost analyses are conducted for a solar power tower integrated with supercritical CO_2 (sCO_2) Brayton cycles for power production and a multiple effect evaporation with a thermal vapor compression (MEE-TVC) desalination system for water production. The study is performed for two configurations based on two different supercritical cycles: the regeneration and recompression sCO_2 Brayton cycles. A two-tank molten salt storage is utilized to ensure a uniform operation throughout the day. From the entropy analysis, it was shown that the solar tower is the largest contributor to entropy generation in both configurations, reaching almost 80% from the total entropy generation, followed by the MEE-TVC desalination system, and the sCO_2 power cycle. The entropy generation in the two-tank thermal storage is negligible, around 0.3% from the total generation. In the MEE-TVC system the highest contributing component is the steam jet ejector, which is varying between 50% and 60% for different number of effects. The specific entropy generation in the MEE-TVC decreases as the fraction of the input heat to the desalination system decreases; while the specific entropy generation of the sCO_2 cycle remains constant. The cost analysis performed for different regions in Saudi Arabia and the findings reveal that the regions characterized by the highest average solar irradiation throughout the year have the lowest LCOE and LCOW values. The region achieving the lowest cost is Yanbu, followed by Khabt Al-Ghusn in the second

  11. Alternative ORC bottoming cycles FOR combined cycle power plants

    International Nuclear Information System (INIS)

    Chacartegui, R.; Sanchez, D.; Munoz, J.M.; Sanchez, T.

    2009-01-01

    In this work, low temperature Organic Rankine Cycles are studied as bottoming cycle in medium and large scale combined cycle power plants. The analysis aims to show the interest of using these alternative cycles with high efficiency heavy duty gas turbines, for example recuperative gas turbines with lower gas turbine exhaust temperatures than in conventional combined cycle gas turbines. The following organic fluids have been considered: R113, R245, isobutene, toluene, cyclohexane and isopentane. Competitive results have been obtained for toluene and cyclohexane ORC combined cycles, with reasonably high global efficiencies. The paper is structured in four main parts. A review of combined cycle and ORC cycle technologies is presented, followed by a thermodynamic analysis of combined cycles with commercial gas turbines and ORC low temperature bottoming cycles. Then, a parametric optimization of an ORC combined cycle plant is performed in order to achieve a better integration between these two technologies. Finally, some economic considerations related to the use of ORC in combined cycles are discussed.

  12. Optimum gas turbine cycle for combined cycle power plant

    International Nuclear Information System (INIS)

    Polyzakis, A.L.; Koroneos, C.; Xydis, G.

    2008-01-01

    The gas turbine based power plant is characterized by its relatively low capital cost compared with the steam power plant. It has environmental advantages and short construction lead time. However, conventional industrial engines have lower efficiencies, especially at part load. One of the technologies adopted nowadays for efficiency improvement is the 'combined cycle'. The combined cycle technology is now well established and offers superior efficiency to any of the competing gas turbine based systems that are likely to be available in the medium term for large scale power generation applications. This paper has as objective the optimization of a combined cycle power plant describing and comparing four different gas turbine cycles: simple cycle, intercooled cycle, reheated cycle and intercooled and reheated cycle. The proposed combined cycle plant would produce 300 MW of power (200 MW from the gas turbine and 100 MW from the steam turbine). The results showed that the reheated gas turbine is the most desirable overall, mainly because of its high turbine exhaust gas temperature and resulting high thermal efficiency of the bottoming steam cycle. The optimal gas turbine (GT) cycle will lead to a more efficient combined cycle power plant (CCPP), and this will result in great savings. The initial approach adopted is to investigate independently the four theoretically possible configurations of the gas plant. On the basis of combining these with a single pressure Rankine cycle, the optimum gas scheme is found. Once the gas turbine is selected, the next step is to investigate the impact of the steam cycle design and parameters on the overall performance of the plant, in order to choose the combined cycle offering the best fit with the objectives of the work as depicted above. Each alterative cycle was studied, aiming to find the best option from the standpoint of overall efficiency, installation and operational costs, maintainability and reliability for a combined power

  13. Energy and cost saving results for advanced technology systems from the Cogeneration Technology Alternatives Study (CTAS)

    Science.gov (United States)

    Sagerman, G. D.; Barna, G. J.; Burns, R. K.

    1979-01-01

    An overview of the organization and methodology of the Cogeneration Technology Alternatives Study is presented. The objectives of the study were to identify the most attractive advanced energy conversion systems for industrial cogeneration applications in the future and to assess the advantages of advanced technology systems compared to those systems commercially available today. Advanced systems studied include steam turbines, open and closed cycle gas turbines, combined cycles, diesel engines, Stirling engines, phosphoric acid and molten carbonate fuel cells and thermionics. Steam turbines, open cycle gas turbines, combined cycles, and diesel engines were also analyzed in versions typical of today's commercially available technology to provide a base against which to measure the advanced systems. Cogeneration applications in the major energy consuming manufacturing industries were considered. Results of the study in terms of plant level energy savings, annual energy cost savings and economic attractiveness are presented for the various energy conversion systems considered.

  14. Cogeneration Systems; Sistemas de Cogeneracion

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez M, Manuel F; Huante P, Liborio; Romo M, Cesar A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    The present article deals on relevant aspects on the subject of cogeneration within the Mexican territorial limits. In the first place it is presented the role of Mexico in terms of its cogeneration potential, the type of service that has obtained from this predominant modality of cogeneration for self-supplying, the most propitious sectors to develop it, its legislations on the matter, the projects made for the implementation of cogeneration plants, as well as the existing cogeneration schemes for its respective optimization proposals. Without leaving out the analysis on the different types of evaluation on the efficiency of cogeneration systems and the aspects to consider for the election of a generation cycle. [Spanish] El presente articulo trata sobre aspectos relevantes en materia de cogeneracion dentro de los limites territoriales de la nacion mexicana. Se muestra en primer lugar el papel de Mexico en terminos de su potencial de cogeneracion, el tipo de servicio que ha obtenido de esta predominantemente (modalidad de cogeneracion para autoabastecimiento), los sectores mas propicios para desarrollarla, sus legislaciones al respecto, los proyectos realizados para la implementacion de plantas de cogeneracion, asi como los esquemas de cogeneracion existentes con sus respectivas propuestas de optimizacion. Sin dejar de lado el analisis sobre los distintos tipos de evaluacion de la eficiencia de sistemas de cogeneracion y los aspectos a considerar para la eleccion de un ciclo de generacion.

  15. Cogeneration in Italian agricultural industry

    International Nuclear Information System (INIS)

    Bonfitto, E.; Jacoboni, S.

    1991-01-01

    This paper examines the technical, environmental and economical feasibility of an industrial cogeneration system which incorporates combined gas-steam cycles and a biomass/agricultural waste sludge fired fluidized bed combustion system. It cites the suitability of the use of fluidized bed combustion for the combustion of biomass and agricultural waste sludges - high combustion efficiency, uniform and relatively low combustion temperatures (850 C) within the combustion chamber to reduce scaling, reduced nitrogen oxide and micro-pollutant emissions, the possibility to control exhaust gas acidity through the injection of calcium carbonates, the possibility of the contemporaneous feeding of different fuels. Reference is made to test results obtained with an ENEL (Italian National Electricity Board) pilot plant fired by vineyard wastes. Attention is given to an analysis of the fuel's physical-chemical characteristics and the resulting flue gas chemical composition and ash characteristics. Comparisons are made with legal release limits

  16. Studies of a Combined-Cycle Engine

    OpenAIRE

    苅田, 丈士; KANDA, Takeshi

    2003-01-01

    For a Single-Stage-to-Orbit (SSTO) aerospace plane (Fig.1), several engines will be necessary to reach orbit. The combined-cycle engine incorporates several operational modes in a single engine. Study of the combined cycle engine has a long history, and several kinds of such engines have been proposed and studied. When several engines are mounted on a vehicle, each engine of the system will show a performance higher than that of the combined cycle engine. However, during the operation of one ...

  17. Steam process cogeneration using nuclear energy

    International Nuclear Information System (INIS)

    Alonso, G.; Ramirez, R.

    2010-10-01

    Use of energy in a sustainable manner is to make processes more efficient. Oil industry requires of electricity and steam for refinery and petrochemical processes, nuclear energy can be a clean energy alternative. Cogeneration is an option to be assessed by Mexico to provide additional value to electricity generation. Mexico is a country with oil resources that requires process heat for gasoline production among other things. With the concern about the climate change and sustain ability policies it is adequate to use cogeneration as a way to optimize energy resources. Currently there is a national program that considers cogeneration for several Mexican refineries, and the first choices are combined cycle plants and thermo power plants using residual oil. This is long term program. The pebble bed modular reactor (PBMR) is a next generation reactors that works with very high temperatures that can be used to produce steam process along with electricity, in this work two different couplings are assessed for the PBMR reactor to produce steam process, the two couplings are compared for using in the Mexican refineries and some conclusions are given. (Author)

  18. A novel nuclear combined power and cooling system integrating high temperature gas-cooled reactor with ammonia–water cycle

    International Nuclear Information System (INIS)

    Luo, Chending; Zhao, Fuqiang; Zhang, Na

    2014-01-01

    Highlights: • We propose a novel nuclear ammonia–water power and cooling cogeneration system. • The high temperature reactor is inherently safe, with exhaust heat fully recovered. • The thermal performances are improved compared with nuclear combined cycle. • The base case attains an energy efficiency of 69.9% and exergy efficiency of 72.5%. • Energy conservation and emission reduction are achieved in this cogeneration way. - Abstract: A nuclear ammonia–water power and refrigeration cogeneration system (NAPR) has been proposed and analyzed in this paper. It consists of a closed high temperature gas-cooled reactor (HTGR) topping Brayton cycle and a modified ammonia water power/refrigeration combined bottoming cycle (APR). The HTGR is an inherently safe reactor, and thus could be stable, flexible and suitable for various energy supply situation, and its exhaust heat is fully recovered by the mixture of ammonia and water in the bottoming cycle. To reduce exergy losses and enhance outputs, the ammonia concentrations of the bottoming cycle working fluid are optimized in both power and refrigeration processes. With the HTGR of 200 MW thermal capacity and 900 °C/70 bar reactor-core-outlet helium, the system achieves 88.8 MW net electrical output and 9.27 MW refrigeration capacity, and also attains an energy efficiency of 69.9% and exergy efficiency of 72.5%, which are higher by 5.3%-points and 2.6%-points as compared with the nuclear combined cycle (NCC, like a conventional gas/steam power-only combined cycle while the topping cycle is a closed HTGR Brayton cycle) with the same nuclear energy input. Compared with conventional separate power and refrigeration generation systems, the fossil fuel saving (based on CH 4 ) and CO 2 emission reduction of base-case NAPR could reach ∼9.66 × 10 4 t/y and ∼26.6 × 10 4 t/y, respectively. The system integration accomplishes the safe and high-efficiency utilization of nuclear energy by power and refrigeration

  19. Bifuel coal-gas combined cycles

    International Nuclear Information System (INIS)

    Chmielniak, Tadeusz; Kotowicz, Janusz; Lyczko, Jacek

    1997-01-01

    This paper describes basic ways of realization of bi fuel cool-gas combined cycles. The criterion of classification of the systems specification is a joint of the gas pail with the steam part: a) The gas turbine flue gases are introduced into the steam boiler combustion chamber (the serial, hot wind box). b) Bypass of the beat exchangers at the steam turbine unit and/or the steam boiler, by use the waste heat exchangers, or waste boiler at the gas turbine unit (the parallel-coupled). c) The mixed, it's a combination of the two upper. The analysis of the parallel system has been specially presented. In derived formulas for the total efficiency of the bi fuel parallel combined cycle balance equations have been used. This formulas can be used for planning new combined cycle power plants and for modernization existing steam power plants. It was made a discussion about influence of the ratio the gas and the steam turbine electric power on the cycle efficiency in care of the full and the part load of the bi fuel combined cycle power plant. The various systems of the joint of the gas part with the steam part have been examined. The selected results of the calculations have been attached. The models and the numerical simulations have been based on data from the existing steam power plants and real gas turbine units. (Author)

  20. Combined rankine and vapor compression cycles

    Science.gov (United States)

    Radcliff, Thomas D.; Biederman, Bruce P.; Brasz, Joost J.

    2005-04-19

    An organic rankine cycle system is combined with a vapor compression cycle system with the turbine generator of the organic rankine cycle generating the power necessary to operate the motor of the refrigerant compressor. The vapor compression cycle is applied with its evaporator cooling the inlet air into a gas turbine, and the organic rankine cycle is applied to receive heat from a gas turbine exhaust to heat its boiler within one embodiment, a common condenser is used for the organic rankine cycle and the vapor compression cycle, with a common refrigerant, R-245a being circulated within both systems. In another embodiment, the turbine driven generator has a common shaft connected to the compressor to thereby eliminate the need for a separate motor to drive the compressor. In another embodiment, an organic rankine cycle system is applied to an internal combustion engine to cool the fluids thereof, and the turbo charged air is cooled first by the organic rankine cycle system and then by an air conditioner prior to passing into the intake of the engine.

  1. Cogeneration for Brazil

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    Almost all the electric power in Brazil comes from large-scale hydroelectric plants: only about 3% comes from cogeneration. But, now that the barriers which discouraged cogeneration are being removed, there will be more and more investment in cogeneration and distributed generation. The circumstances which have brought about these changes are described. It is expected that cogeneration will be responsible for producing 10-15% of Brazil's electricity by 2010 and the demand for cogeneration will reach 11-17 GW. It is concluded that Brazil represents one of the world's most attractive market for cogeneration and distributed generation

  2. Termoacu Cogeneration: gas, power and oil; Cogeracao Termoacu: gas, energia e oleo

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Geraldo Jose; Gomes, Cicero Sena Moreira [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    This paper describes the evolution of a project that involves cogeneration of power and steam for continuous injection in oil wells in the fields of Alto do Rodrigues and Estreito, in Rio Grande do Norte, Brazil. The project combines a PETROBRAS intention for recovering heavy oil in that area with partners intention of generating power to connect in a critical point of the Brazilian Electric System. PETROBRAS studies began in the nineties, when oil wells in that area became old end showed the necessity of some oil recovery technology. In 1999, PETROBRAS and Guaraniana made a partnership for implementation of Termoacu Combined Cycle, that would begin operation as a cogeneration plant for thirteen years, and as combined cycle from that point. The profile of steam injection has been adapted to a new one to comply with the powe r capacity of the Plant, and will operate eight years as a cogeneration plant , four years as a combined cycle with cogeneration and after twelve years as a complete combined cycle with 500 MW of capacity. The project integrates a gas pipeline, a Thermal Power Plant, a Transmission Line to connect to the grid and a Steam Pipeline for steam injection at Estreito and Alto do Rodrigues fields. (author)

  3. Maximisation of Combined Cycle Power Plant Efficiency

    Directory of Open Access Journals (Sweden)

    Janusz Kotowicz

    2015-12-01

    Full Text Available The paper presents concepts for increasing the efficiency of a modern combined cycle power plant. Improvement of gas turbine performance indicators as well as recovering heat from the air cooling the gas turbine’s flow system enable reaching gross electrical efficiencies of around 65%. Analyses for a wide range of compressor pressure ratios were performed. Operating characteristics were developed for the analysed combined cycle plant, for different types of open air cooling arrangements of the gas turbine’s expander: convective, transpiration and film.

  4. Diagnostic system for combine cycle power plant

    International Nuclear Information System (INIS)

    Shimizu, Yujiro; Nomura, Masumi; Tanaka, Satoshi; Ito, Ryoji; Kita, Yoshiyuki

    2000-01-01

    We developed the Diagnostic System for Combined Cycle Power Plant which enables inexperienced operators as well as experienced operators to cope with abnormal conditions of Combined Cycle Power Plant. The features of this system are the Estimate of Emergency Level for Operation and the Prediction of Subsequent Abnormality, adding to the Diagnosis of Cause and the Operation Guidance. Moreover in this system, Diagnosis of Cause was improved by using our original method and support screens can be displayed for educational means in normal condition as well. (Authors)

  5. Simulation of a combined-cycle engine

    Science.gov (United States)

    Vangerpen, Jon

    1991-01-01

    A FORTRAN computer program was developed to simulate the performance of combined-cycle engines. These engines combine features of both gas turbines and reciprocating engines. The computer program can simulate both design point and off-design operation. Widely varying engine configurations can be evaluated for their power, performance, and efficiency as well as the influence of altitude and air speed. Although the program was developed to simulate aircraft engines, it can be used with equal success for stationary and automative applications.

  6. The merit of cogeneration: Measuring and rewarding performance

    International Nuclear Information System (INIS)

    Verbruggen, Aviel

    2008-01-01

    Cogeneration or combined heat and power (CHP) is a thermal power generation cycle with the merit of recovering part or all of the heat that is fatally discarded by such cycles. This merit of higher efficiency is subject of rewarding by public authorities. When the EU enacts CHP promotion in a Directive (1997-2004), crucial measurement and qualification issues remain unsolved. CEN (coordinator of the European Bureaus of Standards) contributes in clarifying the measurement of CHP activities, but shortfalls remain, while CEN bypasses the debate on qualifying CHP performance. This article offers appropriate methods for measuring CHP activities based on design characteristics of the plants. The co-generated electric output is a necessary and sufficient indicator of CHP merit and performance. Regulators can extend this indicator, but should avoid the perverse effects of biased external benchmarking as the EU Directive entails

  7. Rocket Based Combined Cycle (RBCC) engine inlet

    Science.gov (United States)

    2004-01-01

    Pictured is a component of the Rocket Based Combined Cycle (RBCC) engine. This engine was designed to ultimately serve as the near term basis for Two Stage to Orbit (TSTO) air breathing propulsion systems and ultimately a Single Stage to Orbit (SSTO) air breathing propulsion system.

  8. Development Activities on Airbreathing Combined Cycle Engines

    Science.gov (United States)

    McArthur, J. Craig; Lyles, Garry (Technical Monitor)

    2000-01-01

    Contents include the following: Advanced reusable transportation(ART); aerojet and rocketdyne tests, RBCC focused concept flowpaths,fabricate flight weigh, test select components, document ART project, Istar (Integrated system test of an airbreathing rocket); combined cycle propulsion testbed;hydrocarbon demonstrator tracebility; Istar engine system and vehicle system closure study; and Istar project planning.

  9. Feasibility study of a biomass-fired cogeneration plant Groningen, Netherlands

    International Nuclear Information System (INIS)

    Rijk, P.J.; Van Loo, S.; Webb, R.

    1996-06-01

    The feasibility of the title plant is determined for district heating and electricity supply of more than 1,000 houses in Groningen, Netherlands. Also attention is paid to the feasibility of such installations in a planned area of the city. Prices and supply of several biomass resources are dealt with: prunings of parks, public and private gardens, clean wood wastes, wood wastes from forests, wood from newly planted forests, specific energy crops (willows in high densities and short cycles). Prices are calculated, including transport to the gate of the premises where the cogeneration installations is situated. For the conversion attention is paid to both the feasibility of the use of a conventional cogeneration installation (by means of a steam turbine) and the use of a new conversion technique: combined cycle of a gasification installation and a cogeneration installation. 5 figs., 5 ills., 22 tabs., 1 appendix, 33 refs

  10. Techno-economic evaluation of commercial cogeneration plants for small and medium size companies in the Italian industrial and service sector

    International Nuclear Information System (INIS)

    Armanasco, Fabio; Colombo, Luigi Pietro Maria; Lucchini, Andrea; Rossetti, Andrea

    2012-01-01

    The liberalization of the electricity market and the concern for energy efficiency have resulted in a surge of interest in cogeneration and distributed power generation. In this regard, companies are encouraged to evaluate the opportunity to build their own cogeneration plant. In Italy, the majority of such companies belong to the industrial or service sector; it is small or medium in size and the electric power ranges between 1 ÷ 10 MW. Commercially available gas turbines are the less expensive option for cogeneration. Particular attention has been given to the possibility of combining an organic Rankine cycle (ORC) with gas turbine, to improve the conversion efficiency. Companies have to account for both technical and economical aspects to assess viability of cogeneration. A techno-economic analysis was performed to identify, in the Italian energy market, which users can take advantage of a cogeneration plant aimed to cover at least part of their energy demand. Since electricity and thermal needs change considerably in the same sector, single product categories have been considered in the analysis. Our work shows that in the industrial sector, independent of the product category, cogeneration is a viable option form a techno-economic perspective. - Highlights: ► The best technologies for 1 ÷ 10 MW distributed generation plant are gas turbine and ORC. ► A variety of commercial cogeneration plants is available to meet user needs. ► Cogeneration is a technical and economical advantage for industrial sector companies.

  11. Simulation of an air conditioning absorption refrigeration system in a co-generation process combining a proton exchange membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Pilatowsky, I.; Gamboa, S.A.; Rivera, W. [Centro de Investigacion en Energia - UNAM, Temixco, Morelos (Mexico); Romero, R.J. [Centro de Investigacion en Ingenieria y Ciencias Aplicadas - UAEM, Cuernavaca, Morelos (Mexico); Isaza, C.A. [Universidad Pontificia Bolivariana, Medellin (Colombia). Instituto de Energia y Termodinamica; Sebastian, P.J. [Centro de Investigacion en Energia - UNAM, Temixco, Morelos (Mexico); Cuerpo Academico de Energia y Sustentabilidad-UP Chiapas, Tuxtla Gutierrez, Chiapas (Mexico); Moreira, J. [Cuerpo Academico de Energia y Sustentabilidad-UP Chiapas, Tuxtla Gutierrez, Chiapas (Mexico)

    2007-10-15

    In this work, a computer simulation program was developed to determine the optimum operating conditions of an air conditioning system during the co-generation process. A 1 kW PEMFC was considered in this study with a chemical/electrical theoretical efficiency of 40% and a thermal efficiency of 30% applying an electrical load of 100%. A refrigeration-absorption cycle (RAC) operating with monomethylamine-water solutions (MMA-WS), with low vapor generation temperatures (up to 80 C) is proposed in this work. The computer simulation was based on the refrigeration production capacity at the maximum power capacity of the PEMFC. Heat losses between the fuel cell and the absorption air conditioning system at standard operating conditions were considered to be negligible. The results showed the feasibility of using PEMFC for cooling, increasing the total efficiency of the fuel cell system. (author)

  12. Biomass cogeneration: A business assessment

    Science.gov (United States)

    Skelton, J. C.

    1981-11-01

    The biomass cogeneration was reviewed. The business assessment is based in part on discussions with key officials from firms that have adopted biomass cogeneration systems and from organizations such as utilities, state and federal agencies, and banks directly involved in a biomass cogeneration project. The guide is organized into five chapters: biomass cogeneration systems, biomass cogeneration business considerations, biomass cogeneration economics, biomass cogeneration project planning, and case studies.

  13. Rocket Based Combined Cycle (RBCC) Engine

    Science.gov (United States)

    2004-01-01

    Pictured is an artist's concept of the Rocket Based Combined Cycle (RBCC) launch. The RBCC's overall objective is to provide a technology test bed to investigate critical technologies associated with opperational usage of these engines. The program will focus on near term technologies that can be leveraged to ultimately serve as the near term basis for Two Stage to Orbit (TSTO) air breathing propulsions systems and ultimately a Single Stage To Orbit (SSTO) air breathing propulsion system.

  14. High performance integrated solar combined cycles with minimum modifications to the combined cycle power plant design

    International Nuclear Information System (INIS)

    Manente, Giovanni

    2016-01-01

    Highlights: • Off-design model of a 390 MW_e three pressure combined cycle developed and validated. • The off-design model is used to evaluate different hybridization schemes with solar. • Power boosting and fuel saving with different design modifications are considered. • Maximum solar share of total electricity is only 1% with the existing equipment. • The maximum incremental solar radiation-to-electrical efficiency approaches 29%. - Abstract: The integration of solar energy into natural gas combined cycles has been successfully demonstrated in several integrated solar combined cycles since the beginning of this decade in many countries. There are many motivations that drive investments on integrated solar combined cycles which are primarily the repowering of existing power plants, the compliance with more severe environmental laws on emissions and the mitigation of risks associated with large solar projects. Integrated solar combined cycles are usually developed as brownfield facilities by retrofitting existing natural gas combined cycles and keeping the existing equipment to minimize costs. In this work a detailed off-design model of a 390 MW_e three pressure level natural gas combined cycle is built to evaluate different integration schemes of solar energy which either keep the equipment of the combined cycle unchanged or include new equipment (steam turbine, heat recovery steam generator). Both power boosting and fuel saving operation strategies are analyzed in the search for the highest annual efficiency and solar share. Results show that the maximum incremental power output from solar at design solar irradiance is limited to 19 MW_e without modifications to the existing equipment. Higher values are attainable only including a larger steam turbine. High solar radiation-to-electrical efficiencies in the range 24–29% can be achieved in the integrated solar combined cycle depending on solar share and extension of tube banks in the heat recovery

  15. Feasibility study on combined use of residential SOFC cogeneration system and plug-in hybrid electric vehicle from energy-saving viewpoint

    International Nuclear Information System (INIS)

    Wakui, Tetsuya; Wada, Naohiro; Yokoyama, Ryohei

    2012-01-01

    Highlights: ► Optimal operational planning for combined use of SOFC-CGS and PHEV is conducted. ► Charging PHEV with SOFC-CGS increases electric capacity factor of SOFC-CGS. ► Energy-saving effect of combined use is higher than that of their separate use. ► Combined use provides energy savings in both residential and transport sectors. - Abstract: The energy-saving effect of a combined use of a residential solid oxide fuel cell cogeneration system (SOFC-CGS) that adopts a continuous operation, and a plug-in hybrid electric vehicle (PHEV) is discussed by optimal operational planning based on mixed-integer linear programming. This combined use aims to increase the electric capacity factor of the SOFC-CGS by charging the PHEV using the SOFC-CGS electric power output late at night, and targets the application in regions where the reverse power flow from residential cogeneration systems to commercial electric power systems is not permitted, like in Japan. The optimal operation patterns of the combined use of 0.7-kWe SOFC-CGS and PHEV for a simulated energy demand with a sampling time of 1 h and various daily running distances of the PHEV show that this combined use increases the electric capacity factor of the SOFC-CGS and saves more energy in comparison with their separate use in which the SOFC-CGS is used but the PHEV is charged only with purchased electric power. Furthermore, it is found that at the PHEV daily running distance of 12 km/d, the reduction rate of the annual primary energy consumption for this combined use increases by up to 3.7 percentage points relative to their separate use. Consequently, this feasibility study reveals that the combined use of the SOFC-CGS and PHEV provides the synergistic effect on energy savings in the residential and transport sectors. For the practical use, simulation scenarios considering the energy demand fluctuations with short periods and real-time pricing of the purchased electric power must be considered as future

  16. Modeling of a combined cycle power plant

    International Nuclear Information System (INIS)

    Faridah Mohamad Idris

    2001-01-01

    The combined cycle power plant is a non-linear, closed loop system, which consists of high-pressure (HP) superheater, HP evaporator, HP economizer, low-pressure (LP) evaporator, HP drum, HP deaerator, condenser, HP and LP steam turbine and gas turbine. The two types of turbines in the plant for example the gas turbine and the HP and LP steam turbines operate concurrently to generate power to the plant. The exhaust gas which originate from the combustion chamber drives the gas turbine, after which it flows into the heat recovery steam generator (HRSG) to generate superheated steam to be used in driving the HP and LP steam turbines. In this thesis, the combined cycle power plant is modeled at component level using the physical method. Assuming that there is delay in transport, except for the gas turbine system, the mass and heat balances are applied on the components of the plant to derive the governing equations of the components. These time dependent equations, which are of first order differential types, are then solved for the mass and enthalpy of the components. The solutions were simulated using Matlab Simulink using measured plant data. Where necessary there is no plant data available, approximated data were used. The generalized regression neural networks are also used to generate extra sets of simulation data for the HRSG system. Comparisons of the simulation results with its corresponding plant data showed good agreements between the two and indicated that the models developed for the components could be used to represent the combined cycle power plant under study. (author)

  17. Combined cycle plant controls retrofit case history

    International Nuclear Information System (INIS)

    Tenney, D.; Pieszchala, T.

    1991-01-01

    The Comanche Power Station, Public Service of Oklahoma's combined cycle generating facility, underwent a controls and operator panel retrofit at the end of 1988. The plant consists of two gas turbines, two heat recovery boilers and a steam turbine along with three generators. This paper examines the extent to which the original goals and specifications were met. Costs, operating principles and modifications since the original installation are discussed. Operating procedures are compared with the original system. The future of the plant is discussed and the impact on the power system grid is analyzed

  18. Optimal energy exchange of an industrial cogeneration in a day-ahead electricity market

    International Nuclear Information System (INIS)

    Yusta, J.M.; De Oliveira-De Jesus, P.M.; Khodr, H.M.

    2008-01-01

    This paper addresses an optimal strategy for the daily energy exchange of a 22-MW combined-cycle cogeneration plant of an industrial factory operating in a liberalized electricity market. The optimization problem is formulated as a Mixed-Integer Linear Programming Problem (MILP) that maximizes the profit from energy exchange of the cogeneration, and is subject to the technical constraints and the industrial demand profile. The integer variables are associated with export or import of electricity whereas the real variables relate to the power output of gas and steam turbines, and to the electricity purchased from or sold to the market. The proposal is applied to a real cogeneration plant in Spain where the detailed cost function of the process is obtained. The problem is solved using a large-scale commercial package and the results are discussed and compared with different predefined scheduling strategies. (author)

  19. Introduction to cogeneration; Introducao a cogeracao

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, Luiz Augusto Horta; Martins, Andre Luiz Silva [Escola Federal de Engenharia de Itajuba, MG (Brazil)

    1997-07-01

    This work presents a general view of cogeneration. The paper approaches the development of cogeneration, technological aspects, the cogeneration in Brazil, economical aspects, performance of cogeneration systems, viability, costs, cogeneration potentials and technological trends.

  20. Cogeneration in Taiwan

    Energy Technology Data Exchange (ETDEWEB)

    Cotard, E. [International Cogeneration Alliance (United States)

    2000-10-01

    The short article discusses pollution abatement and the potential role of cogeneration in Taiwan. A diagram shows the contributions of various energy sources (coal, oil etc.) from 1979-1999 and the growth of cogeneration between 1979 and 1999. The lack of natural gas or diesel does not help the cause of cogeneration in Taiwan, nor does the structure of the local electricity market. Nevertheless, if the proposed new LNG facilities are built in the North, then the opportunities for cogeneration will be very good.

  1. Methodology for the optimal design of an integrated first and second generation ethanol production plant combined with power cogeneration.

    Science.gov (United States)

    Bechara, Rami; Gomez, Adrien; Saint-Antonin, Valérie; Schweitzer, Jean-Marc; Maréchal, François

    2016-08-01

    The application of methodologies for the optimal design of integrated processes has seen increased interest in literature. This article builds on previous works and applies a systematic methodology to an integrated first and second generation ethanol production plant with power cogeneration. The methodology breaks into process simulation, heat integration, thermo-economic evaluation, exergy efficiency vs. capital costs, multi-variable, evolutionary optimization, and process selection via profitability maximization. Optimization generated Pareto solutions with exergy efficiency ranging between 39.2% and 44.4% and capital costs from 210M$ to 390M$. The Net Present Value was positive for only two scenarios and for low efficiency, low hydrolysis points. The minimum cellulosic ethanol selling price was sought to obtain a maximum NPV of zero for high efficiency, high hydrolysis alternatives. The obtained optimal configuration presented maximum exergy efficiency, hydrolyzed bagasse fraction, capital costs and ethanol production rate, and minimum cooling water consumption and power production rate. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. An estimation of cogeneration potential by using refinery residuals in Mexico

    International Nuclear Information System (INIS)

    Marin-Sanchez, J.E.; Rodriguez-Toral, M.A.

    2007-01-01

    Electric power generation in Mexico is mainly based on fossil fuels, specifically heavy fuel oil, although the use of natural gas combined cycles (NGCC) is becoming increasingly important. This is the main destination that has promoted growing imports of natural gas, currently accounting for about 20% of the total national annual consumption. Available crude oil is becoming heavier; thus refineries should be able to process it, and to handle greater quantities of refinery residuals. If all refinery residuals are used in cogeneration plants serving petroleum refineries, the high heat/power ratio of refinery needs, leads to the availability of appreciable quantities of electricity that can be exported to the public utility. Thus, in a global perspective, Mexican imports of natural gas may be reduced by cogeneration using refinery residuals. This is not the authors' idea; in fact, PEMEX, the national oil company, has been entitled by the Mexican congress to sell its power leftovers to The Federal Electricity Commission (CFE) in order to use cogeneration in the way described for the years to come. A systematic way of determining the cogeneration potential by using refinery residuals from Mexican refineries is presented here, taking into account residual quantities and composition, from a national perspective, considering expected scenarios for Maya crude content going to local refineries in the years to come. Among different available technologies for cogeneration using refinery residuals, it is believed that the integrated gasification combined cycle (IGCC) would be the best option. Thus, considering IGCC plants supplying heat and power to refineries where it is projected to have refinery residuals for cogeneration, the expected electric power that can be sent to the public utility is quantified, along with the natural gas imports mitigation that may be attained. This in turn would contribute to a necessary fuel diversification policy balancing energy, economy and

  3. Cogeneration based on gasified biomass - a comparison of concepts

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Fredrik

    1999-01-01

    In this report, integration of drying and gasification of biomass into cogeneration power plants, comprising gas turbines, is investigated. The thermodynamic cycles considered are the combined cycle and the humid air turbine cycle. These are combined with either pressurised or near atmospheric gasification, and steam or exhaust gas dryer, in a number of combinations. An effort is made to facilitate a comparison of the different concepts by using, and presenting, similar assumptions and input data for all studied systems. The resulting systems are modelled using the software package ASPEN PLUS{sup TM}, and for each system both the electrical efficiency and the fuel utilisation are calculated. The investigation of integrated gasification combined cycles (IGCC), reveals that systems with pressurised gasification have a potential for electrical efficiencies approaching 45% (LHV). That is 4 - 5 percentage points higher than the corresponding systems with near atmospheric gasification. The type of dryer in the system mainly influences the fuel utilisation, with an advantage of approximately 8 percentage points (LHV) for the steam dryer. The resulting values of fuel utilisation for the IGCC systems are in the range of 78 - 94% (LHV). The results for the integrated gasification humid air turbine systems (IGHAT) indicate that electrical efficiencies close to the IGCC are achievable, provided combustion of the fuel gas in highly humidified air is feasible. Reaching a high fuel utilisation is more difficult for this concept, unless the temperature levels in the district heating network are low. For comparison a conventional cogeneration plant, based on a CFB boiler and a steam turbine (Rankine cycle), is also modelled in ASPEN PLUS{sup TM}. The IGCC and IGHAT show electrical efficiencies in the range of 37 - 45% (LHV), compared with a calculated value of 31% (LHV) for the Rankine cycle cogeneration plant. Apart from the electrical efficiency, also a high value of fuel

  4. Cogeneration steam turbines from Siemens: New solutions

    Science.gov (United States)

    Kasilov, V. F.; Kholodkov, S. V.

    2017-03-01

    The Enhanced Platform system intended for the design and manufacture of Siemens AG turbines is presented. It combines organizational and production measures allowing the production of various types of steam-turbine units with a power of up to 250 MWel from standard components. The Enhanced Platform designs feature higher efficiency, improved reliability, better flexibility, longer overhaul intervals, and lower production costs. The design features of SST-700 and SST-900 steam turbines are outlined. The SST-700 turbine is used in backpressure steam-turbine units (STU) or as a high-pressure cylinder in a two-cylinder condensing turbine with steam reheat. The design of an SST-700 single-cylinder turbine with a casing without horizontal split featuring better flexibility of the turbine unit is presented. An SST-900 turbine can be used as a combined IP and LP cylinder (IPLPC) in steam-turbine or combined-cycle power units with steam reheat. The arrangements of a turbine unit based on a combination of SST-700 and SST-900 turbines or SST-500 and SST-800 turbines are presented. Examples of this combination include, respectively, PGU-410 combinedcycle units (CCU) with a condensing turbine and PGU-420 CCUs with a cogeneration turbine. The main equipment items of a PGU-410 CCU comprise an SGT5-4000F gas-turbine unit (GTU) and STU consisting of SST-700 and SST-900RH steam turbines. The steam-turbine section of a PGU-420 cogeneration power unit has a single-shaft turbine unit with two SST-800 turbines and one SST-500 turbine giving a power output of N el. STU = 150 MW under condensing conditions.

  5. The cogeneration in France

    International Nuclear Information System (INIS)

    2006-01-01

    Since the years 90 many measures have been decided by the government in favor of the cogeneration, to implement a juridical, fiscal, technical and economical framework. After a presentation of the three main channels and the advantages of the cogeneration, the author presents these measures. (A.L.B.)

  6. Analysis of a combined Rankine-vapour-compression refrigeration cycle

    International Nuclear Information System (INIS)

    Aphornratana, Satha; Sriveerakul, Thanarath

    2010-01-01

    This paper describes a theoretical analysis of a heat-powered refrigeration cycle, a combined Rankine-vapour-compression refrigeration cycle. This refrigeration cycle combines an Organic Rankine Cycle and a vapour-compression cycle. The cycle can be powered by low grade thermal energy as low as 60 deg. C and can produce cooling temperature as low as -10 deg. C. In the analysis, two combined Rankine-vapour-compression refrigeration cycles were investigated: the system with R22 and the system with R134a. Calculated COP values between 0.1 and 0.6 of both the systems were found.

  7. Combined use of solar heat and cogeneration - a perspective for district heating?; Kombinierter Einsatz von solarer Waerme und Kraft-Waerme-Kopplung - eine Perspektive fuer die Nahwaerme?

    Energy Technology Data Exchange (ETDEWEB)

    Entress, J. [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR), Stuttgart (Germany). Abt. Systemanalyse und Technikbewertung; Steinborn, F. [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany). Fachgebiet Systemanalyse

    1998-02-01

    With Cogeneration of Heat and Power (CHP), climate-endangering CO{sub 2}-emissions can be reduced singificantly. The heat produced can be delivered at prices comparable to those of conventionally produced heat. With solar district heating, yet higher CO{sub 2}-savings are possible but at higher cost. Promising is a combination of CHP and solar district heating: The heat storage of the solar system can be used to level out heat demand, leading to smooth CHP operation, while heat generated by CHP can be used to substitute for low irradiation during the winter period. However, calculations together with simulation and optimization indicate that combining CHP and solar district heating is not the optimal solution in all cases. (orig.) [Deutsch] Der Einsatz von Blockheizkraftwerken (BHKW) kann zu einer deutlichen Reduzierung der klimagefaehrdenden CO{sub 2}-Emissionen beitragen. Dabei kann die ausgekoppelte Waerme etwa zum gleichen Preis wie konventionell erzeugte Waerme abgegeben werden. Hoehere CO{sub 2}-Einsparungen lassen sich hingegen mit solarer Nahwaerme erzielen, allerdings zu hoeheren Kosten. Eine Kombination dieser beiden Waermetechniken verspricht Vorteile: Einerseits kann der Waermespeicher des Solarsystems auch zum Ausgleich von Lastspitzen beim Betrieb des BHKW`s genutzt werden. Andererseits kann die waehrend der einstrahlungsarmen Wintermonate fehlende solare Waerme durch das BHKW erzeugt werden. Detaillierte Simulations- und Optimierungsrechnungen zeigen jedoch, dass eine Kombination dieser Waermetechniken nicht immer empfehlenswert ist. (orig.)

  8. Extra cogeneration step seen boosting output 20%

    Energy Technology Data Exchange (ETDEWEB)

    Burton, P.

    1984-10-08

    Cogenerators can now buy a prototype 6.5 MW, pre-packaged cogeneration system that incorporates an added step to its cycle to reduce fuel use by 21%. Larger, custom-designed systems will be on the market in 1985. Fayette Manufacturing Co. will offer the Kalina Cycle system at a discount price of $8.2 million (1200/kW) until the systems are competitive with conventional units. The system varies from conventional cogeneration systems by adding a distillation step, which permits the use of two fluids for the turbine steam and operates at a higher thermodynamic efficiency, with boiling occuring at high temperature and low pressure. Although theoretically correct, DOE will withhold judgment on the system's efficiency until the first installation is operating.

  9. Proposal of a combined heat and power plant hybridized with regeneration organic Rankine cycle: Energy-Exergy evaluation

    International Nuclear Information System (INIS)

    Anvari, Simin; Jafarmadar, Samad; Khalilarya, Shahram

    2016-01-01

    Highlights: • A new thermodynamic cogeneration system is proposed. • Energy and exergy analysis of the considered cycle were performed. • An enhancement of 2.6% in exergy efficiency compared to that of baseline cycle. - Abstract: Among Rankine cycles (simple, reheat and regeneration), regeneration organic Rankine cycle demonstrates higher efficiencies compared to other cases. Consequently, in the present work a regeneration organic Rankine cycle has been utilized to recuperate gas turbine’s heat using heat recovery steam generator. At first, this cogeneration system was subjected to energy and exergy analysis and the obtained results were compared with that of investigated cogeneration found in literature (a cogeneration system in which a reheat organic Rankine cycle for heat recuperation of gas turbine cycle was used with the aid of heat recovery steam generator). Results indicated that the first and second thermodynamic efficiencies in present cycle utilizing regeneration cycle instead of reheat cycle has increased 2.62% and 2.6%, respectively. In addition, the effect of thermodynamic parameters such as combustion chamber’s inlet temperature, gas turbine inlet temperature, evaporator and condenser temperature on the energetic and exergetic efficiencies of gas turbine-heat recovery steam generator cycle and gas turbine-heat recovery steam generator cycle with regeneration organic Rankine cycle was surveyed. Besides, parametric analysis shows that as gas turbine and combustion chamber inlet temperatures increase, energetic and exergetic efficiencies tend to increase. Moreover, once condenser and evaporator temperature raise, a slight decrement in energetic and exergetic efficiency is expected.

  10. AMBIENT CONDITIONS EFFECTS ON PERFORMANCE OF GAS TURBINE COGENERATION POWER PLANTS

    OpenAIRE

    Necmi Ozdemir*

    2016-01-01

    In this study, the performances of a simple and an air preheated cogeneration cycles in ambient conditions are compared with each other. A computer program written by the author in FORTRAN codes is used for the calculation of the enthalpy and entropy values of the streams, Exergy analysis is done and compared for the simple and the air preheated cogeneration cycles for different ambient conditions. The two cogeneration cycles are evaluated in terms of heat powers and electric, electrical to h...

  11. Cogeneration in air separation cryogenic plants; Cogeracao em plantas criogenicas de separacao de ar

    Energy Technology Data Exchange (ETDEWEB)

    Bastos, Walter N.; Orlando, Alcir F. [Pontificia Univ. Catolica do Rio de Janeiro, RJ (Brazil). Dept. de Engenharia Mecanica]. E-mails: wnovellob@openlink.com.br; afo@mec-puc-rio.br

    2000-07-01

    A thermal and economic study, carried on by using the first and second law of thermodynamics concepts demonstrated the economic feasibility of the cogeneration system, and proposed modifications to be done in the studied cryogenic plant, a typical T-240 NA MPL3 plant. The thermodynamic analysis showed that the second law efficiency of the processes could be improved, together with a 12% electric energy consumption reduction. Four cogeneration schemes were analyzed with both the first and second laws of thermodynamics and, then, the economic analysis was performed. Rankine, Brayton, Otto and Combined gas-steam basic cycles were used in this analysis.The combined gas-steam cycle was shown to be more economically feasible than others. Thermal and electric loads were well balanced, resulting in a higher second law efficiency. Although the initial investment for the modification was higher, the savings resulted to be higher, turning into a higher rate of return of the investment. (author)

  12. INCOGEN: Nuclear cogeneration in the Netherlands

    International Nuclear Information System (INIS)

    Heek, A.I. van

    1997-01-01

    A small heat and power cogeneration plant with a pebble bed high temperature reactor (HTR) is discussed. Cogeneration could be a new market for nuclear power and the HTR could be very suitable. The 40 MWth INCOGEN system is presented. Philosophy, layout, characteristics and performance are described. The lower power level, advanced component technologies and inherent safety features are used to obtain a maximally simplified system. Static and dynamic cycle analyses of the energy conversion system are discussed, as well as the behaviour of the reactor cavity cooling system. Although the cost study has not been finished yet, cost reduction trends are indicated. (author)

  13. Duct burners in heat recovery system for cogeneration and captive power plants

    International Nuclear Information System (INIS)

    Majumdar, J.

    1992-01-01

    Our oil explorations both onshore and offshore have thrown open bright prospects of cogeneration by using natural gas in gas turbine power plants with heat recovery units. Both for co-gen and combined cycle systems, supplementary firing of GT exhaust gas is normally required. Hence, duct burners have significant role for effective contribution towards of efficacy of heat recovery system for gas turbine exhaust gas. This article details on various aspects of duct burners in heat recovery systems. (author)

  14. Cogeneration markets in Ontario

    International Nuclear Information System (INIS)

    Poredos, S.

    1993-01-01

    Cogeneration offers a key strategy which supports global competitiveness for Ontario businesses, encourages energy efficiency and environmental protection, and offers natural gas utilities and producers stable long-term incremental markets. By supporting cogeneration projects, electric utilities will benefit from increased flexibility. Natural gas is the fuel of choice for cogeneration, which can in most cases be easily integrated into existing operations. In Ontario, electric demand grew along with the gross domestic product until 1990, but has decreased with the recent economic recession. The provincial utility Ontario Hydro is resizing itself to stabilize total rate increases of 30% over the last three years and supporting reduction of its high debt load. Rate increases are supposed to be limited but this may be difficult to achieve without further cost-cutting measures. Cogeneration opportunities exist with many institutional and industrial customers who are trying to remain globally competitive by cutting operating costs. In general, cogeneration can save 20% or more of total annual energy costs. Due to excess capacity, Ontario Hydro is not willing to purchase electric power, thus only electric load displacement projects are valid at this time. This will reduce overall savings due to economies of scale. In southwestern Ontario, Union Gas Ltd. has been successful in developing 40 MW of electric displacement projects, providing a total load of 5 billion ft 3 of natural gas (50% of which is incremental). Over 3,000 MW of technical cogeneration potential is estimated to exist in the Union Gas franchise area

  15. Global environment and cogeneration

    International Nuclear Information System (INIS)

    Miyahara, Atsushi

    1992-01-01

    The environment problems on global scale have been highlighted in addition to the local problems due to the rapid increase of population, the increase of energy demand and so on. The global environment summit was held in Brazil. Now, global environment problems are the problems for mankind, and their importance seems to increase toward 21st century. In such circumstances, cogeneration can reduce carbon dioxide emission in addition to energy conservation, therefore, attention has been paid as the countermeasure for global environment. The background of global environment problems is explained. As to the effectiveness of cogeneration for global environment, the suitability of city gas to environment, energy conservation, the reduction of carbon dioxide and nitrogen oxides emission are discussed. As for the state of spread of cogeneration, as of March, 1992, those of 2250 MW in terms of power generation capacity have been installed in Japan. It is forecast that cogeneration will increase hereafter. As the future systems of cogeneration, city and industry energy center conception, industrial repowering, multiple house cogeneration and fuel cells are described. (K.I.)

  16. The future of integrated coal gasification combined cycle power plants

    International Nuclear Information System (INIS)

    Mueller, R.; Termuehlen, H.

    1991-01-01

    This paper examines the future of integrated coal gasification combined cycle (IGCC) power plants as affected by various technical, economical and environmental trends in power generation. The topics of the paper include a description of natural gas-fired combined cycle power plants, IGCC plants, coal gasifier concepts, integration of gasifiers into combined cycle power plants, efficiency, environmental impacts, co-products of IGCC power plants, economics of IGCC power plants, and a review of IGCC power plant projects

  17. Technical comparison between Integrated Gasification Combined Cycle (IGCC) and Natural Gas Combined Cycle (NGCC) power plants

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz, Pablo Andres Silva; Venturini, Osvaldo Jose; Lora, Electo Eduardo Silva [Federal University of Itajuba - UNIFEI, MG (Brazil). Excellence Group in Thermal Power and Distributed Generation - NEST], e-mails: osvaldo@unifei.edu.br, electo@unifei.edu.br

    2010-07-01

    Among the emerging clean coal technologies for power generation, Integrated Gasification Combined Cycle (IGCC) and Natural Gas Combined Cycle (NGCC) systems are receiving considerable attention as a potentially attractive option to reduce the emissions of greenhouse gases (GHG). The main reason is because these systems has high efficiency and low emissions in comparison with traditional power generation plants. Currently in IGCC and NGCC systems at demonstration stage is been considered to implement CCS technology. CO{sub 2} emissions can be avoided in a gasification-based power plant because by transferring almost all carbon compounds to CO{sub 2} through the water gas shift (WGS) reaction, then removing the CO{sub 2} before it is diluted in the combustion stage. The aim of this study is to compare the technical performance of an IGCC system that uses Brazilian coal and petroleum coke as fuel with a NGCC system, with the same fixed output power of 450 MW. The first section of this paper presents the plant configurations of IGCC systems. The following section presents an analysis of NGCC technology. (author)

  18. The California cogeneration success story

    International Nuclear Information System (INIS)

    Neiggemann, M.F.

    1992-01-01

    This chapter describes the involvement of Southern California Gas Company(SoCalGas) in the promotion and demonstration of the benefits of cogeneration in California. The topics covered in this chapter are market strategy, cogeneration program objectives, cogeneration program, incentive cofunding, special gas rate, special service priority, special gas pressure and main options, advertising, promotional brochures and handbooks, technical support, program accomplishments, cogeneration outlook, and reasons for success of the program

  19. Gas cogeneration system in Sapporo Therme

    Energy Technology Data Exchange (ETDEWEB)

    Kanematsu, Michihiko

    1988-06-01

    Sapporo Therme is a multi-purpose resort including a hot-water jumbo swimming pool having an area of about 130,000m/sup 2/ and a circumference of 800 m, 13 additional swimming pools with additional sizes, a hot-water slider, 16 types of saunas, an artificial sunbathing system, an athletic system, a restaurant, a cinema, tennis courts, and other outdoor facilities. Sapporo Therme uses a cogeneration system consisting of using LP gas(95% or more propane gas) to drive a 1,200 PS gas engine and supply motive power and lightening. At the same time, the cogeneration system collects gas engine waste heat and combines this heat with that from hot-water and steam boilers to supply hot water to swimming pools, roads, and room heaters. The ratio of waste heat collection rate to power generation efficiency is about 5.0. Sapporo Therme is thus the optimal facilities for cogeneration. (1 figs, 3 photos)

  20. Cogeneration an opportunity for industrial energy saving

    International Nuclear Information System (INIS)

    Pasha, R.A.; Butt, Z.S.

    2011-01-01

    This paper is about the cogeneration from industrial energy savings opportunities perspective. The energy crisis in these days forces industry to find ways to cope with critical situation. There are several energy savings options which if properly planned and implemented would be beneficial both for industry and community. One way of energy saving is Cogeneration i.e. Combined Heat and Power. The paper will review the basic methods, types and then discuss the suitability of these options for specific industry. It has been identified that generally process industry can get benefits of energy savings. (author)

  1. Energy and Exergy Analyses of a New Combined Cycle for Producing Electricity and Desalinated Water Using Geothermal Energy

    Directory of Open Access Journals (Sweden)

    Mehri Akbari

    2014-04-01

    Full Text Available A new combined cogeneration system for producing electrical power and pure water is proposed and analyzed from the viewpoints of thermodynamics and economics. The system uses geothermal energy as a heat source and consists of a Kalina cycle, a LiBr/H2O heat transformer and a water purification system. A parametric study is carried out in order to investigate the effects on system performance of the turbine inlet pressure and the evaporator exit temperature. For the proposed system, the first and second law efficiencies are found to be in the ranges of 16%–18.2% and 61.9%–69.1%, respectively. For a geothermal water stream with a mass flow rate of 89 kg/s and a temperature of 124 °C, the maximum production rate for pure water is found to be 0.367 kg/s.

  2. Cogeneration. Energy efficiency - Micro-cogeneration; La Cogeneration. Efficacite Energetique - Micro-cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Boudellal, M.

    2010-07-01

    Depletion of natural resources and of non-renewable energy sources, pollution, greenhouse effect, increasing energy needs: energy efficiency is a major topic implying a better use of the available primary energies. In front of these challenges, cogeneration - i.e. the joint production of electricity and heat, and, at a local or individual scale, micro-cogeneration - can appear as interesting alternatives. This book presents in a detailed manner: the present day and future energy stakes; the different types of micro-cogeneration units (internal combustion engines, Stirling engine, fuel cell..), and the available models or the models at the design stage; the different usable fuels (natural gas, wood, biogas..); the optimization rules of a facility; the costs and amortizations; and some examples of facilities. (J.S.)

  3. Thermionic cogeneration burner design

    Science.gov (United States)

    Miskolczy, G.; Goodale, D.; Moffat, A. L.; Morgan, D. T.

    Since thermionic converters receive heat at very high temperatures (approximately 1800 K) and reject heat at moderately high temperatures (approximately 800 K), they are useful for cogeneration applications involving high temperature processes. The electric power from thermionic converters is produced as a high amperage, low-voltage direct current. An ideal cogeneration application would be to utilize the reject heat at the collector temperature and the electricity without power conditioning. A cogeneration application in the edible oil industry fulfills both of these requirements since both direct heat and hydrogen gas are required in the hydrogenation of the oils. In this application, the low-voltage direct current would be used in a hydrogen electrolyzer.

  4. Hybrid cycles for micro generation

    International Nuclear Information System (INIS)

    Campanari, S.

    2000-01-01

    This paper deals with the main features of two emerging technologies in the field of small-scale power generation, micro turbines and Solid Oxide Fuel Cells, discussing the extremely high potential of their combination into hybrid cycles and their possible role for distributed cogeneration [it

  5. [Combined hormonal contraception in cycles artificially extended].

    Science.gov (United States)

    Bustillos-Alamilla, Edgardo; Zepeda-Zaragoza, J; Hernández-Ruiz, M A; Briones-Landa, Carlos Humberto

    2010-01-01

    To compare the bleeding patterns, satisfaction and tolerability of 3 different contraceptive in an extended regimens in the service of Family Planning of the North Central Hospital of PEMEX. Healthy, adult women with desire of contraception for one year (N 120) were randomly assigned to receive oral contraceptive drospirenone/ethinyl E2 (group1), the norelgestromin/ethinyl E2 transdermal patch (group 2) and vaginal ring etonogestrel/ ethinyl E2 (group 3) in an extended regimen (42 consecutive days, 1 hormone-free week). Study assessments were conducted at scheduled visits at the time of initial screening, at baseline after 1, 3, 6, and 12 months. Subjects recorded menstrual associated symptoms bleeding data and completed satisfaction questionnaires. Subjects and investigators provided overall assessments of the regimens. Extended use of 3 different contraceptive resulted in fewer bleeding days in every group (66.6%, 55% and 58.3% P 0.0024), and less mastalgia and menstrual pain. Subjects were highly satisfied with three regimens (93.3%, 96.6% and 91.6% P 0.00421). Although not mayor adverse events were reported with this regimen, there was an increase in spotting days; it decreased with each successive cycle of therapy. Efficacy and safety were similar to those reported for traditional cycle. Extended-contraceptive regimen delays menses and reduces bleeding, a profile that may be preferred by women who seek flexibility with their contraceptive method.

  6. Variable geometry gas turbines for improving the part-load performance of marine combined cycles - Combined cycle performance

    DEFF Research Database (Denmark)

    Haglind, Fredrik

    2011-01-01

    The part-load performance of combined cycles intended for naval use is of great importance, and it is influenced by the gas turbine configuration and load control strategy. This paper is aimed at quantifying the effects of variable geometry gas turbines on the part-load efficiency for combined...... cycles used for ship propulsion. Moreover, the paper is aimed at developing methodologies and deriving models for part-load simulations suitable for energy system analysis of various components within combined cycle power plants. Two different gas turbine configurations are studied, a two-shaft aero......-derivative configuration and a single-shaft industrial configuration. The results suggest that by the use of variable geometry gas turbines, the combined cycle part-load performance can be improved. In order to minimise the voyage fuel consumption, a combined cycle featuring two-shaft gas turbines with VAN control...

  7. Exergy-based method for analyzing the composition of the electricity cost generated in gas-fired combined cycle plants

    Energy Technology Data Exchange (ETDEWEB)

    Sarraf Borelli, Samuel Jose [Promon Engenharia Ltda., Av. Presidente Juscelino Kubitschek, 1830, Itaim, CEP:04543-900 Sao Paulo/SP (Brazil)], E-mail: sborelli@terra.com.br; Oliveira Junior, Silvio de [Environmental and Thermal Engineering Laboratory, Polytechnic School, University of Sao Paulo, Av. Prof. Luciano Gualberto, 1289, Cidade Universitaria, CEP:05508-900 Sao Paulo/SP (Brazil)], E-mail: silvio.oliveira@poli.usp.br

    2008-02-15

    The proposed method to analyze the composition of the cost of electricity is based on the energy conversion processes and the destruction of the exergy through the several thermodynamic processes that comprise a combined cycle power plant. The method uses thermoeconomics to evaluate and allocate the cost of exergy throughout the processes, considering costs related to inputs and investment in equipment. Although the concept may be applied to any combined cycle or cogeneration plant, this work develops only the mathematical modeling for three-pressure heat recovery steam generator (HRSG) configurations and total condensation of the produced steam. It is possible to study any nx1 plant configuration (n sets of gas turbine and HRSGs associated to one steam turbine generator and condenser) with the developed model, assuming that every train operates identically and in steady state. The presented model was conceived from a complex configuration of a real power plant, over which variations may be applied in order to adapt it to a defined configuration under study [Borelli SJS. Method for the analysis of the composition of electricity costs in combined cycle thermoelectric power plants. Master in Energy Dissertation, Interdisciplinary Program of Energy, Institute of Eletro-technical and Energy, University of Sao Paulo, Sao Paulo, Brazil, 2005 (in Portuguese)]. The variations and adaptations include, for instance, use of reheat, supplementary firing and partial load operation. It is also possible to undertake sensitivity analysis on geometrical equipment parameters.

  8. Exergy-based method for analyzing the composition of the electricity cost generated in gas-fired combined cycle plants

    Energy Technology Data Exchange (ETDEWEB)

    Borelli, Samuel Jose Sarraf [Promon Engenharia Ltda., Av. Presidente Juscelino Kubitschek, 1830, Itaim, CEP:04543-900 Sao Paulo/SP (Brazil); De Oliveira Junior, Silvio [Environmental and Thermal Engineering Laboratory, Polytechnic School, University of Sao Paulo, Av. Prof. Luciano Gualberto, 1289, Cidade Universitaria, CEP:05508-900 Sao Paulo/SP (Brazil)

    2008-02-15

    The proposed method to analyze the composition of the cost of electricity is based on the energy conversion processes and the destruction of the exergy through the several thermodynamic processes that comprise a combined cycle power plant. The method uses thermoeconomics to evaluate and allocate the cost of exergy throughout the processes, considering costs related to inputs and investment in equipment. Although the concept may be applied to any combined cycle or cogeneration plant, this work develops only the mathematical modeling for three-pressure heat recovery steam generator (HRSG) configurations and total condensation of the produced steam. It is possible to study any n x 1 plant configuration (n sets of gas turbine and HRSGs associated to one steam turbine generator and condenser) with the developed model, assuming that every train operates identically and in steady state. The presented model was conceived from a complex configuration of a real power plant, over which variations may be applied in order to adapt it to a defined configuration under study [Borelli SJS. Method for the analysis of the composition of electricity costs in combined cycle thermoelectric power plants. Master in Energy Dissertation, Interdisciplinary Program of Energy, Institute of Eletro-technical and Energy, University of Sao Paulo, Sao Paulo, Brazil, 2005 (in Portuguese)]. The variations and adaptations include, for instance, use of reheat, supplementary firing and partial load operation. It is also possible to undertake sensitivity analysis on geometrical equipment parameters. (author)

  9. Exergy-based method for analyzing the composition of the electricity cost generated in gas-fired combined cycle plants

    International Nuclear Information System (INIS)

    Sarraf Borelli, Samuel Jose; Oliveira Junior, Silvio de

    2008-01-01

    The proposed method to analyze the composition of the cost of electricity is based on the energy conversion processes and the destruction of the exergy through the several thermodynamic processes that comprise a combined cycle power plant. The method uses thermoeconomics to evaluate and allocate the cost of exergy throughout the processes, considering costs related to inputs and investment in equipment. Although the concept may be applied to any combined cycle or cogeneration plant, this work develops only the mathematical modeling for three-pressure heat recovery steam generator (HRSG) configurations and total condensation of the produced steam. It is possible to study any nx1 plant configuration (n sets of gas turbine and HRSGs associated to one steam turbine generator and condenser) with the developed model, assuming that every train operates identically and in steady state. The presented model was conceived from a complex configuration of a real power plant, over which variations may be applied in order to adapt it to a defined configuration under study [Borelli SJS. Method for the analysis of the composition of electricity costs in combined cycle thermoelectric power plants. Master in Energy Dissertation, Interdisciplinary Program of Energy, Institute of Eletro-technical and Energy, University of Sao Paulo, Sao Paulo, Brazil, 2005 (in Portuguese)]. The variations and adaptations include, for instance, use of reheat, supplementary firing and partial load operation. It is also possible to undertake sensitivity analysis on geometrical equipment parameters

  10. Study of combined cycle engine for aerospace plane

    OpenAIRE

    苅田, 丈士; KANDA, Takeshi; 工藤, 賢司; KUDO, Kenji

    2002-01-01

    At the Ramjet Propulsion Research Center, the scramjet engine for an aerospace plane has been studied. Other engines are required for the plane to go into orbit. Recently, a combined cycle engine including scramjet mode has been also studied to complete the engine system for the plane. The scramjet and the combined cycle engine are most effective with application to the Single-Stage-to-Orbit (SSTO) aerospace plane, as shown in Figure 1. Recent activity on the combined cycle engine and the SST...

  11. Combined micro-cogeneration and electric vehicle system for household application: An energy and economic analysis in a Northern European climate

    DEFF Research Database (Denmark)

    Vialetto, Giulio; Noro, Marco; Rokni, Masoud

    2017-01-01

    -thinking of entire energy infrastructures and types of consumption. The Agenda also suggested, among other things, improving the efficiency of energy systems. In this paper, the interactions between charging an electric car and an innovative cogeneration system for household application (micro-solid oxide fuel cell...... with an integrated heating system) are investigated. The charge of the electric car by the cogenerator produces waste heat that can be used to partially cover the heat demand of the house. In this way it may be possible to increase overall efficiency and decrease total energy costs. Different innovative strategies...... are proposed and analyzed to manage charging an electric car and efficiently using the waste heat available. The aims of this study are to make the system grid-independent, to decrease the thermal stress of SOFCs and to determine the nominal power of an integrated heating system. The results show energy...

  12. Hybrid solar central receiver for combined cycle power plant

    Science.gov (United States)

    Bharathan, Desikan; Bohn, Mark S.; Williams, Thomas A.

    1995-01-01

    A hybrid combined cycle power plant including a solar central receiver for receiving solar radiation and converting it to thermal energy. The power plant includes a molten salt heat transfer medium for transferring the thermal energy to an air heater. The air heater uses the thermal energy to preheat the air from the compressor of the gas cycle. The exhaust gases from the gas cycle are directed to a steam turbine for additional energy production.

  13. Combined cycle power plants: technological prospects for improving the efficiency

    International Nuclear Information System (INIS)

    Lauri, R.

    2009-01-01

    The combined cycle power plants characteristics are better than one course open to a closed loop presenting an electrical efficiency close to 60% do not reach for gas turbine engines for power plants and conventional steam engines. [it

  14. Gasification and combined cycles: Present situation and future prospects

    International Nuclear Information System (INIS)

    Brustia, G.F.; Bressan, L.; Domenichini, R.

    1992-01-01

    The gasification of coal and/or residual fuels from refineries together with the use of combined cycle power generation systems represents a technically and economically feasible method for the conversion of poor quality fossil fuels into electric power. The conversion is accomplished with maximum respect for the severest environmental normatives. In addition, foreseen technical improvements for components and plant systems are expected to heighten the marketing potential of gasification/combined cycle power plants. After Italy's moratorium on nuclear energy, the passing eras of conventional fossil fuel and then combined cycle power plants, the need for highly competitive industrial production technologies and the urgency of nation-wide energy conservation appear to be ushering in the new era of gasification with combined cycles

  15. Gas--steam turbine combined cycle power plants

    Energy Technology Data Exchange (ETDEWEB)

    Christian, J.E.

    1978-10-01

    The purpose of this technology evaluation is to provide performance and cost characteristics of the combined gas and steam turbine, cycle system applied to an Integrated Community Energy System (ICES). To date, most of the applications of combined cycles have been for electric power generation only. The basic gas--steam turbine combined cycle consists of: (1) a gas turbine-generator set, (2) a waste-heat recovery boiler in the gas turbine exhaust stream designed to produce steam, and (3) a steam turbine acting as a bottoming cycle. Because modification of the standard steam portion of the combined cycle would be necessary to recover waste heat at a useful temperature (> 212/sup 0/F), some sacrifice in the potential conversion efficiency is necessary at this temperature. The total energy efficiency ((electric power + recovered waste heat) divided by input fuel energy) varies from about 65 to 73% at full load to 34 to 49% at 20% rated electric power output. Two major factors that must be considered when installing a gas--steam turbine combines cycle are: the realiability of the gas turbine portion of the cycle, and the availability of liquid and gas fuels or the feasibility of hooking up with a coal gasification/liquefaction process.

  16. Cogeneration technology alternatives study. Volume 1: Summary report

    Science.gov (United States)

    1980-01-01

    Data and information in the area of advanced energy conversion systems for industrial congeneration applications in the 1985-2000 time period was studied. Six current and thirty-one advanced energy conversion systems were defined and combined with appropriate balance-of-plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a framework for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. Various cogeneration strategies were analyzed and both topping and bottoming (using industrial by-product heat) applications were included. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Typically fuel energy savings of 10 to 25 percent were predicted compared to traditional on-site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Overall, fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual cost savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal-derived fuels, or coal with advanced fluid bed combustion or on-site gasification systems.

  17. Cogeneration steam turbine plant for district heating of Berovo (Macedonia)

    International Nuclear Information System (INIS)

    Armenski, Slave; Dimitrov, Konstantin

    2000-01-01

    A plant for combined heat and electric power production, for central heating of the town Berovo (Macedonia) is proposed. The common reason to use a co-generation unit is the energy efficiency and a significant reduction of environmental pollution. A coal dust fraction from B rik' - Berovo coal mine is the main energy resource for cogeneration steam turbine plant. The heat consumption of town Berovo is analyzed and determined. Based on the energy consumption of a whole power plant, e. i. the plant for combined and simultaneous production of power is proposed. All necessary facilities of cogeneration plant is examined and determined. For proposed cogeneration steam turbine power plant for combined heat and electric production it is determined: heat and electric capacity of the plant, annually heat and electrical quantity production and annually coal consumption, the total investment of the plant, the price of both heat and electric energy as well as the pay back period. (Authors)

  18. A comparison of advanced heat recovery power cycles in a combined cycle for large ships

    International Nuclear Information System (INIS)

    Larsen, Ulrik; Sigthorsson, Oskar; Haglind, Fredrik

    2014-01-01

    Strong motivation exists within the marine sector to reduce fuel expenses and to comply with ever stricter emission regulations. Heat recovery can address both of these issues. The ORC (organic Rankine cycle), the Kalina cycle and the steam Rankine cycle have received the majority of the focus in the literature. In the present work we compare these cycles in a combined cycle application with a large marine two-stroke diesel engine. We present an evaluation of the efficiency and the environmental impact, safety concerns and practical aspects of each of the cycles. A previously validated numerical engine model is combined with a turbocharger model and bottoming cycle models written in Matlab. Genetic algorithm optimisation results suggest that the Kalina cycle possess no significant advantages compared to the ORC or the steam cycle. While contributing to very high efficiencies, the organic working fluids possess high global warming potentials and hazard levels. It is concluded that the ORC has the greatest potential for increasing the fuel efficiency, and the combined cycle offers very high thermal efficiency. While being less efficient, the steam cycle has the advantages of being well proven, harmless to the environment as well as being less hazardous in comparison. - Highlights: • We compare steam, ORC (organic Rankine cycle) and Kalina cycles for waste heat recovery in marine engines. • We evaluate the efficiency and important qualitative differences. • The Kalina cycle presents no apparent advantages. • The steam cycle is well known, harmless and has a high efficiency. • The ORC has the highest efficiency but also important drawbacks

  19. A comparison of advanced heat recovery power cycles in a combined cycle for large ships

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Sigthorsson, Oskar; Haglind, Fredrik

    2014-01-01

    Strong motivation exists within the marine sector to reduce fuel expenses and to comply with ever stricter emission regulations. Heat recovery can address both of these issues. The ORC (organic Rankine cycle), the Kalina cycle and the steam Rankine cycle have received the majority of the focus...... fluids possess high global warming potentials and hazard levels. It is concluded that the ORC has the greatest potential for increasing the fuel efficiency, and the combined cycle offers very high thermal efficiency. While being less efficient, the steam cycle has the advantages of being well proven...

  20. Process heat cogeneration using a high temperature reactor

    International Nuclear Information System (INIS)

    Alonso, Gustavo; Ramirez, Ramon; Valle, Edmundo del; Castillo, Rogelio

    2014-01-01

    Highlights: • HTR feasibility for process heat cogeneration is assessed. • A cogeneration coupling for HTR is proposed and process heat cost is evaluated. • A CCGT process heat cogeneration set up is also assessed. • Technical comparison between both sources of cogeneration is performed. • Economical competitiveness of the HTR for process heat cogeneration is analyzed. - Abstract: High temperature nuclear reactors offer the possibility to generate process heat that could be used in the oil industry, particularly in refineries for gasoline production. These technologies are still under development and none of them has shown how this can be possible and what will be the penalty in electricity generation to have this additional product and if the cost of this subproduct will be competitive with other alternatives. The current study assesses the likeliness of generating process heat from Pebble Bed Modular Reactor to be used for a refinery showing different plant balances and alternatives to produce and use that process heat. An actual practical example is presented to demonstrate the cogeneration viability using the fact that the PBMR is a modular small reactor where the cycle configuration to transport the heat of the reactor to the process plant plays an important role in the cycle efficiency and in the plant economics. The results of this study show that the PBMR would be most competitive when capital discount rates are low (5%), carbon prices are high (>30 US$/ton), and competing natural gas prices are at least 8 US$/mmBTU

  1. Process heat cogeneration using a high temperature reactor

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, Gustavo, E-mail: gustavoalonso3@gmail.com [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, Ocoyoacac, Edo. De Mexico 52750 (Mexico); Instituto Politécnico Nacional, Unidad Profesional Adolfo Lopez Mateos, Ed. 9, Lindavista, D.F. 07300 (Mexico); Ramirez, Ramon [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, Ocoyoacac, Edo. De Mexico 52750 (Mexico); Valle, Edmundo del [Instituto Politécnico Nacional, Unidad Profesional Adolfo Lopez Mateos, Ed. 9, Lindavista, D.F. 07300 (Mexico); Castillo, Rogelio [Instituto Nacional de Investigaciones Nucleares, Carretera Mexico-Toluca s/n, Ocoyoacac, Edo. De Mexico 52750 (Mexico)

    2014-12-15

    Highlights: • HTR feasibility for process heat cogeneration is assessed. • A cogeneration coupling for HTR is proposed and process heat cost is evaluated. • A CCGT process heat cogeneration set up is also assessed. • Technical comparison between both sources of cogeneration is performed. • Economical competitiveness of the HTR for process heat cogeneration is analyzed. - Abstract: High temperature nuclear reactors offer the possibility to generate process heat that could be used in the oil industry, particularly in refineries for gasoline production. These technologies are still under development and none of them has shown how this can be possible and what will be the penalty in electricity generation to have this additional product and if the cost of this subproduct will be competitive with other alternatives. The current study assesses the likeliness of generating process heat from Pebble Bed Modular Reactor to be used for a refinery showing different plant balances and alternatives to produce and use that process heat. An actual practical example is presented to demonstrate the cogeneration viability using the fact that the PBMR is a modular small reactor where the cycle configuration to transport the heat of the reactor to the process plant plays an important role in the cycle efficiency and in the plant economics. The results of this study show that the PBMR would be most competitive when capital discount rates are low (5%), carbon prices are high (>30 US$/ton), and competing natural gas prices are at least 8 US$/mmBTU.

  2. Hybrid Combined Cycles with Biomass and Waste Fired Bottoming Cycle - a Literature Study

    Energy Technology Data Exchange (ETDEWEB)

    Petrov, Miroslav P.

    2002-02-01

    Biomass is one of the main natural resources in Sweden. The present low-CO{sub 2} emission characteristics of the Swedish electricity production system (hydro and nuclear) can be retained only by expansion of biofuel applications for energy purposes. Domestic Swedish biomass resources are vast and renewable, but not infinite. They must be utilized as efficiently as possible, in order to make sure that they meet the conditions for sustainability in the future. Application of efficient power generation cycles at low costs is essential for meeting this challenge. This applies also to municipal solid waste incineration with energy extraction, which should be preferred to its dumping in landfills. Hybrid dual-fuel combined cycle units are a simple and affordable way to increase the electric efficiency of biofuel energy utilization, without big investments, uncertainties or loss of reliability arising from complicated technologies. Configurations of such power cycles are very flexible and reliable. Their potential for high electric efficiency in condensing mode, high total efficiency in combined heat and power mode and unrivalled load flexibility is explored in this project. The present report is a literature study that concentrates on certain biomass utilization technologies, in particular the design and performance of hybrid combined cycle power units of various configurations, with gas turbines and internal combustion engines as topping cycles. An overview of published literature and general development trends on the relevant topic is presented. The study is extended to encompass a short overview of biomass utilization as an energy source (focusing on Sweden), history of combined cycles development with reference especially to combined cycles with supplementary firing and coal-fired hybrid combined cycles, repowering of old steam units into hybrid ones and combined cycles for internal combustion engines. The hybrid combined cycle concept for municipal solid waste

  3. Thermodynamic performance optimization of a combined power/cooling cycle

    International Nuclear Information System (INIS)

    Pouraghaie, M.; Atashkari, K.; Besarati, S.M.; Nariman-zadeh, N.

    2010-01-01

    A combined thermal power and cooling cycle has already been proposed in which thermal energy is used to produce work and to generate a sub-ambient temperature stream that is suitable for cooling applications. The cycle uses ammonia-water mixture as working fluid and is a combination of a Rankine cycle and absorption cycle. The very high ammonia vapor concentration, exiting turbine under certain operating conditions, can provide power output as well as refrigeration. In this paper, the goal is to employ multi-objective algorithms for Pareto approach optimization of thermodynamic performance of the cycle. It has been carried out by varying the selected design variables, namely, turbine inlet pressure (P h ), superheater temperature (T superheat ) and condenser temperature (T condensor ). The important conflicting thermodynamic objective functions that have been considered in this study are turbine work (w T ), cooling capacity (q cool ) and thermal efficiency (η th ) of the cycle. It is shown that some interesting and important relationships among optimal objective functions and decision variables involved in the combined cycle can be discovered consequently. Such important relationships as useful optimal design principles would have not been obtained without the use of a multi-objective optimization approach.

  4. Exergy analysis of a combined power and cooling cycle

    International Nuclear Information System (INIS)

    Fontalvo, Armando; Pinzon, Horacio; Duarte, Jorge; Bula, Antonio; Quiroga, Arturo Gonzalez; Padilla, Ricardo Vasquez

    2013-01-01

    This paper presents a comprehensive exergy analysis of a combined power and cooling cycle which combines a Rankine and absorption refrigeration cycle by using ammonia–water mixture as working fluid. A thermodynamic model was developed in Matlab ® to find out the effect of pressure ratio, ammonia mass fraction at the absorber and turbine efficiency on the total exergy destruction of the cycle. The contribution of each cycle component on the total exergy destruction was also determined. The results showed that total exergy destruction decreases when pressure ratio increases, and reaches a maximum at x ≈ 0.5, when ammonia mass fraction is varied at absorber. Also, it was found that the absorber, the boiler and the turbine had the major contribution to the total exergy destruction of the cycle, and the increase of the turbine efficiency reduces the total exergy destruction. The effect of rectification cooling source (external and internal) on the cycle output was investigated, and the results showed that internal rectification cooling reduces the total exergy destruction of the cycle. Finally, the effect of the presence or absence of the superheater after the rectification process was determined and it was obtained that the superheated condition reduces the exergy destruction of the cycle at high turbine efficiency values. Highlights: • A parametric exergy analysis of a combined power and cooling cycle is performed. • Two scenarios for rectifier cooling (internal and external) were studied. • Internal cooling source is more exergetic efficient than external cooling source. • The absorber and boiler have the largest total exergy destruction. • Our results show that the superheater reduces the exergy destruction of the cycle

  5. INCOGEN pre-feasibility study. Nuclear cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Van Heek, A.I.; De Haas, J.B.M.; Hogenbirk, A.; Klippel, H.T.; Kuijper, J.C.; Schram, R. [Netherlands Energy Research Foundation ECN, Petten (Netherlands); Hoogenboom, J.E.; Valko, J. [Interfaculty Reactor Institute IRI, Delft (Netherlands); Kanij, J.B.W.; Eendebak, B.T.; De Groot, P.C.; De Kler, R.C.F.; Stempniewicz, M.M. [KEMA, Arnhem (Netherlands); Van Dijk, A.B.; Bredman, B.; Van Essen, D.; Holtz, E.; Op `t Veld, R.; Tjemmes, J.G. [Stork Nucon, Amsterdam (Netherlands); Crommelin, G.A.K.; Crommelin-de Jonge, M.T. [eds.] [ROMAWA, Voorschoten (Netherlands)

    1997-09-01

    The Netherlands Programme to Intensify Nuclear Competence (PINK, abbreviated in Dutch) supported the technical and economical evaluation of a direct cycle High Temperature Reactor (HTR) installation for combined heat and power generation. This helium cooled, graphite moderated HTR based on the German HTR-M, is named INCOGEN (Inherently safe Nuclear COGENeration). The INCOGEN reference is a 40 MW HTR design by the US company Longmark Power International (LPI). The energy conversion system comprises a single-shaft helium turbine-compressor (2.3-1.0 MPa) directly coupled with a 16.5 MW generator, a recuperator and low-temperature (150C to 40C) heat exchangers (23 MW). Spherical fuel elements (60 mm diameter) will be added little by little, which keeps the core only marginally critical. Void core volume can accommodate added fuel for several years until defuelling. Analyses of failure scenarios (loss of coolant accident or LOCA, loss of flow accident or LOFA, anticipated transient without scram or ATWS) show no excess of maximum acceptable fuel temperature of 1600C. Scoping analyses indicate no severe graphite fires. Transient analyses of the turbine-compressor system indicate adequate control flexibility. Optimization and endurance testing of the helium turbine-compressor is recommended.

  6. Energy and cost savings results for advanced technology systems from the Cogeneration Technology Alternatives Study /CTAS/

    Science.gov (United States)

    Sagerman, G. D.; Barna, G. J.; Burns, R. K.

    1979-01-01

    The Cogeneration Technology Alternatives Study (CTAS), a program undertaken to identify the most attractive advanced energy conversion systems for industrial cogeneration applications in the 1985-2000 time period, is described, and preliminary results are presented. Two cogeneration options are included in the analysis: a topping application, in which fuel is input to the energy conversion system which generates electricity and waste heat from the conversion system is used to provide heat to the process, and a bottoming application, in which fuel is burned to provide high temperature process heat and waste heat from the process is used as thermal input to the energy conversion system which generates energy. Steam turbines, open and closed cycle gas turbines, combined cycles, diesel engines, Stirling engines, phosphoric acid and molten carbonate fuel cells and thermionics are examined. Expected plant level energy savings, annual energy cost savings, and other results of the economic analysis are given, and the sensitivity of these results to the assumptions concerning fuel prices, price of purchased electricity and the potential effects of regional energy use characteristics is discussed.

  7. Improving bioethanol production from sugarcane: evaluation of distillation, thermal integration and cogeneration systems

    International Nuclear Information System (INIS)

    Dias, Marina O.S.; Modesto, Marcelo; Ensinas, Adriano V.; Nebra, Silvia A.; Filho, Rubens Maciel; Rossell, Carlos E.V.

    2011-01-01

    Demand for bioethanol has grown considerably over the last years. Even though Brazil has been producing ethanol from sugarcane on a large scale for decades, this industry is characterized by low energy efficiency, using a large fraction of the bagasse produced as fuel in the cogeneration system to supply the process energy requirements. The possibility of selling surplus electricity to the grid or using surplus bagasse as raw material of other processes has motivated investments on more efficient cogeneration systems and process thermal integration. In this work simulations of an autonomous distillery were carried out, along with utilities demand optimization using Pinch Analysis concepts. Different cogeneration systems were analyzed: a traditional Rankine Cycle, with steam of high temperature and pressure (80 bar, 510 o C) and back pressure and condensing steam turbines configuration, and a BIGCC (Biomass Integrated Gasification Combined Cycle), comprised by a gas turbine set operating with biomass gas produced in a gasifier that uses sugarcane bagasse as raw material. Thermoeconomic analyses determining exergy-based costs of electricity and ethanol for both cases were carried out. The main objective is to show the impact that these process improvements can produce in industrial systems, compared to the current situation.

  8. Modern fluidized bed combustion in Ostrava-Karvina cogeneration plants

    Energy Technology Data Exchange (ETDEWEB)

    Mazac, V. [Energoprojekt Praha, Ostrava (Czechoslovakia); Novacek, A. [Moravskoslezske teplamy, Ostrava (Czechoslovakia); Volny, J. [Templamy Karvina (Czechoslovakia)

    1995-12-01

    The contemporary situation of our environment claims the sensitive approach to solving effective conversion of energy. Limited supplies of noble fuels and their prices evoke the need to use new combustion technologies of accessible fuels in given region without negative ecological influences. Energoproject participates in the preparation of the two projects in Ostrava-Karvin{acute a} black coal field in Czech Republic. The most effective usage of fuel energy is the combined of electricity and heat. If this physical principle is supported by a pressurized fluidized bed combustion (PFBC) one obtains a high electricity/heat ratio integrated steam-gas cycle on the basis of solid fuel. Cogeneration plant Toebovice is the dominant source (600 MW{sub th}) of Ostrava district heating system (1100 MW{sub th}). The high utilization of the installed output and utilization of the clean, compact and efficient of the PFBC technology is the principal but not the single reason for the selection of the Toebovice power plant as the first cogeneration plant for installation of the PFBC in Czech Republic. The boiler will burn black coal from the neighboring coal basin.

  9. Exergy analysis for combined regenerative Brayton and inverse Brayton cycles

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zelong; Chen, Lingen; Sun, Fengrui [College of Naval Architecture and Power, Naval University of Engineering, Wuhan 430033 (China)

    2012-07-01

    This paper presents the study of exergy analysis of combined regenerative Brayton and inverse Brayton cycles. The analytical formulae of exergy loss and exergy efficiency are derived. The largest exergy loss location is determined. By taking the maximum exergy efficiency as the objective, the choice of bottom cycle pressure ratio is optimized by detailed numerical examples, and the corresponding optimal exergy efficiency is obtained. The influences of various parameters on the exergy efficiency and other performances are analyzed by numerical calculations.

  10. Exergy analysis for combined regenerative Brayton and inverse Brayton cycles

    OpenAIRE

    Zelong Zhang, Lingen Chen, Fengrui Sun

    2012-01-01

    This paper presents the study of exergy analysis of combined regenerative Brayton and inverse Brayton cycles. The analytical formulae of exergy loss and exergy efficiency are derived. The largest exergy loss location is determined. By taking the maximum exergy efficiency as the objective, the choice of bottom cycle pressure ratio is optimized by detailed numerical examples, and the corresponding optimal exergy efficiency is obtained. The influences of various parameters on the exergy efficien...

  11. Combined cycle power plant with integrated low temperature heat (LOTHECO)

    International Nuclear Information System (INIS)

    Kakaras, E.; Doukelis, A.; Leithner, R.; Aronis, N.

    2004-01-01

    The major driver to enhance the efficiency of the simple gas turbine cycle has been the increase in process conditions through advancements in materials and cooling methods. Thermodynamic cycle developments or cycle integration are among the possible ways to further enhance performance. The current paper presents the possibilities and advantages from the LOTHECO natural gas-fired combined cycle concept. In the LOTHECO cycle, low-temperature waste heat or solar heat is used for the evaporation of injected water droplets in the compressed air entering the gas turbine's combustion chamber. Following a description of this innovative cycle, its advantages are demonstrated by comparison between different gas turbine power generation systems for small and large-scale applications, including thermodynamic and economic analysis. A commercial gas turbine (ALSTOM GT10C) has been selected and computed with the heat mass balance program ENBIPRO. The results from the energy analysis are presented and the features of each concept are discussed. In addition, the exergy analysis provides information on the irreversibilities of each process and suggested improvements. Finally, the economic analysis reveals that the combined cycle plant with a heavy-duty gas turbine is the most efficient and economic way to produce electricity at base load. However, on a smaller scale, innovative designs, such as the LOTHECO concept, are required to reach the same level of performance at feasible costs

  12. Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A

    DEFF Research Database (Denmark)

    Meroni, Andrea; La Seta, Angelo; Andreasen, Jesper Graa

    2016-01-01

    Axial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic...... Rankine cycle power systems. In this two-part paper, an overall cycle model and a model of an axial turbine were combined in order to provide a comprehensive preliminary design of the organic Rankine cycle unit, taking into account both cycle and turbine optimal designs. Part A presents the preliminary...

  13. INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

    International Nuclear Information System (INIS)

    Sandvig, Eric; Walling, Gary; Brown, Robert C.; Pletka, Ryan; Radlein, Desmond; Johnson, Warren

    2003-01-01

    Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MW e ; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system

  14. INTEGRATED PYROLYSIS COMBINED CYCLE BIOMASS POWER SYSTEM CONCEPT DEFINITION

    Energy Technology Data Exchange (ETDEWEB)

    Eric Sandvig; Gary Walling; Robert C. Brown; Ryan Pletka; Desmond Radlein; Warren Johnson

    2003-03-01

    Advanced power systems based on integrated gasification/combined cycles (IGCC) are often presented as a solution to the present shortcomings of biomass as fuel. Although IGCC has been technically demonstrated at full scale, it has not been adopted for commercial power generation. Part of the reason for this situation is the continuing low price for coal. However, another significant barrier to IGCC is the high level of integration of this technology: the gas output from the gasifier must be perfectly matched to the energy demand of the gas turbine cycle. We are developing an alternative to IGCC for biomass power: the integrated (fast) pyrolysis/ combined cycle (IPCC). In this system solid biomass is converted into liquid rather than gaseous fuel. This liquid fuel, called bio-oil, is a mixture of oxygenated organic compounds and water that serves as fuel for a gas turbine topping cycle. Waste heat from the gas turbine provides thermal energy to the steam turbine bottoming cycle. Advantages of the biomass-fueled IPCC system include: combined cycle efficiency exceeding 37 percent efficiency for a system as small as 7.6 MW{sub e}; absence of high pressure thermal reactors; decoupling of fuel processing and power generation; and opportunities for recovering value-added products from the bio-oil. This report provides a technical overview of the system including pyrolyzer design, fuel clean-up strategies, pyrolysate condenser design, opportunities for recovering pyrolysis byproducts, gas turbine cycle design, and Rankine steam cycle. The report also reviews the potential biomass fuel supply in Iowa, provide and economic analysis, and present a summery of benefits from the proposed system.

  15. Development of a proton exchange membrane fuel cell cogeneration system

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Jenn Jiang; Zou, Meng Lin [Department of Greenergy, National University of Tainan, Tainan 700 (China)

    2010-05-01

    A proton exchange membrane fuel cell (PEMFC) cogeneration system that provides high-quality electricity and hot water has been developed. A specially designed thermal management system together with a microcontroller embedded with appropriate control algorithm is integrated into a PEM fuel cell system. The thermal management system does not only control the fuel cell operation temperature but also recover the heat dissipated by FC stack. The dynamic behaviors of thermal and electrical characteristics are presented to verify the stability of the fuel cell cogeneration system. In addition, the reliability of the fuel cell cogeneration system is proved by one-day demonstration that deals with the daily power demand in a typical family. Finally, the effects of external loads on the efficiencies of the fuel cell cogeneration system are examined. Results reveal that the maximum system efficiency was as high as 81% when combining heat and power. (author)

  16. Technical And Economical FACTIBILITY To Apply A Combined Cycle

    International Nuclear Information System (INIS)

    Hernández Rangel, Elybe

    2017-01-01

    In the state of Falcon specifically in the peninsula of Paraguaná, there are two electric plants; GENEVAPCA and CADAFE. These companies are in charge of providing electrical power to the population, which is being affected by the increment of the population, plus the touristic development of the tax free zone. This reasons cause the systematic ration of the electrical power that as a consequence causes electrical interruptions for a long period of time. Due to this electrical plants can not cover the demand in its totality, there must be created alternative for usage of the electricity which would increment its production. The following thesis has an objective to analyze the technical and economical factibility to apply a combined cycle, with the purpose of increasing the electrical power supply and obtain a better thermodynamically performance. Such project was elaborated in four phases. The first phase contemplated the data collection related to the subject, obtaining important information to select the best option of the combined cycle. In the Second phase was executed the termination of the thermodynamically and energetically properties of the combined cycle, comparing the efficient of the simple cycle with the cycle mention before. As final phase, the project’s economical rentability was estimated for possible installation. (author)

  17. A combined gas cooled nuclear reactor and fuel cell cycle

    Science.gov (United States)

    Palmer, David J.

    Rising oil costs, global warming, national security concerns, economic concerns and escalating energy demands are forcing the engineering communities to explore methods to address these concerns. It is the intention of this thesis to offer a proposal for a novel design of a combined cycle, an advanced nuclear helium reactor/solid oxide fuel cell (SOFC) plant that will help to mitigate some of the above concerns. Moreover, the adoption of this proposal may help to reinvigorate the Nuclear Power industry while providing a practical method to foster the development of a hydrogen economy. Specifically, this thesis concentrates on the importance of the U.S. Nuclear Navy adopting this novel design for its nuclear electric vessels of the future with discussion on efficiency and thermodynamic performance characteristics related to the combined cycle. Thus, the goals and objectives are to develop an innovative combined cycle that provides a solution to the stated concerns and show that it provides superior performance. In order to show performance, it is necessary to develop a rigorous thermodynamic model and computer program to analyze the SOFC in relation with the overall cycle. A large increase in efficiency over the conventional pressurized water reactor cycle is realized. Both sides of the cycle achieve higher efficiencies at partial loads which is extremely important as most naval vessels operate at partial loads as well as the fact that traditional gas turbines operating alone have poor performance at reduced speeds. Furthermore, each side of the cycle provides important benefits to the other side. The high temperature exhaust from the overall exothermic reaction of the fuel cell provides heat for the reheater allowing for an overall increase in power on the nuclear side of the cycle. Likewise, the high temperature helium exiting the nuclear reactor provides a controllable method to stabilize the fuel cell at an optimal temperature band even during transients helping

  18. Status report on compact gasifier cogeneration units in Germany. Applications of the cogeneration gasifier technology; Stand kleintechnischer Vergaser-BHKW-Anlagen in Deutschland. Einsatz der BHKW-Vergasertechnologie

    Energy Technology Data Exchange (ETDEWEB)

    Zschunke, Tobias; Schuessler, Ingmar; Salomo, Bert [Hochschule Zittau/Goerlitz (Germany); Braekow, Dieter [Foerdergesellschaft Erneuerbare Energien e.V., Berlin (Germany); Treppe, Konrad [Technische Univ. Dresden (Germany). Inst. fuer Verfahrenstechnik und Umwelttechnik

    2010-07-01

    In contrast to biogas, the use of solid biomass with low water content in cogeneration units is lagging several years of development behind. A promising variant is a wood gas engine cogeneration unit. Different energy sources can be combined, e.g. in an Otto engine and a Stirling engine. The authors describe the technology for compact systems. (orig.)

  19. Cogeneration technologies, optimisation and implementation

    CERN Document Server

    Frangopoulos, Christos A

    2017-01-01

    Cogeneration refers to the use of a power station to deliver two or more useful forms of energy, for example, to generate electricity and heat at the same time. This book provides an integrated treatment of cogeneration, including a tour of the available technologies and their features, and how these systems can be analysed and optimised.

  20. Controlling systems of cogeneration blocks

    International Nuclear Information System (INIS)

    Suriansky, J.; Suriansky, J. Ml.; Puskajler, J.

    2007-01-01

    In this article the main parts of cogeneration unit control system are described. Article is aimed on electric power measurement with electricity protection as with temperature system regulation. In conclusion of the article, the control algorithm with perspective of cogeneration solve is indicated. (authors)

  1. The alarming future for cogeneration

    International Nuclear Information System (INIS)

    Koevoet, H.

    2000-01-01

    Low prices and uncertainty in pricing of energy, higher costs for investment and expensive fuels are the most important reasons why the growth of cogeneration capacity in the Netherlands stagnates. The liberalization of the energy market appears to be the malefactor. A brief overview is given of the ECN (Netherlands Energy Research Foundation) report 'Toekomst warmtekrachtkoppeling' (Future of cogeneration)

  2. Are combined cycle plants being driven to zero discharge?

    International Nuclear Information System (INIS)

    Sinha, P.K.; Narula, R.G.; Weidinger, G.F.

    1991-01-01

    This paper discusses the water-related environmental issues of siting combined cycle plants, including availability of plant makeup water and wastewater discharge. The need for water treatment equipment for waste minimization, recycle, and/or zero discharge is discussed. The key water-related permit issues and preliminary design commitments are demonstrated via case histories

  3. Parametric Investigation and Thermoeconomic Optimization of a Combined Cycle for Recovering the Waste Heat from Nuclear Closed Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Lihuang Luo

    2016-01-01

    Full Text Available A combined cycle that combines AWM cycle with a nuclear closed Brayton cycle is proposed to recover the waste heat rejected from the precooler of a nuclear closed Brayton cycle in this paper. The detailed thermodynamic and economic analyses are carried out for the combined cycle. The effects of several important parameters, such as the absorber pressure, the turbine inlet pressure, the turbine inlet temperature, the ammonia mass fraction, and the ambient temperature, are investigated. The combined cycle performance is also optimized based on a multiobjective function. Compared with the closed Brayton cycle, the optimized power output and overall efficiency of the combined cycle are higher by 2.41% and 2.43%, respectively. The optimized LEC of the combined cycle is 0.73% lower than that of the closed Brayton cycle.

  4. Thermodynamic assessment of a wind turbine based combined cycle

    International Nuclear Information System (INIS)

    Rabbani, M.; Dincer, I.; Naterer, G.F.

    2012-01-01

    Combined cycles use the exhaust gases released from a Gas Turbine (GT). Approximately 30–40% of the turbine shaft work is typically used to drive the Compressor. The present study analyzes a system that couples a Wind Turbine (WT) with a combined cycle. It demonstrates how a WT can be used to supply power to the Compressor in the GT cycle and pump fluid through a reheat Rankine cycle, in order to increase the overall power output. Three different configurations are discussed, namely high penetration, low penetration and wind power addition. In the case of a low electricity demand and high penetration configuration, extra wind power is used to compress air which can then be used in the low penetration configuration. During a high load demand, all the wind power is used to drive the pump and compressor and if required additional compressed air is supplied by a storage unit. The analysis shows that increasing the combustion temperature reduces the critical velocity and mass flow rate. Increases in wind speed reduce both energy and exergy efficiency of the overall system. -- Highlights: ► This study analyzes a system that couples a wind turbine with a combined power generation cycle. ► Surplus wind power is used to compress air, which is then stored and used at a later time. ► Increasing the pressure ratio will reduce the work ratio between the Rankine and Brayton cycles. ► A higher combustion temperature will increase the net work output, as well as the system energy and exergy efficiencies.

  5. Optimization of the triple-pressure combined cycle power plant

    Directory of Open Access Journals (Sweden)

    Alus Muammer

    2012-01-01

    Full Text Available The aim of this work was to develop a new system for optimization of parameters for combined cycle power plants (CCGTs with triple-pressure heat recovery steam generator (HRSG. Thermodynamic and thermoeconomic optimizations were carried out. The objective of the thermodynamic optimization is to enhance the efficiency of the CCGTs and to maximize the power production in the steam cycle (steam turbine gross power. Improvement of the efficiency of the CCGT plants is achieved through optimization of the operating parameters: temperature difference between the gas and steam (pinch point P.P. and the steam pressure in the HRSG. The objective of the thermoeconomic optimization is to minimize the production costs per unit of the generated electricity. Defining the optimal P.P. was the first step in the optimization procedure. Then, through the developed optimization process, other optimal operating parameters (steam pressure and condenser pressure were identified. The developed system was demonstrated for the case of a 282 MW CCGT power plant with a typical design for commercial combined cycle power plants. The optimized combined cycle was compared with the regular CCGT plant.

  6. Sustainability assessment of cogeneration sector development in Croatia

    International Nuclear Information System (INIS)

    Liposcak, Marko; Afgan, Naim H.; Duic, Neven; Graca Carvalho, Maria da

    2006-01-01

    The effective and rational energy generation and supply is one of the main presumptions of sustainable development. Combined heat and power production, or co-generation, has clear environmental advantages by increasing energy efficiency and decreasing carbon emissions. However, higher investment cost and more complicated design and maintenance sometimes-present disadvantages from the economical viability point of view. As in the case of most of economies in transition in Central and Eastern Europe, Croatia has a strong but not very efficient co-generation sector, delivering 12% of the final energy consumption. District heating systems in the country's capital Zagreb and in city of Osijek represent the large share of the overall co-generation capacity. Besides district heating, co-generation in industry sector is also relatively well developed. The paper presents an attempt to assess the sustainability of Croatian co-generation sector future development. The sustainability assessment requires multi-criteria assessment of specific scenarios to be taken into consideration. In this respect three scenarios of Croatian co-generation sector future development are taken into consideration and for each of them environmental, social and economic sustainability indicators are defined and calculated. The assessment of complex relationships between environmental, social and economic aspects of the system is based on the multi-criteria decision-making procedure. The sustainability assessment is based on the General Sustainability Index rating for different cases reflecting different criteria and their priority. The method of sustainability assessment is applied to the Croatian co-generation sector contributing to the evaluation of different strategies and definition of a foundation for policy related to the sustainable future cogeneration sector development

  7. Cogeneration and taxation in a liberalised Nordic power market

    International Nuclear Information System (INIS)

    Jess Olsen, O.; Munksgaard, J.

    1997-01-01

    This report is about the impact of the liberalisation of the Nordic power market on cogeneration of heat and power. Special attention is given to the effects on competition of the entirely different tax regimes in the Nordic countries. Some of the main questions answered in this study are: Which cogeneration technologies are able to compete on a liberalised power market? What are the consequences of different tax structures in the four countries for cross-border competition? Which principles should be applied if a common Nordic tax structure is to be developed? The following countries are included in the study: Denmark, Finland, Norway and Sweden. Today, cogeneration provides a larger contribution to the energy supply in the Nordic countries than elsewhere in the world. Our analysis demonstrates that most cogeneration technologies can compete with the power-only technologies. This is the case with respect to both long- and short-term marginal costs. The main exception is the very expensive straw-fired cogeneration technology. The analysis is extended to include the effects of the existing tax regimes (in 1996) in Denmark, Finland and Sweden as well as of the combines energy/CO 2 -tax that was proposed in 1992 by the European Commission. Each of the four tax regimes preserve the competitiveness of cogeneration within its own regime, i.e. if a given cogeneration technology is competitive without taxes it will remain so in a closed market when either Danish, Finnish, Swedish or European taxes are added. The implication of this is that the same cogeneration technology will be exposed to very different conditions in an open power market with cross-border competition, if the present tax regimes in the Nordic countries are allowed to continue. (EG) Also published in Danish. 15 refs

  8. Cogeneration and taxation in a liberalised Nordic power market

    Energy Technology Data Exchange (ETDEWEB)

    Jess Olsen, O.; Munksgaard, J.

    1997-12-31

    This report is about the impact of the liberalisation of the Nordic power market on cogeneration of heat and power. Special attention is given to the effects on competition of the entirely different tax regimes in the Nordic countries. Some of the main questions answered in this study are: Which cogeneration technologies are able to compete on a liberalised power market? What are the consequences of different tax structures in the four countries for cross-border competition? Which principles should be applied if a common Nordic tax structure is to be developed? The following countries are included in the study: Denmark, Finland, Norway and Sweden. Today, cogeneration provides a larger contribution to the energy supply in the Nordic countries than elsewhere in the world. Our analysis demonstrates that most cogeneration technologies can compete with the power-only technologies. This is the case with respect to both long- and short-term marginal costs. The main exception is the very expensive straw-fired cogeneration technology. The analysis is extended to include the effects of the existing tax regimes (in 1996) in Denmark, Finland and Sweden as well as of the combines energy/CO{sub 2}-tax that was proposed in 1992 by the European Commission. Each of the four tax regimes preserve the competitiveness of cogeneration within its own regime, i.e. if a given cogeneration technology is competitive without taxes it will remain so in a closed market when either Danish, Finnish, Swedish or European taxes are added. The implication of this is that the same cogeneration technology will be exposed to very different conditions in an open power market with cross-border competition, if the present tax regimes in the Nordic countries are allowed to continue. (EG) Also published in Danish. 15 refs.

  9. Development of cogeneration in Spain and financing methods

    International Nuclear Information System (INIS)

    Garcia, G.R.

    1994-01-01

    From 1980 there is in force in Spain a proper legal framework that could be considered a sound support to further cogeneration development. Despite this cogeneration law, a very few schemes were built. In 1986 IDAE, a state company attached to the Spanish Ministry of Industry and Energy, began a Cogeneration Programme focussed to a higher cogeneration utilisation. This programme has three main foundations: Technology dissemination; Technical support; Investment financing. As a result of these activities more than 1000 MW additional power schemes have been ordered all over the country and, as a consequence, cogenerated electricity will be multiplied by three in respect with the previous situation. A 20% of this new capacity has been developed directly by IDAE, that has invested approximately 90 million US Dollar through third party financing technics. The National Energy Plan 1991-2000 established the energy policy actuations in Spain for the present decade, giving importance to cogeneration development. This paper explains the way this development has been achieved, outlining IDAE's engagement to finance combined heat and power schemes through its comprehensive way of performing third party financing systems. (au)

  10. Analysis of power and cooling cogeneration using ammonia-water mixture

    International Nuclear Information System (INIS)

    Padilla, Ricardo Vasquez; Demirkaya, Goekmen; Goswami, D. Yogi; Stefanakos, Elias; Rahman, Muhammad M.

    2010-01-01

    Development of innovative thermodynamic cycles is important for the efficient utilization of low-temperature heat sources such as solar, geothermal and waste heat sources. This paper presents a parametric analysis of a combined power/cooling cycle, which combines the Rankine and absorption refrigeration cycles, uses ammonia-water mixture as the working fluid and produces power and cooling simultaneously. This cycle, also known as the Goswami Cycle, can be used as a bottoming cycle using waste heat from a conventional power cycle or as an independent cycle using solar or geothermal energy. A thermodynamic study of power and cooling cogeneration is presented. The performance of the cycle for a range of boiler pressures, ammonia concentrations and isentropic turbine efficiencies are studied to find out the sensitivities of net work, amount of cooling and effective efficiencies. The roles of rectifier and superheater on the cycle performance are investigated. The cycle heat source temperature is varied between 90-170 o C and the maximum effective first law and exergy efficiencies for an absorber temperature of 30 o C are calculated as 20% and 72%, respectively. The turbine exit quality of the cycle for different boiler exit scenarios shows that turbine exit quality decreases when the absorber temperature decreases.

  11. Studying effect of heating plant parameters on performances of a geothermal-fuelled series cogeneration plant based on Organic Rankine Cycle

    International Nuclear Information System (INIS)

    Habka, Muhsen; Ajib, Salman

    2014-01-01

    Highlights: • We analyzed performances of a series ORC–CHP plant versus the heating plant parameters. • ORC–CHP power is destructed when raising the heat demand or the return temperature. • Only the high supply temperatures of the heating plant affect negatively the performances. • Reducing the return temperature optimizes both the energetic and exergetic criteria. • Increasing the heat demand improves the exergetic efficiency of the total CHP system. - Abstract: The present work aims to analyze the performance characteristics of the series Combined Heat and Power (CHP) system based on Organic Rankine Cycle (ORC) under influence of the heating plant parameters without considering the chemistry of the geothermal water considered as heat source. For evaluation, energetic and exergetic criteria along with the heat transfer capacities have been determined, and also the working fluid R134a has been used. The results showed that increasing the heat demand or the return temperature and only the high supply temperatures lead to destruct the net power generated by the ORC–CHP system. While, influence of the last parameters on the total exergy efficiency and losses is different; whereas raising the heat demands optimizes these exergetic indicators, variation of the supply temperature leads to an optimum for these performances. Since increasing the return temperature has purely negative impacts on all exergetic and energetic criteria, the latter can be improved by reducing this temperature with attention to the heat transfer capacities. Thus, reduction of the return temperature about 5 °C lowers the exhausted stream losses by app. 25% and enhances the power generation by app. 52% and the total exergy efficiency by 9%

  12. Combination of IVF and IVM in naturally cycling women

    DEFF Research Database (Denmark)

    Tang-Pedersen, Mikael; Westergaard, Lars Grabow; Erb, Karin

    2012-01-01

    This study investigated the combination of an unstimulated IVF cycle with in-vitro maturation (IVM) of additional immature cumulus-oocyte-complexes (COC) from the same cycle collected at the same time as the spontaneous preovulatory follicle. This could potentially improve rates of embryo transfer...... and pregnancy/live births compared with conventional unstimulated IVF treatment and at the same time eliminate the risk of ovarian hyperstimulation syndrome. This prospective trial included 77 women with regular menstrual cycles. Age at inclusion was between 20 and 37 years. Results showed a retrieval rate...... between endometrial factors and IVM oocytes together with unknown competence of IVM embryos is suspected. For some time, there has been an increasing interest in mild approaches for fertility treatment, in particular IVF. In-vitro maturation (IVM) of immature eggs outside the ovaries followed by IVF...

  13. Environmental flows and life cycle assessment of associated petroleum gas utilization via combined heat and power plants and heat boilers at oil fields

    International Nuclear Information System (INIS)

    Rajović, Vuk; Kiss, Ferenc; Maravić, Nikola; Bera, Oskar

    2016-01-01

    Highlights: • Environmental impact of associated petroleum gas flaring is discussed. • A modern trend of introducing cogeneration systems to the oil fields is presented. • Three alternative utilization options evaluated with life cycle assessment method. • Producing electricity and/or heat instead of flaring would reduce impacts. - Abstract: Flaring of associated petroleum gas is a major resource waste and causes considerable emissions of greenhouse gases and air pollutants. New environmental regulations are forcing oil industry to implement innovative and sustainable technologies in order to compete in growing energy market. A modern trend of introducing energy-effective cogeneration systems to the oil fields by replacing flaring and existing heat generation technologies powered by associated petroleum gas is discussed through material flow analysis and environmental impact assessment. The environmental assessment is based on the consequential life cycle assessment method and mainly primary data compiled directly from measurements on Serbian oil-fields or company-supplied information. The obtained results confirm that the utilization of associated petroleum gas via combined heat and power plants and heat boilers can provide a significant reduction in greenhouse gas emissions and resource depletion by displacing marginal production of heat and electricity. At the base case scenario, which assumes a 100% heat realization rate, the global warming potential of the combined heat and power plant and heat boiler scenarios were estimated at −4.94 and −0.54 kg CO_2_e_q Sm"−"3, whereas the cumulative fossil energy requirements of these scenarios were −48.7 and −2.1 MJ Sm"−"3, respectively. This is a significant reduction compared to the global warming potential (2.25 kg CO_2_e_q Sm"−"3) and cumulative fossil energy requirements (35.36 MJ Sm"−"3) of flaring. Nevertheless, sensitivity analyses have shown that life cycle assessment results are sensitive

  14. The market outlook for integrated gasification combined cycle technology

    International Nuclear Information System (INIS)

    MacGregor, P.R.; Maslak, C.E.; Stoll, H.G.

    1991-01-01

    Integrated gasification combined cycle (IGCC) technology was developed in the 1970s and is now competitive with other coal fired technologies. Because it is a new technology, IGCC technology developments are continuing at a rapid pace and the trend in decreasing capital costs is similar to the same trend seen during the early decades of simple cycle gas turbines. Consequently, IGCC technology is expected to be even more economical during the mid and late 1990s than it is today. The objective of this paper is to provide an examination of the basic economic principles of IGCC technology and to illustrate the extent to which this technology is a viable least-cost generation addition technology. Moreover, key reliability and emissions issues are addressed in relation to the technology alternatives. This paper is organized to first review the IGCC technology and to contrast its reliability, emission, performance and cost data with the three key commercially proven technologies: simple cycle combustion turbines, combined cycle plants, and coal-fired steam plants. Economic screening curves are used to illustrate the need for a balanced generation expansion mix of technologies. The regional market opportunity for coal fueled technology orders in the US from 1992 through 2005 is presented

  15. Research Technology (ASTP) Rocket Based Combined Cycle (RBCC) Engine

    Science.gov (United States)

    2004-01-01

    Pictured is an artist's concept of the Rocket Based Combined Cycle (RBCC) launch. The RBCC's overall objective is to provide a technology test bed to investigate critical technologies associated with opperational usage of these engines. The program will focus on near term technologies that can be leveraged to ultimately serve as the near term basis for Two Stage to Orbit (TSTO) air breathing propulsions systems and ultimately a Single Stage To Orbit (SSTO) air breathing propulsion system.

  16. Predominantly elastic crack growth under combined creep-fatigue cycling

    International Nuclear Information System (INIS)

    Lloyd, G.J.

    1979-01-01

    A rationalization of the various observed effects of combined creep-fatigue cycling upon predominantly elastic fatigue-crack propagation in austenitic steel is presented. Existing and new evidence is used to show two main groups of behaviour: (i) material and cycling conditions which lead to modest increases (6-8 times) in the rate of crack growth are associated with relaxation-induced changes in the material deformation characteristics, and (ii) material and cycling conditions severe enough to generate internal fracture damage lead to significant (up to a factor of 30) increases in crack growth rate when compared with fast-cycling crack propagation rates at the same temperature. A working hypothesis is presented to show that the boundary between the two groups occurs when the scale of the nucleated creep damage is of the same magnitude as the crack tip opening displacement. This leads to the possibility of unstable crack advance. Creep crack growth rates are shown to provide an upper bound to creep-fatigue crack growth rates when crack advance is unstable. If the deformation properties only are affected by the creep-fatigue cycling then creep crack growth rates provide a lower bound. The role of intergranular oxygen corrosion in very low frequency crack growth tests is also briefly discussed. (author)

  17. Exergy optimization for a novel combination of organic Rankine cycles, Stirling cycle and direct expander turbines

    Science.gov (United States)

    Moghimi, Mahdi; Khosravian, Mohammadreza

    2018-06-01

    In this paper, a novel combination of organic Rankine cycles (ORCs), Stirling cycle and direct expander turbines is modeled and optimized using the genetic algorithm. The Exergy efficiency is considered as an objective function in the genetic algorithm. High efficiency is the main advantage of Stirling cycle, however, it needs nearly isothermal compressor and turbine. Therefore, an argon ORC and a R14 ORC are placed before and after the Striling cycle along with two expander turbines at the end of the line. Each component and cycle of the proposed plant in this article is verified by the previous works available in the literature and good agreement is achieved. The obtained results reveal that 27.98%, 20.86% and 12.90% of the total cold exergy are used by argon ORC, Stirling cycle and R14 ORC, respectively. Therefore, utilization of the Stirling cycle is a good idea for the LNG line cold exergy. The maximum exergy destruction occurs in the heat exchanger after the argon ORC (85.786 kJ/s per one kg/s LNG) due to the wasted cold exergy, which can be used for air conditioning systems in the plant. Finally, it would be shown that the maximum efficiency of the proposed plant is 54.25% and the maximum output power is 355.72 kW.

  18. Exergy optimization for a novel combination of organic Rankine cycles, Stirling cycle and direct expander turbines

    Science.gov (United States)

    Moghimi, Mahdi; Khosravian, Mohammadreza

    2018-01-01

    In this paper, a novel combination of organic Rankine cycles (ORCs), Stirling cycle and direct expander turbines is modeled and optimized using the genetic algorithm. The Exergy efficiency is considered as an objective function in the genetic algorithm. High efficiency is the main advantage of Stirling cycle, however, it needs nearly isothermal compressor and turbine. Therefore, an argon ORC and a R14 ORC are placed before and after the Striling cycle along with two expander turbines at the end of the line. Each component and cycle of the proposed plant in this article is verified by the previous works available in the literature and good agreement is achieved. The obtained results reveal that 27.98%, 20.86% and 12.90% of the total cold exergy are used by argon ORC, Stirling cycle and R14 ORC, respectively. Therefore, utilization of the Stirling cycle is a good idea for the LNG line cold exergy. The maximum exergy destruction occurs in the heat exchanger after the argon ORC (85.786 kJ/s per one kg/s LNG) due to the wasted cold exergy, which can be used for air conditioning systems in the plant. Finally, it would be shown that the maximum efficiency of the proposed plant is 54.25% and the maximum output power is 355.72 kW.

  19. An HTR cogeneration system for industrial application

    International Nuclear Information System (INIS)

    Haverkate, B.R.W.; Van Heek, A.I.; Kikstra, J.F.

    1999-01-01

    Because of its favourable characteristics of safety and simplicity the high-temperature reactor (HTR) could become a competitive heat source for a cogeneration unit. The Netherlands is a world leading country in the field of cogeneration. As nuclear energy remains an option for the medium and long term in this country, systems for nuclear cogeneration should be explored and developed. Hence, ECN Nuclear Research is developing a conceptual design of an HTR for Combined generation of Heat and Power (CHP) for the industry in and outside the Netherlands. The design of this small CHP-unit for industrial applications is mainly based on a pre-feasibility study in 1996, performed by a joint working group of five Dutch organisations, in which technical feasibility was shown. The concept that was subject of that study, INCOGEN, used a 40 MW thermal pebble bed HTR and produced a maximum amount of electricity plus low temperature heat. The system has been improved to produce industrial quality heat, and has been renamed ACACIA. The output of this installation is 14 MW electricity and 17 tonnes of steam per hour, with a pressure of 10 bar and a temperature of 220C. The economic characteristics of this installation turned out to be much more favourable using modern cost data. 15 refs

  20. CANDU combined cycles featuring gas-turbine engines

    International Nuclear Information System (INIS)

    Vecchiarelli, J.; Choy, E.; Peryoga, Y.; Aryono, N.A.

    1998-01-01

    In the present study, a power-plant analysis is conducted to evaluate the thermodynamic merit of various CANDU combined cycles in which continuously operating gas-turbine engines are employed as a source of class IV power restoration. It is proposed to utilize gas turbines in future CANDU power plants, for sites (such as Indonesia) where natural gas or other combustible fuels are abundant. The primary objective is to eliminate the standby diesel-generators (which serve as a backup supply of class III power) since they are nonproductive and expensive. In the proposed concept, the gas turbines would: (1) normally operate on a continuous basis and (2) serve as a reliable backup supply of class IV power (the Gentilly-2 nuclear power plant uses standby gas turbines for this purpose). The backup class IV power enables the plant to operate in poison-prevent mode until normal class IV power is restored. This feature is particularly beneficial to countries with relatively small and less stable grids. Thermodynamically, the advantage of the proposed concept is twofold. Firstly, the operation of the gas-turbine engines would directly increase the net (electrical) power output and the overall thermal efficiency of a CANDU power plant. Secondly, the hot exhaust gases from the gas turbines could be employed to heat water in the CANDU Balance Of Plant (BOP) and therefore improve the thermodynamic performance of the BOP. This may be accomplished via several different combined-cycle configurations, with no impact on the current CANDU Nuclear Steam Supply System (NSSS) full-power operating conditions when each gas turbine is at maximum power. For instance, the hot exhaust gases may be employed for feedwater preheating and steam reheating and/or superheating; heat exchange could be accomplished in a heat recovery steam generator, as in conventional gas-turbine combined-cycle plants. The commercially available GateCycle power plant analysis program was applied to conduct a

  1. DDACE cogeneration systems : 10 case studies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    DDACE Power Systems are experts in green energy power generation and provide solutions that deal with waste and industrial by-products. The company develops practical energy solutions that address environmental and financial concerns facing both industrial and municipal customers. The following 10 case studies are examples of the installations that DDACE Power Systems have completed in recent years: (1) a combined heat and emergency power installation on the roof of a 19 storey apartment building on Bloor Street in Toronto, Ontario. The cogeneration package provides electricity and heat to the entire building, replacing an old diesel generator, (2) a combined heat and emergency power installation at the Villa Colombo extended care facility in Vaughan, Ontario. The cogeneration system provides heat and power to the building, as well as emergency power, (3) emergency standby power with demand response capabilities at Sobeys Distribution Warehouse in Vaughan, Ontario. The primary purpose of the 2.4 MW low emission, natural gas fuelled emergency standby generator is to provide emergency power to the building in the event of a grid failure, (4) a dual fuel combined heat and power installation at the Queensway Carleton Hospital in Ottawa, Ontario that provides electricity, hot water and steam to all areas of the hospital, (5) a tri-generation installation at the Ontario Police College in Aylmer, Ontario which provides power and heat to the building as well as emergency power in the event of a grid failure. An absorption chiller provides cooling in the summer and an exhaust emission control system reduces NOx emissions, (6) a biomass gasification installation at Nexterra Energy in Kamloops, British Columbia. The 239 kW generator is fueled by synthesis gas, (7) biogas utilization at Fepro Farms in Cobden, Ontario for treatment of the facility's waste products. The biogas plant uses cow manure, as well as fats, oil and grease from restaurants to produce electricity and

  2. Cogenerators stretch the capital markets

    International Nuclear Information System (INIS)

    Robinson, Danielle.

    1993-01-01

    Independent power generation projects are being planned worldwide. But to finance them, the developers are starting to look increasingly for non-bank sources of funds. Key cogeneration finance deals are discussed in this article. (Author)

  3. Cogeneration using small sized series connected units: Feasibility study

    International Nuclear Information System (INIS)

    Tondelli, F.; Bergamini, G.

    1992-01-01

    This paper evidences the technical/economic feasibility of the use of methane fuelled modular cogeneration systems based on small series connected Otto or Diesel cycle engines delivering from 20 to 90 kW of power. Ample reference is made to the successful application of modular cogeneration systems to supply low temperature thermal energy to hospitals, hotels, food processing firms, etc., in Italy. The cost benefit analysis covers many aspects: design, manufacturing, operation, performance, maintenance and safety. Suggestions are also made as to optimum contractual arrangements for equipment service and maintenance, as well as, for the exchange of power with local utilities

  4. Cogeneration in Australia. Situation and prospects

    International Nuclear Information System (INIS)

    1997-01-01

    This Research Paper is mainly concerned with the status and prospects for cogeneration in Australia. An introductory chapter reviews the fundamentals of cogeneration, covering both technical and institutional aspects. A range of technologies are employed in cogeneration: these technologies and their efficiency and environmental impact effects are discussed in Chapter 2. The economics of cogeneration are a major factor in the profitability of current and potential plants. Potential factors affecting cogeneration economics are discussed .The status of cogeneration in Australia is reviewed for each State and Territory, and includes a number of case studies of existing plants. Government (federal, state, territory) policies that have a significant impact on the attractiveness of cogeneration are reviewed. Finally, the future prospects for cogeneration in Australia, drawing on the preceding chapters and a review of estimated potentials for cogeneration in Australia are presented

  5. The development and chemistry of high efficiency combined cycle plants

    International Nuclear Information System (INIS)

    Svoboda, Robert

    1999-01-01

    This paper presents a boiler concept based on the combination of a low-pressure drum-type boiler with high-pressure once-through boiler and the appropriate water/steam cycle. An all volatile treatment is used in the low-pressure boiler and oxygenated treatment for the once-through high pressure system. Impurity control is achieved by adapted system design and materials, high quality make-up, an appropriate cleanliness concept and clean-up procedures for a cold start. Cycle refreshing is realized by blowdown from the high-pressure water-separator. This concept utilizes simper and less equipment than traditional solutions, resulting in increased power plant reliability and less requirement on maintenance and on capital cost [it

  6. Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part B

    DEFF Research Database (Denmark)

    La Seta, Angelo; Meroni, Andrea; Andreasen, Jesper Graa

    2016-01-01

    Organic Rankine cycle (ORC) power systems have recently emerged as promising solutions for waste heat recovery in low- and medium-size power plants. Their performance and economic feasibility strongly depend on the expander. The design process and efficiency estimation are particularly challenging...... due to the peculiar physical properties of the working fluid and the gas-dynamic phenomena occurring in the machine. Unlike steam Rankine and Brayton engines, organic Rankine cycle expanders combine small enthalpy drops with large expansion ratios. These features yield turbine designs with few highly...... is the preliminary design of an organic Rankine cycle turbogenerator to increase the overall energy efficiency of an offshore platform. For an increase in expander pressure ratio from 10 to 35, the results indicate up to 10% point reduction in expander performance. This corresponds to a relative reduction in net...

  7. Effects of variable loads on equipment and cogeneration cycles performance; Influencia da variacao da carga no rendimento de equipamentos e ciclos de co-geracao

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Mario A.B.; Balestieri, Jose A.P. [UNESP, Guaratingueta, SP (Brazil). Escola de Engenharia. Dept. de Engenharia Mecanica]. E-mails: basulto1@uol.com.br; basulto@feg.unesp.br; perella@feg.unesp.br

    2000-07-01

    This article presents some aspects relative to the effects of changing loads on steam.generators and turbines. When the equipment solicitation varies due to industrial process demand changes, the equipment work in off-design point, altering its efficiency and the specific fuel rate. This work do not look for a detailed and exhaustive determination of the performance variation with the load but shows that in the selection of equipment this variation can have effects over the consume and the costs. In the present article it is assumed that the load variations are known, and the effects on the equipment efficiency were took from the correlated literature. An example of a Rankine cycle and other of a Brayton cycle are discussed, altering the operational conditions estimating the operating cost for each case. (author)

  8. Integrated gasification combined cycle for acid rain control

    Energy Technology Data Exchange (ETDEWEB)

    Simbeck, D.R.; Dickenson, R.L.

    1986-10-01

    The role of integrated coal gasification combined-cycle power plants in the abatement of emission of SO/sub 2/ and NO/sub 2/ which lead to acid rain is discussed. The economics of this IGCC approach are assessed for a nominal 500 MW plant size. Phased construction of IGCC plants is recommended as a means of reducing SO/sub 2/ and NO/sub x/ emissions noting that high-sulfur coals could continue to be used. It is also noted that phased construction IGCC is the only acid rain control technology that greatly reduces NO/sub x/. 17 references.

  9. Energy efficiency - cogeneration - marketing - natural gas market: a complete cycle; Eficiencia energetica - cogeracao - marketing - mercado de gas natural: um ciclo completo

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, J. Ricardo Uchoa C. [PETROBRAS - Gas e Energia, Rio de Janeiro, RJ (Brazil). Unidade de Negocios de Gas Natural; Aragao, Raimundo [International Institute for Energy Conservation - IIEC, Rio de Janeiro, RJ (Brazil); Arruda, Rodrigo

    2004-07-01

    This paper shows the current level of some technologies which are applied in Combined Heat Power - CHP, having natural gas as fuel, and the future perspectives for its technological advances. The work introduces the economic feasibility of these technologies having as reference the present prices of electricity and natural gas in Brazilian Market. This report also informs the influence of specific parameters in Combined Heat Power - CHP projects net present value. Finally the paper shows the main barrels for Combined Heat Power - CHP dissemination in Brazil and indicates some recommendations on how to eliminate and/or attenuate them. (author)

  10. Can Dutch co-generation survive threats of the liberalisation of the energy markets

    International Nuclear Information System (INIS)

    Battjes, J.J.; Rijkers, F.A.M.

    2000-07-01

    The paper presents an analysis of the effects of liberalisation of the Dutch energy markets on the future development of combined heat and power generation (co-generation) in the Netherlands. First, it reviews the historical growth in co-generation in the Netherlands and the supportive policy measures that have contributed to this growth. Second, the liberalisation process of the Dutch electricity market and the Dutch gas market is described. Subsequently, we discuss the impacts of these new market structures on co-generation by using two scenarios for the Dutch energy markets. Our assessment of the impacts is mainly focused on the cost-effectiveness of co-generation projects. We determine the key aspects that influence the cost-effectiveness of a co-generation project and analyse some of the calculations for different small-scale and large-scale co-generation projects. Based on the results, we conclude that investments in new co-generation plants are unlikely in the short term and the existing plants can barely produce with a positive cash flow. As many parties have an interest in reducing the negative effects of a liberalised energy market on co-generation, approaches are sought to improve the cost-effectiveness of co-generation in the Netherlands. We describe several optional supportive measures for co-generation mainly resulting from the determination of the barriers for co-generation. Moreover, Dutch authorities have already responded to these barriers by preparing policy measures such as investment subsidies and exemption from the energy tax. 2 refs

  11. Impact of support schemes and barriers in Europe on the evolution of cogeneration

    International Nuclear Information System (INIS)

    Moya, José Antonio

    2013-01-01

    This paper analyses the effectiveness of different support measures to promote cogeneration in the European Union. The analysis looks into the average progress of cogeneration between two different periods. The economic effect of the support measures in each country is quantified with the help of a cost–benefit analysis carried out by the Cogeneration Observatory and Dissemination Europe (CODE) project. The scope of this study is necessarily affected by the need to limit the number of projects and support measures. However, there is no evidence of a relationship between the economic advantage offered by support measures and the deployment of cogeneration in the Member States. The study considers the effect of different barriers (reported by the Member States) on the promotion of cogeneration. The individual analyses of the barriers differ widely in quality and depth. When some barriers are reported, there is an increase of the variability of the penetration of cogeneration. This counter-intuitive fact leads us to conclude that there is a lack of consistency in the barriers reported, and a clear need for consistent reporting on barriers. The possible effect of competition between measures supporting combined heat and power and renewable energy sources is also analysed. - Highlights: • Support measures to promote cogeneration are analysed. • The growth of cogeneration in European countries is not aligned with the measures in place. • None of the reported barriers for cogeneration can be considered a clear show-stopper. • The variation in the development of cogeneration when some barriers are reported raises questions about the reporting. • Countries with a high share of cogeneration are sensitive to the continuity or discontinuity of support

  12. Thermal characteristics of combined thermoelectric generator and refrigeration cycle

    International Nuclear Information System (INIS)

    Yilbas, Bekir S.; Sahin, Ahmet Z.

    2014-01-01

    Highlights: • TEM location in between the evaporator and condenser results in low coefficient of performance. • TEM location in between condenser and its ambient improves coefficient of performance of the combined system. • High temperature ratio enhances coefficient of performance of combined system. • Certain values of parameters enhance combined system performance. - Abstract: A combined thermal system consisting of a thermoelectric generator and a refrigerator is considered and the effect of location of the thermoelectric generator, in the refrigeration cycle, on the performance characteristics of the combined system is investigated. The operating conditions and their influence on coefficient of performance of the combined system are examined through introducing the dimensionless parameters, such as λ(λ = Q HTE /Q H , where Q HTE is heat transfer to the thermoelectric generator from the condenser, Q H is the total heat transfer from the condenser to its ambient), temperature ratio (θ L = T L /T H , where T L is the evaporator temperature and T H is the condenser temperature), r C (r C = C L /C H , where C L is the thermal capacitance due to heat transfer to evaporator and C H , is the thermal capacitance due to heat rejected from the condenser), θ W (θ W = T W /T H , where T W is the ambient temperature), θ C (θ C = T C /T H , where T C is the cold space temperature). It is found that the location of the thermoelectric generator in between the condenser and the evaporator decreases coefficient of performance of the combined system. Alternatively, the location of thermoelectric device in between the condenser and its ambient enhances coefficient of performance of the combined system. The operating parameters has significant effect on the performance characteristics of the combined system; in which case temperature ratio (θ L ) within the range of 0.68–0.70, r C = 2.5, θ W = 0.85, and θ C = 0.8 improve coefficient of performance of the

  13. Practical design considerations for nuclear cogeneration installations

    International Nuclear Information System (INIS)

    Koupal, J.R.

    1987-01-01

    Dual-purpose nuclear plants, cogeneration electricity and steam, offer significant economic benefits over comparable electricity generating stations. The design of such a nuclear facility requires the resolution of unique technical challenges. This paper reports on experience gained in the detailed design of such a dual-purpose facility with the steam supplied to a chemical plant for process heating. The following topics are discussed: Siting, Radioactivity of Export Steam, Optimization for Load Combinations, Steam Supply Reliability, Steam Transportation, Water Chemistry, Cost Allocation. (author)

  14. Coal fired air turbine cogeneration

    Science.gov (United States)

    Foster-Pegg, R. W.

    Fuel options and generator configurations for installation of cogenerator equipment are reviewed, noting that the use of oil or gas may be precluded by cost or legislation within the lifetime of any cogeneration equipment yet to be installed. A coal fueled air turbine cogenerator plant is described, which uses external combustion in a limestone bed at atmospheric pressure and in which air tubes are sunk to gain heat for a gas turbine. The limestone in the 26 MW unit absorbs sulfur from the coal, and can be replaced by other sorbents depending on types of coal available and stringency of local environmental regulations. Low temperature combustion reduces NOx formation and release of alkali salts and corrosion. The air heat is exhausted through a heat recovery boiler to produce process steam, then can be refed into the combustion chamber to satisfy preheat requirements. All parts of the cogenerator are designed to withstand full combustion temperature (1500 F) in the event of air flow stoppage. Costs are compared with those of a coal fired boiler and purchased power, and it is shown that the increased capital requirements for cogenerator apparatus will yield a 2.8 year payback. Detailed flow charts, diagrams and costs schedules are included.

  15. Combined-cycle steam section parametric analysis by thermo-economic simulation

    International Nuclear Information System (INIS)

    Macor, A.; Reini, M.

    1991-01-01

    In the case of industrial cogeneration plants, thermal power production is, in general, strictly dependent on the technological requirements of the production cycle, whereas, the electrical power which is produced can be auto- consumed or ceded to the utility grid. In both cases, an economic worth is given to this energy which influences the overall economic feasibility of the plant. The purpose of this paper is to examine parametric inter-relationships between economic and thermodynamic performance optimization techniques. Comparisons are then made of the results obtained with the use of the thermo- economic analysis technique suggested in this paper with those obtained with the use of indicators in other exergo-economic analysis techniques

  16. Benefit Analysis of Emergency Standby System Promoted to Cogeneration System

    Directory of Open Access Journals (Sweden)

    Shyi-Wen Wang

    2016-07-01

    Full Text Available Benefit analysis of emergency standby system combined with absorption chiller promoted to cogeneration system is introduced. Economic evaluations of such upgraded projects play a major part in the decisions made by investors. Time-of-use rate structure, fuel cost and system constraints are taken into account in the evaluation. Therefore, the problem is formulated as a mixed-integer programming problem. Using two-stage methodology and modified mixed-integer programming technique, a novel algorithm is developed and introduced here to solve the nonlinear optimization problem. The net present value (NPV method is used to evaluate the annual benefits and years of payback for the cogeneration system. The results indicate that upgrading standby generators to cogeneration systems is profitable and should be encouraged, especially for those utilities with insufficient spinning reserves, and moreover, for those having difficulty constructing new power plants.

  17. The Optimal Operation Criteria for a Gas Turbine Cogeneration System

    Directory of Open Access Journals (Sweden)

    Atsushi Akisawa

    2009-04-01

    Full Text Available The study demonstrated the optimal operation criteria of a gas turbine cogeneration system based on the analytical solution of a linear programming model. The optimal operation criteria gave the combination of equipment to supply electricity and steam with the minimum energy cost using the energy prices and the performance of equipment. By the comparison with a detailed optimization result of an existing cogeneration plant, it was shown that the optimal operation criteria successfully provided a direction for the system operation under the condition where the electric power output of the gas turbine was less than the capacity

  18. Comparison of Engine Cycle Codes for Rocket-Based Combined Cycle Engines

    Science.gov (United States)

    Waltrup, Paul J.; Auslender, Aaron H.; Bradford, John E.; Carreiro, Louis R.; Gettinger, Christopher; Komar, D. R.; McDonald, J.; Snyder, Christopher A.

    2002-01-01

    This paper summarizes the results from a one day workshop on Rocket-Based Combined Cycle (RBCC) Engine Cycle Codes held in Monterey CA in November of 2000 at the 2000 JANNAF JPM with the authors as primary participants. The objectives of the workshop were to discuss and compare the merits of existing Rocket-Based Combined Cycle (RBCC) engine cycle codes being used by government and industry to predict RBCC engine performance and interpret experimental results. These merits included physical and chemical modeling, accuracy and user friendliness. The ultimate purpose of the workshop was to identify the best codes for analyzing RBCC engines and to document any potential shortcomings, not to demonstrate the merits or deficiencies of any particular engine design. Five cases representative of the operating regimes of typical RBCC engines were used as the basis of these comparisons. These included Mach 0 sea level static and Mach 1.0 and Mach 2.5 Air-Augmented-Rocket (AAR), Mach 4 subsonic combustion ramjet or dual-mode scramjet, and Mach 8 scramjet operating modes. Specification of a generic RBCC engine geometry and concomitant component operating efficiencies, bypass ratios, fuel/oxidizer/air equivalence ratios and flight dynamic pressures were provided. The engine included an air inlet, isolator duct, axial rocket motor/injector, axial wall fuel injectors, diverging combustor, and exit nozzle. Gaseous hydrogen was used as the fuel with the rocket portion of the system using a gaseous H2/O2 propellant system to avoid cryogenic issues. The results of the workshop, even after post-workshop adjudication of differences, were surprising. They showed that the codes predicted essentially the same performance at the Mach 0 and I conditions, but progressively diverged from a common value (for example, for fuel specific impulse, Isp) as the flight Mach number increased, with the largest differences at Mach 8. The example cases and results are compared and discussed in this paper.

  19. Cogeneration for small SAGD projects

    Energy Technology Data Exchange (ETDEWEB)

    Albion, Stuart [AMEC BDR Limited (United Kingdom)

    2011-07-01

    As many SAGD projects are being developed in remote locations, the supply of a steady source of power to them becomes an important question. Connecting these remote facilities to a grid can often be difficult and costly. This presentation, by AMEC BDR Limited, promotes the use of cogeneration in small SAGD projects. Cogeneration is the generation of two forms of energy from one fuel source. In this particular case, the energy forms would be electricity and heat. In many SAGD projects, a gas turbine system is used to generate the electricity, while a heat recovery system is utilized to generate steam. The use of cogeneration systems in SAGD projects, as opposed to using separate heat and electricity systems, has the potential to significantly reduce the amount of energy lost, the amount of emissions and power costs, in addition to ensuring that there is a reliable supply of steam and electricity.

  20. The co-generation file

    International Nuclear Information System (INIS)

    Signoret, Stephane; Petitot, Pauline; Mary, Olivier; Sredojevic, Alexandre

    2017-01-01

    Whereas co-generation has many benefits (increase of energy efficiency, decrease of greenhouse gas emissions, job creation, integration of renewable energies, local and efficient production of heat and electricity, and so on), as explained in a first article, it has not enough public support in France any longer, notably for installations of more than 1 MW. However, as shown in some examples (a power and heat plant in Aulnay-sous-Bois, a factory in Graulhet), some co-generation installations have been able to take some benefit from the situation in 2015. Besides, some technological development are addressed: new burners to comply with regulations regarding NO_x and CO emissions, new engines able to operate with various gases such as hydrogen or gas produced by biomass gasification. A last article presents a co-generation boiler installed in a medical care home near Roye in the Somme district

  1. Combined cycles for pipeline compressor drives using heat

    International Nuclear Information System (INIS)

    Malewski, W.F.; Holldorff, G.M.

    1979-01-01

    Combined cycles for pipeline-booster stations using waste heat from gas turbines exhaust can improve the overall efficiency of such stations remarkably. Several working fluids are suitable. Due to existing criteria for selecting a working medium under mentioned conditions, water, ammonia, propane and butane can be considered as practical working fluids. The investigations have shown that: (1) ammonia is advantageous at low exhaust gas and ambient temperatures, (2) water is most effective at high exhaust gas and ambient temperatures, and (3), additionally, hydrocarbons are suitable in a medium range for exhaust gas and condensing temperatures. Not only thermodynamic but also operational features have to be considered. There is not one optimum working fluid but a best one suitable according to the prevailing site conditions

  2. Combined Cycle Power Generation Employing Pressure Gain Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Holley, Adam [United Technologies Corporation, East Hartford, CT (United States). Research Center

    2017-05-15

    The Phase I program assessed the potential benefit of applying pressure gain combustion (PGC) technology to a natural gas combined cycle power plant. A conceptual design of the PGC integrated gas turbine was generated which was simulated in a detailed system modeling tool. The PGC integrated system was 1.93% more efficient, produced 3.09% more power, and reduced COE by 0.58%. Since the PGC system used had the same fuel flow rate as the baseline system, it also reduced CO2 emissions by 3.09%. The PGC system did produce more NOx than standard systems, but even with the performanceand cost penalties associated with the cleanup system it is better in every measure. This technology benefits all of DOE’s stated program goals to improve plant efficiency, reduce CO2 production, and reduce COE.

  3. Exergoeconomic analysis of small-scale biomass steam cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez Sotomonte, Cesar Adolfo; Lora, Electo Eduardo Silva [Universidade Federal de Itajuba, MG (Brazil)], e-mails: c.rodriguez32@unifei.edu.br, electo@unifei.edu.br; Venturini, Osvaldo Jose; Escobar, Jose Carlos [Universidad Federal de Itajuba, MG (Brazil)], e-mail: osvaldo@unifei.edu.br

    2010-07-01

    The principal objective of this work is to develop a calculation process, based on the second law of thermodynamics, for evaluating the thermoeconomic potential of a small steam cogeneration plant using waste from pulp processing and/or sawmills as fuel. Four different configurations are presented and assessed. The exergetic efficiency of the cycles that use condensing turbines is found to be around 11%, which has almost 3 percent higher efficiency than cycles with back pressure turbines. The thermoeconomic equations used in this paper estimated the production costs varying the fuel price. The main results show that present cost of technologies in a small-scale steam cycle cogeneration do not justify the implementation of more efficient systems for biomass prices less than 100 R$/t. (author)

  4. Aeroderivative gas turbines for cogeneration

    International Nuclear Information System (INIS)

    Horner, M.W.; Thames, J.M.

    1988-01-01

    Aircraft jet engine derivative gas turbines have gained acceptance for cogeneration applications through impressive advances in technology and especially in maintainability and reliability. The best advantages of heavy industrial turbines and of reliable commercial airline jet engines have been successfully joined to meet the requirements for industrial cogeneration service. The next generation is under development and offers improved thermal efficiencies, alternate fuel capabilities, low environmental emissions, flexibility of operation and improved competitive system economics. This paper summarizes the current aero-derivative engine features and advantages with various systems, and discusses advanced features under consideration at this time

  5. Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part A: Turbine Model

    Directory of Open Access Journals (Sweden)

    Andrea Meroni

    2016-04-01

    Full Text Available Axial-flow turbines represent a well-established technology for a wide variety of power generation systems. Compactness, flexibility, reliability and high efficiency have been key factors for the extensive use of axial turbines in conventional power plants and, in the last decades, in organic Rankine cycle power systems. In this two-part paper, an overall cycle model and a model of an axial turbine were combined in order to provide a comprehensive preliminary design of the organic Rankine cycle unit, taking into account both cycle and turbine optimal designs. Part A presents the preliminary turbine design model, the details of the validation and a sensitivity analysis on the main parameters, in order to minimize the number of decision variables in the subsequent turbine design optimization. Part B analyzes the application of the combined turbine and cycle designs on a selected case study, which was performed in order to show the advantages of the adopted methodology. Part A presents a one-dimensional turbine model and the results of the validation using two experimental test cases from literature. The first case is a subsonic turbine operated with air and investigated at the University of Hannover. The second case is a small, supersonic turbine operated with an organic fluid and investigated by Verneau. In the first case, the results of the turbine model are also compared to those obtained using computational fluid dynamics simulations. The results of the validation suggest that the model can predict values of efficiency within ± 1.3%-points, which is in agreement with the reliability of classic turbine loss models such as the Craig and Cox correlations used in the present study. Values similar to computational fluid dynamics simulations at the midspan were obtained in the first case of validation. Discrepancy below 12 % was obtained in the estimation of the flow velocities and turbine geometry. The values are considered to be within a

  6. Experiences Applying Cogeneration Policies in Europe

    International Nuclear Information System (INIS)

    Marin Nortes, M.

    1997-01-01

    This paper starts by giving overview of the development of cogeneration in the European Union. The percentage of electricity produced by cogeneration is about 10%. The difference among the countries are however very big, ranging from 40% in Denmark to 2% in France. This is because the development of cogeneration in a country depends on a number of different factors. Political and regulatory factors are of a major importance. This paper tries to show this and to examinate a number of cogeneration policies in some countries in Europe. In each case, the reasons why or why not cogeneration has been successful will be analysed. (author)

  7. Exergeoconomic analysis and optimization of a novel cogeneration system producing power and refrigeration

    International Nuclear Information System (INIS)

    Akbari Kordlar, M.; Mahmoudi, S.M.S.

    2017-01-01

    Highlights: • A novel combined cooling and power cogeneration system is proposed. • Thermodynamic and exergoeconomic analyses are performed. • Optimizations are performed considering thermodynamics and economics. • An increase in turbine inlet pressure is in favor of the system performance. • Five parameters influence the total product unit cost. - Abstract: A novel combined cooling and power cogeneration system driven by geothermal hot water is proposed. The system, which is a combination of an organic Rankine cycle and an absorption refrigeration cycle, is analyzed and optimized from the viewpoints of thermodynamics and economics. The working fluid in organic Rankine cycle is ammonia and in the refrigeration cycle is an ammonia-water solution. Parametric studies are performed to identify decision parameters prior to optimization. In optimizing the system performance three design cases i.e. designs for maximum first law efficiency (case1), maximum second law efficiency (case2) and minimum total product unit cost (case3) are considered. The results show that the total products unit cost in case3 is around 20.4% and 24.3% lower than the corresponding value in case1 and 2, respectively. The lower product unit cost in case3 is accompanied with an expense of 10.21% and 4.5% reduction in the first and second law efficiencies, compared to case1 and 2, respectively. The results also indicate that concerning the costs associated with capital and exergy destruction costs of components, the priority of components for modifications are the turbine, condenser and absorber. The last component in this order are the two pumps in the system.

  8. Dynamic simulation of combined cycle power plant cycling in the electricity market

    International Nuclear Information System (INIS)

    Benato, A.; Bracco, S.; Stoppato, A.; Mirandola, A.

    2016-01-01

    Highlights: • The flexibility of traditional power plants have become of primary importance. • Three dynamic models of the same single pressure HRSG are built. • The plant dynamic behaviour is predicted. • A lifetime calculation procedure is proposed and tested. • The drum lifetime reduction is estimated. - Abstract: The energy markets deregulation coupled with the rapid spread of unpredictable energy sources power units are stressing the necessity of improving traditional power plants flexibility. Cyclic operation guarantees high profits in the short term but, in the medium-long time, cause a lifetime reduction due to thermo-mechanical fatigue, creep and corrosion. In this context, Combined Cycle Power Plants are the most concerned in flexible operation problems. For this reason, two research groups from two Italian universities have developed a procedure to estimate the devices lifetime reduction with a particular focus on steam drums and superheaters/reheaters. To assess the lifetime reduction, it is essential to predict the thermodynamic variables trend in order to describe the plant behaviour. Therefore, the core of the procedure is the power plant dynamic model. At this purpose, in this paper, three different dynamic models of the same single pressure Combined Cycle Gas Turbine are presented. The models have been built using three different approaches and are used to simulate plant behaviour under real operating conditions. Despite these differences, the thermodynamic parameters time profiles are in good accordance as presented in the paper. At last, an evaluation of the drum lifetime reduction is performed.

  9. An HTR cogeneration system for industrial applications

    International Nuclear Information System (INIS)

    Haverkate, B.R.W.; Heek, A.I. van; Kikstra, J.F.

    2001-01-01

    Because of its favourable characteristics of safety and simplicity the high-temperature reactor (HTR) could become a competitive heat source for a cogeneration unit. The Netherlands is a world leading country in the field of cogeneration. As nuclear energy remains an option for the medium and long term in this country, systems for nuclear cogeneration should be explored and developed. Hence, ECN Nuclear Research is developing a conceptual design of an HTR for Combined generation of Heat and Power (CHP) for the industry in and outside the Netherlands. The design of this small CHP-unit for industrial applications is mainly based on a pre-feasibility study in 1996, performed by a joint working group of five Dutch organisations, in which technical feasibility was shown. The concept that was subject of this study, INCOGEN, used a 40 MW thermal pebble bed HTR and produced a maximum amount of electricity plus low temperature heat. The system has been improved to produce industrial quality heat, and has been renamed ACACIA. The output of this installation is 14 MW electricity and 17 tonnes of steam per hour, with a pressure of 10 bar and a temperature of 220 deg. C. The economic characteristics of this installation turned out to be much more favourable using modern data. The research work for this installation is embedded in a programme that has links to the major HTR projects in the world. Accordingly ECN participates in several IAEA Co-ordinated Research Programmes (CRPs). Besides this, ECN is involved in the South African PBMR-project. Finally, ECN participates in the European Concerted Action on Innovative HTR. (author)

  10. Parametric-based thermodynamic analysis of organic Rankine cycle as bottoming cycle for combined-cycle power plant

    International Nuclear Information System (INIS)

    Qureshi, S.; Memon, A.G.; Abbasi, A.F.

    2017-01-01

    In Pakistan, the thermal efficiency of the power plants is low because of a huge share of fuel energy is dumped into the atmosphere as waste heat. The ORC (Organic Rankine Cycle) has been revealed as one of the promising technologies to recover waste heat to enhance the thermal efficiency of the power plant. In current work, ORC is proposed as a second bottoming cycle for existing CCPP (Combined Cycle Power Plant). In order to assess the efficiency of the plant, a thermodynamic model is developed in the ESS (Engineering Equation Solver) software. The developed model is used for parametric analysis to assess the effects of various operating parameters on the system performance. The analysis of results shows that the integration of ORC system with existing CCPP system enhances the overall power output in the range of 150.5-154.58 MW with 0.24-5% enhancement in the efficiency depending on the operating conditions. During the parametric analysis of ORC, it is observed that inlet pressure of the turbine shows a significant effect on the performance of the system as compared to other operating parameters. (author)

  11. Feasibility of cogeneration systems in chemical industry; Viabilidade de sistemas de cogeracao em industria quimica

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Moises Henrique de Andrade; Balestieri, Jose Antonio Perrella [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia

    1998-07-01

    The increasing penetration of natural gas in the Brazilian energetic market, some industries as pulp and paper, chemical and that ones related to the food and beverage processes are some of the ones that are more interested in the cogeneration practice based on the burning of this fossil fuel. An analysis of a photographic chemical industry consumption data revealed that combined cycles and Diesel units were the most suitable for thermal following strategy, considering that the four compression chillers must be maintained, and steam or gas cycles in the case of a complete substitution for absorption chillers and the same strategy. The economic attractiveness was done according to the internal return rate and payback, revealing that the investment can be returned in short time. (author)

  12. Thermodynamic analysis of a novel integrated solar combined cycle

    International Nuclear Information System (INIS)

    Li, Yuanyuan; Yang, Yongping

    2014-01-01

    Highlights: • A novel ISCC scheme with two-stage DSG fields has been proposed and analyzed. • HRSG and steam turbine working parameters have been optimized to match the solar integration. • New scheme exhibits higher solar shares in the power output and solar-to-electricity efficiency. • Thermodynamic performances between new and reference systems have been investigated and compared. - Abstract: Integrated solar combined cycle (ISCC) systems have become more and more popular due to their high fuel and solar energy utilization efficiencies. Conventional ISCC systems with direct steam generation (DSG) have only one-stage solar input. A novel ISCC with DSG system has been proposed and analyzed in this paper. The new system consists two-stage solar input, which would significantly increase solar share in the total power output. Moreover, how and where solar energy is input into ISCC system would have impact on the solar and system overall efficiencies, which have been analyzed in the paper. It has been found that using solar heat to supply latent heat for vaporization of feedwater would be superior to that to be used for sensible heating purposes (e.g. Superheating steam). The study shows that: (1) producing both the high- and low-pressure saturated steam in the DSG trough collector could be an efficient way to improve process and system performance; (2) for a given live steam pressure, the optimum secondary and reheat steam conditions could be matched to reach the highest system thermal efficiency and net solar-to-electricity efficiency; (3) the net solar-to-electricity efficiency could reach up to 30% in the novel two-stage ISCC system, higher than that in the one-stage ISCC power plant; (4) compared with the conventional combined cycle gas turbine (CCGT) power system, lower stack temperature could be achieved, owing to the elimination of the approach-temperature-difference constraint, resulting in better thermal match in the heat recovery steam generator

  13. Gas fired combined cycle plant in Singapore: energy use, GWP and cost-a life cycle approach

    International Nuclear Information System (INIS)

    Kannan, R.; Leong, K.C.; Osman, Ramli; Ho, H.K.; Tso, C.P.

    2005-01-01

    A life cycle assessment was performed to quantify the non-renewable (fossil) energy use and global warming potential (GWP) in electricity generation from a typical gas fired combined cycle power plant in Singapore. The cost of electricity generation was estimated using a life cycle cost analysis (LCCA) tool. The life cycle assessment (LCA) of a 367.5 MW gas fired combined cycle power plant operating in Singapore revealed that hidden processes consume about 8% additional energy in addition to the fuel embedded energy, and the hidden GWP is about 18%. The natural gas consumed during the operational phase accounted for 82% of the life cycle cost of electricity generation. An empirical relation between plant efficiency and life cycle energy use and GWP in addition to a scenario for electricity cost with varying gas prices and plant efficiency have been established

  14. Optimum design and thermodynamic analysis of a gas turbine and ORC combined cycle with recuperators

    International Nuclear Information System (INIS)

    Cao, Yue; Gao, Yike; Zheng, Ya; Dai, Yiping

    2016-01-01

    Highlights: • A GT-ORC combined cycle with recuperators was designed. • The effect of the ORC turbine inlet pressure on the combined cycle was examined. • Toluene was a more suitable working fluid for the GT-ORC combined cycle. • The GT-ORC combined cycle performed better than the GT-Rankine combined cycle. • The sensitivity analysis to the ambient temperature was completed. - Abstract: Gas turbines are widely used in distributed power generation because of their high efficiency, low pollution and low operational cost. To further utilize the waste heat from gas turbines, an organic Rankine cycle (ORC) was proposed as the bottoming cycle for gas turbines in this paper. Two recuperators were coupled with the combined cycle to increase the thermal efficiency, and aromatics were chosen as the working fluid for the bottoming cycle. This paper focused on the optimum design and thermodynamic analysis of the gas turbine and ORC (GT-ORC) combined cycle. Results showed that the net power and thermal efficiency of the ORC increased with the ORC turbine inlet pressure and achieved optimum values at a specific pressure based on the optimum criteria. Furthermore, compared with the GT-Rankine combined cycle, the GT-ORC combined cycle had better thermodynamic performance. Toluene was a more suitable working fluid for the GT-ORC combined cycle. Moreover, ambient temperature sensitivity simulations concluded that the GT-ORC combined cycle had a maximum thermal efficiency and the combined cycle net power was mainly determined by the topping gas turbine cycle.

  15. Thermodynamic Modeling for Open Combined Regenerative Brayton and Inverse Brayton Cycles with Regeneration before the Inverse Cycle

    Directory of Open Access Journals (Sweden)

    Lingen Chen

    2012-01-01

    Full Text Available A thermodynamic model of an open combined regenerative Brayton and inverse Brayton cycles with regeneration before the inverse cycle is established in this paper by using thermodynamic optimization theory. The flow processes of the working fluid with the pressure drops and the size constraint of the real power plant are modeled. There are 13 flow resistances encountered by the working fluid stream for the cycle model. Four of these, the friction through the blades and vanes of the compressors and the turbines, are related to the isentropic efficiencies. The remaining nine flow resistances are always present because of the changes in flow cross-section at the compressor inlet of the top cycle, regenerator inlet and outlet, combustion chamber inlet and outlet, turbine outlet of the top cycle, turbine outlet of the bottom cycle, heat exchanger inlet, and compressor inlet of the bottom cycle. These resistances associated with the flow through various cross-sectional areas are derived as functions of the compressor inlet relative pressure drop of the top cycle, and control the air flow rate, the net power output and the thermal efficiency. The analytical formulae about the power output, efficiency and other coefficients are derived with 13 pressure drop losses. It is found that the combined cycle with regenerator can reach higher thermal efficiency but smaller power output than those of the base combined cycle at small compressor inlet relative pressure drop of the top cycle.

  16. Combined heat and power unit using renewable raw materials. A cogeneration power plant with wood chips and pellets; BHKW auf Basis nachwachsender Rohstoffe. KWK mit Holzhackschnitzeln und Pellets

    Energy Technology Data Exchange (ETDEWEB)

    Lennartz, Marc Wilhelm

    2013-07-15

    The combined heat and power units of the next generation operate with renewable resources. The plants working with wood chips or pellets now are ready for mass production. So, farmers and foresters, trade and municipalities may pile in the decentralized, energetic self-sufficiency. Two companies have developed procedures with which combined heat and power plants based can be operated on wood chips or pellets.

  17. Exergoeconomic improvement of a complex cogeneration system integrated with a professional process simulator

    International Nuclear Information System (INIS)

    Vieira, Leonardo S.; Donatelli, Joao L.; Cruz, Manuel E.

    2009-01-01

    In this paper, the application of an iterative exergoeconomic methodology for improvement of thermal systems to a complex combined-cycle cogeneration plant is presented. The methodology integrates exergoeconomics with a professional process simulator, and represents an alternative to conventional mathematical optimization techniques, because it reduces substantially the number of variables to be considered in the improvement process. By exploiting the computational power of a simulator, the integrated approach permits the optimization routine to ignore the variables associated with the thermodynamic equations, and thus to deal only with the economic equations and objective function. In addition, the methodology combines recent available exergoeconomic techniques with qualitative and quantitative criteria to identify only those decision variables, which matter for the improvement of the system. To demonstrate the strengths of the methodology, it is here applied to a 24-component cogeneration plant, which requires O(10 3 ) variables for its simulation. The results which are obtained, are compared to those reached using a conventional mathematical optimization procedure, also coupled to the process simulator. It is shown that, for engineering purposes, improvement of the system is often more cost effective and less time consuming than optimization of the system.

  18. Model Predictive Control of Integrated Gasification Combined Cycle Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    B. Wayne Bequette; Priyadarshi Mahapatra

    2010-08-31

    The primary project objectives were to understand how the process design of an integrated gasification combined cycle (IGCC) power plant affects the dynamic operability and controllability of the process. Steady-state and dynamic simulation models were developed to predict the process behavior during typical transients that occur in plant operation. Advanced control strategies were developed to improve the ability of the process to follow changes in the power load demand, and to improve performance during transitions between power levels. Another objective of the proposed work was to educate graduate and undergraduate students in the application of process systems and control to coal technology. Educational materials were developed for use in engineering courses to further broaden this exposure to many students. ASPENTECH software was used to perform steady-state and dynamic simulations of an IGCC power plant. Linear systems analysis techniques were used to assess the steady-state and dynamic operability of the power plant under various plant operating conditions. Model predictive control (MPC) strategies were developed to improve the dynamic operation of the power plants. MATLAB and SIMULINK software were used for systems analysis and control system design, and the SIMULINK functionality in ASPEN DYNAMICS was used to test the control strategies on the simulated process. Project funds were used to support a Ph.D. student to receive education and training in coal technology and the application of modeling and simulation techniques.

  19. Life cycle assessment of a biomass gasification combined-cycle power system

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.

    1997-12-01

    The potential environmental benefits from biomass power are numerous. However, biomass power may also have some negative effects on the environment. Although the environmental benefits and drawbacks of biomass power have been debated for some time, the total significance has not been assessed. This study serves to answer some of the questions most often raised in regard to biomass power: What are the net CO{sub 2} emissions? What is the energy balance of the integrated system? Which substances are emitted at the highest rates? What parts of the system are responsible for these emissions? To provide answers to these questions, a life cycle assessment (LCA) of a hypothetical biomass power plant located in the Midwest United States was performed. LCA is an analytical tool for quantifying the emissions, resource consumption, and energy use, collectively known as environmental stressors, that are associated with converting a raw material to a final product. Performed in conjunction with a technoeconomic feasibility study, the total economic and environmental benefits and drawbacks of a process can be quantified. This study complements a technoeconomic analysis of the same process, reported in Craig and Mann (1996) and updated here. The process studied is based on the concept of power Generation in a biomass integrated gasification combined cycle (BIGCC) plant. Broadly speaking, the overall system consists of biomass production, its transportation to the power plant, electricity generation, and any upstream processes required for system operation. The biomass is assumed to be supplied to the plant as wood chips from a biomass plantation, which would produce energy crops in a manner similar to the way food and fiber crops are produced today. Transportation of the biomass and other materials is by both rail and truck. The IGCC plant is sized at 113 MW, and integrates an indirectly-heated gasifier with an industrial gas turbine and steam cycle. 63 refs., 34 figs., 32 tabs.

  20. Life cycle assessment of a biomass gasification combined-cycle power system

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.

    1997-12-01

    The potential environmental benefits from biomass power are numerous. However, biomass power may also have some negative effects on the environment. Although the environmental benefits and drawbacks of biomass power have been debated for some time, the total significance has not been assessed. This study serves to answer some of the questions most often raised in regard to biomass power: What are the net CO{sub 2} emissions? What is the energy balance of the integrated system? Which substances are emitted at the highest rates? What parts of the system are responsible for these emissions? To provide answers to these questions, a life cycle assessment (LCA) of a hypothetical biomass power plant located in the Midwest United States was performed. LCA is an analytical tool for quantifying the emissions, resource consumption, and energy use, collectively known as environmental stressors, that are associated with converting a raw material to a final product. Performed in conjunction with a t echnoeconomic feasibility study, the total economic and environmental benefits and drawbacks of a process can be quantified. This study complements a technoeconomic analysis of the same process, reported in Craig and Mann (1996) and updated here. The process studied is based on the concept of power Generation in a biomass integrated gasification combined cycle (BIGCC) plant. Broadly speaking, the overall system consists of biomass production, its transportation to the power plant, electricity generation, and any upstream processes required for system operation. The biomass is assumed to be supplied to the plant as wood chips from a biomass plantation, which would produce energy crops in a manner similar to the way food and fiber crops are produced today. Transportation of the biomass and other materials is by both rail and truck. The IGCC plant is sized at 113 MW, and integrates an indirectly-heated gasifier with an industrial gas turbine and steam cycle. 63 refs., 34 figs., 32 tabs.

  1. The prospects of development of the market of cogeneration in Europe; Les perspectives de developpement du marche de la cogeneration eu Europe

    Energy Technology Data Exchange (ETDEWEB)

    Cotard, E. [Association Europeenne de Promotion de la Cogeneration, COGEN Europe (Country unknown/Code not available)

    1999-01-01

    Cogeneration or Combined Heat and Power has a high overall efficiency and brings about important environmental advantages in particular in terms of CO{sub 2} emissions. This win-win position is crucial at a time of widespread liberalization in energy markets. However, as shown by the various development rates within the EU, cogeneration is not equally treated across Europe. These differences are not only due to local climates - the development difference can ba as high as over 30% for example between France and The Netherlands. Nevertheless some recent European legislation such as the Gas and the Electricity Directives attempt to harmonize through liberalization. Liberalization should have positive aspects for cogeneration, in particular industrial cogeneration, provided that it is well designed and implemented. (authors)

  2. Parametric analysis for a new combined power and ejector-absorption refrigeration cycle

    International Nuclear Information System (INIS)

    Wang Jiangfeng; Dai Yiping; Zhang Taiyong; Ma Shaolin

    2009-01-01

    A new combined power and ejector-absorption refrigeration cycle is proposed, which combines the Rankine cycle and the ejector-absorption refrigeration cycle, and could produce both power output and refrigeration output simultaneously. This combined cycle, which originates from the cycle proposed by authors previously, introduces an ejector between the rectifier and the condenser, and provides a performance improvement without greatly increasing the complexity of the system. A parametric analysis is conducted to evaluate the effects of the key thermodynamic parameters on the cycle performance. It is shown that heat source temperature, condenser temperature, evaporator temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. It is evident that the ejector can improve the performance of the combined cycle proposed by authors previously.

  3. Tariffs for natural gas, electricity and cogeneration

    International Nuclear Information System (INIS)

    1995-02-01

    The rate of return of the combined generation of heat and power is not only determined by the capital expenditures and the costs of maintenance, control, management and insurances, but also by the fuel costs of the cogeneration installation and the avoided fuel costs in case of separated heat production, the avoided/saved costs of electricity purchase, and the compensation for possible supply to the public grid (sellback). This brochure aims at providing information about the structure of natural gas and electricity tariffs to be able to determine the three last-mentioned expenditures. First, attention is paid to the tariffs of natural gas for large-scale consumers, the tariff for cogeneration, and other tariffs. Next, the structure of the electricity tariffs is dealt with in detail, discussing the accounting system within the electric power sector, including the alterations in the National Basic Tariff and the Regional Basic Tariff (abbreviated in Dutch LBR, respectively RBT) per January 1, 1995, the compensations for large-scale consumers and specific large-scale consumers, electricity sellback tariffs, and compensations for reserve capacity. 7 figs., 5 tabs., 2 appendices, 7 refs

  4. Analysis of an optimal resorption cogeneration using mass and heat recovery processes

    International Nuclear Information System (INIS)

    Lu, Yiji; Wang, Yaodong; Bao, Huashan; Yuan, Ye; Wang, Liwei; Roskilly, Anthony Paul

    2015-01-01

    Highlights: • Resorption cogeneration for electricity and refrigeration generation. • Mass and heat recovery to further improve the performance. • The first and second law analysis. - Abstract: This paper presents an optimised resorption cogeneration using mass and heat recovery to improve the performance of a novel resorption cogeneration fist proposed by Wang et al. This system combines ammonia-resorption technology and expansion machine into one loop, which is able to generate refrigeration and electricity from low-grade heat sources such as solar energy and industrial waste heat. Two sets of resorption cycle are designed to overcome the intermittent performance of the chemisorption and produce continuous/simultaneous refrigeration and electricity. In this paper, twelve resorption working pairs of salt complex candidates are analysed by the first law analysis using Engineering Equation Solver (EES). The optimal resorption working pairs from the twelve candidates under the driven temperature from 100 °C to 300 °C are identified. By applying heat/mass recovery, the coefficient of performance (COP) improvement is increased by 38% when the high temperature salt (HTS) is NiCl 2 and by 35% when the HTS is MnCl 2 . On the other hand, the energy efficiency of electricity has also been improved from 8% to 12% with the help of heat/mass recovery. The second law analysis has also been applied to investigate the exergy utilisation and identify the key components/processes. The highest second law efficiency is achieved as high as 41% by the resorption working pair BaCl 2 –MnCl 2 under the heat source temperature at 110 °C.

  5. Improving the performances of gas turbines operated on natural gas in combined cycle power plants with application of mathematical models

    International Nuclear Information System (INIS)

    Dimkovski, Sasho

    2014-01-01

    The greater energy demand by today society sets a number of new challenges in the energy sector. The climate extremes impose new modes of operation of the power plants, with high flexibility in production. Combined cycle co generative power plants are the latest trend in the energy sector. Their high prevalence is due to the great efficiency and the good environmental characteristics. The main work horse in these cogeneration plants is the gas turbine, which power production and efficiency strongly depends on the external climate conditions. In warmer periods when there is increased demand for electricity, the power production from the gas turbines significantly declines. Because of the high electricity demand from the grid and reduced power production from the gas turbines at the same time, the need for application of appropriate technology for preserving the performances and power of the gas turbines arises. This master thesis explores different methods to improve the power in gas turbines by cooling the air on the compressor inlet, analyzing their applicability and effectiveness in order to choose the optimal method for power augmentation for the climatic conditions in the city Skopje. The master thesis gives detailed analysis of the weather in Skopje and the time frame in which the chosen method is applicable. At the end in the master thesis, the economic feasibility of the given method for power augmentation is clearly calculated, using a model of a power plant and calculating the resulting amount of gained energy, the amount of the initial investment, the cost for maintenance and operation of the equipment. By these calculations the period for initial return of investment is obtained. As an added benefit the positive environmental impacts of the applied technology for inlet air cooling is analyzed. (author)

  6. Pre-Combustion Carbondioxide Capture in Integrated Gasification Combined Cycles

    Directory of Open Access Journals (Sweden)

    M. Zeki YILMAZOĞLU

    2010-02-01

    Full Text Available Thermal power plants have a significant place big proportion in the production of electric energy. Thermal power plants are the systems which converts heat energy to mechanical energy and also mechanical energy to electrical energy. Heat energy is obtained from combustion process and as a result of this, some harmful emissions, like CO2, which are the reason for global warming, are released to atmosphere. The contribution of carbondioxide to global warming has been exposed by the previous researchs. Due to this fact, clean energy technologies are growing rapidly all around the world. Coal is generally used in power plants and when compared to other fossil energy sources unit electricity production cost is less than others. When reserve rate is taken into account, coal may be converted to energy in a more efficient and cleaner way. The aim for using the clean coal technologies are to eradicate the harmful emissions of coal and to store the carbondioxide, orginated from combustion, in different forms. In line with this aim, carbondioxide may be captured by either pre-combustion, by O2/CO2 recycling combustion systems or by post combustion. The integrated gasification combined cycles (IGCC are available in pre-combustion capture systems, whereas in O2/CO2 recycling combustion systems there are ultrasuper critical boiler technologies and finally flue gas washing systems by amines exists in post combustion systems. In this study, a pre-combustion CO2 capture process via oxygen blown gasifiers is compared with a conventional power plant in terms of CO2 emissions. Captured carbondioxide quantity has been presented as a result of the calculations made throughout the study.

  7. Cycle-by-cycle variations in a spark ignition engine fueled with natural gas-hydrogen blends combined with EGR

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Bin; Hu, Erjiang; Huang, Zuohua; Zheng, Jianjun; Liu, Bing; Jiang, Deming [State Key Laboratory of Multiphase Flow in Power Engineering, Xi' an Jiaotong University, 710049 Xi' an (China)

    2009-10-15

    Study of cycle-by-cycle variations in a spark ignition engine fueled with natural gas-hydrogen blends combined with exhaust gas recirculation (EGR) was conducted. The effects of EGR ratio and hydrogen fraction on engine cycle-by-cycle variations are analyzed. The results show that the cylinder peak pressure, the maximum rate of pressure rise and the indicated mean effective pressure decrease and cycle-by-cycle variations increase with the increase of EGR ratio. Interdependency between the above parameters and their corresponding crank angles of cylinder peak pressure is decreased with the increase of EGR ratio. For a given EGR ratio, combustion stability is promoted and cycle-by-cycle variations are decreased with the increase of hydrogen fraction in the fuel blends. Non-linear relationship is presented between the indicated mean effective pressure and EGR ratio. Slight influence of EGR ratio on indicated mean effective pressure is observed at low EGR ratios while large influence of EGR ratio on indicated mean effective pressure is demonstrated at high EGR ratios. The high test engine speed has lower cycle-by-cycle variations due to the enhancement of air flow turbulence and swirls in the cylinder. Increasing hydrogen fraction can maintain low cycle-by-cycle variations at high EGR ratios. (author)

  8. Cogeneration: A new opportunity for energy production market

    International Nuclear Information System (INIS)

    Minghetti, E.

    1997-03-01

    Cogeneration or Combined Heat and Power (CHP) is an advantageous technique based on the simultaneous utilisation of electricity and heat produced. For this purpose existing energetic technologies are used. Cogeneration is based on the thermodynamics principle that producing electricity by combustion process means, at the same time, producing waste heat that can be useful utilised. Three main advantages can be lay out in a cogeneration plant: 1. High efficiency (the global efficiency is often around 80-90%). 2. Economic profit (pay back time is usually not longer than 2-4 years). 3. Low pollutant emissions (as a consequence of the high efficiency less fuel is burned for generating the same quantity of electricity). In this report are analysed various aspects of cogeneration (technical and economical) and the conditions influencing is development. Some figures on the european and national situation are also given. Finally are presented the research and development activities carried out by Italian National Agency for new Technology Energy and the Environment Energy Department to improve the efficiency and the competitiveness of this technology

  9. Performance analysis of a stationary fuel cell thermoelectric cogeneration system

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, J.K.; Hwang, J.J.; Lin, C.H. [Department of Greenergy, National University of Tainan, Tainan, 70005 (China)

    2012-12-15

    The main purpose of our study was to use an experimental method and system dynamic simulation technology to examine a proton exchange membrane fuel cell thermoelectric cogeneration system that provides both high-quality electric power and heated water. In the second part of our study, we experimentally verified the development of key components of the fuel cell and conducted a comprehensive analysis of the subsystems, including the fuel cell module, hydrogen supply subsystem, air supply subsystem, humidifier subsystem, and heat recovery subsystem. Finally, we integrated all of the subsystems into a PEM fuel cell thermoelectric cogeneration system and performed efficiency tests and analysis of power generation, heat recovery, and thermoelectric cogeneration. After comparing this system's efficiency results using simulation and experimentation, we determined that the accuracy of the simulation values when compared to the experimental values was >95%, showing that this system's simulation nearly approached the efficiency of the actual experiment, including more than 53% for power generation efficiency, more than 39% for heat recovery efficiency, and more than 93% for thermoelectric cogeneration combined efficiency. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  10. Novel combined cycle configurations for propane pre-cooled mixed refrigerant (APCI) natural gas liquefaction cycle

    International Nuclear Information System (INIS)

    Mortazavi, Amir; Alabdulkarem, Abdullah; Hwang, Yunho; Radermacher, Reinhard

    2014-01-01

    Highlights: • 10 New LNG plants driver cycle enhancement configurations were developed. • All the 14 enhancement options design variables were optimized to demonstrate their energy saving potentials. • The best driver cycle enhancement option improved the driver cycle energy efficiency by 38%. • The effects of technological advancements on the performances of the enhancement options were studied. - Abstract: A significant amount of energy is required for natural gas liquefaction. Due to the production scale of LNG plants, they consume an intensive amount of energy. Consequently, any enhancement to the energy efficiency of LNG plants will result in a considerable reduction in natural gas consumption and CO 2 emission. Compressor drivers are the main energy consumer in the LNG plants. In this paper, 14 different driver cycle enhancement options were considered. A number of these options have not been proposed for the LNG plants. The new driver cycle development was performed by analyzing and optimizing the design variables of four conventional driver cycle enhancement options. The optimization results were used to develop more efficient cycles through mitigating the active constrains and driver cycle innovations. Based on the current available technologies five of our newly developed driver cycle configurations have higher efficiency than the most efficient existing conventional driver cycle. The best developed driver cycle enhancement option improved the base driver cycle energy efficiency by 38%. The effects of technological advancement on the performances of the all driver cycle enhancement options were also considered

  11. Cogeneration: Key feasibility analysis parameters

    International Nuclear Information System (INIS)

    Coslovi, S.; Zulian, A.

    1992-01-01

    This paper first reviews the essential requirements, in terms of scope, objectives and methods, of technical/economic feasibility analyses applied to cogeneration systems proposed for industrial plants in Italy. Attention is given to the influence on overall feasibility of the following factors: electric power and fuel costs, equipment coefficients of performance, operating schedules, maintenance costs, Italian Government taxes and financial and legal incentives. Through an examination of several feasibility studies that were done on cogeneration proposals relative to different industrial sectors, a sensitivity analysis is performed on the effects of varying the weights of different cost benefit analysis parameters. With the use of statistical analyses, standard deviations are then determined for key analysis parameters, and guidelines are suggested for analysis simplifications

  12. Cogeneration offers promise - politics permitting

    Energy Technology Data Exchange (ETDEWEB)

    Koprowski, Gene

    1996-12-01

    India`s Prime Minister H D Deve Gowda and the environmental activist Maneka Gandhi clashed recently over a US1.06 billion cogeneration power plant. Gandhi accused Gowda of moving too fast in giving the plant environmental clearance two days after assuming office. The argument, which delayed the start of a new thermal power plant by US-based Cogenetrix, illustrates the hazards of building such projects in Asia. (author)

  13. Critical review of the first-law efficiency in different power combined cycle architectures

    International Nuclear Information System (INIS)

    Iglesias Garcia, Steven; Ferreiro Garcia, Ramon; Carbia Carril, Jose; Iglesias Garcia, Denis

    2017-01-01

    Highlights: • The adiabatic expansion based TC can improve the energy efficiency of CCs. • A revolutionary TC can be a starting point to develop high-performance CCs. • A theoretical thermal efficiency of 83.7% was reached in a Nuclear Power Plant using a TC as bottoming cycle. - Abstract: This critical review explores the potential of an innovative trilateral thermodynamic cycle used to transform low-grade heat into mechanical work and compares its performance with relevant traditional thermodynamic cycles in combined cycles. The aim of this work is to show that combined cycles use traditional low efficiency power cycles in their bottoming cycle, and to evaluate theoretically the implementation of alternative power bottoming cycles. Different types of combined cycles have been reviewed, highlighting their relevant characteristics. The efficiencies of power plants using combined cycles are reviewed and compared. The relevance of researching thermodynamic cycles for combined cycle applications is that a vast amount of heat energy is available at negligible cost in the bottoming cycle of a combined cycle, with the drawback that existing thermal cycles cannot make efficient use of such available low temperature heat due to their low efficiency. The first-law efficiency is used as a parameter to compare and suggest improvements in the combined cycles (CCs) reviewed. The analysis shows that trilateral cycles using closed processes are by far the most efficient published thermal cycles for combined cycles to transform low-grade heat into mechanical work. An innovative trilateral bottoming cycle is proposed to show that the application of non-traditional power cycles can increase significantly the first-law efficiency of CCs. The highest first-law efficiencies achieved are: 85.55% in a CC using LNG cool, 73.82% for a transport vehicle CC, 74.40% in a marine CC, 83.07% in a CC for nuclear power plants, 73.82% in a CC using Brayton and Rankine cycles, 78.31% in a CC

  14. Comparative economic evaluation of environmental impact of different cogeneration technologies

    International Nuclear Information System (INIS)

    Patrascu, Roxana; Athanasovici, Victor; Raducanu, Cristian; Minciuc, Eduard; Bitir-Istrate, Ioan

    2004-01-01

    Cogeneration is one of the most powerful technologies for reduction of environmental pollution along with renewable energies. At the Kyoto Conference cogeneration has been identified as being the most important measure for reducing emissions of greenhouse effect gases. It has also been mentioned that cogeneration has a potential of reducing pollution with about 180 million tones per year. In order to promote new cogeneration technologies and evaluate the existing ones it is necessary to know and to be able to quantify in economical terms the environmental issues. When comparing different cogeneration technologies: steam turbine (TA), gas turbine (TG), internal combustion engine (MT), in order to choose the best one, the final decision implies an economic factor, which is even more important if it includes the environmental issues. The environmental impact of different cogeneration technologies is quantified using different criteria: depletion of non-renewable natural resources, eutrofisation, greenhouse effect, acidification etc. Environmental analysis using these criteria can be made using the 'impact with impact' methodology or the global one. The results of such an analysis cannot be quantified economically directly. Therefore there is a need of internalisation of ecological effects within the costs of produced energy: electricity and heat. In the energy production sector the externalizations represent the indirect effects on the environment. They can be materialised within different types of environmental impact: - Different buildings of mines, power plants etc; - Fuel losses during transportation and processing; - Effect of emissions in the air, water and soil. Introduction of the environmental impact costs in the energy price is called internalisation and it can be made using the direct and indirect methods. The paper discusses aspects regarding the emissions of cogeneration systems, the eco-taxes - method of 'internalisation' of environmental

  15. Parametric analysis and optimization for a combined power and refrigeration cycle

    International Nuclear Information System (INIS)

    Wang Jiangfeng; Dai Yiping; Gao Lin

    2008-01-01

    A combined power and refrigeration cycle is proposed, which combines the Rankine cycle and the absorption refrigeration cycle. This combined cycle uses a binary ammonia-water mixture as the working fluid and produces both power output and refrigeration output simultaneously with only one heat source. A parametric analysis is conducted to evaluate the effects of thermodynamic parameters on the performance of the combined cycle. It is shown that heat source temperature, environment temperature, refrigeration temperature, turbine inlet pressure, turbine inlet temperature, and basic solution ammonia concentration have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. A parameter optimization is achieved by means of genetic algorithm to reach the maximum exergy efficiency. The optimized exergy efficiency is 43.06% under the given condition

  16. Optimal operation of cogeneration units. State of art and perspective

    International Nuclear Information System (INIS)

    Polimeni, S.

    2001-01-01

    Optimal operation of cogeneration plants and of power plant fueling waste products is a complex challenge as they have to fulfill, beyond the contractual obligation of electric power supply, the constraints of supplying the required thermal energy to the user (for cogeneration units) or to burn completely the by-products of the industrial complex where they are integrated. Electrical power market evolution is pushing such units to a more and more volatile operation caused by uncertain selling price levels. This work intends to pinpoint the state of art in the optimization of these units outlining the important differences among the different size and cycles. The effect of the market liberalization on the automation systems and the optimization algorithms will be discussed [it

  17. Mini/micro cogeneration, basis for installation. Dimensioning, accounting and potential. Project report 1; Mini/mikrokraftvarme, forudsaetninger for installation. Dimensionering, afregningsforhold og potentiale. Projektrapport 1

    Energy Technology Data Exchange (ETDEWEB)

    Wit, J. de; Iskov, H.

    2005-11-15

    Cogeneration is quite spread in Denmark. Approx. 50 % of the power supply and 80 % of the district heating supply come from cogeneration. Combined heat and power is produced on both centralized (large) plants and decentralized plants. Decentralized combined heat and power plants (typically based on natural gas) use gas motors or gas turbines for power and heat production. Cogeneration of heat and power saves primary fuels and a directly derived effect from cogeneration is CO{sub 2} emission reduction. If fuels with higher specific CO{sub 2} emission than natural gas (e.g. coal, oil) are substituted, additional CO{sub 2} reduction can be reached. (BA)

  18. Integrated biomass gasification combined cycle distributed generation plant with reciprocating gas engine and ORC

    International Nuclear Information System (INIS)

    Kalina, Jacek

    2011-01-01

    The paper theoretically investigates the performance of a distributed generation plant made up of gasifier, Internal Combustion Engine (ICE) and Organic Rankine Cycle (ORC) machine as a bottoming unit. The system can be used for maximization of electricity production from biomass in the case where there is no heat demand for cogeneration plant. To analyze the performance of the gasifier a model based on the thermodynamic equilibrium approach is used. Performance of the gas engine is estimated on the basis of the analysis of its theoretical thermodynamic cycle. Three different setups of the plant are being examined. In the first one the ORC module is driven only by the heat recovered from engine exhaust gas and cooling water. Waste heat from a gasifier is used for gasification air preheating. In the second configuration a thermal oil circuit is applied. The oil transfers heat from engine and raw gas cooler into the ORC. In the third configuration it is proposed to apply a double cascade arrangement of the ORC unit with a two-stage low temperature evaporation of working fluid. This novel approach allows utilization of the total waste heat from the low temperature engine cooling circuit. Two gas engines of different characteristics are taken into account. The results obtained were compared in terms of electric energy generation efficiency of the system. The lowest obtained value of the efficiency was 23.6% while the highest one was 28.3%. These are very favorable values in comparison with other existing small and medium scale biomass-fuelled power generation plants. - Highlights: →The study presents performance analysis of a biomass-fuelled local power plant. →Downdraft wood gasifier, gas engine and ORC module are modelled theoretically. →Method for estimation of the producer gas fired engine performance is proposed. →Two gas engines of different characteristics are taken into account. →Different arrangements of the bottoming ORC cycle ere examined.

  19. Gasification integrated to combined cycles; Gasificacion integrada a ciclos combinados

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez M, Manuel F; Alcaraz C, Agustin M [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2001-07-01

    The mineral coal is one of the most abundant fuels in the planet, but it has important amounts of sulfur and ashes that make difficult their use. On the other hand, many countries at the present time prevent to use the fuel oil as combustible with conventional technologies due to the metal and sulfur contents. Finally, in the new schemes of oil refinement it is anticipated to use the coking to take advantage of the barrel bottoms. The remainder product of this process, known as refinery coke, has a low commercial value, a high calorific power and high sulfur content and metals. The gasification has been developed in the last the two decades, in the highly industrialized countries, as an alternative for the efficient and clean generation of electricity from dirty fuels, as well as for obtaining certain fuels in places where access to petroleum is not available, but to the coal. This technology fulfills the strictest regulations of the world in what polluting emissions refers and it is the only solution, next to the fluidized beds, for the problems that present some fuels that are difficult to burn with conventional technologies, as the mineral coal, the petroleum coke and even the liquid remainders of the refinement. With base in the former, it is possible to think about the integration of this technology to a combined cycle plant for the generation of electricity or to a refinery generating steam, electrical energy, hydrogen and other consumables at a competitive cost, in such a way that the problems of handling and storage of the remainders are solved; on the other hand the use of the primary power resources in the country is maximized. [Spanish] El carbon mineral es uno de los combustibles mas abundantes en el planeta, pero posee cantidades importantes de azufre y cenizas que dificultan su utilizacion. Por otra parte, muchos paises en la actualidad impiden utilizar el combustoleo como combustible para tecnologias convencionales debido a los contenidos de azufre y

  20. Energy and exergy analysis of a closed Brayton cycle-based combined cycle for solar power tower plants

    International Nuclear Information System (INIS)

    Zare, V.; Hasanzadeh, M.

    2016-01-01

    Highlights: • A novel combined cycle is proposed for solar power tower plants. • The effects of solar subsystem and power cycle parameters are examined. • The proposed combined cycle yields exergy efficiencies of higher than 70%. • For the overall power plant exergy efficiencies of higher than 30% is achievable. - Abstract: Concentrating Solar Power (CSP) technology offers an interesting potential for future power generation and research on CSP systems of all types, particularly those with central receiver system (CRS) has been attracting a lot of attention recently. Today, these power plants cannot compete with the conventional power generation systems in terms of Levelized Cost of Electricity (LCOE) and if a competitive LCOE is to be reached, employing an efficient thermodynamic power cycle is deemed essential. In the present work, a novel combined cycle is proposed for power generation from solar power towers. The proposed system consists of a closed Brayton cycle, which uses helium as the working fluid, and two organic Rankine cycles which are employed to recover the waste heat of the Brayton cycle. The system is thermodynamically assessed from both the first and second law viewpoints. A parametric study is conducted to examine the effects of key operating parameters (including solar subsystem and power cycle parameters) on the overall power plant performance. The results indicate that exergy efficiencies of higher than 30% are achieved for the overall power plant. Also, according to the results, the power cycle proposed in this work has a better performance than the other investigated Rankine and supercritical CO_2 systems operating under similar conditions, for these types of solar power plants.

  1. A combined thermodynamic cycle used for waste heat recovery of internal combustion engine

    International Nuclear Information System (INIS)

    He, Maogang; Zhang, Xinxin; Zeng, Ke; Gao, Ke

    2011-01-01

    In this paper, we present a steady-state experiment, energy balance and exergy analysis of exhaust gas in order to improve the recovery of the waste heat of an internal combustion engine (ICE). Considering the different characteristics of the waste heat of exhaust gas, cooling water, and lubricant, a combined thermodynamic cycle for waste heat recovery of ICE is proposed. This combined thermodynamic cycle consists of two cycles: the organic Rankine cycle (ORC), for recovering the waste heat of lubricant and high-temperature exhaust gas, and the Kalina cycle, for recovering the waste heat of low-temperature cooling water. Based on Peng–Robinson (PR) equation of state (EOS), the thermodynamic parameters in the high-temperature ORC were calculated and determined via an in-house computer program. Suitable working fluids used in high-temperature ORC are proposed and the performance of this combined thermodynamic cycle is analyzed. Compared with the traditional cycle configuration, more waste heat can be recovered by the combined cycle introduced in this paper. -- Highlights: ► We study the energy balance of fuel in internal combustion engine. ► Heat recovery effect of exhaust gas is good when ICE is at a high-load condition. ► We propose a new combined thermodynamic cycle for waste heat of ICE. ► The combined cycle has a higher recovery efficiency than previous configurations.

  2. THERMODYNAMIC ANALYSIS AND SIMULATION OF A NEW COMBINED POWER AND REFRIGERATION CYCLE USING ARTIFICIAL NEURAL NETWORK

    Directory of Open Access Journals (Sweden)

    Hossein Rezvantalab

    2011-01-01

    Full Text Available In this study, a new combined power and refrigeration cycle is proposed, which combines the Rankine and absorption refrigeration cycles. Using a binary ammonia-water mixture as the working fluid, this combined cycle produces both power and refrigeration output simultaneously by employing only one external heat source. In order to achieve the highest possible exergy efficiency, a secondary turbine is inserted to expand the hot weak solution leaving the boiler. Moreover, an artificial neural network (ANN is used to simulate the thermodynamic properties and the relationship between the input thermodynamic variables on the cycle performance. It is shown that turbine inlet pressure, as well as heat source and refrigeration temperatures have significant effects on the net power output, refrigeration output and exergy efficiency of the combined cycle. In addition, the results of ANN are in excellent agreement with the mathematical simulation and cover a wider range for evaluation of cycle performance.

  3. Modular cogeneration for commercial light industrial sector

    Energy Technology Data Exchange (ETDEWEB)

    Sakhuja, R.

    1984-01-01

    An analysis of gas utilities' efforts to market small cogeneration systems could be helpful to entrepreneurs now venturing into this area. Orders have been placed with Thermo Electron, USA for 15 Tecogen modular cogeneration units. Applications range from an airline catering kitchen to a university swimming pool. 5 figures, 1 table.

  4. A Thermodynamic Analysis of Two Competing Mid-Sized Oxyfuel Combustion Combined Cycles

    Directory of Open Access Journals (Sweden)

    Egill Thorbergsson

    2016-01-01

    Full Text Available A comparative analysis of two mid-sized oxyfuel combustion combined cycles is performed. The two cycles are the semiclosed oxyfuel combustion combined cycle (SCOC-CC and the Graz cycle. In addition, a reference cycle was established as the basis for the analysis of the oxyfuel combustion cycles. A parametric study was conducted where the pressure ratio and the turbine entry temperature were varied. The layout and the design of the SCOC-CC are considerably simpler than the Graz cycle while it achieves the same net efficiency as the Graz cycle. The fact that the efficiencies for the two cycles are close to identical differs from previously reported work. Earlier studies have reported around a 3% points advantage in efficiency for the Graz cycle, which is attributed to the use of a second bottoming cycle. This additional feature is omitted to make the two cycles more comparable in terms of complexity. The Graz cycle has substantially lower pressure ratio at the optimum efficiency and has much higher power density for the gas turbine than both the reference cycle and the SCOC-CC.

  5. Cogeneration in large processing power stations; Cogeneracion en grandes centrales de proceso

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, Jose Manuel [Observatorio Ciudadano de la Energia A. C., (Mexico)

    2004-06-15

    In this communication it is spoken of the cogeneration in large processing power stations with or without electricity surplus, the characteristics of combined cycle power plants and a comparative analysis in a graph entitled Sale price of electricity in combined cycle and cogeneration power plants. The industrial plants, such as refineries, petrochemical, breweries, paper mills and cellulose plants, among others, with steam necessities for their processes, have the technical and economical conditions to cogenerate, that is, to produce steam and electricity simultaneously. In fact, many of such facilities that exist at the moment in any country, count on cogeneration equipment that allows them to obtain their electricity at a very low cost, taking advantage of the existence steam generators that anyway are indispensable to satisfy their demand. In Mexico, given the existing legal frame, the public services of electricity as well as the oil industry are activities of obligatory character for the State. For these reasons, the subject should be part of the agenda of planning of this power sector. The opportunities to which we are referring to, are valid for the small industries, but from the point of view of the national interest, they are more important for the large size facilities and in that rank, the most numerous are indeed in PEMEX, whereas large energy surplus and capacity would result into cogenerations in refineries and petrochemical facilities and they would be of a high value, precisely for the electricity public service, that is, for the Comision Federal de Electricidad (CFE). [Spanish] En esta ponencia se habla de la cogeneracion en grandes centrales de proceso con o sin excedentes de electricidad, las caracteristicas de plantas de ciclo combinado y se muestra el analisis comparativo en una grafica titulada precio de venta de electricidad en plantas de ciclo combinado y de cogeneracion. Las plantas industriales, tales como refinerias, petroquimicas

  6. Tax issues in structuring effective cogeneration vehicles

    International Nuclear Information System (INIS)

    Yukich, J.M.

    1999-01-01

    A general overview of the Canadian income tax laws under which cogeneration plants will operate was presented. Highlights of some of the more important tax issues associated with cogeneration operations were included. This includes some of the specific rules dealing with the availability of the Manufacturing and Processing tax, credit, capital cost allowance, the Specified Energy Property rules and the tax treatment of Canadian Renewable and Conservation Expenses including the ability of a company to transfer such expenses to shareholders. Since it is expected that future cogeneration plants will have more than one owner, this paper reviewed the various legal structures through which multiple owners can own and run their cogeneration operations. Tax considerations related to the scale of a cogeneration plant were also reviewed

  7. Cogeneration development and market potential in China

    Energy Technology Data Exchange (ETDEWEB)

    Yang, F.; Levine, M.D.; Naeb, J. [Lawrence Berkeley Lab., CA (United States); Xin, D. [State Planning Commission of China, Beijing, BJ (China). Energy Research Inst.

    1996-05-01

    China`s energy production is largely dependent on coal. China currently ranks third in global CO{sub 2} emissions, and rapid economic expansion is expected to raise emission levels even further in the coming decades. Cogeneration provides a cost-effective way of both utilizing limited energy resources and minimizing the environmental impacts from use of fossil fuels. However, in the last 10 years state investments for cogeneration projects in China have dropped by a factor of 4. This has prompted this study. Along with this in-depth analysis of China`s cogeneration policies and investment allocation is the speculation that advanced US technology and capital can assist in the continued growth of the cogeneration industry. This study provides the most current information available on cogeneration development and market potential in China.

  8. A combined thermodynamic cycle based on methanol dissociation for IC (internal combustion) engine exhaust heat recovery

    International Nuclear Information System (INIS)

    Fu, Jianqin; Liu, Jingping; Xu, Zhengxin; Ren, Chengqin; Deng, Banglin

    2013-01-01

    In this paper, a novel approach for exhaust heat recovery was proposed to improve IC (internal combustion) engine fuel efficiency and also to achieve the goal for direct usage of methanol as IC engine fuel. An open organic Rankine cycle system using methanol as working medium is coupled to IC engine exhaust pipe for exhaust heat recovery. In the bottom cycle, the working medium first undergoes dissociation and expansion processes, and is then directed back to IC engine as fuel. As the external bottom cycle and the IC engine main cycle are combined together, this scheme forms a combined thermodynamic cycle. Then, this concept was applied to a turbocharged engine, and the corresponding simulation models were built for both of the external bottom cycle and the IC engine main cycle. On this basis, the energy saving potential of this combined cycle was estimated by parametric analyses. Compared to the methanol vapor engine, IC engine in-cylinder efficiency has an increase of 1.4–2.1 percentage points under full load conditions, while the external bottom cycle can increase the fuel efficiency by 3.9–5.2 percentage points at the working pressure of 30 bar. The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points. - Highlights: • A combined thermodynamic cycle using methanol as working medium for IC engine exhaust heat recovery is proposed. • The external bottom cycle of exhaust heat recovery and IC engine working cycle are combined together. • IC engine fuel efficiency could be improved from both in-cylinder working cycle and external bottom cycle. • The maximum improvement to the IC engine global fuel efficiency reaches 6.8 percentage points at full load

  9. Preliminary analysis of combined cycle of modular high-temperature gas cooled reactor

    International Nuclear Information System (INIS)

    Baogang, Z.; Xiaoyong, Y.; Jie, W.; Gang, Z.; Qian, S.

    2015-01-01

    Modular high-temperature gas cooled reactor (HTGR) is known as one of the most advanced nuclear reactors because of its inherent safety and high efficiency. The power conversion system of HTGR can be steam turbine based on Rankine cycle or gas turbine based on Brayton cycle respectively. The steam turbine system is mature and the gas turbine system has high efficiency but under development. The Brayton-Rankine combined cycle is an effective way to further promote the efficiency. This paper investigated the performance of combined cycle from the viewpoint of thermodynamics. The effect of non-dimensional parameters on combined cycle’s efficiency, such as temperature ratio, compression ratio, efficiency of compressor, efficiency of turbine, was analyzed. Furthermore, the optimal parameters to achieve highest efficiency was also given by this analysis under engineering constraints. The conclusions could be helpful to the design and development of combined cycle of HTGR. (author)

  10. Thermoeconomic analysis of a power/water cogeneration plant

    International Nuclear Information System (INIS)

    Hamed, Osman A.; Al-Washmi, Hamed A.; Al-Otaibi, Holayil A.

    2006-01-01

    Cogeneration plants for simultaneous production of water and electricity are widely used in the Arabian Gulf region. They have proven to be more thermodynamically efficient and economically feasible than single purpose power generation and water production plants. Yet, there is no standard or universally applied methodology for determining unit cost of electric power generation and desalinated water production by dual purpose plants. A comprehensive literature survey to critically assess and evaluate different methods for cost application in power/water cogeneration plants is reported in this paper. Based on this analysis, an in-depth thermoeconomic study is carried out on a selected power/water cogeneration plant that employs a regenerative Rankine cycle. The system incorporates a boiler, back pressure turbine (supplying steam to two MSF distillers), a deaerator and two feed water heaters. The turbine generation is rated at 118 MW, while MSF distiller is rated at 7.7 MIGD at a top brine temperature of 105 deg. C. An appropriate costing procedure based on the available energy accounting method which divides benefits of the cogeneration configuration equitably between electricity generation and water production is used to determine the unit costs of electricity and water. Capital charges of common equipment such as the boiler, deaerator and feed water heaters as well as boiler fuel costs are distributed between power generated and desalinated water according to available energy consumption of the major subsystems. A detailed sensitivity analysis was performed to examine the impact of the variation of fuel cost, load and availability factors in addition to capital recovery factor on electricity and water production costs

  11. Exergy analysis of parabolic trough solar collectors integrated with combined steam and organic Rankine cycles

    International Nuclear Information System (INIS)

    Al-Sulaiman, Fahad A.

    2014-01-01

    Highlights: • As the solar irradiation increases, the exergetic efficiency increases. • The R134a combined cycle has best exergetic performance, 26%. • The R600a combined cycle has the lowest exergetic efficiency, 20%. • The main source of exergy destruction is the solar collector. • There is an exergetic improvement potential of 75% in the systems considered. - Abstract: In this paper, detailed exergy analysis of selected thermal power systems driven by parabolic trough solar collectors (PTSCs) is presented. The power is produced using either a steam Rankine cycle (SRC) or a combined cycle, in which the SRC is the topping cycle and an organic Rankine cycle (ORC) is the bottoming cycle. Seven refrigerants for the ORC were examined: R134a, R152a, R290, R407c, R600, R600a, and ammonia. Key exergetic parameters were examined: exergetic efficiency, exergy destruction rate, fuel depletion ratio, irreversibility ratio, and improvement potential. For all the cases considered it was revealed that as the solar irradiation increases, the exergetic efficiency increases. Among the combined cycles examined, the R134a combined cycle demonstrates the best exergetic performance with a maximum exergetic efficiency of 26% followed by the R152a combined cycle with an exergetic efficiency of 25%. Alternatively, the R600a combined cycle has the lowest exergetic efficiency, 20–21%. This study reveals that the main source of exergy destruction is the solar collector where more than 50% of inlet exergy is destructed, or in other words more than 70% of the total destructed exergy. In addition, more than 13% of the inlet exergy is destructed in the evaporator which is equivalent to around 19% of the destructed exergy. Finally, this study reveals that there is an exergetic improvement potential of 75% in the systems considered

  12. A Geothermal Energy Supported Gas-steam Cogeneration Unit as a Possible Replacement for the Old Part of a Municipal CHP Plant (TEKO

    Directory of Open Access Journals (Sweden)

    L. Böszörményi

    2001-01-01

    Full Text Available The need for more intensive utilization of local renewable energy sources is indisputable. Under the current economic circumstances their competitiveness in comparison with fossil fuels is rather low, if we do not take into account environmental considerations. Integrating geothermal sources into combined heat and power production in a municipal CHP plant would be an excellent solution to this problem. This concept could lead to an innovative type of power plant - a gas-steam cycle based, geothermal energy supported cogeneration unit.

  13. Analysis of gas turbine cogeneration plants in Italy; Indagine sulla funzionalita` degli impianti di cogenerazione conturbina a gas operanti in Italia

    Energy Technology Data Exchange (ETDEWEB)

    Romani, Rino; Vignati, Sigfrido [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Energia

    1997-10-01

    The purpose of this study is to improve, by random analysis, the current knowledge about functional and running data of gas turbine cogeneration plants in Italy. The analysis consider simple and combined cycle gas turbines plant with electric power less 30.000 k W per unit and involves a sample of 44 units according to a randomized model consisting of 112 gas turbines. The collected data show different plant selection criteria, energy performances, reliability and availability values as well as maintenance costs. These data support some general suggestions and recommendations for a better selection and utilization of these plants.

  14. Thermodynamic efficiency analysis and cycle optimization of deeply precooled combined cycle engine in the air-breathing mode

    Science.gov (United States)

    Zhang, Jianqiang; Wang, Zhenguo; Li, Qinglian

    2017-09-01

    The efficiency calculation and cycle optimization were carried out for the Synergistic Air-Breathing Rocket Engine (SABRE) with deeply precooled combined cycle. A component-level model was developed for the engine, and exergy efficiency analysis based on the model was carried out. The methods to improve cycle efficiency have been proposed. The results indicate cycle efficiency of SABRE is between 29.7% and 41.7% along the flight trajectory, and most of the wasted exergy is occupied by the unburned hydrogen in exit gas. Exergy loss exists in each engine component, and the sum losses of main combustion chamber(CC), pre-burner(PB), precooler(PC) and 3# heat exchanger(HX3) are greater than 71.3% of the total loss. Equivalence ratio is the main influencing factor of cycle, and it can be regulated by adjusting parameters of helium loop. Increase the maximum helium outlet temperature of PC by 50 K, the total assumption of hydrogen will be saved by 4.8%, and the cycle efficiency is advanced by 3% averagely in the trajectory. Helium recirculation scheme introduces a helium recirculation loop to increase local helium flow rate of PC. It turns out the total assumption of hydrogen will be saved by 9%, that's about 1740 kg, and the cycle efficiency is advanced by 5.6% averagely.

  15. Towards an intermittency-friendly energy system: Comparing electric boilers and heat pumps in distributed cogeneration

    International Nuclear Information System (INIS)

    Blarke, Morten B.

    2012-01-01

    Highlights: ► We propose an “intermittency-friendly” energy system design. ► We compare intermittency-friendly concepts in distributed cogeneration. ► We investigate a new concept involving a heat pump and intermediate cold storage. ► We find significant improvements in operational intermittency-friendliness. ► Well-designed heat pump concepts are more cost-effective than electric boilers. -- Abstract: Distributed cogeneration has played a key role in the implementation of sustainable energy policies for three decades. However, increasing penetration levels of intermittent renewables is challenging that position. The paradigmatic case of West Denmark indicates that distributed operators are capitulating as wind power penetration levels are moving above 25%; some operators are retiring cogeneration units entirely, while other operators are making way for heat-only boilers. This development is jeopardizing the system-wide energy, economic, and environmental benefits that distributed cogeneration still has to offer. The solution is for distributed operators to adapt their technology and operational strategies to achieve a better co-existence between cogeneration and wind power. Four options for doing so are analysed including a new concept that integrates a high pressure compression heat pump using low-temperature heat recovered from flue gasses in combination with an intermediate cold storage, which enables the independent operation of heat pump and cogenerator. It is found that an electric boiler provides consistent improvements in the intermittency-friendliness of distributed cogeneration. However, well-designed heat pump concepts are more cost-effective than electric boilers, and in future markets where the gas/electricity price ratio is likely to increase, compression heat pumps in combination with intermediate thermal storages represent a superior potential for combining an intermittency-friendly pattern of operation with the efficient use of

  16. Tax issues in structuring effective cogeneration vehicles

    International Nuclear Information System (INIS)

    Ebel, S.R.

    1999-01-01

    An overview of the Canadian income tax laws that apply to cogeneration projects was presented. Certain tax considerations could be taken into account in deciding upon ownership and financing structures for cogeneration projects, particularly those that qualify for class 43.1 capital cost allowance treatment. The tax treatment of project revenues and expenses were described. The paper also reviewed the 1999 federal budget proposals regarding the manufacturing and processing tax credit, the capital cost allowance system applicable to cogeneration assets and the treatment of the Canadian renewable conservation expense

  17. Steam microturbines in distributed cogeneration

    CERN Document Server

    Kicinski, Jan

    2014-01-01

    This book presents the most recent trends and concepts in power engineering, especially with regard to prosumer and civic energy generation. In so doing, it draws widely on his experience gained during the development of steam microturbines for use in small combined heat and power stations based on the organic Rankine cycle (CHP-ORC). Major issues concerning the dynamic properties of mechanical systems, in particular rotating systems, are discussed, and the results obtained when using unconventional bearing systems, presented. Modeling and analysis of radial-flow and axial-flow microturbines a

  18. Combined Reverse-Brayton Joule Thompson Hydrogen Liquefaction Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Shimko, Martin A. [Gas Equipment Engineering Corporation, Milford, CT (United States); Dunn, Paul M. [Gas Equipment Engineering Corporation, Milford, CT (United States)

    2011-12-31

    The following is a compilation of Annual Progress Reports submitted to the DOE’s Fuel Cell Technologies Office by Gas Equipment Engineering Corp. for contract DE-FG36-05GO15021. The reports cover the project activities from August 2005 through June 2010. The purpose of this project is to produce a pilot-scale liquefaction plant that demonstrates GEECO’s ability to meet or exceed the efficiency targets set by the DOE. This plant will be used as a model to commercialize this technology for use in the distribution infrastructure of hydrogen fuel. It could also be applied to markets distributing hydrogen for industrial gas applications. Extensive modeling of plant performance will be used in the early part of the project to identify the liquefaction cycle architecture that optimizes the twin goals of increased efficiency and reduced cost. The major challenge of the project is to optimize/balance the performance (efficiency) of the plant against the cost of the plant so that the fully amortized cost of liquefying hydrogen meets the aggressive goals set by DOE. This project will design and build a small-scale pilot plant (several hundred kg/day) that will be both a hardware demonstration and a model for scaling to larger plant sizes (>50,000 kg/day). Though an effort will be made to use commercial or near-commercial components, key components that will need development for either a pilot- or full-scale plant will be identified. Prior to starting pilot plant fabrication, these components will be demonstrated at the appropriate scale to demonstrate sufficient performance for use in the pilot plant and the potential to achieve the performance used in modeling the full-scale plant.

  19. Combined cold compressor/ejector helium refrigerator cycle

    International Nuclear Information System (INIS)

    Schlafke, A.P.; Brown, D.P.; Wu, K.C.

    1984-01-01

    This chapter demonstrates how the use of a cold compressor in series with an ejector is an effective way to produce the desired low pressure in a helium refrigeration system. The cold compressor is tentatively located at the low pressure side below the J-T heat exchanger. The ejector is the first stage and the cold compressor is the second stage of the two-stage pumping system. A centrifugal, oil-bearing type compressor was installed on the R and D refrigerator at the Brookhaven National Laboratory. It is determined that the combined cold compressor and ejector system produces a lower temperature on the same load or more cooling at the same temperature compared with a system which uses an ejector alone. Results of the test showed a gain of 20%

  20. Comparative evaluation of hybrid systems of natural gas cogeneration and sugar cane bagasse; Avaliacao comparativa de sistemas hibridos de cogeracao a gas natutral e bagaco de cana

    Energy Technology Data Exchange (ETDEWEB)

    Zamboni, Leonardo Moneci; Tribess, Arlindo [Sao Paulo Univ., SP (Brazil). Escola Politecnica. Dept. de Engenharia Mecanica]. E-mail: leonardo.zamboni@poli.usp.br; atribess@usp.br

    2006-07-01

    The consumption of electricity in Brazil and mainly in the State of Sao Paulo is increasing gradually. On the other hand, the hydraulic potential is practically exhausted and the government has no resources for such new investments. One solution is the construction of thermo electrical plants with the use of the natural gas and sugar cane bagasse. The natural gas has the advantage of being available in great amount and less pollutant. And the sugar cane bagasse, besides being a by-product of low value, does not cause a global pollution. The work consists of the determination of the best option considering criterion of minimum cost for kWh of energy produced. For such, thermo economic analysis with electricity and steam production costs evaluation in exergetic basis, was accomplished. In the evaluations the consumption of natural gas and the costs of the sugar cane bagasse were varied. The results show that the cogeneration plant with combined cycle using natural gas and burning sugar cane bagasse in the recovery boiler presents the smallest cost of electricity and steam generation (even not being the cycle with larger exergetic efficiency). On the other hand, for a natural gas cost of 140 US$/t and a cost of sugar cane bagasse superior to 10,50 US$/t the cogeneration plant with combined cycle using only natural gas (and, therefore not burning or gasifying sugar cane bagasse) presented the smallest cost of electricity and steam generation. (author)

  1. SOLHYCO Project: cogeneration system with concentrated solar energy and biofuels; Projeto SOLHYCO: sistema de cogeracao de energia solar concentrada e biocombustiveis

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Celso Eduardo Lins de; Rabi, Jose Antonio; Carrer, Celso da Costa; Cavinatto, Betina; Tomasella, Peterson Ricardo [Universidade de Sao Paulo (FZEA-USP), SP (Brazil). Fac. de Zootecnia e Engenharia de Alimentos

    2008-07-01

    Dispatchable renewable power generation is usually associated with expensive storages or additional back-up systems. Solar-hybrid systems can combine solar energy with an additional fuel and thus reliably provide electric power. If renewable fuels (e.g., biofuels) are employed, power generation becomes 100% sustainable at zero net emissions. Systems based on gas turbines are suited for cogeneration or combined cycles, making them very efficient and cost effective. These cycles require high temperatures and pressures, thus the solar energy has to be concentrated by a heliostat field onto the top of a tower and transferred by a solar receiver into the gas turbine cycle. At smaller power levels, cogeneration of heat and power is an attractive option by making use of the high exhaust temperature of the gas turbine, thus getting an additional benefit. The aim of this proposal is an significant extension of the objectives of the recently started SOLHYCO project by means A profound knowledge for market introduction will be gained by the assessment of the Brazilian market concerning solar resources, biofuels, electricity markets, heat markets and social needs. A detailed design study for a first demonstration unit will deliver all necessary economical, social and environmental data and accordingly 3 case studies have been defined. (author)

  2. Waste-heat boiler application for the Vresova combined cycle plant

    Energy Technology Data Exchange (ETDEWEB)

    Vicek, Z. [Energoprojekt Praha, Prague (Czechoslovakia)

    1995-12-01

    This report describes a project proposal and implementation of two combined-cycle units of the Vresova Fuel Complex (PKV) with 2 x 200 MWe and heat supply. Participation of ENERGOPROJECT Praha a.s., in this project.

  3. Exergy analysis, parametric analysis and optimization for a novel combined power and ejector refrigeration cycle

    International Nuclear Information System (INIS)

    Dai Yiping; Wang Jiangfeng; Gao Lin

    2009-01-01

    A new combined power and refrigeration cycle is proposed, which combines the Rankine cycle and the ejector refrigeration cycle. This combined cycle produces both power output and refrigeration output simultaneously. It can be driven by the flue gas of gas turbine or engine, solar energy, geothermal energy and industrial waste heats. An exergy analysis is performed to guide the thermodynamic improvement for this cycle. And a parametric analysis is conducted to evaluate the effects of the key thermodynamic parameters on the performance of the combined cycle. In addition, a parameter optimization is achieved by means of genetic algorithm to reach the maximum exergy efficiency. The results show that the biggest exergy loss due to the irreversibility occurs in heat addition processes, and the ejector causes the next largest exergy loss. It is also shown that the turbine inlet pressure, the turbine back pressure, the condenser temperature and the evaporator temperature have significant effects on the turbine power output, refrigeration output and exergy efficiency of the combined cycle. The optimized exergy efficiency is 27.10% under the given condition.

  4. Thermodynamic analysis of heat recovery steam generator in combined cycle power plant

    Directory of Open Access Journals (Sweden)

    Ravi Kumar Naradasu

    2007-01-01

    Full Text Available Combined cycle power plants play an important role in the present energy sector. The main challenge in designing a combined cycle power plant is proper utilization of gas turbine exhaust heat in the steam cycle in order to achieve optimum steam turbine output. Most of the combined cycle developers focused on the gas turbine output and neglected the role of the heat recovery steam generator which strongly affects the overall performance of the combined cycle power plant. The present paper is aimed at optimal utilization of the flue gas recovery heat with different heat recovery steam generator configurations of single pressure and dual pressure. The combined cycle efficiency with different heat recovery steam generator configurations have been analyzed parametrically by using first law and second law of thermodynamics. It is observed that in the dual cycle high pressure steam turbine pressure must be high and low pressure steam turbine pressure must be low for better heat recovery from heat recovery steam generator.

  5. Estimating the power efficiency of the thermal power plant modernization by using combined-cycle technologies

    International Nuclear Information System (INIS)

    Hovhannisyan, L.S.; Harutyunyan, N.R.

    2013-01-01

    The power efficiency of the thermal power plant (TPP) modernization by using combined-cycle technologies is introduced. It is shown that it is possible to achieve the greatest decrease in the specific fuel consumption at modernizing the TPP at the expense of introducing progressive 'know-how' of the electric power generation: for TPP on gas, it is combined-cycle, gas-turbine superstructures of steam-power plants and gas-turbines with heat utilization

  6. Thermodynamic and economic analysis on geothermal integrated combined-cycle power plants

    International Nuclear Information System (INIS)

    Bettocchi, R.; Cantore, G.; Negri di Montenegro, G.; Gadda, E.

    1992-01-01

    This paper considers geothermal integrated power plants obtained matching a geothermal plant with, a two pressure level combined plant. The purpose of the paper is the evaluation of thermodynamic and economic aspects on geothermal integrated combined-cycle power plant and a comparison with conventional solutions. The results show that the integrated combined plant power is greater than the sum of combined cycle and geothermal plant powers considered separately and that the integrated plant can offer economic benefits reaching the 16% of the total capital required

  7. Performance evaluation of cogeneration power plants

    International Nuclear Information System (INIS)

    Bacone, M.

    2001-01-01

    The free market has changed the criteria for measuring the cogeneration plant performances. Further at the technical-economic parameters, are considered other connected at the profits of the power plant [it

  8. Comparative performance analysis of combined-cycle pulse detonation turbofan engines (PDTEs

    Directory of Open Access Journals (Sweden)

    Sudip Bhattrai

    2013-09-01

    Full Text Available Combined-cycle pulse detonation engines are promising contenders for hypersonic propulsion systems. In the present study, design and propulsive performance analysis of combined-cycle pulse detonation turbofan engines (PDTEs is presented. Analysis is done with respect to Mach number at two consecutive modes of operation: (1 Combined-cycle PDTE using a pulse detonation afterburner mode (PDA-mode and (2 combined-cycle PDTE in pulse detonation ramjet engine mode (PDRE-mode. The performance of combined-cycle PDTEs is compared with baseline afterburning turbofan and ramjet engines. The comparison of afterburning modes is done for Mach numbers from 0 to 3 at 15.24 km altitude conditions, while that of pulse detonation ramjet engine (PDRE is done for Mach 1.5 to Mach 6 at 18.3 km altitude conditions. The analysis shows that the propulsive performance of a turbine engine can be greatly improved by replacing the conventional afterburner with a pulse detonation afterburner (PDA. The PDRE also outperforms its ramjet counterpart at all flight conditions considered herein. The gains obtained are outstanding for both the combined-cycle PDTE modes compared to baseline turbofan and ramjet engines.

  9. The Mexican electricity industry - cogeneration potential

    International Nuclear Information System (INIS)

    Monroy, I.L.

    2000-01-01

    A brief history of Mexico's electric power industry is given. Diagrams show (i) the increase in primary energy production from 1990-1998; (ii) energy consumption by sector and (iii) the change in capacity between 1990 and 1998. The projected energy development for 1998-2007 is discussed. The Mexican government has chosen cogeneration to be an important contributor to future energy-efficient power production. Data on installed cogeneration capacity for years 2000 and 2001 are given according to sector

  10. CDM potential of bagasse cogeneration in India

    International Nuclear Information System (INIS)

    Purohit, Pallav; Michaelowa, Axel

    2007-01-01

    So far, the cumulative capacity of renewable energy systems such as bagasse cogeneration in India is far below their theoretical potential despite government subsidy programmes. One of the major barriers is the high investment cost of these systems. The Clean Development Mechanism (CDM) provides industrialized countries with an incentive to invest in emission reduction projects in developing countries to achieve a reduction in CO 2 emissions at lowest cost that also promotes sustainable development in the host country. Bagasse cogeneration projects could be of interest under the CDM because they directly displace greenhouse gas emissions while contributing to sustainable rural development. This study assesses the maximum theoretical as well as the realistically achievable CDM potential of bagasse cogeneration in India. Our estimates indicate that there is a vast theoretical potential of CO 2 mitigation by the use of bagasse for power generation through cogeneration process in India. The preliminary results indicate that the annual gross potential availability of bagasse in India is more than 67 million tonnes (MT). The potential of electricity generation through bagasse cogeneration in India is estimated to be around 34 TWh i.e. about 5575 MW in terms of the plant capacity. The annual CER potential of bagasse cogeneration in India could theoretically reach 28 MT. Under more realistic assumptions about diffusion of bagasse cogeneration based on past experiences with the government-run programmes, annual CER volumes by 2012 could reach 20-26 million. The projections based on the past diffusion trend indicate that in India, even with highly favorable assumptions, the dissemination of bagasse cogeneration for power generation is not likely to reach its maximum estimated potential in another 20 years. CDM could help to achieve the maximum utilization potential more rapidly as compared to the current diffusion trend if supportive policies are introduced

  11. Heating unit of Berovo by co-generation (Macedonia)

    International Nuclear Information System (INIS)

    Armenski, Slave; Dimitrov, Konstantin; Tashevski, Done

    1999-01-01

    A plant for combined heat and electric power production, for central heating of the town Berovo (Macedonia) is proposed. The common reason to use a co-generation unit is the energy efficiency and a significant reduction of environmental pollution. The heat consumption of town Berovo is analyzed and determined. Based on the energy consumption of a whole power plant, e. i. the plant for combined and simultaneous production of power is proposed. The quantity of annually heat and electrical production and annually coal consumption are estimated. (Author)

  12. Thermal cycle efficiency of the indirect combined HTGR-GT power generation system

    Energy Technology Data Exchange (ETDEWEB)

    Muto, Yasushi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-02-01

    High thermal efficiency of 50% could be expected in a power generation system coupling a high temperature gas-cooled reactor(HTGR) with a closed cycle gas turbine(GT). There are three candidate systems such as a direct cycle(DC), an indirect cycle(ICD) and an indirect combined cycle(IDCC). The IDCC could solve many problems in both the DC and the IDC and consists of a primary circuit and a secondary circuit where a topping cycle is a Brayton cycle and a bottoming cycle is a steam cycle. In this report, the thermal cycle efficiency of the IDCC is examined regarding configurations of components and steam pressure. It has been shown that there are two types of configurations, that is, a perfect cascade type and a semi-cascade one and the latter can be further classified into Case A, Case B and Case C. The conditions achieving the maximum thermal cycle efficiency were revealed for these cases. In addition, the optimum system configurations were proposed considering the thermal cycle efficiency, safety and plant arrangement. (author).

  13. Electricity transport regimes: their impact on cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Cotard, Erwan [COGEN, Europe (Belgium)

    2000-12-01

    In many cases the main product of cogeneration is heat and the surplus electricity is sold to the grid. However, the economics of cogeneration can be influenced by transport networks (transmission and distribution): the structure of network pricing is relatively new. In a recent note from COGEN Europe it was recommended that cogenerators who use only the local distribution system should not pay for the transmission system and that tariffs should be structured in sufficient detail for the advantages of decentralisation to be realised. The article is presented under the sub-headings of (i) why is this important? (the omission of the transmission element reduces the overall price of cogeneration); (ii) the advantages of decentralised cogeneration; (iv) the theory - the different systems (the European Directive on electricity market liberalization); (v) the options for transport fees; (vi) current regimes in some EU states (vii) the case of transborder transport; impact of each system on cogeneration; recommendations to policymakers; (viii) the Netherlands and (ix) the UK.

  14. A unified model of combined energy systems with different cycle modes and its optimum performance characteristics

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yue [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005 (China); College of Information Science and Engineering, Huaqiao University, Quanzhou 362021 (China); Hu, Weiqiang [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005 (China); Ou Congjie [College of Information Science and Engineering, Huaqiao University, Quanzhou 362021 (China); Chen Jincan [Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005 (China)], E-mail: jcchen@xmu.edu.cn

    2009-06-15

    A unified model is presented for a class of combined energy systems, in which the systems mainly consist of a heat engine, a combustor and a counter-flow heat exchanger and the heat engine in the systems may have different thermodynamic cycle modes such as the Brayton cycle, Carnot cycle, Stirling cycle, Ericsson cycle, and so on. Not only the irreversibilities of the heat leak and finite-rate heat transfer but also the different cycle modes of the heat engine are considered in the model. On the basis of Newton's law, expressions for the overall efficiency and power output of the combined energy system with an irreversible Brayton cycle are derived. The maximum overall efficiency and power output and other relevant parameters are calculated. The general characteristic curves of the system are presented for some given parameters. Several interesting cases are discussed in detail. The results obtained here are very general and significant and can be used to discuss the optimal performance characteristics of a class of combined energy systems with different cycle modes. Moreover, it is significant to point out that not only the important conclusions obtained in Bejan's first combustor model and Peterson's general combustion driven model but also the optimal performance of a class of solar-driven heat engine systems can be directly derived from the present paper under some limit conditions.

  15. A unified model of combined energy systems with different cycle modes and its optimum performance characteristics

    International Nuclear Information System (INIS)

    Zhang Yue; Hu, Weiqiang; Ou Congjie; Chen Jincan

    2009-01-01

    A unified model is presented for a class of combined energy systems, in which the systems mainly consist of a heat engine, a combustor and a counter-flow heat exchanger and the heat engine in the systems may have different thermodynamic cycle modes such as the Brayton cycle, Carnot cycle, Stirling cycle, Ericsson cycle, and so on. Not only the irreversibilities of the heat leak and finite-rate heat transfer but also the different cycle modes of the heat engine are considered in the model. On the basis of Newton's law, expressions for the overall efficiency and power output of the combined energy system with an irreversible Brayton cycle are derived. The maximum overall efficiency and power output and other relevant parameters are calculated. The general characteristic curves of the system are presented for some given parameters. Several interesting cases are discussed in detail. The results obtained here are very general and significant and can be used to discuss the optimal performance characteristics of a class of combined energy systems with different cycle modes. Moreover, it is significant to point out that not only the important conclusions obtained in Bejan's first combustor model and Peterson's general combustion driven model but also the optimal performance of a class of solar-driven heat engine systems can be directly derived from the present paper under some limit conditions

  16. A combined cycle utilizing LNG and low-temperature solar energy

    International Nuclear Information System (INIS)

    Rao, Wen-Ji; Zhao, Liang-Ju; Liu, Chao; Zhang, Mo-Geng

    2013-01-01

    This paper has proposed a combined cycle, in which low-temperature solar energy and cold energy of liquefied natural gas (LNG) can be effectively utilized together. Comparative analysis based on a same net work output between the proposed combined cycle and separated solar ORC and LNG vapor system has been done. The results show that, for the combined cycle, a decrease of nearly 82.2% on the area of solar collector is obtained and the area of heat exchanger decreases by 31.7%. Moreover, exergy efficiency is higher than both two separated systems. This work has also dealt with the thermodynamic analyses for the proposed cycle. The results show that R143a followed by propane and propene emerges as most suitable fluid. Moreover, with a regenerator added in the cycle, performance improvement is obtained for the reduction on area of solar collector and increase on system efficiency and exergy efficiency. -- Highlights: • A combined cycle utilizing low-temperature solar energy and LNG together is proposed. • Five objection functions are used to decide the best working fluids. • Cycle with a regenerator has good performance

  17. Estimate for interstage water injection in air compressor incorporated into gas-turbine cycles and combined power plants cycles

    Science.gov (United States)

    Kler, A. M.; Zakharov, Yu. B.; Potanina, Yu. M.

    2017-05-01

    The objects of study are the gas turbine (GT) plant and combined cycle power plant (CCPP) with opportunity for injection between the stages of air compressor. The objective of this paper is technical and economy optimization calculations for these classes of plants with water interstage injection. The integrated development environment "System of machine building program" was a tool for creating the mathematic models for these classes of power plants. Optimization calculations with the criterion of minimum for specific capital investment as a function of the unit efficiency have been carried out. For a gas-turbine plant, the economic gain from water injection exists for entire range of power efficiency. For the combined cycle plant, the economic benefit was observed only for a certain range of plant's power efficiency.

  18. Inventory of future power and heat production technologies. Partial report Boilers/Combustion/Steam cycle for district heating and cogeneration; Inventering av framtidens el- och vaermeproduktionstekniker. Delrapport Pannor/Foerbraenning/Aangcykel foer fjaerrvaerme och kraftvaerme

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Robert (AaF Process, Stockholm (Sweden))

    2008-12-15

    The energy market of today is turbulent and it is quite clear that big changes in the consumption pattern are going to occur, due to the expansion in Asia and the expected Climate Change. The EU has, as a first step, stated in a directive that the consumption of renewable energy in the heat and power sector should be increased to 20 % and in the transportation sector to 10 % by the year 2020, a target which is high above current levels in most of the EU countries. It is reasonable to believe the European demand of renewable energy will create a shortage of biomass and that the development and use of technology for energy production will therefore not only depend on what is technically possible. One scenario is that biomass is mainly used for the markets that have very few alternatives, such as the transportation sector and small scale CHP units. We have today a relatively high electrical consumption through a stable grid and district heating nets in almost all densely populated areas. Large high efficiency power plants combined with heat pump technology will probably prevent any significant expansion of the district heating nets. A third major net for gas distribution seems not to be a feasible solution. Local nets for production of biogas from wet waste for different purposes, including EvGT units with 55% efficiency may however be good solution for some areas. There are a number of cycles and technical solutions to increase the electrical efficiency which could be applied also on smaller plants. The total efficiency will however not increase, only the el/heat ratio and it is not obvious that the higher investment cost for indirect cycles, bottom cycles or extreme steam data in combination with the risk of lower availability is a feasible solution. Especially waste to energy plants, with their need of high utilisation time, are sensitive to long production interruptions. The existing heat sinks in Sweden will however be efficiently used for electrical production

  19. Optimised heat recovery steam generators for integrated solar combined cycle plants

    Science.gov (United States)

    Peterseim, Jürgen H.; Huschka, Karsten

    2017-06-01

    The cost of concentrating solar power (CSP) plants is decreasing but, due to the cost differences and the currently limited value of energy storage, implementation of new facilities is still slow compared to photovoltaic systems. One recognized option to lower cost instantly is the hybridization of CSP with other energy sources, such as natural gas or biomass. Various references exist for the combination of CSP with natural gas in combined cycle plants, also known as Integrated Solar Combined Cycle (ISCC) plants. One problem with current ISCC concepts is the so called ISCC crisis, which occurs when CSP is not contributing and cycle efficiency falls below efficiency levels of solely natural gas only fired combined cycle plants. This paper analyses current ISCC concepts and compares them with two optimised designs. The comparison is based on a Kuraymat type ISCC plant and shows that cycle optimization enables a net capacity increase of 1.4% and additional daily generation of up to 7.9%. The specific investment of the optimised Integrated Solar Combined Cycle plant results in a 0.4% cost increase, which is below the additional net capacity and daily generation increase.

  20. NOVEL GAS CLEANING/CONDITIONING FOR INTEGRATED GASIFICATION COMBINED CYCLE

    Energy Technology Data Exchange (ETDEWEB)

    Dennis A. Horazak; Richard A. Newby; Eugene E. Smeltzer; Rachid B. Slimane; P. Vann Bush; James L. Aderhold Jr; Bruce G. Bryan

    2005-12-01

    lower for the Filter-Reactor Novel Gas Cleaning processes than for the conventional processes, the improved power plant capacity results in the potential for significant reductions in the plant cost-of-electricity, about 4.5% for the Current Standards case, and more than 7% for the Future Standards case. For Methanol Synthesis, the Novel Gas Cleaning process scheme again shows the potential for significant advantages over the conventional gas cleaning schemes. The plant generating capacity is increased more than 7% and there is a 2.3%-point gain in plant thermal efficiency. The Total Capital Requirement is reduced by about 13% and the cost-of-electricity is reduced by almost 9%. For both IGCC Methanol Synthesis cases, there are opportunities to combine some of the filter-reactor polishing stages to simplify the process further to reduce its cost. This evaluation has devised plausible humid-gas cleaning schemes for the Filter-Reactor Novel Gas Cleaning process that might be applied in IGCC and Methanol Synthesis applications.

  1. Combined Brayton-JT cycles with refrigerants for natural gas liquefaction

    Science.gov (United States)

    Chang, Ho-Myung; Park, Jae Hoon; Lee, Sanggyu; Choe, Kun Hyung

    2012-06-01

    Thermodynamic cycles for natural gas liquefaction with single-component refrigerants are investigated under a governmental project in Korea, aiming at new processes to meet the requirements on high efficiency, large capacity, and simple equipment. Based upon the optimization theory recently published by the present authors, it is proposed to replace the methane-JT cycle in conventional cascade process with a nitrogen-Brayton cycle. A variety of systems to combine nitrogen-Brayton, ethane-JT and propane-JT cycles are simulated with Aspen HYSYS and quantitatively compared in terms of thermodynamic efficiency, flow rate of refrigerants, and estimated size of heat exchangers. A specific Brayton-JT cycle is suggested with detailed thermodynamic data for further process development. The suggested cycle is expected to be more efficient and simpler than the existing cascade process, while still taking advantage of easy and robust operation with single-component refrigerants.

  2. Multi-objective thermodynamic optimization of combined Brayton and inverse Brayton cycles using genetic algorithms

    International Nuclear Information System (INIS)

    Besarati, S.M.; Atashkari, K.; Jamali, A.; Hajiloo, A.; Nariman-zadeh, N.

    2010-01-01

    This paper presents a simultaneous optimization study of two outputs performance of a previously proposed combined Brayton and inverse Brayton cycles. It has been carried out by varying the upper cycle pressure ratio, the expansion pressure of the bottom cycle and using variable, above atmospheric, bottom cycle inlet pressure. Multi-objective genetic algorithms are used for Pareto approach optimization of the cycle outputs. The two important conflicting thermodynamic objectives that have been considered in this work are net specific work (w s ) and thermal efficiency (η th ). It is shown that some interesting features among optimal objective functions and decision variables involved in the Baryton and inverse Brayton cycles can be discovered consequently.

  3. Higher-capacity lithium ion battery chemistries for improved residential energy storage with micro-cogeneration

    International Nuclear Information System (INIS)

    Darcovich, K.; Henquin, E.R.; Kenney, B.; Davidson, I.J.; Saldanha, N.; Beausoleil-Morrison, I.

    2013-01-01

    Highlights: • Characterized two novel high capacity electrode materials for Li-ion batteries. • A numerical discharge model was run to characterize Li-ion cell behavior. • Engineering model of Li-ion battery pack developed from cell fundamentals. • ESP-r model integrated micro-cogeneration and high capacity Li-ion storage. • Higher capacity batteries shown to improve micro-cogeneration systems. - Abstract: Combined heat and power on a residential scale, also known as micro-cogeneration, is currently gaining traction as an energy savings practice. The configuration of micro-cogeneration systems is highly variable, as local climate, energy supply, energy market and the feasibility of including renewable type components such as wind turbines or photovoltaic panels are all factors. Large-scale lithium ion batteries for electrical storage in this context can provide cost savings, operational flexibility, and reduced stress on the distribution grid as well as a degree of contingency for installations relying upon unsteady renewables. Concurrently, significant advances in component materials used to make lithium ion cells offer performance improvements in terms of power output, energy capacity, robustness and longevity, thereby enhancing their prospective utility in residential micro-cogeneration installations. The present study evaluates annual residential energy use for a typical Canadian home connected to the electrical grid, equipped with a micro-cogeneration system consisting of a Stirling engine for supplying heat and power, coupled with a nominal 2 kW/6 kW h lithium ion battery. Two novel battery cathode chemistries, one a new Li–NCA material, the other a high voltage Ni-doped lithium manganate, are compared in the residential micro-cogeneration context with a system equipped with the presently conventional LiMn 2 O 4 spinel-type battery

  4. The History and Promise of Combined Cycle Engines for Access to Space Applications

    Science.gov (United States)

    Clark, Casie

    2010-01-01

    For the summer of 2010, I have been working in the Aerodynamics and Propulsion Branch at NASA Dryden Flight Research Center studying combined-cycle engines, a high speed propulsion concept. Combined cycle engines integrate multiple propulsion systems into a single engine capable of running in multiple modes. These different modes allow the engine to be extremely versatile and efficient in varied flight conditions. The two most common types of combined cycle engines are Rocket-Based Combined Cycle (RBCC) and Turbine Based Combined Cycle (TBCC). The RBCC essentially combines a rocket and ramjet engine, while the TBCC integrates a turbojet and ramjet1. These two engines are able to switch between different propulsion modes to achieve maximum performance. Extensive conceptual and ground test studies of RBCC engines have been undertaken; however, an RBCC engine has never, to my knowledge, been demonstrated in flight. RBCC engines are of particular interest because they could potentially power a reusable launch vehicle (RLV) into space. The TBCC has been flight tested and shown to be effective at reaching supersonic speeds, most notably in the SR-71 Blackbird2.

  5. Performance analysis of solar parabolic trough collectors driven combined supercritical CO2 and organic Rankine cycle

    Directory of Open Access Journals (Sweden)

    Harwinder Singh

    2018-06-01

    Full Text Available In this paper, attempts have been made on the detailed energy and exergy analysis of solar parabolic trough collectors (SPTCs driven combined power plant. The combination of supercritical CO2 (SCO2 cycle and organic Rankine cycle (ORC integrated with SPTCs has been used to produce power, in which SCO2 cycle and ORC are arranged as a topping and bottoming cycle. Five organic working fluids like R134a, R1234yf, R407c, R1234ze, and R245fa were selected for a low temperature bottoming ORC. Five key exergetic parameters such as exergetic efficiency, exergy destruction rate, fuel depletion ratio, irreversibility ratio, and improvement potential were also examined. It was revealed that exergetic and thermal efficiency of all the combined cycles enhances as the direct normal irradiance increases from 0.5 kW/m2 to 0.95 kW/m2. As can be seen, R407c combined cycle has the maximum exergetic as well as thermal efficiency which is around 78.07% at 0.95 kW/m2 and 43.49% at 0.95 kW/m2, respectively. Alternatively, the R134a and R245fa combined cycle yields less promising results with the marginal difference in their performance. As inferred from the study that SCO2 turbine and evaporator has a certain amount of exergy destruction which is around 9.72% and 8.54% of the inlet exergy, and almost 38.10% of the total exergy destruction in case of R407c combined cycle. Moreover, the maximum amount of exergy destructed by the solar collector field which is more than 25% of the solar inlet exergy and around 54% of the total destructed exergy. Finally, this study concludes that R407c combined cycle has a minimum fuel depletion ratio of 0.2583 for a solar collector and possess the highest power output of 3740 kW. Keywords: Supercritical CO2cycle, Organic Rankine cycle, Exergetic performance, SPTCs, Organic fluids

  6. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    Science.gov (United States)

    Al-Sulaiman, Fahad A.; Dincer, Ibrahim; Hamdullahpur, Feridun

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500 kW. The study reveals that there is 3-25% gain on exergy efficiency when trigeneration is used compared with the power cycle only. Also, the study shows that as the current density of the SOFC increases, the exergy efficiencies of power cycle, cooling cogeneration, heating cogeneration and trigeneration decreases. In addition, it was shown that the effect of changing the turbine inlet pressure and ORC pump inlet temperature are insignificant on the exergy efficiencies of the power cycle, cooling cogeneration, heating cogeneration and trigeneration. Also, the study reveals that the significant sources of exergy destruction are the ORC evaporator, air heat exchanger at the SOFC inlet and heating process heat exchanger.

  7. A combination of Stirling engine and high-efficiency boiler. Microsize cogeneration unit for heat and power supply; Stirlingmotor und Brennwertkessel vereint. Mikro-Waermekraftkopplung liefert Strom und Waerme

    Energy Technology Data Exchange (ETDEWEB)

    Donnerbauer, R.

    2001-03-01

    Apart from the heat pump and fuel cell, there is another new development: At the ISH in March, the Dutch producer EnAtEc intends to present a microsize cogeneration unit consisting of a gas-fuelled high-efficiency boiler and a free-piston Stirling motor. [German] Sind die Wirkungsgrade in der Heiztechnik ausgenutzt? Auf die Frage 'Was kommt nach der Brennwerttechnik?' gibt es jetzt neben Waermepumpe und Brennstoffzelle eine neue Antwort. Zur kommenden ISH Ende Maerz hat die niederlaendische Firma EnAtEc die Vorstellung einer 'Mikro-Waermekraftkopplung' ({mu}WK) angekuendigt. Das Geraet kombiniert einen Gas-Brennwertkessel mit einer Freikolben-Stirlingmaschine. (orig.)

  8. GTHTR300 cost reduction through design upgrade and cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Xing L., E-mail: yan.xing@jaea.go.jp; Sato, Hiroyuki; Kamiji, Yu; Imai, Yoshiyuki; Terada, Atsuhiko; Tachibana, Yukio; Kunitomi, Kazuhiko

    2016-09-15

    Japan Atomic Energy Agency began design and development of the Gas Turbine High Temperature Reactor of 300MWe nominal output (GTHTR300) in 2001. The reactor baseline design completed three years later was based on 850 °C core outlet temperature and a direct cycle gas turbine balance of plant. It attained 45.6% net power generation efficiency and 3.5 US¢/kW h cost of electricity. The cost was estimated 20% lower than LWR. The latest design upgrade has incorporated several major technological advances made in the past ten years to both reactor and balance of plant. As described in this paper, these advances have enabled raising the design basis reactor core outlet temperature to 950 °C and increasing power generating efficiency by nearly 5% point. Further implementation of seawater desalination cogeneration is made through employing a newly-proposed multi-stage flash process. Through efficient waste heat recovery of the reactor gas turbine power conversion cycle, a large cost credit is obtained against the conventionally produced water prices. Together, the design upgrade and the cogeneration are shown to reduce the GTHTR300 cost of electricity to under 2.7 US¢/kW h.

  9. GTHTR300 cost reduction through design upgrade and cogeneration

    International Nuclear Information System (INIS)

    Yan, Xing L.; Sato, Hiroyuki; Kamiji, Yu; Imai, Yoshiyuki; Terada, Atsuhiko; Tachibana, Yukio; Kunitomi, Kazuhiko

    2014-01-01

    Japan Atomic Energy Agency began design and development of the Gas Turbine High Temperature Reactor of 300MWe nominal output (GTHTR300) in 2001. The reactor baseline design completed three years later was based on 850°C core outlet temperature and a direct cycle gas turbine balance of plant. It attained 45.6% net power generation efficiency and 3.5US¢/KWh cost of electricity. The cost was estimated 20% lower than LWR. The latest design upgrade has incorporated several major technological advances made in the past ten years to both reactor and balance of plant. As described in this paper, these advances have enabled raising the design basis reactor core outlet temperature to 950°C and increasing power generating efficiency by nearly 5% point. Further implementation of seawater desalination cogeneration is made through employing a newly-proposed multi-stage flash process. Through efficient waste heat recovery of the reactor gas turbine power conversion cycle, a large cost credit is obtained against the conventionally produced water prices. Together, the design upgrade and the cogeneration are shown to reduce the GTHTR300 cost of electricity to under 2.7 US¢/KWh. (author)

  10. Combined heat and power generation with exhaust-heated two-stage absorption refrigerator. Performance of a pilot installation with a refrigeration capacity of 350 kW; Kraft-Waerme-Kaelte-Kopplung mit Abgas-Beheizter zweistufiger Absorptionskaeltemaschine. Betriebserfahrungen einer Pilotinstallation mit 350 kW Kaelteleistung

    Energy Technology Data Exchange (ETDEWEB)

    Plura, S.; Baumeister, D.; Koeberle, T.; Radspieler, M.; Schweigler, C. [Bayerisches Zentrum fuer Angewandte Energieforschung e.V. (ZAE Bayern), Garching (Germany)

    2007-07-01

    A new system concept for higher efficiency of cogeneration systems is developed in which a cogeneration unit is combined with a two-stage absorption refrigerator, and the waste heat of the cogeneration unit is directly passed on into the regenerator of the absorption refrigerator. The higher temperature level of the waste heat makes it possible to use a two-stage absorption cycle for higher energy efficiency. For simultaneous utilisation of low-temperature heat, the two-stage cycle is combined with a one-stage cycle for additional heat supply at a lower temperature level so that the exhaust of a typical cogeneration unit will be cooled to about 120 degC. At the same time, further waste heat of the cogeneration unit will be transferred to the heat pump via a hot water circuit. This concept with a combined single-stage and two-stage absorption circuit is referred to as a double-effect/single-effect circuit. The new system is used for energy supply in a spa, where the two-stage absorption refrigerator cools the water used for swimming pool cleaning with a refrigerating capacity of 350 kW and provides low-temperature heat for swimming pool heating with a capacity of 700 kW. (orig.)

  11. CANDU co-generation opportunities

    International Nuclear Information System (INIS)

    Meneley, D.A.; Duffey, R.B.; Pendergast, D.R.

    2000-01-01

    Modern technology makes use of natural energy 'wealth' (uranium) to produce useful energy 'currency' (electricity) that can be used to society's benefit. This energy currency can be further applied to help solve a difficult problem faced by mankind. Within the next few years we must reduce our use of the same fuels which have made many countries wealthy - fossil fuels. Fortunately, electricity can be called upon to produce another currency, namely hydrogen, which has some distinct advantages. Unlike electricity, hydrogen can be stored and can be recovered for later use as fuel. It also is extremely useful in chemical processes and refining. To achieve the objective of reducing greenhouse gas emissions hydrogen must, of course, be produced using a method which does not emit such gases. This paper summarizes four larger studies carried out in Canada in the past few years. From these results we conclude that there are several significant opportunities to use nuclear fission for various co-generation technologies that can lead to more appropriate use of energy resources and to reduced emissions. (author)

  12. Efficient production of electricity and water in cogeneration systems. [Desalination plant

    Energy Technology Data Exchange (ETDEWEB)

    Tadros, S.K.

    1981-11-01

    This paper discusses two topping cycle steam turbine cogeneration systems. The water desalination plant selected is the multistage flash evaporator cycle which uses brine recirculation and high temperature additives for scale protection and 233F maximum brine temperature. The paper mentions briefly the impact of future fuel prices on design and factors which would further improve thermal efficiency. The fuel chargeable to power is determined. 6 refs.

  13. A novel evaluation of heat-electricity cost allocation in cogenerations based on entropy change method

    International Nuclear Information System (INIS)

    Ye, Xuemin; Li, Chunxi

    2013-01-01

    As one of the most significant measures to improve energy utilization efficiency and save energy, cogeneration or combined heat and power (CHP) has been widely applied and promoted with positive motivations in many countries. A rational cost allocation model should indicate the performance of cogenerations and balance the benefits between electricity generation and heat production. Based on the second law of thermodynamics, the present paper proposes an entropy change method for cost allocation by choosing exhaust steam entropy as a datum point, and the new model works in conjunction with entropy change and irreversibility during energy conversion processes. The allocation ratios of heat cost with the present and existing methods are compared for different types of cogenerations. Results show that the allocation ratios with the entropy change method are more rational and the cost allocation model can make up some limitations involved in other approaches. The future energy policies and innovational directions for cogenerations and heat consumers should be developed. - Highlights: • A rational model of cogeneration cost allocation is established. • Entropy change method integrates the relation of entropy change and exergy losses. • The unity of measuring energy quality and quantity is materialized. • The benefits between electricity generation and heat production are balanced

  14. The impact of small scale cogeneration on the gas demand at distribution level

    International Nuclear Information System (INIS)

    Vandewalle, J.; D’haeseleer, W.

    2014-01-01

    Highlights: • Impact on the gas network of a massive implementation of cogeneration. • Distributed energy resources in a smart grid environment. • Optimisation of cogeneration scheduling. - Abstract: Smart grids are often regarded as an important step towards the future energy system. Combined heat and power (CHP) or cogeneration has several advantages in the context of the smart grid, which include the efficient use of primary energy and the reduction of electrical losses through transmission. However, the role of the gas network is often overlooked in this context. Therefore, this work presents an analysis of the impact of a massive implementation of small scale (micro) cogeneration units on the gas demand at distribution level. This work shows that using generic information in the simulations overestimates the impact of CHP. Furthermore, the importance of the thermal storage tank capacity on the impact on the gas demand is shown. Larger storage tanks lead to lower gas demand peaks and hence a lower impact on the gas distribution network. It is also shown that the use of an economically led controller leads to similar results compared to classical heat led control. Finally, it results that a low sell back tariff for electricity increases the impact of cogeneration on the gas demand peak

  15. Co-Generation and Renewables: Solutions for a Low-Carbon Energy Future

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Co-generation and renewables: solutions for a low-carbon energy future shows that powerful synergies exist when co-generation and renewables work together. The report documents, for the first time, some of the little-known complementary aspects of the two technologies. It also re-emphasises the stand-alone benefits of each technology. Thus, decision makers can use the report as a 'one-stop shop' when they need credible information on co-generation, renewables and the possible synergies between the two. It also provides answers to policy makers' questions about the potential energy and environmental benefits of an increased policy commitment to both co-generation and renewables. Secure, reliable, affordable and clean energy supplies are fundamental to economic and social stability and development. Energy and environmental decision-makers are faced with major challenges that require action now in order to ensure a more sustainable future. More efficient use of, and cleaner primary energy sources can help to achieve this goal. Co-generation -- also known as combined heat and power (CHP) -- represents a proven, cost-effective and energy-efficient solution for delivering electricity and heat. Renewable sources provide clean and secure fuels for producing electricity and heat.

  16. Theoretical analysis of a combined power and ejector refrigeration cycle using zeotropic mixture

    International Nuclear Information System (INIS)

    Yang, Xingyang; Zhao, Li; Li, Hailong; Yu, Zhixin

    2015-01-01

    Highlights: • A combined power and refrigeration cycle using zeotropic mixture is analyzed. • The cycle performances with different mixture compositions are compared. • Both exergy and parametric analysis of the combined cycle are conducted. - Abstract: A theoretical study on a combined power and ejector refrigeration cycle using zeotropic mixture isobutane/pentane is carried out. The performances of different mixture compositions are compared. An exergy analysis is conducted for the cycle. The result reveals that most exergy destruction happens in the ejector, where more than 40% exergy is lost. The heat exchange in generator causes the second largest exergy loss, larger than 28%. As the mass fraction of isobutane changes ranges from 100% to 0%, the relative exergy destruction of each component is also changing. And mixture isobutane/pentane (50/50) has the maximum exergy efficiency of 7.83%. The parametric analysis of generator temperature, condenser temperature and evaporator temperature for all the mixtures shows that, all these three thermodynamic parameters have a strong effect on the cycle performance.

  17. Modeling and simulation of syngas purification and power generation in integrated gasification combined cycle (IGCS)

    Energy Technology Data Exchange (ETDEWEB)

    Mehmood, N; Zaman, Z U; Mehran, M T [National Development, Islamabad (Pakistan)

    2011-07-01

    Integrated Gasification Combined Cycle (IGCC) is one of the most promising technologies for power generation; The environmental benefits and the higher energy conversion efficiency distinguish it from traditional coal generation technologies. This work presents a structured and validated conceptual model of purification of coal gas produced during the Underground Coal Gasification (UCG) of coal containing high sulfur contents. Gas cleaning operations for CO/sub 2/, H/sub 2/S and moisture removal have been modeled in steady and dynamic state. The power generation from combined cycle is also modeled. The model has been developed using Aspen HYSYS and Aspen Plus simulation software. Predicted results of clean gas composition and generated power present a good agreement with industrial data and efficiency parameters. This study is aimed at obtaining optimal assessment of an integrated gasification combined cycle (IGCC) power plant configurations. (author)

  18. Modeling and simulation of syngas purification and power generation in integrated gasification combined cycle (IGCS)

    International Nuclear Information System (INIS)

    Mehmood, N.; Zaman, Z.U.; Mehran, M.T.

    2011-01-01

    Integrated Gasification Combined Cycle (IGCC) is one of the most promising technologies for power generation; The environmental benefits and the higher energy conversion efficiency distinguish it from traditional coal generation technologies. This work presents a structured and validated conceptual model of purification of coal gas produced during the Underground Coal Gasification (UCG) of coal containing high sulfur contents. Gas cleaning operations for CO/sub 2/, H/sub 2/S and moisture removal have been modeled in steady and dynamic state. The power generation from combined cycle is also modeled. The model has been developed using Aspen HYSYS and Aspen Plus simulation software. Predicted results of clean gas composition and generated power present a good agreement with industrial data and efficiency parameters. This study is aimed at obtaining optimal assessment of an integrated gasification combined cycle (IGCC) power plant configurations. (author)

  19. Minimization of the LCA impact of thermodynamic cycles using a combined simulation-optimization approach

    International Nuclear Information System (INIS)

    Brunet, Robert; Cortés, Daniel; Guillén-Gosálbez, Gonzalo; Jiménez, Laureano; Boer, Dieter

    2012-01-01

    This work presents a computational approach for the simultaneous minimization of the total cost and environmental impact of thermodynamic cycles. Our method combines process simulation, multi-objective optimization and life cycle assessment (LCA) within a unified framework that identifies in a systematic manner optimal design and operating conditions according to several economic and LCA impacts. Our approach takes advantages of the complementary strengths of process simulation (in which mass, energy balances and thermodynamic calculations are implemented in an easy manner) and rigorous deterministic optimization tools. We demonstrate the capabilities of this strategy by means of two case studies in which we address the design of a 10 MW Rankine cycle modeled in Aspen Hysys, and a 90 kW ammonia-water absorption cooling cycle implemented in Aspen Plus. Numerical results show that it is possible to achieve environmental and cost savings using our rigorous approach. - Highlights: ► Novel framework for the optimal design of thermdoynamic cycles. ► Combined use of simulation and optimization tools. ► Optimal design and operating conditions according to several economic and LCA impacts. ► Design of a 10MW Rankine cycle in Aspen Hysys, and a 90kW absorption cycle in Aspen Plus.

  20. Minimization of the LCA impact of thermodynamic cycles using a combined simulation-optimization approach

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, Robert; Cortes, Daniel [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Guillen-Gosalbez, Gonzalo [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Jimenez, Laureano [Departament d' Enginyeria Quimica, Escola Tecnica Superior d' Enginyeria Quimica, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007 Tarragona (Spain); Boer, Dieter [Departament d' Enginyeria Mecanica, Escola Tecnica Superior d' Enginyeria, Universitat Rovira i Virgili, Campus Sescelades, Avinguda Paisos Catalans 26, 43007, Tarragona (Spain)

    2012-12-15

    This work presents a computational approach for the simultaneous minimization of the total cost and environmental impact of thermodynamic cycles. Our method combines process simulation, multi-objective optimization and life cycle assessment (LCA) within a unified framework that identifies in a systematic manner optimal design and operating conditions according to several economic and LCA impacts. Our approach takes advantages of the complementary strengths of process simulation (in which mass, energy balances and thermodynamic calculations are implemented in an easy manner) and rigorous deterministic optimization tools. We demonstrate the capabilities of this strategy by means of two case studies in which we address the design of a 10 MW Rankine cycle modeled in Aspen Hysys, and a 90 kW ammonia-water absorption cooling cycle implemented in Aspen Plus. Numerical results show that it is possible to achieve environmental and cost savings using our rigorous approach. - Highlights: Black-Right-Pointing-Pointer Novel framework for the optimal design of thermdoynamic cycles. Black-Right-Pointing-Pointer Combined use of simulation and optimization tools. Black-Right-Pointing-Pointer Optimal design and operating conditions according to several economic and LCA impacts. Black-Right-Pointing-Pointer Design of a 10MW Rankine cycle in Aspen Hysys, and a 90kW absorption cycle in Aspen Plus.

  1. Combined Turbine and Cycle Optimization for Organic Rankine Cycle Power Systems—Part B: Application on a Case Study

    Directory of Open Access Journals (Sweden)

    Angelo La Seta

    2016-05-01

    Full Text Available Organic Rankine cycle (ORC power systems have recently emerged as promising solutions for waste heat recovery in low- and medium-size power plants. Their performance and economic feasibility strongly depend on the expander. The design process and efficiency estimation are particularly challenging due to the peculiar physical properties of the working fluid and the gas-dynamic phenomena occurring in the machine. Unlike steam Rankine and Brayton engines, organic Rankine cycle expanders combine small enthalpy drops with large expansion ratios. These features yield turbine designs with few highly-loaded stages in supersonic flow regimes. Part A of this two-part paper has presented the implementation and validation of the simulation tool TURAX, which provides the optimal preliminary design of single-stage axial-flow turbines. The authors have also presented a sensitivity analysis on the decision variables affecting the turbine design. Part B of this two-part paper presents the first application of a design method where the thermodynamic cycle optimization is combined with calculations of the maximum expander performance using the mean-line design tool described in part A. The high computational cost of the turbine optimization is tackled by building a model which gives the optimal preliminary design of an axial-flow turbine as a function of the cycle conditions. This allows for estimating the optimal expander performance for each operating condition of interest. The test case is the preliminary design of an organic Rankine cycle turbogenerator to increase the overall energy efficiency of an offshore platform. For an increase in expander pressure ratio from 10 to 35, the results indicate up to 10% point reduction in expander performance. This corresponds to a relative reduction in net power output of 8.3% compared to the case when the turbine efficiency is assumed to be 80%. This work also demonstrates that this approach can support the plant designer

  2. A combined power cycle utilizing low-temperature waste heat and LNG cold energy

    International Nuclear Information System (INIS)

    Shi Xiaojun; Che Defu

    2009-01-01

    This paper has proposed a combined power system, in which low-temperature waste heat can be efficiently recovered and cold energy of liquefied natural gas (LNG) can be fully utilized as well. This system consists of an ammonia-water mixture Rankine cycle and an LNG power generation cycle, and it is modelled by considering mass, energy and species balances for every component and thermodynamic analyses are conducted. The results show that the proposed combined cycle has good performance, with net electrical efficiency and exergy efficiency of 33% and 48%, respectively, for a typical operating condition. The power output is equal to 1.25 MWh per kg of ammonia-water mixture. About 0.2 MW of electrical power for operating sea water pumps can be saved. Parametric analyses are performed for the proposed combined cycle to evaluate the effects of key factors on the performance of the proposed combined cycle through simulation calculations. Results show that a maximum net electrical efficiency can be obtained as the inlet pressure of ammonia turbine increases and the peak value increases as the ammonia mass fraction increases. Exergy efficiency goes up with the increased ammonia turbine inlet pressure. With the ammonia mass fraction increases, the net electrical efficiency increases, whereas exergy efficiency decreases. For increasing LNG turbine inlet pressure or heat source temperature, there is also a peak of net electrical efficiency and exergy efficiency. With the increase of LNG gas turbine outlet pressure, exergy efficiency increases while net electrical efficiency drops

  3. Study on economic potential of nuclear-gas combined cycle power generation in Chinese market

    International Nuclear Information System (INIS)

    Zhou Zhiwei; Bian Zhiqiang; Yang Mengjia

    2004-01-01

    Facing the challenges of separation of electric power plant and grid, and the deregulation of Chinese electricity supplying market in near future, nuclear power plants mainly operated as based load at the present regulated market should look for new operation mode. The economics of electric generation with nuclear-natural gas combined cycle is studied based on current conditions of natural gas and nuclear power plants in China. The results indicate that the technology development of nuclear-natural gas combined cycle for power generation is of potential prospects in Chinese electric market. (authors)

  4. Economic comparison of clean coal generating technologies with natural gas-combined cycle systems

    International Nuclear Information System (INIS)

    Sebesta, J.J.; Hoskins, W.W.

    1990-01-01

    This paper reports that there are four combustion technologies upon which U.S. electric utilities are expected to rely for the majority of their future power generating needs. These technologies are pulverized coal- fired combustion (PC); coal-fired fluidized bed combustion (AFBC); coal gasification, combined cycle systems (CGCC); and natural gas-fired combined cycle systems (NGCC). The engineering and economic parameters which affect the choice of a technology include capital costs, operating and maintenance costs, fuel costs, construction schedule, process risk, environmental and site impacts, fuel efficiency and flexibility, plant availability, capacity factors, timing of startup, and the importance of utility economic and financial factors

  5. Power and efficiency optimization for combined Brayton and inverse Brayton cycles

    International Nuclear Information System (INIS)

    Zhang Wanli; Chen Lingen; Sun Fengrui

    2009-01-01

    A thermodynamic model for open combined Brayton and inverse Brayton cycles is established considering the pressure drops of the working fluid along the flow processes and the size constraints of the real power plant using finite time thermodynamics in this paper. There are 11 flow resistances encountered by the gas stream for the combined Brayton and inverse Brayton cycles. Four of these, the friction through the blades and vanes of the compressors and the turbines, are related to the isentropic efficiencies. The remaining flow resistances are always present because of the changes in flow cross-section at the compressor inlet of the top cycle, combustion inlet and outlet, turbine outlet of the top cycle, turbine outlet of the bottom cycle, heat exchanger inlet, and compressor inlet of the bottom cycle. These resistances control the air flow rate and the net power output. The relative pressure drops associated with the flow through various cross-sectional areas are derived as functions of the compressor inlet relative pressure drop of the top cycle. The analytical formulae about the relations between power output, thermal conversion efficiency, and the compressor pressure ratio of the top cycle are derived with the 11 pressure drop losses in the intake, compression, combustion, expansion, and flow process in the piping, the heat transfer loss to the ambient, the irreversible compression and expansion losses in the compressors and the turbines, and the irreversible combustion loss in the combustion chamber. The performance of the model cycle is optimized by adjusting the compressor inlet pressure of the bottom cycle, the air mass flow rate and the distribution of pressure losses along the flow path. It is shown that the power output has a maximum with respect to the compressor inlet pressure of the bottom cycle, the air mass flow rate or any of the overall pressure drops, and the maximized power output has an additional maximum with respect to the compressor pressure

  6. Analysis of the effects of combining air separation with combustion in a zero emissions (ZEITMOP) cycle

    International Nuclear Information System (INIS)

    Foy, Kirsten; McGovern, Jim

    2007-01-01

    The ZEITMOP cycle is a zero emissions (oxyfuel) power plant cycle proposed by Evgeny Yantovski that uses oxygen ion transport membranes to extract the oxygen required for combustion from air. A current proposed configuration of the cycle requires an oxygen ion transport membrane air separation unit operating at 920 deg. C and a separate combustion chamber operating at 1400 deg. C. If oxygen is consumed by a chemical reaction on the permeate side of an oxygen transport membrane, the oxygen flux is larger, so the air separation unit can be physically smaller. In addition, if this reaction is exothermic, the air separation unit is heated by the reaction, requiring no additional heating. Combustion fulfils both of these requirements, so combustion in the oxygen transport membrane air separation unit would allow a smaller air separation unit, which would also act as a combustion chamber. Unfortunately, a combustion temperature of 1400 deg. C will damage most oxygen transport membranes available today. However, new materials are continually being developed and investigated, so it may be possible to have an oxygen transport membrane chamber operating at 1400 deg. C in the short to medium term future. Alternatively the combustion chamber may be cooled, allowing it to operate at more realistic temperatures for currently available oxygen transport membranes. Controlling the operation temperature of the combined unit requires changing the mass flow rates of various streams of fluid in the cycle. This will have an effect on the work and heat transfers in the cycle. It is possible to calculate the theoretical effects of these changes in temperature. This paper presents an analysis investigating the impact of combining the air separator and the combustion chamber. The efficiency of the cycle was calculated at various operation temperatures for the combined oxygen transport membrane combustion chamber. The results were compared to the efficiency of the current cycle. The changes

  7. Performance analysis and binary working fluid selection of combined flash-binary geothermal cycle

    International Nuclear Information System (INIS)

    Zeyghami, Mehdi

    2015-01-01

    Performance of the combined flash-binary geothermal power cycle for geofluid temperatures between 150 and 250 °C is studied. A thermodynamic model is developed, and the suitable binary working fluids for different geofluid temperatures are identified from a list of thirty working fluid candidates, consisting environmental friendly refrigerants and hydrocarbons. The overall system exergy destruction and Vapor Expansion Ratio across the binary cycle turbine are selected as key performance indicators. The results show that for low-temperature heat sources using refrigerants as binary working fluids result in higher overall cycle efficiency and for medium and high-temperature resources, hydrocarbons are more suitable. For combined flash-binary cycle, secondary working fluids; R-152a, Butane and Cis-butane show the best performances at geofluid temperatures 150, 200 and 250 °C respectively. The overall second law efficiency is calculated as high as 0.48, 0.55 and 0.58 for geofluid temperatures equal 150, 200 and 250 °C respectively. The flash separator pressure found to has important effects on cycle operation and performance. Separator pressure dictates the work production share of steam and binary parts of the system. And there is an optimal separator pressure at which overall exergy destruction of the cycle achieves its minimum value. - Highlights: • Performance of the combined flash-binary geothermal cycle is investigated. • Thirty different fluids are screened to find the most suitable ORC working fluid. • Optimum cycle operation conditions presented for geofluids between 150 °C and 250 °C. • Refrigerants are more suitable for the ORC at geothermal sources temperature ≤200 °C. • Hydrocarbons are more suitable for the ORC at geothermal sources temperature >200 °C

  8. Transient behaviour of small HTR for cogeneration

    International Nuclear Information System (INIS)

    Verkerk, E.C.; Van Heek, A.I.

    2000-01-01

    The Dutch market for combined generation of heat and power identifies a unit size of 40 MW thermal for the conceptual design of a nuclear cogeneration plant. The ACACIA system provides 14 MWe electricity combined with 17 t/h of high temperature steam (220 deg C, 10 bar) with a pebble-bed high temperature reactor directly coupled with a helium compressor and a helium turbine. The design of this small CHP unit that is used for industrial applications is mainly based on a pre-feasibility study in 1996, performed by a joint working group of five Dutch organisations, in which technical feasibility was shown. Thermal hydraulic and reactor physics analyses show favourable control characteristics during normal operation and a benign response to loss of helium coolant and loss of flow conditions. Throughout the response on these highly infrequent conditions, ample margin exists between the highest fuel temperatures and the temperature above which fuel degradation will occur. To come to quantitative statements about the ACACIA transient behaviour, a calculational coupling between the high temperature reactor core analysis code package PANTHER/DIREKT and the thermal hydraulic code RELAP5 for the energy conversion system has been made. This coupling offers a more realistic simulation of the entire system, since it removes the necessity of forcing boundary conditions on the simulation models at the data transfer points. In this paper, the models used for the dynamic components of the energy conversion system are described, and the results of the calculation for two operational transients in order to demonstrate the effects of the interaction between reactor core and its energy conversion system are shown. Several transient cases that are representative as operational transients for an HTR will be discussed, including one representing a load rejection case that shows the functioning of the control system, in particular the bypass valve. Another transient is a load following

  9. Thermodynamic assessment of impact of inlet air cooling techniques on gas turbine and combined cycle performance

    International Nuclear Information System (INIS)

    Mohapatra, Alok Ku; Sanjay

    2014-01-01

    The article is focused on the comparison of impact of two different methods of inlet air cooling (vapor compression and vapor absorption cooling) integrated to a cooled gas turbine based combined cycle plant. Air-film cooling has been adopted as the cooling technique for gas turbine blades. A parametric study of the effect of compressor pressure ratio, compressor inlet temperature (T i , C ), turbine inlet temperature (T i , T ), ambient relative humidity and ambient temperature on performance parameters of plant has been carried out. Optimum T i , T corresponding to maximum plant efficiency of combined cycle increases by 100 °C due to the integration of inlet air cooling. It has been observed that vapor compression cooling improves the efficiency of gas turbine cycle by 4.88% and work output by 14.77%. In case of vapor absorption cooling an improvement of 17.2% in gas cycle work output and 9.47% in gas cycle efficiency has been observed. For combined cycle configuration, however, vapor compression cooling should be preferred over absorption cooling in terms of higher plant performance. The optimum value of compressor inlet temperature has been observed to be 20 °C for the chosen set of conditions for both the inlet air cooling schemes. - Highlights: • Inlet air cooling improves performance of cooled gas turbine based combined cycle. • Vapor compression inlet air cooling is superior to vapor absorption inlet cooling. • For every turbine inlet temperature, there exists an optimum pressure ratio. • The optimum compressor inlet temperature is found to be 293 K

  10. Cogeneration plant noise: Environmental impacts and abatement

    International Nuclear Information System (INIS)

    De Renzio, M.; Ciocca, B.

    1991-01-01

    In Italy, ever increasing attention to environmental problems has led to legislation requiring cogeneration plant owners to perform environmental impact assessments in order to determine plant conformity with pollution laws. This paper, based on an in-depth analysis of physics fundamentals relevant to the nature and effects of noise, examines the principal sources of noise in industrial cogeneration plants and the intensity and range of the effects of this noise on the local environment. A review is then made of the different methods of noise pollution abatement (e.g., heat and corrosion resistant silencers for gas turbines, varying types and thicknesses of acoustic insulation placed in specific locations) that can be effectively applied to cogeneration plant equipment and housing

  11. Cogeneration plants: SNAM (Italy) initiatives and incentives

    International Nuclear Information System (INIS)

    Pipparelli, M.

    1991-01-01

    First, an overall picture is presented of the extension of the use of cogeneration by the Italian brick industry. The particular suitability and usefulness of this form of energy to the brick industry are pointed out. Then a look is given at the legal and financial incentives which have been built into the National Energy Plan to encourage on-site production by Italian industries. Finally, a review is made of initiatives made by SNAM (the Italian National Methane Distribution Society) to develop a favourable tariff structure for on-site power producers using methane as their energy source, as well as, of the Society's efforts to set up a cogeneration equipment consulting service which would provide advice on cogeneration plant design, operation and maintenance

  12. Upscaling a district heating system based on biogas cogeneration and heat pumps

    NARCIS (Netherlands)

    van Leeuwen, Richard Pieter; Fink, J.; Smit, Gerardus Johannes Maria; de Wit, Jan B.

    2015-01-01

    The energy supply of the Meppel district Nieuwveense landen is based on biogas cogeneration, district heating, and ground source heat pumps. A centrally located combined heat and power engine (CHP) converts biogas from the municipal wastewater treatment facility into electricity for heat pumps and

  13. A Combined High and Low Cycle Fatigue Model for Life Prediction of Turbine Blades

    Directory of Open Access Journals (Sweden)

    Shun-Peng Zhu

    2017-06-01

    Full Text Available Combined high and low cycle fatigue (CCF generally induces the failure of aircraft gas turbine attachments. Based on the aero-engine load spectrum, accurate assessment of fatigue damage due to the interaction of high cycle fatigue (HCF resulting from high frequency vibrations and low cycle fatigue (LCF from ground-air-ground engine cycles is of critical importance for ensuring structural integrity of engine components, like turbine blades. In this paper, the influence of combined damage accumulation on the expected CCF life are investigated for turbine blades. The CCF behavior of a turbine blade is usually studied by testing with four load-controlled parameters, including high cycle stress amplitude and frequency, and low cycle stress amplitude and frequency. According to this, a new damage accumulation model is proposed based on Miner’s rule to consider the coupled damage due to HCF-LCF interaction by introducing the four load parameters. Five experimental datasets of turbine blade alloys and turbine blades were introduced for model validation and comparison between the proposed Miner, Manson-Halford, and Trufyakov-Kovalchuk models. Results show that the proposed model provides more accurate predictions than others with lower mean and standard deviation values of model prediction errors.

  14. Cogeneration plants in Italy: Licensing aspects

    International Nuclear Information System (INIS)

    Buscaglione, A.

    1991-01-01

    This paper focusses on administrative/bureaucratic problems relative to the licensing of cogeneration plants in Italy. The current stumbling block appears to lie in organizational difficulties relative to the coordination of various Government authorized safety committees responsible for the drafting up of suitable legislation governing cogeneration plant fire safety aspects. The author cites the possible environmental benefits in terms of air pollution abatement that could have been had with the timely start-up of a new 7 MW plant (in Lombardia) still awaiting its go-ahead authorization

  15. Potable water cogeneration using nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, G. [Instituto Nacional de Investigaciones Nucleares, Estado de Mexico (Mexico); Instituto Politecnico Nacional, Escuela Superior de Fisica y Matematicas, D.F. (Mexico); Ramirez, J.R. [Instituto Nacional de Investigaciones Nucleares, Estado de Mexico (Mexico); Valle, E. del [Instituto Politecnico Nacional, Escuela Superior de Fisica y Matematicas, D.F. (Mexico)

    2014-07-01

    Mexico is a country with a diversity of conditions; the Peninsula of Baja California is a semi-arid region with a demand of potable water and electricity where small nuclear power can be used. This part of the country has a low density population, a high pressure over the water resources in the region, and their needs of electricity are small. The SMART reactor will be assessed as co-generator for this region; where five different scenarios of cogeneration of electricity and potable water production are considered, the levelized cost of electricity and potable water are obtained to assess their competitiveness. (author)

  16. Thermal-economic analysis of cogeneration systems

    International Nuclear Information System (INIS)

    Walter, A.C.S.; Bajay, S.V.

    1992-01-01

    Approximately 80 countries produce sugar, and fortuitously alcohol, from sugar cane. In all these countries the cogeneration technology of steam turbines is utilized, although almost always inefficient. The greater potential of cogeneration in Brazil is in sugar and alcohol sector, because of the use of sugar cane bagasse as combustible. This work applies the techniques of simulation and economic analysis to different configuration of plants, to determine power generation and associated costs of each alternative. The application of the same procedure at operating condition of several configurations in transient system permits the determination of production profile of exceeding during one day. (C.M.)

  17. An update technology for integrated biomass gasification combined cycle power plant

    International Nuclear Information System (INIS)

    Bhattacharya, P.; Dey, S.

    2014-01-01

    A discussion is presented on the technical analysis of a 6.4 M W_e integrated biomass gasification combined cycle (IBGCC) plant. It features three numbers of downdraft biomass gasifier systems with suitable gas clean-up trains, three numbers of internal combustion (IC) producer gas engines for producing 5.85 MW electrical power in open cycle and 550 kW power in a bottoming cycle using waste heat. Comparing with IC gas engine single cycle systems, this technology route increases overall system efficiency of the power plant, which in turn improves plant economics. Estimated generation cost of electricity indicates that mega-watt scale IBGCC power plants can contribute to good economies of scale in India. This paper also highlight's the possibility of activated carbon generation from the char, a byproduct of gasification process, and use of engine's jacket water heat to generate chilled water through VAM for gas conditioning. (author)

  18. Optimum operating conditions for a combined power and cooling thermodynamic cycle

    International Nuclear Information System (INIS)

    Sadrameli, S.M.; Goswami, D.Y.

    2007-01-01

    The combined production of thermal power and cooling with an ammonia-water based cycle proposed by Goswami is under intensive investigation. In the cycle under consideration, simultaneous cooling output is produced by expanding an ammonia-rich vapor in an expander to sub-ambient temperatures and subsequently heating the cool exhaust. When this mechanism for cooling production is considered in detail, it is apparent that the cooling comes at some expense to work production. To optimize this trade-off, a very specific coefficient-of-performance has been defined. In this paper, the simulation of the cycle was carried out in the process simulator ASPEN Plus. The optimum operating conditions have been found by using the Equation Oriented mode of the simulator and some of the results have been compared with the experimental data obtained from the cycle. The agreement between the two sets proves the accuracy of the optimization results

  19. Combined cycle solar central receiver hybrid power system study. Volume III. Appendices. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    A design study for a 100 MW gas turbine/steam turbine combined cycle solar/fossil-fuel hybrid power plant is presented. This volume contains the appendices: (a) preconceptual design data; (b) market potential analysis methodology; (c) parametric analysis methodology; (d) EPGS systems description; (e) commercial-scale solar hybrid power system assessment; and (f) conceptual design data lists. (WHK)

  20. Off-design performance of a chemical looping combustion (CLC) combined cycle: effects of ambient temperature

    Science.gov (United States)

    Chi, Jinling; Wang, Bo; Zhang, Shijie; Xiao, Yunhan

    2010-02-01

    The present work investigates the influence of ambient temperature on the steady-state off-design thermodynamic performance of a chemical looping combustion (CLC) combined cycle. A sensitivity analysis of the CLC reactor system was conducted, which shows that the parameters that influence the temperatures of the CLC reactors most are the flow rate and temperature of air entering the air reactor. For the ambient temperature variation, three off-design control strategies have been assumed and compared: 1) without any Inlet Guide Vane (IGV) control, 2) IGV control to maintain air reactor temperature and 3) IGV control to maintain constant fuel reactor temperature, aside from fuel flow rate adjusting. Results indicate that, compared with the conventional combined cycle, due to the requirement of pressure balance at outlet of the two CLC reactors, CLC combined cycle shows completely different off-design thermodynamic characteristics regardless of the control strategy adopted. For the first control strategy, temperatures of the two CLC reactors both rise obviously as ambient temperature increases. IGV control adopted by the second and the third strategy has the effect to maintain one of the two reactors' temperatures at design condition when ambient temperature is above design point. Compare with the second strategy, the third would induce more severe decrease of efficiency and output power of the CLC combined cycle.

  1. Combined Heat and Power: Coal-Fired Air Turbine (CAT)-Cycle Plant

    International Nuclear Information System (INIS)

    Lee Recca

    1999-01-01

    By combining an integrated system with a gas turbine, coal-fired air turbine cycle technology can produce energy at an efficiency rate of over 40%, with capital and operating costs below those of competing conventional systems. Read this fact sheet to discover the additional benefits of this exciting new technology

  2. COMBINED CYCLE GAS TURBINE FOR THERMAL POWER STATIONS: EXPERIENCE IN DESIGNING AND OPERATION, PROSPECTS IN APPLICATION

    Directory of Open Access Journals (Sweden)

    N. V. Karnitsky

    2014-01-01

    Full Text Available The paper has reviewed main world tendencies in power consumption and power system structure. Main schemes of combined cycle gas turbines have been considered in the paper. The paper contains an operational analysis of CCGT blocks that are operating within the Belarusian energy system. The analysis results have been given in tables showing main operational indices of power blocks

  3. Evaluation of Indirect Combined Cycle in Very High Temperature Gas--Cooled Reactor

    International Nuclear Information System (INIS)

    Chang Oh; Robert Barner; Cliff Davis; Steven Sherman; Paul Pickard

    2006-01-01

    The U.S. Department of Energy and Idaho National Laboratory are developing a very high temperature reactor to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is twofold: (a) efficient, low-cost energy generation and (b) hydrogen production. Although a next-generation plant could be developed as a single-purpose facility, early designs are expected to be dual purpose, as assumed here. A dual-purpose design with a combined cycle of a Brayton top cycle and a bottom Rankine cycle was investigated. An intermediate heat transport loop for transporting heat to a hydrogen production plant was used. Helium, CO2, and a helium-nitrogen mixture were studied to determine the best working fluid in terms of the cycle efficiency. The relative component sizes were estimated for the different working fluids to provide an indication of the relative capital costs. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the cycle were performed to determine the effects of varying conditions in the cycle. This gives some insight into the sensitivity of the cycle to various operating conditions as well as trade-offs between efficiency and component size. Parametric studies were carried out on reactor outlet temperature, mass flow, pressure, and turbine cooling

  4. Experimental analysis of micro-cogeneration units based on reciprocating internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Possidente, R.; Sibilio, S. [Seconda Universita di Napoli, Dipartimento di Storia e Processi dell' ambiente Antropizzato (DiSPAMA), Borgo San Lorenzo, Aversa, CE (Italy); Roselli, C.; Sasso, M. [Dipartimento di Ingegneria, Universita degli Studi del Sannio, Benevento (Italy)

    2006-07-01

    The cogeneration, or the combined production of electric and/or mechanical and thermal energy, is a well-established technology now, which has important environmental benefits and has been noted by the European Community as one of the first elements to save primary energy, to avoid network losses and to reduce the greenhouse gas emissions. In particular, our interest will be focused on the micro-cogeneration, MCHP (electric power up to 15 kW), which represents a valid and interesting application of this technology which refers, above all, to residential and light commercial users [M. Dentice d'Accadia, M. Sasso, S. Sibilio, Cogeneration for energy saving in household applications, in: P. Bertoldi, A. Ricci, A. de Almeida (Eds.), Energy Efficiency in Household Appliances and Lighting, Springer, Berlin, 2001, pp. 210-221; Directive 2004/8/EC of the European Parliament and of the Council of the 11 February 2004 on the promotion of cogeneration based on the useful heat demand in the internal energy market and amending Directive 92/42/EEC, Official Journal of the European Union (2004)]. In particular, our work group started a R and D programme on micro-cogeneration in 1995: a laboratory, equipped with the most common appliances (washing-machine, dishwasher, storage water heater, ...), has been built and some MCHP prototypes have been tested too. In this article, the results of an intense experimental activity on three different micro-cogenerators, one of them made in Japan and in a pre-selling phase, are reported. In a previous paper a detailed analysis of the test facility, with the description of the equipment and the data acquisition systems, can be found [M. Dentice d'Accadia, M. Sasso, S. Sibilio, R. Vanoli, Micro-combined heat and power in residential and light commercial applications, Applied Thermal Engineering 23 (2003) 1247-1259]. A typical 3-E (Energetic, Economic and Environmental) approach has been performed to compare the proposed energy system

  5. Thermodynamic Analyses of Biomass Gasification Integrated Externally Fired, Post-Firing and Dual-Fuel Combined Cycles

    Directory of Open Access Journals (Sweden)

    Saeed Soltani

    2015-01-01

    Full Text Available In the present work, the results are reported of the energy and exergy analyses of three biomass-related processes for electricity generation: the biomass gasification integrated externally fired combined cycle, the biomass gasification integrated dual-fuel combined cycle, and the biomass gasification integrated post-firing combined cycle. The energy efficiency for the biomass gasification integrated post-firing combined cycle is 3% to 6% points higher than for the other cycles. Although the efficiency of the externally fired biomass combined cycle is the lowest, it has an advantage in that it only uses biomass. The energy and exergy efficiencies are maximized for the three configurations at particular values of compressor pressure ratios, and increase with gas turbine inlet temperature. As pressure ratio increases, the mass of air per mass of steam decreases for the biomass gasification integrated post-firing combined cycle, but the pressure ratio has little influence on the ratio of mass of air per mass of steam for the other cycles. The gas turbine exergy efficiency is the highest for the three configurations. The combustion chamber for the dual-fuel cycle exhibits the highest exergy efficiency and that for the post-firing cycle the lowest. Another benefit of the biomass gasification integrated externally fired combined cycle is that it exhibits the highest air preheater and heat recovery steam generator exergy efficiencies.

  6. Evolution of near term PBMR steam and cogeneration applications - HTR2008-58219

    International Nuclear Information System (INIS)

    Kuhr, R. W.; Hannink, R.; Paul, K.; Kriel, W.; Greyvenstein, R.; Young, R.

    2008-01-01

    US and international applications for large onsite cogeneration (steam and power) systems are emerging as a near term market for the PBMR. The South African PBMR demonstration project applies a high temperature (900 deg. C) Brayton cycle for high efficiency power generation. In addition, a number of new applications are being investigated using an intermediate temperature range (700-750 deg. C) with a simplified heat supply system design. This intermediate helium delivery temperature supports conventional steam Rankine cycle designs at higher efficiencies than obtained from water type reactor systems. These designs can be adapted for cogeneration of steam, similar to the design of gas turbine cogeneration plants that supply steam and power at many industrial sites. This temperature range allows use of conventional or readily qualifiable materials and equipment, avoiding some cost premiums associated with more difficult operating conditions. As gas prices and CO 2 values increase, the potential value of a small nuclear reactor with advanced safety characteristics increases dramatically. Because of its smaller scale, the 400-500 MWt PBMR offers the economic advantages of onsite thermal integration (steam, hot water and desalination co-production) and of providing onsite power at cost versus at retail industrial rates avoiding transmission and distribution costs. Advanced safety characteristics of the PBMR support the location of plants adjacent to steam users, district energy systems, desalination plants, and other large commercial and industrial facilities. Additional benefits include price stability, long term security of energy supply and substantial CO 2 reductions. Target markets include existing sites using gas fired boilers and cogeneration units, new projects such as refinery and petrochemical expansions, and coal-to-liquids projects where steam and power represent major burdens on fuel use and CO 2 emissions. Lead times associated with the nuclear licensing

  7. Low temperature heat from natural gas. Life cycle analysis for efficient systems

    International Nuclear Information System (INIS)

    Zogg, M.

    2000-01-01

    A life cycle analysis drawn up on behalf of the Swiss Federal Office of Energy shows that the combined cycle power plant + heat pump (GuD-WP) combination produces less greenhouse effect and makes only about half the contribution to summer smog formation as the operation of heat pumps with the power mix habitually used in Western Europe today. In the co-generation unit + heat pump (BHKW-WP) combination, the environmental impact shows the same values as in current West European power generation

  8. Proposing a novel combined cycle for optimal exergy recovery of liquefied natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Salimpour, M.R.; Zahedi, M.A. [Isfahan University of Technology (Iran, Islamic Republic of). Department of Mechanical Engineering

    2012-08-15

    The effective utilization of the cryogenic exergy associated with liquefied natural gas (LNG) vaporization is important. In this paper, a novel combined power cycle is proposed which utilizes LNG in different ways to enhance the power generation of a power plant. In addition to the direct expansion in the appropriate expander, LNG is used as a low-temperature heat sink for a middle-pressure gas cycle which uses nitrogen as working fluid. Also, LNG is used to cool the inlet air of an open Brayton gas turbine cycle. These measures are accomplished to improve the exergy recovery of LNG. In order to analyze the performance of the system, the influence of several key parameters such as pressure ratio of LNG turbine, ratio of the mass flow rate of LNG to the mass flow rate of air, pressure ratio of different compressors, LNG pressure and inlet pressure of nitrogen compressor, on the thermal efficiency and exergy efficiency of the offered cycle is investigated. Finally, the proposed combined cycle is optimized on the basis of first and second laws of thermodynamics. (orig.)

  9. Performance evaluation of combined ejector LiBr/H2O absorption cooling cycle

    Directory of Open Access Journals (Sweden)

    Hasan Sh. Majdi

    2016-03-01

    Full Text Available The objective of this work is to develop a computer simulation program to evaluate the performance of solar-assited combined ejector absorption (single-effect cooling system using LiBr/H2O as a working fluid and operating under steady-state conditions. The ejector possess no moving parts and is simple and reliable, which makes it attractive for combination with single-stage absorption cycle for further improvement to the system's performance. In this research, improvement to the system is achieved by utilizing the potential kinetic energy of the ejector to enhance refrigeration efficiency. The effects of the entrainment ratio of the ejector, operating temperature, on the thermal loads, and system performance have been investigated. The results showed that the evaporator and condenser loads, post-addition of the ejector, is found to be permanently higher than that in the basic cycle, which indicates a significant enhancement of the proposed cycle and the cooling capacity of the system increasing with the increase in evaporator temperature and entrainment ratio. The COP of the modified cycle is improved by up to 60 % compared with that of the basic cycle at the given condition. This process stabilizes the refrigeration system, enhanced its function, and enabled the system to work under higher condenser temperatures.

  10. Procedure for cogeneration plant evaluation in Italy

    International Nuclear Information System (INIS)

    Bollettini, U.; Savelli, D.

    1992-01-01

    This paper develops a step-by-step approach to the evaluation of cogeneration plants for on-site power generation. The aim is to allow prospective cogeneration plant owners to build energy/cost efficient plants and to be able to make a proper assessment of eligible financial assistance which may be obtained through the provisions of energy conservation normatives and laws set up by the Italian National Energy Plan. The approach has three principal phases - the verification of the availability of the required human resources able to perform the plant evaluation (engineering, legal and business consultants), an energy/viability audit of any existing energy plant considered for retrofitting and, finally, the identification of the best technical/economic cogeneration alternative. The programmed set of evaluation tasks includes the determination of optimal contracts with ENEL (the Italian National Electricity Board), especially for the case of excess power to be ceded to the national grid, and the making of comparisons with reference cogeneration systems whose relative design/cost data are stored in existing computerized data bases

  11. CO2 recovery from cogeneration projects

    International Nuclear Information System (INIS)

    Rushing, S.A.

    2001-01-01

    There is a ready market for carbon dioxide for use in industrial processes as well as in food and beverage production. Recovering this gas from flue gas exhausts can provide extra income for cogeneration projects -as well as reducing emissions. (author)

  12. Cogeneration in the former Soviet Union

    International Nuclear Information System (INIS)

    Horak, W.C.

    1997-01-01

    The former Soviet Union made a major commitment to Cogeneration. The scale and nature of this commitment created a system conceptually different from Cogeneration in the west. The differences were both in scale, in political commitment, and in socio economic impact. This paper addresses some of the largest scale Cogeneration programs, the technology, and the residual impact of these programs. The integration of the Cogeneration and nuclear programs is a key focus of the paper. Soviet designed nuclear power plants were designed to produce both electricity and heat for residential and industrial uses. Energy systems used to implement this design approach are discussed. The significant dependence on these units for heat created an urgent need for continued operation during the winter. Electricity and heat are also produced in nuclear weapons production facilities, as well as power plants. The Soviets also had designed, and initiated construction of a number of nuclear power plants open-quotes ATETsclose quotes optimized for production of heat as well as electricity. These were canceled

  13. External financing of projects on cogeneration

    International Nuclear Information System (INIS)

    Contreras Olmedo, D.

    1993-01-01

    The Spanish Institute for Energy Saving and Diversification (IDAE), provides technical advisement and economical support to those industries requiring an improvement in the energy efficiency of their production chain. This paper focusses on administrative procedures to get external financing as one way to undertake the construction of cogeneration plants. Relationships among user, promoter and financier should be developed according to the outlined procedures. (Author)

  14. Combined methodology of optimization and life cycle inventory for a biomass gasification based BCHP system

    International Nuclear Information System (INIS)

    Wang, Jiang-Jiang; Yang, Kun; Xu, Zi-Long; Fu, Chao; Li, Li; Zhou, Zun-Kai

    2014-01-01

    Biomass gasification based building cooling, heating, and power (BCHP) system is an effective distributed energy system to improve the utilization of biomass resources. This paper proposes a combined methodology of optimization method and life cycle inventory (LCI) for the biomass gasification based BCHP system. The life cycle models including biomass planting, biomass collection-storage-transportation, BCHP plant construction and operation, and BCHP plant demolition and recycle, are constructed to obtain economic cost, energy consumption and CO 2 emission in the whole service-life. Then, the optimization model for the biomass BCHP system including variables, objective function and solution method are presented. Finally, a biomass BCHP case in Harbin, China, is optimized under different optimization objectives, the life-cycle performances including cost, energy and CO 2 emission are obtained and the grey incidence approach is employed to evaluate their comprehensive performances of the biomass BCHP schemes. The results indicate that the life-cycle cost, energy efficiency and CO 2 emission of the biomass BCHP system are about 41.9 $ MWh −1 , 41% and 59.60 kg MWh −1 respectively. The optimized biomass BCHP configuration to minimize the life-cycle cost is the best scheme to achieve comprehensive benefit including cost, energy consumption, renewable energy ratio, steel consumption, and CO 2 emission. - Highlights: • Propose the combined method of optimization and LCI for biomass BCHP system. • Optimize the biomass BCHP system to minimize the life-cycle cost, energy and emission. • Obtain the optimized life-cycle cost, energy efficiency and CO 2 emission. • Select the best biomass BCHP scheme using grey incidence approach

  15. Improvement of performance operation and cycle efficiency of Al Anbar combined power plant

    International Nuclear Information System (INIS)

    Jabbar, Mohammed Q.

    2014-01-01

    The present work will be focusing on available solution which can serve to increase total efficiency of Al Anbar combined cycle power plant - CCPP, and thus to improve the operation performance as much as possible in order to decrease hydrocarbon, CO2, NOx emissions to environment.The simulation and calculations were performed by program software cycle-tempo software. The results were compared with basic design of Alanbar power plant after making modernization with solar tower receiver system-STRS, which represented a heat source in preheat process for a compressor air. Key Words: CCPP, STRS, Solar potential energy, fuel consumption, hydrocarbon emission

  16. Cogeneration Technology Alternatives Study (CTAS). Volume 3: Energy conversion system characteristics

    Science.gov (United States)

    1980-01-01

    Six current and thirty-six advanced energy conversion systems were defined and combined with appropriate balance of plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a frame work for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Fuel energy savings of 10 to 25 percent were predicted compared to traditional on site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal derived fuels, or coal with advanced fluid bed combustion or on site gasifications. Data and information for both current and advanced energy conversion technology are presented. Schematic and physical descriptions, performance data, equipment cost estimates, and predicted emissions are included. Technical developments which are needed to achieve commercialization in the 1985-2000 period are identified.

  17. The benefit of regional diversification of cogeneration investments in Europe. A mean-variance portfolio analysis

    International Nuclear Information System (INIS)

    Westner, Guenther; Madlener, Reinhard

    2010-01-01

    The EU Directive 2004/8/EC, concerning the promotion of cogeneration, established principles on how EU member states can support combined heat and power generation (CHP). Up to now, the implementation of these principles into national law has not been uniform, and has led to the adoption of different promotion schemes for CHP across the EU member states. In this paper, we first give an overview of the promotion schemes for CHP in various European countries. In a next step, we take two standard CHP technologies, combined-cycle gas turbines (CCGT-CHP) and engine-CHP, and apply exemplarily four selected support mechanisms used in the four largest European energy markets: feed-in tariffs in Germany; energy efficiency certificates in Italy; benefits through tax reduction in the UK; and purchase obligations for power from CHP generation in France. For contracting companies, it could be of interest to diversify their investment in new CHP facilities regionally over several countries in order to reduce country and regulatory risk. By applying the Mean-Variance Portfolio (MVP) theory, we derive characteristic return-risk profiles of the selected CHP technologies in different countries. The results show that the returns on CHP investments differ significantly depending on the country, the support scheme, and the selected technology studied. While a regional diversification of investments in CCGT-CHP does not contribute to reducing portfolio risks, a diversification of investments in engine-CHP can decrease the risk exposure. (author)

  18. Feasibility study on revamping work for a cogeneration power plant at Cherkassy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    With an objective of saving energy and reducing greenhouse gas emission, investigations and discussions were given on modification of Cherkassyoblenegro Combined Heat and Power Station in the Republic of Ukraine. The project calls for shutdown of the first block and the heat supplying auxiliary boilers being the oldest facilities in the existing station, and utilization of the second block for emergency use. The new facilities will consist of natural gas burning gas turbine combined cycle cogeneration facilities of 200-MW class including two gas turbines, one steam turbine, two each of waste heat recovery boilers, ducts and stacks. As a result of the discussions, if the project execution period is set for 20 years, the energy saving effect would be 144,215 tons of crude oil equivalent annually, and the greenhouse gas emission reducing effect would be 431,421 t-CO2 annually. The total fund amount required for the project is estimated to be 185,700,000 dollars. With regard to the profitability, the internal profit rate for the total fund after tax would be 8.3%, and the principal and interest repayment multiplying factor for single year would be greater than 1.9, whereas the profitability can be anticipated if the financing is available under generous conditions. (NEDO)

  19. The benefit of regional diversification of cogeneration investments in Europe. A mean-variance portfolio analysis

    Energy Technology Data Exchange (ETDEWEB)

    Westner, Guenther; Madlener, Reinhard [E.ON Energy Projects GmbH, Arnulfstrasse 56, 80335 Munich (Germany)

    2010-12-15

    The EU Directive 2004/8/EC, concerning the promotion of cogeneration, established principles on how EU member states can support combined heat and power generation (CHP). Up to now, the implementation of these principles into national law has not been uniform, and has led to the adoption of different promotion schemes for CHP across the EU member states. In this paper, we first give an overview of the promotion schemes for CHP in various European countries. In a next step, we take two standard CHP technologies, combined-cycle gas turbines (CCGT-CHP) and engine-CHP, and apply exemplarily four selected support mechanisms used in the four largest European energy markets: feed-in tariffs in Germany; energy efficiency certificates in Italy; benefits through tax reduction in the UK; and purchase obligations for power from CHP generation in France. For contracting companies, it could be of interest to diversify their investment in new CHP facilities regionally over several countries in order to reduce country and regulatory risk. By applying the Mean-Variance Portfolio (MVP) theory, we derive characteristic return-risk profiles of the selected CHP technologies in different countries. The results show that the returns on CHP investments differ significantly depending on the country, the support scheme, and the selected technology studied. While a regional diversification of investments in CCGT-CHP does not contribute to reducing portfolio risks, a diversification of investments in engine-CHP can decrease the risk exposure. (author)

  20. Combined heat and power considered as a virtual steam cycle heat pump

    International Nuclear Information System (INIS)

    Lowe, Robert

    2011-01-01

    The first aim of this paper is to shed light on the thermodynamic reasons for the practical pursuit of low temperature operation by engineers involved in the design and the operation of combined heat and power (CHP) and district heating (DH) systems. The paper shows that the steam cycle of a combined heat and power generator is thermodynamically equivalent to a conventional steam cycle generator plus an additional virtual steam cycle heat pump. This apparently novel conceptualisation leads directly to (i) the observed sensitivity of coefficient of performance of CHP to supply and return temperatures in associated DH systems, and (ii) the conclusion that the performance of CHP will tend to be significantly higher than real heat pumps operating at similar temperatures. The second aim, which is pursued more qualitatively, is to show that the thermodynamic performance advantages of CHP are consistent with the goal of deep, long-term decarbonisation of industrialised economies. As an example, estimates are presented, which suggest that CHP based on combined-cycle gas turbines with carbon capture and storage has the potential to reduce the carbon intensity of delivered heat by a factor of ∼30, compared with a base case of natural gas-fired condensing boilers. - Highlights: → Large-scale CHP systems are thermodynamically equivalent to virtual steam cycle heat pumps. → COPs of such virtual heat pumps are necessarily better than the Carnot limit for real heat pumps. → COPs can approach 9 for plant matched to district heating systems with flow temperatures of 90 deg. C. → CHP combined with CCGT and CCS can reduce the carbon intensity of delivered heat ∼30-fold.

  1. Optimization of fog inlet air cooling system for combined cycle power plants using genetic algorithm

    International Nuclear Information System (INIS)

    Ehyaei, Mehdi A.; Tahani, Mojtaba; Ahmadi, Pouria; Esfandiari, Mohammad

    2015-01-01

    In this research paper, a comprehensive thermodynamic modeling of a combined cycle power plant is first conducted and the effects of gas turbine inlet fogging system on the first and second law efficiencies and net power outputs of combined cycle power plants are investigated. The combined cycle power plant (CCPP) considered for this study consist of a double pressure heat recovery steam generator (HRSG) to utilize the energy of exhaust leaving the gas turbine and produce superheated steam to generate electricity in the Rankine cycle. In order to enhance understanding of this research and come up with optimum performance assessment of the plant, a complete optimization is using a genetic algorithm conducted. In order to achieve this goal, a new objective function is defined for the system optimization including social cost of air pollution for the power generation systems. The objective function is based on the first law efficiency, energy cost and the external social cost of air pollution for an operational system. It is concluded that using inlet air cooling system for the CCPP system and its optimization results in an increase in the average output power, first and second law efficiencies by 17.24%, 3.6% and 3.5%, respectively, for three warm months of year. - Highlights: • To model the combined cycle power plant equipped with fog inlet air cooling method. • To conduct both exergy and economic analyses for better understanding. • To conduct a complete optimization using a genetic algorithm to determine the optimal design parameters of the system

  2. Numerical simulation of divergent rocket-based-combined-cycle performances under the flight condition of Mach 3

    Science.gov (United States)

    Cui, Peng; Xu, WanWu; Li, Qinglian

    2018-01-01

    Currently, the upper operating limit of the turbine engine is Mach 2+, and the lower limit of the dual-mode scramjet is Mach 4. Therefore no single power systems can operate within the range between Mach 2 + and Mach 4. By using ejector rockets, Rocket-based-combined-cycle can work well in the above scope. As the key component of Rocket-based-combined-cycle, the ejector rocket has significant influence on Rocket-based-combined-cycle performance. Research on the influence of rocket parameters on Rocket-based-combined-cycle in the speed range of Mach 2 + to Mach 4 is scarce. In the present study, influences of Mach number and total pressure of the ejector rocket on Rocket-based-combined-cycle were analyzed numerically. Due to the significant effects of the flight conditions and the Rocket-based-combined-cycle configuration on Rocket-based-combined-cycle performances, flight altitude, flight Mach number, and divergence ratio were also considered. The simulation results indicate that matching lower altitude with higher flight Mach numbers can increase Rocket-based-combined-cycle thrust. For another thing, with an increase of the divergent ratio, the effect of the divergent configuration will strengthen and there is a limit on the divergent ratio. When the divergent ratio is greater than the limit, the effect of divergent configuration will gradually exceed that of combustion on supersonic flows. Further increases in the divergent ratio will decrease Rocket-based-combined-cycle thrust.

  3. Comparison of algae cultivation methods for bioenergy production using a combined life cycle assessment and life cycle costing approach.

    Science.gov (United States)

    Resurreccion, Eleazer P; Colosi, Lisa M; White, Mark A; Clarens, Andres F

    2012-12-01

    Algae are an attractive energy source, but important questions still exist about the sustainability of this technology on a large scale. Two particularly important questions concern the method of cultivation and the type of algae to be used. This present study combines elements of life cycle analysis (LCA) and life cycle costing (LCC) to evaluate open pond (OP) systems and horizontal tubular photobioreactors (PBRs) for the cultivation of freshwater (FW) or brackish-to-saline water (BSW) algae. Based on the LCA, OPs have lower energy consumption and greenhouse gas emissions than PBRs; e.g., 32% less energy use for construction and operation. According to the LCC, all four systems are currently financially unattractive investments, though OPs are less so than PBRs. BSW species deliver better energy and GHG performance and higher profitability than FW species in both OPs and PBRs. Sensitivity analyses suggest that improvements in critical cultivation parameters (e.g., CO(2) utilization efficiency or algae lipid content), conversion parameters (e.g., anaerobic digestion efficiency), and market factors (e.g., costs of CO(2) and electricity, or sale prices for algae biodiesel) could alter these results. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Assessment of Environmental and Economic Impacts of Vine-Growing Combining Life Cycle Assessment, Life Cycle Costing and Multicriterial Analysis

    Directory of Open Access Journals (Sweden)

    Giacomo Falcone

    2016-08-01

    Full Text Available The wine sector is going through a significant evolution dealing with the challenges of competition issues in international markets and with necessary commitments to sustainability improvement. In the wine supply chain, the agricultural phase represents a potential source of pollution and costs. From the farmers’ point of view, these contexts require them to be more attentive and find a compromise among environmental benefits, economic benefits, and costs linked to farming practices. This paper aims to make a sustainability assessment of different wine-growing scenarios located in Calabria (Southern Italy that combines conflicting insights, i.e., environmental and economic ones, by applying Life Cycle Assessment (LCA and Life Cycle Costing (LCC to identify the main hotspots and select the alternative scenarios closest to the ideal solution through the VIKOR multicriteria method. In particular, the latter allowed us to obtain synthetic indices for a two-dimensional sustainability assessment. Conventional practices associated to the espalier training system represent the best compromise from both environmental and economic points of view, due to the higher yield per hectare. The choices regarding Functional Unit (FU and indicators were shown to have a high influence on results.

  5. Reviving manufacturing with a federal cogeneration policy

    International Nuclear Information System (INIS)

    Brown, Marilyn A.; Cox, Matt; Baer, Paul

    2013-01-01

    Improving the energy economics of manufacturing is essential to revitalizing the industrial base of advanced economies. This paper evaluates ex-ante a federal policy option aimed at promoting industrial cogeneration—the production of heat and electricity in a single energy-efficient process. Detailed analysis using the National Energy Modeling System (NEMS) and spreadsheet calculations suggest that industrial cogeneration could meet 18% of U.S. electricity requirements by 2035, compared with its current 8.9% market share. Substituting less efficient utility-scale power plants with cogeneration systems would produce numerous economic and environmental benefits, but would also create an assortment of losers and winners. Multiple perspectives to benefit/cost analysis are therefore valuable. Our results indicate that the federal cogeneration policy would be highly favorable to manufacturers and the public sector, cutting energy bills, generating billions of dollars in electricity sales, making producers more competitive, and reducing pollution. Most traditional utilities, on the other hand, would lose revenues unless their rate recovery procedures are adjusted to prevent the loss of profits due to customer owned generation and the erosion of utility sales. From a public policy perspective, deadweight losses would be introduced by market-distorting federal incentives (ranging annually from $30 to $150 million), but these losses are much smaller than the estimated net social benefits of the federal cogeneration policy. - Highlights: ► Industrial cogeneration could meet 18% of US electricity demand by 2035, vs. 8.9% today. ► The policy would be highly favorable to manufacturers and the public. ► Traditional electric utilities would likely lose revenues. ► Deadweight loss would be introduced by tax incentives. ► The policy’s net social benefits would be much larger.

  6. Thermodynamic analysis of combined cycle under design/off-design conditions for its efficient design and operation

    International Nuclear Information System (INIS)

    Zhang, Guoqiang; Zheng, Jiongzhi; Xie, Angjun; Yang, Yongping; Liu, Wenyi

    2016-01-01

    Highlights: • Based on the PG9351FA gas turbine, two gas-steam combined cycles are redesigned. • Analysis of detailed off-design characteristics of the combined cycle main parts. • Suggestions for improving design and operation performance of the combined cycle. • Higher design efficiency has higher off-design efficiency in general PR range. • High pressure ratio combined cycles possess good off-design performance. - Abstract: To achieve a highly efficient design and operation of combined cycles, this study analyzed in detail the off-design characteristics of the main components of three combined cycles with different compressor pressure ratios (PRs) based on real units. The off-design model of combined cycle was built consisting of a compressor, a combustor, a gas turbine, and a heat recovery steam generator (HRSG). The PG9351FA unit is selected as the benchmark unit, on the basis of which the compressor is redesigned with two different PRs. Then, the design/off-design characteristics of the three units with different design PRs and the interactive relations between topping and bottoming cycles are analyzed with the same turbine inlet temperature (TIT). The results show that the off-design characteristics of the topping cycle affect dramatically the combined cycle performance. The variation range of the exergy efficiency of the topping cycle for the three units is between 11.9% and 12.4% under the design/off-design conditions. This range is larger than that of the bottoming cycle (between 9.2% and 9.5%). The HRSG can effectively recycle the heat/heat exergy of the gas turbine exhaust. Comparison among the three units shows that for a traditional gas-steam combined cycle, a high design efficiency results in a high off-design efficiency in the usual PR range. The combined cycle design efficiency of higher pressure ratio is almost equal to that of the PG9351FA, but its off-design efficiency is higher (maximum 0.42%) and the specific power decreases. As for

  7. Base-Load and Peak Electricity from a Combined Nuclear Heat and Fossil Combined-Cycle Plant

    International Nuclear Information System (INIS)

    Conklin, Jim; Forsberg, Charles W.

    2007-01-01

    A combined-cycle power plant is proposed that uses heat from a high-temperature reactor and fossil fuel to meet base-load and peak electrical demands. The high-temperature gas turbine produces shaft power to turn an electric generator. The hot exhaust is then fed to a heat recovery steam generator (HRSG) that provides steam to a steam turbine for added electrical power production. A simplified computational model of the thermal power conversion system was developed in order to parametrically investigate two different steady-state operation conditions: base load nuclear heat only from an Advanced High Temperature Reactor (AHTR), and combined nuclear heat with fossil heat to increase the turbine inlet temperature. These two cases bracket the expected range of power levels, where any intermediate power level can result during electrical load following. The computed results indicate that combined nuclear-fossil systems have the potential to offer both low-cost base-load electricity and lower-cost peak power relative to the existing combination of base-load nuclear plants and separate fossil-fired peak-electricity production units. In addition, electric grid stability, reduced greenhouse gases, and operational flexibility can also result with using the conventional technology presented here for the thermal power conversion system coupled with the AHTR

  8. Environmental impact efficiency of natural gas combined cycle power plants: A combined life cycle assessment and dynamic data envelopment analysis approach.

    Science.gov (United States)

    Martín-Gamboa, Mario; Iribarren, Diego; Dufour, Javier

    2018-02-15

    The energy sector is still dominated by the use of fossil resources. In particular, natural gas represents the third most consumed resource, being a significant source of electricity in many countries. Since electricity production in natural gas combined cycle (NGCC) plants provides some benefits with respect to other non-renewable technologies, it is often seen as a transitional solution towards a future low‑carbon power generation system. However, given the environmental profile and operational variability of NGCC power plants, their eco-efficiency assessment is required. In this respect, this article uses a novel combined Life Cycle Assessment (LCA) and dynamic Data Envelopment Analysis (DEA) approach in order to estimate -over the period 2010-2015- the environmental impact efficiencies of 20 NGCC power plants located in Spain. A three-step LCA+DEA method is applied, which involves data acquisition, calculation of environmental impacts through LCA, and the novel estimation of environmental impact efficiency (overall- and term-efficiency scores) through dynamic DEA. Although only 1 out of 20 NGCC power plants is found to be environmentally efficient, all plants show a relatively good environmental performance with overall eco-efficiency scores above 60%. Regarding individual periods, 2011 was -on average- the year with the highest environmental impact efficiency (95%), accounting for 5 efficient NGCC plants. In this respect, a link between high number of operating hours and high environmental impact efficiency is observed. Finally, preliminary environmental benchmarks are presented as an additional outcome in order to further support decision-makers in the path towards eco-efficiency in NGCC power plants. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Thermodynamic analysis on theoretical models of cycle combined heat exchange process: The reversible heat exchange process

    International Nuclear Information System (INIS)

    Zhang, Chenghu; Li, Yaping

    2017-01-01

    Concept of reversible heat exchange process as the theoretical model of the cycle combined heat exchanger could be useful to determine thermodynamics characteristics and the limitation values in the isolated heat exchange system. In this study, the classification of the reversible heat exchange processes is presented, and with the numerical method, medium temperature variation tendency and the useful work production and usage in the whole process are investigated by the construction and solution of the mathematical descriptions. Various values of medium inlet temperatures and heat capacity ratio are considered to analyze the effects of process parameters on the outlet temperature lift/drop. The maximum process work transferred from the Carnot cycle region to the reverse cycle region is also researched. Moreover, influence of the separating point between different sub-processes on temperature variation profile and the process work production are analyzed. In addition, the heat-exchange-enhancement-factor is defined to study the enhancement effect of the application of the idealized process in the isolated heat exchange system, and the variation degree of this factor with process parameters change is obtained. The research results of this paper can be a theoretical guidance to construct the cycle combined heat exchange process in the practical system. - Highlights: • A theoretical model of Cycle combined heat exchange process is proposed. • The classification of reversible heat exchange process are presented. • Effects of Inlet temperatures and heat capacity ratio on process are analyzed. • Process work transmission through the whole process is studied. • Heat-exchange-enhancement-factor can be a criteria to express the application effect of the idealized process.

  10. Tariffs for natural gas, heat, electricity and cogeneration in 1998

    International Nuclear Information System (INIS)

    1998-03-01

    The rate of return of the combined generation of heat and power is not only determined by the capital expenditures and the costs of maintenance, control, management and insurance, but also by the fuel costs of the cogeneration installation and the avoided fuel costs in case of separated heat production, the avoided/saved costs of electricity purchase, and the compensation for possible supply to the public grid (sellback). This brochure aims at providing information about the structure of natural gas and electricity tariffs to be able to determine the three last-mentioned expenditures. First, attention is paid to the tariffs of natural gas for large-scale consumers, the tariff for cogeneration and horticulture, and natural gas supply contracts. Next, the structure of the electricity tariffs is dealt with in detail, discussing the accounting system within the electric power sector, the tariffs and compensations for large-scale consumers and specific large-scale consumers, electricity sellback tariffs, and compensations for reserve capacity. Also attention will be paid to tariffs for electricity transport. Finally, several taxes, excises and levies that have a direct or indirect impact on natural gas tariffs, are discussed. 9 refs

  11. Nuclear hydrogen - cogeneration and the transitional pathway to sustainable development

    International Nuclear Information System (INIS)

    Gurbin, G.M.; Talbot, K.H.

    1994-01-01

    The development of the next phase of the Bruce Energy Centre, in cooperation with Ontario Hydro, will see the introduction of a series of integrated energy processes whose end products will have environmental value added. Cogenerated nuclear steam and electricity were selected on the basis of economics, sustainability and carbon emissions. The introduction of hydrogen to combine with CO 2 from alcohol fermentation provided synthetic methanol as a feedstock to refine into ether for the rapidly expanding gasoline fuel additive market, large volumes of O 2 will enhance combustion processes and improve closed-looping of the systems. In the implementation of the commercial development, the first stage will require simultaneous electrolysis, methanol synthesis and additional fermentation capacity. Electricity and steam pricing will be key to viability and an 80-MV 'backup' fossil-fuelled, back pressure turbine cogeneration facility could be introduced in a compatible matter. Successful demonstration of transitional and integrating elements necessary to achieve sustainable development can serve as a model for electric utilities throughout the world. 11 ref., 1 tab., 4 figs

  12. Economic optimization of the combined cycle integrated with multi-product gasification system

    International Nuclear Information System (INIS)

    Liszka, M.; Ziebik, A.

    2009-01-01

    The system taken into consideration consists of the Corex unit, combined cycle power plant and air separation unit (ASU). The Corex process (trademark of Siemens-VAI) is one of technologies for cokeless hot metal production. Coal is gasified by oxygen in the hot metal environment. The excess gas can be used out of installation. It has been assumed that the Corex export gas is fired in combined cycle. The gas turbine (GT) structure was assumed as a fixed simple cycle while the heat recovery steam generator (HRSG) and steam turbine arrangements are free for optimization. The examples of independent variables selected for optimization are number of HRSG pressure levels, GT pressure ratio, minimal temperature differences in HRSG, flow rate of compressed air form GT compressor to ASU. Finally, 16 independent variables have been qualified for optimization. The synthesis optimization is based on the superstructure method. The economic net present value (NPV) has been chosen as the objective function. All power plant facilities have been modeled on the GateCycle software. The off-design models include, among others, the GT blade cooling and HRSG heat transfer coefficient analyses. Two optimization methods - genetic algorithm and Powells conjugate directions have been coupled in one hybrid procedure. The whole optimization analysis has been repeated several times for different price scenarios on the coal, iron and electricity markets

  13. Integrated operation and management system for a 700MW combined cycle power plant

    Energy Technology Data Exchange (ETDEWEB)

    Shiroumaru, I. (Yanai Power Plant Construction Office, Chugoku Electric Power Co., Inc., 1575-5 Yanai-Miyamoto-Shiohama, Yanai-shi, Yamaguchi-ken (JP)); Iwamiya, T. (Omika Works, Hitachi, Ltd., 5-2-1 Omika-cho, Hitachi-shi, Ibaraki-ken (JP)); Fukai, M. (Hitachi Works, Hitachi, Ltd., 3-1-1 Saiwai-cho, Hitachi-shi, Ibaraki-ken (JP))

    1992-03-01

    Yanai Power Plant of the Chugoku Electric Power Co., Inc. (Yamaguchi Pref., Japan) is in the process of constructing a 1400MW state-of-the-art combined cycle power plant. The first phase, a 350MW power plant, started operation on a commercial basis in November, 1990. This power plant has achieved high efficiency and high operability, major features of a combined cycle power plant. The integrated operation and management system of the power plant takes care of operation, maintenance, control of general business, etc., and was built using the latest computer and digital control and communication technologies. This paper reports that it is expected that this system will enhance efficient operation and management for the power plant.

  14. Optimisation of Combined Cycle Gas Turbine Power Plant in Intraday Market: Riga CHP-2 Example

    Directory of Open Access Journals (Sweden)

    Ivanova P.

    2018-02-01

    Full Text Available In the research, the influence of optimised combined cycle gas turbine unit – according to the previously developed EM & OM approach with its use in the intraday market – is evaluated on the generation portfolio. It consists of the two combined cycle gas turbine units. The introduced evaluation algorithm saves the power and heat balance before and after the performance of EM & OM approach by making changes in the generation profile of units. The aim of this algorithm is profit maximisation of the generation portfolio. The evaluation algorithm is implemented in multi-paradigm numerical computing environment MATLab on the example of Riga CHP-2. The results show that the use of EM & OM approach in the intraday market can be profitable or unprofitable. It depends on the initial state of generation units in the intraday market and on the content of the generation portfolio.

  15. Environmental Assessment for the Warren Station externally fired combined cycle demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The proposed Penelec project is one of 5 projects for potential funding under the fifth solicitation under the Clean Coal Technology program. In Penelec, two existing boilers would be replaced at Warren Station, PA; the new unit would produce 73 MW(e) in a combined cycle mode (using both gas-fired and steam turbines). The project would fill the need for a full utility-size demonstration of externally fire combined cycle (EFCC) technology as the next step toward commercialization. This environmental assessment was prepared for compliance with NEPA; its purpose is to provide sufficient basis for determining whether to prepare an environmental impact statement or to issue a finding of no significant impact. It is divided into the sections: purpose and need for proposed action; alternatives; brief description of affected environment; environmental consequences, including discussion of commercial operation beyond the demonstration period.

  16. Optimisation of Combined Cycle Gas Turbine Power Plant in Intraday Market: Riga CHP-2 Example

    Science.gov (United States)

    Ivanova, P.; Grebesh, E.; Linkevics, O.

    2018-02-01

    In the research, the influence of optimised combined cycle gas turbine unit - according to the previously developed EM & OM approach with its use in the intraday market - is evaluated on the generation portfolio. It consists of the two combined cycle gas turbine units. The introduced evaluation algorithm saves the power and heat balance before and after the performance of EM & OM approach by making changes in the generation profile of units. The aim of this algorithm is profit maximisation of the generation portfolio. The evaluation algorithm is implemented in multi-paradigm numerical computing environment MATLab on the example of Riga CHP-2. The results show that the use of EM & OM approach in the intraday market can be profitable or unprofitable. It depends on the initial state of generation units in the intraday market and on the content of the generation portfolio.

  17. Exchange of availability/performance data on base-load gas turbine and combined cycle plant

    Energy Technology Data Exchange (ETDEWEB)

    Jesuthasan, D.K.; Kaupang, B.M. (Tenaga Nasional Berhad (Malaysia))

    1992-09-01

    This paper describes the recommendations developed to facilitate the international exchange of availability performance data on base-load gas turbines and combined cycle plant. Standardized formats for the collection of plant availability statistics, recognizing the inherent characteristics of gas turbines in simple and combined cycle plants are presented. The formats also allow for a logical expansion of the data collection detail as that becomes desirable. To assist developing countries in particular, the approach includes basic formats for data collection needed for international reporting. In addition, the participating utilities will have a meaningful database for internal use. As experience is gained with this data colletion system, it is expected that additional detail may be accommodated to enable further in-depth performance analysis on the plant and on the utility level. 2 refs., 2 tabs., 11 apps.

  18. The reliability of integrated gasification combined cycle (IGCC) power generation units

    Energy Technology Data Exchange (ETDEWEB)

    Higman, C.; DellaVilla, S.; Steele, B. [Syngas Consultants Ltd. (United Kingdom)

    2006-07-01

    This paper presents two interlinked projects aimed at supporting the improvement of integrated gasification combined cycle (IGCC) reliability. The one project comprises the extension of SPS's existing ORAP (Operational Reliability Analysis Program) reliability, availability and maintainability (RAM) tracking technology from its existing base in natural gas open and combined cycle operations into IGCC. The other project is using the extended ORAP database to evaluate performance data from existing plants. The initial work has concentrated on evaluating public domain data on the performance of gasification based power and chemical plants. This is being followed up by plant interviews in some 20 plants to verify and expand the database on current performance. 23 refs., 8 figs., 2 tabs.

  19. Thermodynamic analysis and conceptual design for partial coal gasification air preheating coal-fired combined cycle

    Science.gov (United States)

    Xu, Yue; Wu, Yining; Deng, Shimin; Wei, Shirang

    2004-02-01

    The partial coal gasification air pre-heating coal-fired combined cycle (PGACC) is a cleaning coal power system, which integrates the coal gasification technology, circulating fluidized bed technology, and combined cycle technology. It has high efficiency and simple construction, and is a new selection of the cleaning coal power systems. A thermodynamic analysis of the PGACC is carried out. The effects of coal gasifying rate, pre-heating air temperature, and coal gas temperature on the performances of the power system are studied. In order to repower the power plant rated 100 MW by using the PGACC, a conceptual design is suggested. The computational results show that the PGACC is feasible for modernizing the old steam power plants and building the new cleaning power plants.

  20. Tunisia- British gas intends to participate to the building of a combined cycle electric power plant

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    Here is described the project to build a combined-cycle power plant in Tunisia, project in which the British Gas is interested. The transport, distribution, import and export of electricity should be controlled by the Tunisian society of electricity and gas. In the context of an agreement with Gec-Alsthom, the british company hopes to offer to build, and exploit the future power plant. (N.C.)

  1. Integrated gasification combined-cycle research development and demonstration activities in the US

    Energy Technology Data Exchange (ETDEWEB)

    Ness, H.M.; Brdar, R.D.

    1996-09-01

    The United States Department of Energy (DOE)`s Office of Fossil Energy, Morgantown Energy Technology Center, is managing a research development and demonstration (RD&D) program that supports the commercialization of integrated gasification combined-cycle (IGCC) advanced power systems. This overview briefly describes the supporting RD&D activities and the IGCC projects selected for demonstration in the Clean Coal Technology (CCT) Program.

  2. Pressurized fluidized bed combustion combined cycle power plant with coal gasification: Second generation pilot plant

    International Nuclear Information System (INIS)

    Farina, G.L.; Bressan, L.

    1991-01-01

    This paper presents the technical and economical background of a research and development program of a novel power generation scheme, which is based on coal gasification, pressurized fluid bed combustion and combined cycles. The participants in this program are: Foster Wheeler (project leader), Westinghouse, IGT and the USA Dept. of Energy. The paper describes the characteristics of the plant, the research program in course of implementation, the components of the pilot plant and the first results obtained

  3. Energetic and exergetic analysis of combined cycle Energas Boca de Jaruco

    International Nuclear Information System (INIS)

    Dominguez, F. J.; Tapanez, A.; Castillo, E. del; Castillo, R.; Perez, R.

    2015-01-01

    The work shows the energy and exergy evaluation of the combined cycle Energas Boca de Jaruco, which consists of five gas turbines 30 MWh five heat recovery steam OTSGs type and a steam turbine of 150 MW. This evaluation is performed without additional burning and for different percentages of utilization of these burners. The results allow to have a criterion of the efficiency of the system with and without supplementary burned, which can define strategies most appropriate system operation. (full text)

  4. Thermoeconomic Analysis and Optimization of a New Combined Supercritical Carbon Dioxide Recompression Brayton/Kalina Cycle

    Directory of Open Access Journals (Sweden)

    S. Mohammad S. Mahmoudi

    2016-10-01

    Full Text Available A new combined supercritical CO2 recompression Brayton/Kalina cycle (SCRB/KC is proposed. In the proposed system, waste heat from a supercritical CO2 recompression Brayton cycle (SCRBC is recovered by a Kalina cycle (KC to generate additional electrical power. The performances of the two cycles are simulated and compared using mass, energy and exergy balances of the overall systems and their components. Using the SPECO (Specific Exergy Costing approach and employing selected cost balance equations for the components of each system, the total product unit costs of the cycles are obtained. Parametric studies are performed to investigate the effects on the SCRB/KC and SCRBC thermodynamic and thermoeconomic performances of key decision parameters. In addition, considering the exergy efficiency and total product unit cost as criteria, optimization is performed for the SCRBC and SCRB/KC using Engineering Equation Solver software. The results indicate that the maximum exergy efficiency of the SCRB/KC is higher than that of the SCRBC by up to 10%, and that the minimum total product unit cost of the SCRB/KC is lower than that of the SCRBC by up to 4.9%.

  5. HTR-Based Power Plants’ Performance Analysis Applied on Conventional Combined Cycles

    Directory of Open Access Journals (Sweden)

    José Carbia Carril

    2015-01-01

    Full Text Available In high temperature reactors including gas cooled fast reactors and gas turbine modular helium reactors (GT-MHR specifically designed to operate as power plant heat sources, efficiency enhancement at effective cost under safe conditions can be achieved. Mentioned improvements concern the implementation of two cycle structures: (a, a stand alone Brayton operating with helium and a stand alone Rankine cycle (RC with regeneration, operating with carbon dioxide at ultrasupercritical pressure as working fluid (WF, where condensation is carried out at quasicritical conditions, and (b, a combined cycle (CC, in which the topping closed Brayton cycle (CBC operates with helium as WF, while the bottoming RC is operated with one of the following WFs: carbon dioxide, xenon, ethane, ammonia, or water. In both cases, an intermediate heat exchanger (IHE is proposed to provide thermal energy to the closed Brayton or to the Rankine cycles. The results of the case study show that the thermal efficiency, through the use of a CC, is slightly improved (from 45.79% for BC and from 50.17% for RC to 53.63 for the proposed CC with He-H2O operating under safety standards.

  6. Generating power at high efficiency combined cycle technology for sustainable energy production

    CERN Document Server

    Jeffs, E

    2008-01-01

    Combined cycle technology is used to generate power at one of the highest levels of efficiency of conventional power plants. It does this through primary generation from a gas turbine coupled with secondary generation from a steam turbine powered by primary exhaust heat. Generating power at high efficiency thoroughly charts the development and implementation of this technology in power plants and looks to the future of the technology, noting the advantages of the most important technical features - including gas turbines, steam generator, combined heat and power and integrated gasification com

  7. Integration of energy-efficient empty fruit bunch drying with gasification/combined cycle systems

    International Nuclear Information System (INIS)

    Aziz, Muhammad; Prawisudha, Pandji; Prabowo, Bayu; Budiman, Bentang Arief

    2015-01-01

    Highlights: • Novel integrated drying, gasification and combined cycle for empty fruit bunch. • Application of enhanced process integration to achieve high total energy efficiency. • The technology covers exergy recovery and process integration. • High overall energy efficiency can be achieved (about 44% including drying). - Abstract: A high-energy-efficient process for empty fruit bunch drying with integration to gasification and combined cycle processes is proposed. The enhancement is due to greater exergy recovery and more efficient process integration. Basically, the energy/heat involved in a single process is recovered as much as possible, leading to minimization of exergy destruction. In addition, the unrecoverable energy/heat is utilized for other processes through process integration. During drying, a fluidized bed dryer with superheated steam is used as the main evaporator. Exergy recovery is performed through exergy elevation via compression and effective heat coupling in a dryer and heat exchangers. The dried empty fruit bunches are gasified in a fluidized bed gasifier using air as the fluidizing gas. Furthermore, the produced syngas is utilized as fuel in the combined cycle module. From process analysis, the proposed integrated processes can achieve a relatively high energy efficiency. Compared to a standalone drying process employing exergy recovery, the proposed integrated drying can reduce consumed energy by about 1/3. In addition, the overall integrated processes can reach a total power generation efficiency of about 44%

  8. Analysis of energetic and exergetic efficiency, and environmental benefits of biomass integrated gasification combined cycle technology.

    Science.gov (United States)

    Mínguez, María; Jiménez, Angel; Rodríguez, Javier; González, Celina; López, Ignacio; Nieto, Rafael

    2013-04-01

    The problem of the high carbon dioxide emissions linked to power generation makes necessary active research on the use of biofuels in gas turbine systems as a promising alternative to fossil fuels. Gasification of biomass waste is particularly of interest in obtaining a fuel to be run in gas turbines, as it is an efficient biomass-to-biofuel conversion process, and an integration into a combined cycle power plant leads to a high performance with regard to energetic efficiency. The goal of this study was to carry out an energetic, exergetic and environmental analysis of the behaviour of an integrated gasification combined cycle (IGCC) plant fuelled with different kinds of biomass waste by means of simulations. A preliminary economic study is also included. Although a technological development in gasification technology is necessary, the results of simulations indicate a high technical and environmental interest in the use of biomass integrated gasification combined cycle (BioIGCC) systems for large-scale power generation from biomass waste.

  9. First image from a combined positron emission tomography and field-cycled MRI system.

    Science.gov (United States)

    Bindseil, Geron A; Gilbert, Kyle M; Scholl, Timothy J; Handler, William B; Chronik, Blaine A

    2011-07-01

    Combining positron emission tomography and MRI modalities typically requires using either conventional MRI with a MR-compatible positron emission tomography system or a modified MR system with conventional positron emission tomography. A feature of field-cycled MRI is that all magnetic fields can be turned off rapidly, enabling the use of conventional positron emission tomography detectors based on photomultiplier tubes. In this demonstration, two photomultiplier tube-based positron emission tomography detectors were integrated with a field-cycled MRI system (0.3 T/4 MHz) by placing them into a 9-cm axial gap. A positron emission tomography-MRI phantom consisting of a triangular arrangement of positron-emitting point sources embedded in an onion was imaged in a repeating interleaved sequence of ∼1 sec MRI then 1 sec positron emission tomography. The first multimodality images from the combined positron emission tomography and field-cycled MRI system show no additional artifacts due to interaction between the systems and demonstrate the potential of this approach to combining positron emission tomography and MRI. Copyright © 2010 Wiley-Liss, Inc.

  10. Combined cycle versus one thousand diesel power plants: pollutant emissions, ecological efficiency and economic analysis

    International Nuclear Information System (INIS)

    Silveira, Jose Luz; de Carvalho, Joao Andrade; de Castro Villela, Iraides Aparecida

    2007-01-01

    The increase in the use of natural gas in Brazil has stimulated public and private sectors to analyse the possibility of using combined cycle systems for generation of electrical energy. Gas turbine combined cycle power plants are becoming increasingly common due to their high efficiency, short lead times, and ability to meet environmental standards. Power is produced in a generator linked directly to the gas turbine. The gas turbine exhaust gases are sent to a heat recovery steam generator to produce superheated steam that can be used in a steam turbine to produce additional power. In this paper a comparative study between a 1000 MW combined cycle power plant and 1000kW diesel power plant is presented. In first step, the energetic situation in Brazil, the needs of the electric sector modification and the needs of demand management and integrated means planning are clarified. In another step the characteristics of large and small thermoelectric power plants that use natural gas and diesel fuel, respectively, are presented. The ecological efficiency levels of each type of power plant is considered in the discussion, presenting the emissions of particulate material, sulphur dioxide (SO 2 ), carbon dioxide (CO 2 ) and nitrogen oxides (NO x ). (author)

  11. Technical and economic assessment of the integrated solar combined cycle power plants in Iran

    International Nuclear Information System (INIS)

    Soltani Hosseini, M.; Hosseini, R.; Valizadeh, G.H.

    2002-01-01

    Thermal efficiency, capacity factor, environmental considerations, investment cost, fuel and O and M costs are the main parameters for technical and economic assessment of solar power plants. This analysis has shown that the Integrated Solar Combined Cycle System with 67 MW e solar field(ISCCS-67) is the most suitable plan for the first solar power plant in Iran. The Levelized Energy Costs of combined cycle and ISCCS-67 power plants would be equal if 49 million dollars of ISCCS-67 capital cost supplied by the international environmental organizations such as Global Environmental Facilities and World Bank. This study shows that an ISCCS-67 saves 59 million dollars in fuel consumption and reduces about 2.4 million ton in CO 2 emission during 30 years operating period. Increasing of steam turbine capacity by 50%, and 4% improvement in overall efficiency are other advantages of iSCCS-67 power plant. The LEC of ISCCS-67 is 10% and so 33% lower than the combined cycle and gas turbine, respectively, at the same capacity factor with consideration of environmental costs

  12. Numerical analysis and field study of time dependent exergy-energy of a gas-steam combined cycle

    Directory of Open Access Journals (Sweden)

    Barari Bamdad

    2012-01-01

    Full Text Available In this study, time dependent exergy analysis of the Fars Combined Power Plant Cycle has been investigated. Exergy analysis has been used for investigating each part of actual combined cycle by considering irreversibility from Apr 2006 to Oct 2010. Performance analysis has been done for each part by evaluating exergy destruction in each month. By using of exergy analysis, aging of each part has been evaluated respect to time duration. In addition, the rate of lost work for each month has been calculated and variation of this parameter has been considered as a function of aging rate. Finally, effects of exergy destruction of each part have been investigated on exergy destruction of whole cycle. Entire analysis has been done for Unit 3 and 4 of gas turbine cycle which combined by Unit B of steam cycle in Fars Combined Power Plant Cycle located in Fars province in Iran.

  13. Co-generation at CERN Beneficial or not?

    CERN Document Server

    Wilhelmsson, M

    1998-01-01

    A co-generation plant for the combined production of electricity and heat has recently been installed on the CERN Meyrin site. This plant consists of: a gas turbine generator set (GT-set), a heat recovery boiler for the connection to the CERN primary heating network, as well as various components for the integration on site. A feasibility study was carried out and based on the argument that the combined use of natural gas -available anyhow for heating purposes- gives an attractively high total efficiency, which will, in a period of time, pay off the investment. This report will explain and update the calculation model, thereby confirming the benefits of the project. The results from the commissioning tests will be taken into account, as well as the benefits to be realized under the condition that the plant can operate undisturbed by technical setbacks which, incidentally, has not been entirely avoided during the first year of test-run and operation.

  14. Performance analysis of an Integrated Solar Combined Cycle using Direct Steam Generation in parabolic trough collectors

    International Nuclear Information System (INIS)

    Montes, M.J.; Rovira, A.; Munoz, M.; Martinez-Val, J.M.

    2011-01-01

    Highlights: → Solar hybridization improves the performance of CCGT in a very hot and dry weather. → The scheme analyzed is a DSG parabolic trough field coupled to the Rankine cycle. → An annual simulation has been carried out for two locations: Almeria and Las Vegas. → Economical analysis shows that this scheme is a cheaper way to exploit solar energy. → For that, solar hybridization must be limited to a small fraction of the CCGT power. - Abstract: The contribution of solar thermal power to improve the performance of gas-fired combined cycles in very hot and dry environmental conditions is analyzed in this work, in order to assess the potential of this technique, and to feature Direct Steam Generation (DSG) as a well suited candidate for achieving very good results in this quest. The particular Integrated Solar Combined Cycle (ISCC) power plant proposed consists of a DSG parabolic trough field coupled to the bottoming steam cycle of a Combined Cycle Gas Turbine (CCGT) power plant. For this analysis, the solar thermal power plant performs in a solar dispatching mode: the gas turbine always operates at full load, only depending on ambient conditions, whereas the steam turbine is somewhat boosted to accommodate the thermal hybridization from the solar field. Although the analysis is aimed to studying such complementary effects in the widest perspective, two relevant examples are given, corresponding to two well-known sites: Almeria (Spain), with a mediterranean climate, and Las Vegas (USA), with a hot and dry climate. The annual simulations show that, although the conventional CCGT power plant works worse in Las Vegas, owing to the higher temperatures, the ISCC system operates better in Las Vegas than in Almeria, because of solar hybridization is especially well coupled to the CCGT power plant in the frequent days with great solar radiation and high temperatures in Las Vegas. The complementary effect will be clearly seen in these cases, because the thermal

  15. Advanced gas turbine cycles a brief review of power generation thermodynamics

    CERN Document Server

    Horlock, JH

    2003-01-01

    Primarily this book describes the thermodynamics of gas turbine cycles. The search for high gas turbine efficiency has produced many variations on the simple ""open circuit"" plant, involving the use of heat exchangers, reheating and intercooling, water and steam injection, cogeneration and combined cycle plants. These are described fully in the text. A review of recent proposals for a number of novel gas turbine cycles is also included. In the past few years work has been directed towards developing gas turbines which produce less carbon dioxide, or plants from which the CO2 can be d

  16. Modeling of a Cogeneration System with a Micro Gas Turbine Operating at Partial Load Conditions

    Directory of Open Access Journals (Sweden)

    José Carlos Dutra

    2017-06-01

    Full Text Available The integration of absorption chillers in micro-cogeneration systems based on micro-gas turbines can be useful as an appropriate strategy to increase the total system energy efficiency. Since it is an area intensive in technology, it is necessary to develop and use models of simulation, which can predict the behavior of the whole system and of each component individually, at different operating conditions. This work is part of a research project in high efficiency cogeneration systems, whose purpose at this stage is to model a micro-cogeneration system, which is composed of a micro gas turbine, Capstone C30, a compact cross flow finned tube heat exchanger and an absorption chiller. The entire model is composed of specifically interconnected models, developed and validated for each component. The simulation of the microturbine used a thermodynamic analytic model, which contains a procedure used to obtain the micro turbine characteristic performance curves, which is closed with the thermodynamic Brayton cycle model. In the cogeneration system discussed in this paper, the compact heat exchanger was used to heat thermal oil, which drives an absorption chiller. It was designed, characterized and installed in a cogeneration system installed at the Centre d'Innovació Tecnològica en Revalorització Energètica i Refrigeració, Universtat Rovira i Virgili. Its design led to the heat exchanger model, which was coupled with the micro turbine model. Presented in this work is a comparison between the data from the model and the experiments, demonstrating good agreement between both results.

  17. Optimization of advenced liquid natural gas-fuelled combined cycle machinery systems for a high-speed ferry

    DEFF Research Database (Denmark)

    Tveitaskog, Kari Anne; Haglind, Fredrik

    2012-01-01

    . Furthermore, practical and operational aspects of using these three machinery systems for a high-speed ferry are discussed. Two scenarios are evaluated. The first scenario evaluates the combined cycles with a given power requirement, optimizing the combined cycle while operating the gas turbine at part load...

  18. Carbon exergy tax applied to biomass integrated gasification combined cycle in sugarcane industry

    International Nuclear Information System (INIS)

    Fonseca Filho, Valdi Freire da; Matelli, José Alexandre; Perrella Balestieri, José Antonio

    2016-01-01

    The development of technologies based on energy renewable sources is increasing worldwide in order to diversify the energy mix and satisfy the rigorous environmental legislation and international agreements to reduce pollutant emission. Considering specific characteristics of biofuels available in Brazil, studies regarding such technologies should be carried out aiming energy mix diversification. Several technologies for power generation from biomass have been presented in the technical literature, and plants with BIGCC (biomass integrated gasification combined cycle) emerge as a major technological innovation. By obtaining a fuel rich in hydrogen from solid biomass gasification, BIGCC presents higher overall process efficiency than direct burning of the solid fuel in conventional boilers. The objective of this paper is to develop a thermodynamic and chemical equilibrium model of a BIGCC configuration for sugarcane bagasse. The model embodies exergetic cost and CO_2 emission analyses through the method of CET (carbon exergy tax). An exergetic penalty comparison between the BIGCC technology (with and without CO_2 capture and sequestration), a natural gas combined cycle and the traditional steam cycle of sugarcane sector is then presented. It is verified that the BIGCC configuration with CO_2 capture and sequestration presents technical and environmental advantages when compared to traditional technology. - Highlights: • We compared thermal cycles with the exergetic carbon exergy tax. • Thermal cycles with and without carbon capture and sequestration were considered. • Burned and gasified sugarcane bagasse was assumed as renewable fuel. • Exergetic carbon penalty tax was imposed to all studied configurations. • BIGCC with carbon sequestration revealed to be advantageous.

  19. Thermodynamic analysis of engineering solutions aimed at raising the efficiency of integrated gasification combined cycle

    Science.gov (United States)

    Gordeev, S. I.; Bogatova, T. F.; Ryzhkov, A. F.

    2017-11-01

    Raising the efficiency and environmental friendliness of electric power generation from coal is the aim of numerous research groups today. The traditional approach based on the steam power cycle has reached its efficiency limit, prompted by materials development and maneuverability performance. The rival approach based on the combined cycle is also drawing nearer to its efficiency limit. However, there is a reserve for efficiency increase of the integrated gasification combined cycle, which has the energy efficiency at the level of modern steam-turbine power units. The limit of increase in efficiency is the efficiency of NGCC. One of the main problems of the IGCC is higher costs of receiving and preparing fuel gas for GTU. It would be reasonable to decrease the necessary amount of fuel gas in the power unit to minimize the costs. The effect can be reached by raising of the heat value of fuel gas, its heat content and the heat content of cycle air. On the example of the process flowsheet of the IGCC with a power of 500 MW, running on Kuznetsk bituminous coal, by means of software Thermoflex, the influence of the developed technical solutions on the efficiency of the power plant is considered. It is received that rise in steam-air blast temperature to 900°C leads to an increase in conversion efficiency up to 84.2%. An increase in temperature levels of fuel gas clean-up to 900°C leads to an increase in the IGCC efficiency gross/net by 3.42%. Cycle air heating reduces the need for fuel gas by 40% and raises the IGCC efficiency gross/net by 0.85-1.22%. The offered solutions for IGCC allow to exceed net efficiency of analogous plants by 1.8-2.3%.

  20. Natural gas cogeneration in the residential sector; La cogeneration au gaz naturel en residentiel

    Energy Technology Data Exchange (ETDEWEB)

    Lancelot, C.; Gaudin, S. [Gaz de France, GDF, Dir. de la Recherche, 75 - Paris (France)

    2000-07-01

    The natural gas cogeneration offer is now available and operational in the industrial sector. It is based on technologies of piston engines and gas turbines. Currently, this offer is sufficiently diversified, so much from the point of view of the range of powers available (from 1 MW to more than 40 MW electric) that number of manufacturers. In order to widen the cogeneration market in France to the markets of the commercial and residential sectors, Gaz De France has undertaken a technical economic study to validate the potential of those markets. This study led to work on the assembly of a french die to cogeneration packages of low power (less than 1 MW electric). This step has emerged at the beginning of 1999 with the launching of a commercial offer of cogeneration packages. In margin to this work Gaz De France Research division also initiated a study in order to evaluate the offer of micro cogeneration, products delivering an electric output lower than 10 kW. (authors)

  1. A novel cogeneration system: A proton exchange membrane fuel cell coupled to a heat transformer

    International Nuclear Information System (INIS)

    Huicochea, A.; Romero, R.J.; Rivera, W.; Gutierrez-Urueta, G.; Siqueiros, J.; Pilatowsky, I.

    2013-01-01

    This study focuses on the potential of a novel cogeneration system which consists of a 5 kW proton exchange membrane fuel cell (PEMFC) and an absorption heat transformer (AHT). The dissipation heat resulting from the operation of the PEMFC would be used to feed the absorption heat transformer, which is integrated to a water purification system. Therefore, the products of the proposed cogeneration system are heat, electricity and distilled water. The study includes a simulation for the PEMFC as well as experimental results obtained with an experimental AHT facility. Based on the simulation results, experimental tests were performed in order to estimate the performance parameters of the overall system. This is possible due to the matching in power and temperatures between the outlet conditions of the simulated fuel cell and the inlet requirements of the AHT. Experimental coefficients of performance are reported for the AHT as well as the overall cogeneration efficiency for the integrated system. The results show that experimental values of coefficient of performance of the AHT and the overall cogeneration efficiency, can reach up to 0.256 and 0.571, respectively. This represents an increment in 12.4% of efficiency, compared to the fuel cell efficiency working individually. This study shows that the combined use of AHT systems with a PEMFC is possible and it is a very feasible project to be developed in the Centro de Investigación en Energía (Centre of Energy Research), México.

  2. Externally-fired combined cycle: An effective coal fueled technology for repowering and new generation

    Energy Technology Data Exchange (ETDEWEB)

    Stoddard, L.E.; Bary, M.R. [Black and Veatch, Kansas City, MO (United States); Gray, K.M. [Pennsylvania Electric Co., Johnstown, PA (United States); LaHaye, P.G. [Hague International, South Portland, ME (United States)

    1995-06-01

    The Externally-Fired Combined Cycle (EFCC) is an attractive emerging technology for powering high efficiency combined gas and steam turbine cycles with coal or other ash bearing fuels. In the EFCC, the heat input to a gas turbine is supplied indirectly through a ceramic air heater. The air heater, along with an atmospheric coal combustor and ancillary equipment, replaces the conventional gas turbine combustor. A steam generator located downstream from the ceramic air heater and steam turbine cycle, along with an exhaust cleanup system, completes the combined cycle. A key element of the EFCC Development Program, the 25 MMBtu/h heat-input Kennebunk Test Facility (KTF), has recently begun operation. The KTF has been operating with natural gas and will begin operating with coal in early 1995. The US Department of Energy selected an EFCC repowering of the Pennsylvania Electric Company`s Warren Station for funding under the Clean Coal Technology Program Round V. The project focuses on repowering an existing 48 MW (gross) steam turbine with an EFCC power island incorporating a 30 MW gas turbine, for a gross power output of 78 MW and a net output of 72 MW. The net plant heat rate will be decreased by approximately 30% to below 9,700 Btu/kWh. Use of a dry scrubber and fabric filter will reduce sulfur dioxide (SO{sub 2}) and particulate emissions to levels under those required by the Clean Air Act Amendments (CAAA) of 1990. Nitrogen oxides (NO{sub x}) emissions are controlled by the use of staged combustion. The demonstration project is currently in the engineering phase, with startup scheduled for 1997. This paper discusses the background of the EFCC, the KTF, the Warren Station EFCC Clean Coal Technology Demonstration Project, the commercial plant concept, and the market potential for the EFCC.

  3. Investigation of thermodynamic performances for two solar-biomass hybrid combined cycle power generation systems

    International Nuclear Information System (INIS)

    Liu, Qibin; Bai, Zhang; Wang, Xiaohe; Lei, Jing; Jin, Hongguang

    2016-01-01

    Highlights: • Two solar-biomass hybrid combined cycle power generation systems are proposed. • The characters of the two proposed systems are compared. • The on-design and off-design properties of the system are numerically investigated. • The favorable performances of thermochemical hybrid routine are validated. - Abstract: Two solar-biomass hybrid combined cycle power generation systems are proposed in this work. The first system employs the thermochemical hybrid routine, in which the biomass gasification is driven by the concentrated solar energy, and the gasified syngas as a solar fuel is utilized in a combined cycle for generating power. The second system adopts the thermal integration concept, and the solar energy is directly used to heat the compressed air in the topping Brayton cycle. The thermodynamic performances of the developed systems are investigated under the on-design and off-design conditions. The advantages of the hybrid utilization technical mode are demonstrated. The solar energy can be converted and stored into the chemical fuel by the solar-biomass gasification, with the net solar-to-fuel efficiency of 61.23% and the net solar share of 19.01% under the specific gasification temperature of 1150 K. Meanwhile, the proposed system with the solar thermochemical routine shows more favorable behaviors, the annual system overall energy efficiency and the solar-to-electric efficiency reach to 29.36% and 18.49%, while the with thermal integration concept of 28.03% and 15.13%, respectively. The comparison work introduces a promising approach for the efficient utilization of the abundant solar and biomass resources in the western China, and realizes the mitigation of CO_2 emission.

  4. Aspen Plus simulation of biomass integrated gasification combined cycle systems at corn ethanol plants

    International Nuclear Information System (INIS)

    Zheng, Huixiao; Kaliyan, Nalladurai; Morey, R. Vance

    2013-01-01

    Biomass integrated gasification combined cycle (BIGCC) systems and natural gas combined cycle (NGCC) systems are employed to provide heat and electricity to a 0.19 hm 3 y −1 (50 million gallon per year) corn ethanol plant using different fuels (syrup and corn stover, corn stover alone, and natural gas). Aspen Plus simulations of BIGCC/NGCC systems are performed to study effects of different fuels, gas turbine compression pressure, dryers (steam tube or superheated steam) for biomass fuels and ethanol co-products, and steam tube dryer exhaust treatment methods. The goal is to maximize electricity generation while meeting process heat needs of the plant. At fuel input rates of 110 MW, BIGCC systems with steam tube dryers provide 20–25 MW of power to the grid with system thermal efficiencies (net power generated plus process heat rate divided by fuel input rate) of 69–74%. NGCC systems with steam tube dryers provide 26–30 MW of power to the grid with system thermal efficiencies of 74–78%. BIGCC systems with superheated steam dryers provide 20–22 MW of power to the grid with system thermal efficiencies of 53–56%. The life-cycle greenhouse gas (GHG) emission reduction for conventional corn ethanol compared to gasoline is 39% for process heat with natural gas (grid electricity), 117% for BIGCC with syrup and corn stover fuel, 124% for BIGCC with corn stover fuel, and 93% for NGCC with natural gas fuel. These GHG emission estimates do not include indirect land use change effects. -- Highlights: •BIGCC and natural gas combined cycle systems at corn ethanol plants are simulated. •The best performance results in 25–30 MW power to grid. •The best performance results in 74–78% system thermal efficiencies. •GHG reduction for corn ethanol with BIGCC systems compared to gasoline is over 100%

  5. Simulation of an integrated gasification combined cycle with chemical-looping combustion and carbon dioxide sequestration

    International Nuclear Information System (INIS)

    Jiménez Álvaro, Ángel; López Paniagua, Ignacio; González Fernández, Celina; Rodríguez Martín, Javier; Nieto Carlier, Rafael

    2015-01-01

    Highlights: • A chemical-looping combustion based integrated gasification combined cycle is simulated. • The energetic performance of the plant is analyzed. • Different hydrogen-content synthesis gases are under study. • Energy savings accounting carbon dioxide sequestration and storage are quantified. • A notable increase on thermal efficiency up to 7% is found. - Abstract: Chemical-looping combustion is an interesting technique that makes it possible to integrate power generation from fuels combustion and sequestration of carbon dioxide without energy penalty. In addition, the combustion chemical reaction occurs with a lower irreversibility compared to a conventional combustion, leading to attain a somewhat higher overall thermal efficiency in gas turbine systems. This paper provides results about the energetic performance of an integrated gasification combined cycle power plant based on chemical-looping combustion of synthesis gas. A real understanding of the behavior of this concept of power plant implies a complete thermodynamic analysis, involving several interrelated aspects as the integration of energy flows between the gasifier and the combined cycle, the restrictions in relation with heat balances and chemical equilibrium in reactors and the performance of the gas turbines and the downstream steam cycle. An accurate thermodynamic modeling is required for the optimization of several design parameters. Simulations to evaluate the energetic efficiency of this chemical-looping-combustion based power plant under diverse working conditions have been carried out, and a comparison with a conventional integrated gasification power plant with precombustion capture of carbon dioxide has been made. Two different synthesis gas compositions have been tried to check its influence on the results. The energy saved in carbon capture and storage is found to be significant and even notable, inducing an improvement of the overall power plant thermal efficiency of

  6. Energy-exergy analysis of compressor pressure ratio effects on thermodynamic performance of ammonia water combined cycle

    International Nuclear Information System (INIS)

    Mohtaram, Soheil; Chen, Wen; Zargar, T.; Lin, Ji

    2017-01-01

    Highlights: • Energy exergy analysis is conducted to find the effects of RP. • EES software is utilized to perform the detailed energy-exergy analyses. • Effects investigated through energy and exergy destruction, enthalpy, yields, etc. • Detailed results are reported showing the performance of gas and combined cycle. - Abstract: The purpose of this study is to investigate the effect of compressor pressure ratio (RP) on the thermodynamic performances of ammonia-water combined cycle through energy and exergy destruction, enthalpy temperature, yields, and flow velocity. The energy-exergy analysis is conducted on the ammonia water combined cycle and the Rankine cycle, respectively. Engineering Equation Solver (EES) software is utilized to perform the detailed analyses. Values and ratios regarding heat drop and exergy loss are presented in separate tables for different equipments. The results obtained by the energy-exergy analysis indicate that by increasing the pressure ratio compressor, exergy destruction of high-pressure compressors, intercooler, gas turbine and the special produced work of gas turbine cycle constantly increase and the exergy destruction of recuperator, in contrast, decreases continuously. In addition, the least amount of input fuel into the combined cycle is observed when the pressure ratio is no less than 7.5. Subsequently, the efficiency of the cycle in gas turbine and combined cycle is reduced because the fuel input into the combined cycle is increased.

  7. Real-world experience of women using extended-cycle vs monthly-cycle combined oral contraception in the United States: the National Health and Wellness Survey.

    Science.gov (United States)

    Nappi, Rossella E; Lete, Iñaki; Lee, Lulu K; Flores, Natalia M; Micheletti, Marie-Christine; Tang, Boxiong

    2018-01-18

    The real-world experience of women receiving extended-cycle combined oral contraception (COC) versus monthly-cycle COC has not been reported. Data were from the United States 2013 National Health and Wellness Survey. Eligible women (18-50 years old, premenopausal, without hysterectomy) currently using extended-cycle COC (3 months between periods) were compared with women using monthly-cycle COC. Treatment satisfaction (1 "extremely dissatisfied" to 7 "extremely satisfied"), adherence (8-item Morisky Medication Adherence Scale © ), menstrual cycle-related symptoms, health-related quality of life (HRQOL) and health state utilities (Medical Outcomes Short Form Survey-36v2®), depression (9-item Patient Health Questionnaire), sleep difficulties, Work Productivity and Activity Impairment-General Health, and healthcare resource use were assessed using one-way analyses of variance, chi-square tests, and generalized linear models (adjusted for covariates). Participants included 260 (6.7%) women using extended-cycle and 3616 (93.3%) using monthly-cycle COC. Women using extended-cycle COC reported significantly higher treatment satisfaction (P = 0.001) and adherence (P = 0.04) and reduced heavy menstrual bleeding (P = 0.029). A non-significant tendency toward reduced menstrual pain (39.5% versus 47.3%) and menstrual cycle-related symptoms (40.0% versus 48.7%) was found in women using extended-cycle versus monthly-cycle COC. Significantly more women using extended-cycle COC reported health-related diagnoses, indicating preferential prescription for extended-cycle COC among women reporting more health problems. Consistent with this poorer health, more women using extended-cycle COC reported fatigue, headache, and activity impairment (P values cycle COC as a valuable treatment option with high satisfaction, high adherence, and reduced heavy menstrual bleeding.

  8. Qualifying cogeneration in Texas and Louisiana

    International Nuclear Information System (INIS)

    Jenkins, S.C.; Cabe, R.; Stauffaeher, J.J.

    1992-01-01

    This paper reports that cogeneration of electricity and useful thermal energy by industrials along the Gulf Coast grew significantly more rapidly than in other parts of the country during and immediately following World War II as a result of the concentration of chemical and plastics processing facilities there. In 1982, Texas passed its version of PURPA, the Public Utility Regulatory Act (PURA) and designated those non-utility generators from which public utilities must purchase electricity as Qualifying Cogenerators. In 1991, there were nearly 7,500 MW of QF power generated for inside-the-fence use or firm capacity sale to utilities, with the two largest utilities in Texas purchasing over half that amount

  9. Development of Residential SOFC Cogeneration System

    Science.gov (United States)

    Ono, Takashi; Miyachi, Itaru; Suzuki, Minoru; Higaki, Katsuki

    2011-06-01

    Since 2001 Kyocera has been developing 1kW class Solid Oxide Fuel Cell (SOFC) for power generation system. We have developed a cell, stack, module and system. Since 2004, Kyocera and Osaka Gas Co., Ltd. have been developed SOFC residential co-generation system. From 2007, we took part in the "Demonstrative Research on Solid Oxide Fuel Cells" Project conducted by New Energy Foundation (NEF). Total 57 units of 0.7kW class SOFC cogeneration systems had been installed at residential houses. In spite of residential small power demand, the actual electric efficiency was about 40%(netAC,LHV), and high CO2 reduction performance was achieved by these systems. Hereafter, new joint development, Osaka Gas, Toyota Motors, Kyocera and Aisin Seiki, aims early commercialization of residential SOFC CHP system.

  10. Development of Residential SOFC Cogeneration System

    International Nuclear Information System (INIS)

    Ono, Takashi; Miyachi, Itaru; Suzuki, Minoru; Higaki, Katsuki

    2011-01-01

    Since 2001 Kyocera has been developing 1kW class Solid Oxide Fuel Cell (SOFC) for power generation system. We have developed a cell, stack, module and system. Since 2004, Kyocera and Osaka Gas Co., Ltd. have been developed SOFC residential co-generation system. From 2007, we took part in the 'Demonstrative Research on Solid Oxide Fuel Cells' Project conducted by New Energy Foundation (NEF). Total 57 units of 0.7kW class SOFC cogeneration systems had been installed at residential houses. In spite of residential small power demand, the actual electric efficiency was about 40%(netAC,LHV), and high CO2 reduction performance was achieved by these systems. Hereafter, new joint development, Osaka Gas, Toyota Motors, Kyocera and Aisin Seiki, aims early commercialization of residential SOFC CHP system.

  11. Natural gas cogeneration plants: considerations on energy efficiency

    International Nuclear Information System (INIS)

    Arcuri, P.; Florio, G.; Fragiacomo, P.

    1996-01-01

    Cogeneration is one of the most interesting solution to be adopted in order to achieve the goals of the Domestic Energy Plan. Besides the high primary energy savings, remarkable environmental benefits can be obtained. In the article, an energy analysis is carried out on the major cogeneration technologies depending on the parameters which define a generic user tipology. The energy indexes of a cogeneration plant are the shown in charts from which useful information on the achievable performances can be obtained

  12. Cogeneration. Section 2: Products and services

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    This is a directory of suppliers of products and services in the area of cogeneration. The subheadings of this directory include developers and owner operators, system packagers, manufacturers of prime movers, equipment manufacturers, instruments and controls manufacturing, consulting services, appraisal and valuation, computer services, environmental services, feasibility services, hydrology, marketing, measurements, meteorology, regulatory and licensing, research, testing, training and personnel, engineering and construction, operations and maintenance, and insurance, financial and legal services

  13. Efficient Use of Cogeneration and Fuel Diversification

    Directory of Open Access Journals (Sweden)

    Kunickis M.

    2015-12-01

    Full Text Available Energy policy of the European Community is implemented by setting various goals in directives and developing support mechanisms to achieve them. However, very often these policies and legislation come into contradiction with each other, for example Directive 2009/28/EC on the promotion of the use of energy from renewable sources and Directive 2012/27/EU on energy efficiency, repealing Directive 2004/8/EC on the promotion of cogeneration based on a useful heat demand.

  14. Intraday trade is the answer for cogeneration

    International Nuclear Information System (INIS)

    Lomme, J.J.

    2006-01-01

    It is possible for operators of small cogeneration plants to sell electricity on the day-ahead market of the Amsterdam Power Exchange (APX) or through the unbalance market of the Dutch power transmission operator TenneT. However, it is difficult for them to take part in the market. The solution could be a so-called intraday-market, in which electricity trade can be a continuous process, but the question is who will start such a market [nl

  15. Cogeneration: A marketing opportunity for pipelines

    International Nuclear Information System (INIS)

    Ulrich, J.S.

    1992-01-01

    This chapter describes the marketing of dual-purpose power plants by pipeline companies as a long term marketing strategy for natural gas. The author uses case studies to help evaluate a company's attitude toward development of a market for cogeneration facilities. The chapter focuses on strategies for developing markets in the industrial sector and identifying customer groups that are likely to respond in like manner to a marketing strategy

  16. Experience feedback from nuclear cogeneration - 15369

    International Nuclear Information System (INIS)

    Auriault, C.; Fuetterer, M.A.; Baudrand, O.

    2015-01-01

    A consortium of 20 companies currently runs the NC2I-R (Nuclear Cogeneration Industrial Initiative - Research) project as part of the European Union's 7. Framework Programme. The project supports the development of an industrial initiative to demonstrate nuclear cogeneration of heat and power as an effective low-carbon technology for industrial market applications. As part of this project, operational feedback was collected from previous, existing and planned nuclear cogeneration projects in a number of countries with the aim of identifying a most complete set of boundary conditions which led to successful projects in the past. Stakeholders consulted include in particular utilities and end users. The scope encompassed technical and non-technical information (organizational structure, financial aspects, public relations, etc.) and specifically experience in licensing gained from these projects. The information was collected by a questionnaire and additional face-to-face interviews. The questionnaire was formulated to cover 9 categories of in total 56 questions for 36 identified projects: Motivation and initiative, Role of key players, Organizational structure, Technical aspects, Safety and licensing, Financial aspects, Timing, Public relations, General experience feedback. From the 36 identified projects worldwide, 23 from 10 countries have provided feedback on a variety of applications such as district heating, seawater desalination, paper and pulp industry, petrochemical industry, coal gasification or salt processing. This is a surprisingly positive response considering that several of these projects date back to the 1980's and many of them were performed outside Europe. This paper summarizes and analyzes the received information and deduces from there which boundary conditions are favorable for the construction of new nuclear cogeneration projects. (authors)

  17. Combined cycle solar central receiver hybrid power system study. Final technical report. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    This study develops the conceptual design for a commercial-scale (nominal 100 MWe) central receiver solar/fossil fuel hybrid power system with combined cycle energy conversion. A near-term, metallic heat pipe receiver and an advanced ceramic tube receiver hybrid system are defined through parametric and market potential analyses. Comparative evaluations of the cost of power generation, the fuel displacement potential, and the technological readiness of these two systems indicate that the near-term hybrid system has better potential for commercialization by 1990. Based on the assessment of the conceptual design, major cost and performance improvements are projected for the near-term system. Constraints preventing wide-spread use were not identified. Energy storage is not required for this system and analyses show no economic advantages with energy storage provisions. It is concluded that the solar hybrid system is a cost effective alternative to conventional gas turbines and combined cycle generating plants, and has potential for intermediate-load market penetration at 15% annual fuel escalation rate. Due to their flexibility, simple solar/nonsolar interfacing, and short startup cycles, these hybrid plants have significant operating advantages. Utility company comments suggest that hybrid power systems will precede stand-alone solar plants.

  18. Influence of precooling cooling air on the performance of a gas turbine combined cycle

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Ik Hwan; Kang, Do Won; Kang, Soo Young; Kim, Tong Seop [Inha Univ., Incheon (Korea, Republic of)

    2012-02-15

    Cooling of hot sections, especially the turbine nozzle and rotor blades, has a significant impact on gas turbine performance. In this study, the influence of precooling of the cooling air on the performance of gas turbines and their combined cycle plants was investigated. A state of the art F class gas turbine was selected, and its design performance was deliberately simulated using detailed component models including turbine blade cooling. Off design analysis was used to simulate changes in the operating conditions and performance of the gas turbines due to precooling of the cooling air. Thermodynamic and aerodynamic models were used to simulate the performance of the cooled nozzle and rotor blade. In the combined cycle plant, the heat rejected from the cooling air was recovered at the bottoming steam cycle to optimize the overall plant performance. With a 200K decrease of all cooling air stream, an almost 1.78% power upgrade due to increase in main gas flow and a 0.70 percent point efficiency decrease due to the fuel flow increase to maintain design turbine inlet temperature were predicted.

  19. Comparison of Different Technologies for Integrated Solar Combined Cycles: Analysis of Concentrating Technology and Solar Integration

    Directory of Open Access Journals (Sweden)

    Antonio Rovira

    2018-04-01

    Full Text Available This paper compares the annual performance of Integrated Solar Combined Cycles (ISCCs using different solar concentration technologies: parabolic trough collectors (PTC, linear Fresnel reflectors (LFR and central tower receiver (CT. Each solar technology (i.e. PTC, LFR and CT is proposed to integrate solar energy into the combined cycle in two different ways. The first one is based on the use of solar energy to evaporate water of the steam cycle by means of direct steam generation (DSG, increasing the steam production of the high pressure level of the steam generator. The other one is based on the use of solar energy to preheat the pressurized air at the exit of the gas turbine compressor before it is introduced in the combustion chamber, reducing the fuel consumption. Results show that ISCC with DSG increases the yearly production while solar air heating reduces it due to the incremental pressure drop. However, air heating allows significantly higher solar-to-electricity efficiencies and lower heat rates. Regarding the solar technologies, PTC provides the best thermal results.

  20. High-Efficiency Small-Scale Combined Heat and Power Organic Binary Rankine Cycles

    Directory of Open Access Journals (Sweden)

    Costante Mario Invernizzi

    2018-04-01

    Full Text Available Small-CHP (Combined Heat and Power systems are generally considered a valuable technological option to the conventional boilers, in a technology developed context. If small-CHP systems are associated with the use of renewable energies (biomass, for example they could play an important role in distributed generation even in developing countries or, in any case, where there are no extensive electricity networks. Traditionally the considered heat engines for micro- or mini-CHP are: the gas engine, the gas turbine (with internal combustion, the steam engine, engine working according to the Stirling and to the Rankine cycles, the last with organic fluids. In principle, also fuel cells could be used. In this paper, we focus on small size Rankine cycles (10–15 k W with organic working fluids. The assumed heat source is hot combustion gases at high temperature (900–950 ∘ C and we assume to use only single stages axial turbines. The need to work at high temperatures, limits the choice of the right organic working fluids. The calculation results show the limitation in the performances of simple cycles and suggest the opportunity to resort to complex (binary cycle configurations to achieve high net conversion efficiencies (15–16%.

  1. Numerical optimization of Combined Heat and Power Organic Rankine Cycles – Part A: Design optimization

    International Nuclear Information System (INIS)

    Martelli, Emanuele; Capra, Federico; Consonni, Stefano

    2015-01-01

    This two-part paper proposes an approach based on state-of-the-art numerical optimization methods for simultaneously determining the most profitable design and part-load operation of Combined Heat and Power Organic Rankine Cycles. Compared to the usual design practice, the important advantages of the proposed approach are (i) to consider the part-load performance of the ORC at the design stage, (ii) to optimize not only the cycle variables, but also the main turbine design variables (number of stages, stage loads, rotational speed). In this first part (Part A), the design model and the optimization algorithm are presented and tested on a real-world test case. PGS-COM, a recently proposed hybrid derivative-free algorithm, allows to efficiently tackle the challenging non-smooth black-box problem. - Highlights: • Algorithm for the simultaneous optimization Organic Rakine Cycle and turbine. • Thermodynamic and economic models of boiler, cycle, turbine are developed. • Non-smooth black-box optimization problem is successfully tackled with PGS-COM. • Test cases show that the algorithm returns optimal solutions within 4 min. • Toluene outperforms MDM (a siloxane) in terms of efficiency and costs.

  2. Gas turbine modular helium reactor in cogeneration

    International Nuclear Information System (INIS)

    Leon de los Santos, G.

    2009-10-01

    This work carries out the thermal evaluation from the conversion of nuclear energy to electric power and process heat, through to implement an outline gas turbine modular helium reactor in cogeneration. Modeling and simulating with software Thermo flex of Thermo flow the performance parameters, based on a nuclear power plant constituted by an helium cooled reactor and helium gas turbine with three compression stages, two of inter cooling and one regeneration stage; more four heat recovery process, generating two pressure levels of overheat vapor, a pressure level of saturated vapor and one of hot water, with energetic characteristics to be able to give supply to a very wide gamma of industrial processes. Obtaining a relationship heat electricity of 0.52 and efficiency of net cogeneration of 54.28%, 70.2 MW net electric, 36.6 MW net thermal with 35% of condensed return to 30 C; for a supplied power by reactor of 196.7 MW; and with conditions in advanced gas turbine of 850 C and 7.06 Mpa, assembly in a shaft, inter cooling and heat recovery in cogeneration. (Author)

  3. EXERGETIC ANALYSIS OF A COGENERATION POWER PLANT

    Directory of Open Access Journals (Sweden)

    Osvaldo Manuel Nuñez Bosch

    2016-07-01

    Full Text Available Cogeneration power plants connected to industrial processes have a direct impact on the overall efficiency of the plant and therefore on the economic results. Any modification to the thermal outline of these plants must first include an exergetic analysis to compare the benefits it can bring the new proposal. This research is performed to a cogeneration plant in operation with an installed electrical capacity of 24 MW and process heat demand of 190 MW, it shows a study made from the Second Law of Thermodynamics. Exergetic evaluation of each component of the plant was applied and similarly modified cogeneration scheme was evaluated. The results illustrate that the exergy losses and irreversibilities are completely different from one subsystem to another. In general, the total exergy destruction represented 70,7% from the primary fuel exergy. Steam generator was the subsystem with the highest irreversibility of the plant with 54%. It was demonstrated that the increase of the steam parameters lead to reduce exergy destruction and exergy efficiency elevation. The suppression of the reduction system and the adding of an extraction-condensing steam turbine produce the same effect and contribute to drop off the electrical consumption from the grid.

  4. Guide to Combined Heat and Power Systems for Boiler Owners and Operators

    Energy Technology Data Exchange (ETDEWEB)

    Oland, CB

    2004-08-19

    Combined heat and power (CHP) or cogeneration is the sequential production of two forms of useful energy from a single fuel source. In most CHP applications, chemical energy in fuel is converted to both mechanical and thermal energy. The mechanical energy is generally used to generate electricity, while the thermal energy or heat is used to produce steam, hot water, or hot air. Depending on the application, CHP is referred to by various names including Building Cooling, Heating, and Power (BCHP); Cooling, Heating, and Power for Buildings (CHPB); Combined Cooling, Heating, and Power (CCHP); Integrated Energy Systems (IES), or Distributed Energy Resources (DER). The principal technical advantage of a CHP system is its ability to extract more useful energy from fuel compared to traditional energy systems such as conventional power plants that only generate electricity and industrial boiler systems that only produce steam or hot water for process applications. By using fuel energy for both power and heat production, CHP systems can be very energy efficient and have the potential to produce electricity below the price charged by the local power provider. Another important incentive for applying cogeneration technology is to reduce or eliminate dependency on the electrical grid. For some industrial processes, the consequences of losing power for even a short period of time are unacceptable. The primary objective of the guide is to present information needed to evaluate the viability of cogeneration for new or existing industrial, commercial, and institutional (ICI) boiler installations and to make informed CHP equipment selection decisions. Information presented is meant to help boiler owners and operators understand the potential benefits derived from implementing a CHP project and recognize opportunities for successful application of cogeneration technology. Topics covered in the guide follow: (1) an overview of cogeneration technology with discussions about benefits

  5. Thermal-CFD Analysis of Combined Solar-Nuclear Cycle Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Fathi, Nima [Univ. of New Mexico, Albuquerque, NM (United States); McDaniel, Patrick [Univ. of New Mexico, Albuquerque, NM (United States); Vorobieff, Peter [Univ. of New Mexico, Albuquerque, NM (United States); de Oliveira, Cassiano [Univ. of New Mexico, Albuquerque, NM (United States); Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Aleyasin, Seyed Sobhan [Univ. of Manitoba (Canada)

    2015-09-01

    The aim of this paper is evaluating the efficiency of a novel combined solar-nuclear cycle. CFD-Thermal analysis is performed to apply the available surplus heat from the nuclear cycle and measure the available kinetic energy of air for the turbine of a solar chimney power plant system (SCPPS). The presented idea helps to decrease the thermal pollution and handle the water shortage supply for water plant by replacing the cooling tower by solar chimney power plant to get the surplus heat from the available warm air in the secondary loop of the reactor. By applying this idea to a typical 1000 MW nuclear power plant with a 0.33 thermal efficiency, we can increase it to 0.39.

  6. Numerical Model of a Variable-Combined-Cycle Engine for Dual Subsonic and Supersonic Cruise

    Directory of Open Access Journals (Sweden)

    Victor Fernandez-Villace

    2013-02-01

    Full Text Available Efficient high speed propulsion requires exploiting the cooling capability of the cryogenic fuel in the propulsion cycle. This paper presents the numerical model of a combined cycle engine while in air turbo-rocket configuration. Specific models of the various heat exchanger modules and the turbomachinery elements were developed to represent the physical behavior at off-design operation. The dynamic nature of the model allows the introduction of the engine control logic that limits the operation of certain subcomponents and extends the overall engine operational envelope. The specific impulse and uninstalled thrust are detailed while flying a determined trajectory between Mach 2.5 and 5 for varying throttling levels throughout the operational envelope.

  7. Modern combined cycle power plant utilizing the GT11N2

    International Nuclear Information System (INIS)

    Goodwin, J.C.

    1992-01-01

    The requirement imposed on modern power plants are increasingly demanding. The limits of: efficiency; environmental sensitivity; reliability and availability; are constantly being pushed. Today's state of the art combined cycle power plants are positioned well to meet these challenges. This paper reports that these objectives can be achieved through the selection of the proper gas turbine generator in an optimized cycle concept. A balanced approach to the plant design is required. It must not sacrifice any one of these requirements, in order to achieve the others. They achieve their fullest potential when firing a clean fuel, natural gas. However, fuel oil, both light (No. 2) and heavy (No. 6), can be utilized but some efficiency and environmental impact will have to be sacrificed

  8. Evaluation of alternatives of exothermic methanization cycle for combined electricity and heat generation

    International Nuclear Information System (INIS)

    Balajka, J.; Princova, H.

    1987-01-01

    The possibilities are discussed of using the ADAM-EVA system for remote heat supply from nuclear heat sources to district heating systems. Attention is devoted to the use of the exothermal methanization process (ADAM station) for the combined power and heat production, this making use of the existing hot water power distribution network. The basic parameter for the evaluation of the over-all efficiency of the combined power and heat production is the maximum methanization cycle temperature which depends on the life of the methanization catalyst. Upon temperature drop below 550 degC, the conversion process can only be secured by means of two-stage methanization, which leads to a simplification of the cycle and a reduction in investment cost. At a temperature lower than 500 degC, combined power and heat production cannot be implemented. On the contrary, a considerable amount of electric power supplied from outside the system would be needed for compression work. (Z.M.)

  9. Effect of combined β-alanine and sodium bicarbonate supplementation on cycling performance.

    Science.gov (United States)

    Bellinger, Phillip M; Howe, Samuel T; Shing, Cecilia M; Fell, James W

    2012-08-01

    The purpose of this study was to investigate the effects of 28 d of β-alanine supplementation on 4-min cycling time trial performance and to determine whether there was an additive effect of combined β-alanine and sodium bicarbonate (NaHCO3) supplementation on high-intensity cycling performance. Fourteen highly trained cyclists (mean ± SD: age = 25.4 ± 7.2 yr, mass = 71.1 ± 7.1 kg, V˙O(2max) = 66.6 ± 5.7 mL·kg·min) supplemented for 28 d with β-alanine (65 mg·kg body mass each day) or placebo. A maximal 4-min bout of cycling was performed before supplementation (baseline) and twice after supplementation: after ingestion of NaHCO3 (300 mg·kg body mass) and ingestion of a placebo using a randomized crossover design with 2 d between trials. Blood pH and HCO3 concentration were determined before loading (postsupplementation trials) and at pretest and posttest. In the acute NaHCO3 loading trials, blood pH and HCO3 were elevated from before loading to pretest, and the magnitude of the change in HCO3 from pretest to posttest was significantly greater compared with the acute placebo loading trial (P < 0.001). Average power output in the 4-min cycling performance trial was increased in placebo + NaHCO3 (+3.1% ± 1.8%) and β-alanine + NaHCO3 (+3.3% ± 3.0%) compared with baseline (P < 0.05). β-alanine + placebo did not significantly improve average power output compared with baseline (+1.6% ± 1.7%, P = 0.20); however, magnitude-based inferences demonstrated that β-alanine + placebo was associated with a 37% likelihood of producing average power improvements. In trained cyclists, β-alanine supplementation did not significantly improve 4-min cycling performance; however, there may be a small meaningful improvement in performance. Acute NaHCO3 supplementation significantly improved 4-min cycling performance. There seemed to be a minimal additive effect of combined β-alanine and NaHCO3 supplementation.

  10. Dynamic Testing of the NASA Hypersonic Project Combined Cycle Engine Testbed for Mode Transition Experiments

    Science.gov (United States)

    2011-01-01

    NASA is interested in developing technology that leads to more routine, safe, and affordable access to space. Access to space using airbreathing propulsion systems has potential to meet these objectives based on Airbreathing Access to Space (AAS) system studies. To this end, the NASA Fundamental Aeronautics Program (FAP) Hypersonic Project is conducting fundamental research on a Turbine Based Combined Cycle (TBCC) propulsion system. The TBCC being studied considers a dual flow-path inlet system. One flow-path includes variable geometry to regulate airflow to a turbine engine cycle. The turbine cycle provides propulsion from take-off to supersonic flight. The second flow-path supports a dual-mode scramjet (DMSJ) cycle which would be initiated at supersonic speed to further accelerate the vehicle to hypersonic speed. For a TBCC propulsion system to accelerate a vehicle from supersonic to hypersonic speed, a critical enabling technology is the ability to safely and effectively transition from the turbine to the DMSJ-referred to as mode transition. To experimentally test methods of mode transition, a Combined Cycle Engine (CCE) Large-scale Inlet testbed was designed with two flow paths-a low speed flow-path sized for a turbine cycle and a high speed flow-path designed for a DMSJ. This testbed system is identified as the CCE Large-Scale Inlet for Mode Transition studies (CCE-LIMX). The test plan for the CCE-LIMX in the NASA Glenn Research Center (GRC) 10- by 10-ft Supersonic Wind Tunnel (10x10 SWT) is segmented into multiple phases. The first phase is a matrix of inlet characterization (IC) tests to evaluate the inlet performance and establish the mode transition schedule. The second phase is a matrix of dynamic system identification (SysID) experiments designed to support closed-loop control development at mode transition schedule operating points for the CCE-LIMX. The third phase includes a direct demonstration of controlled mode transition using a closed loop control

  11. Performance investigation of a novel water–power cogeneration plant (WPCP) based on humidification dehumidification (HDH) method

    International Nuclear Information System (INIS)

    He, W.F.; Han, D.; Xu, L.N.; Yue, C.; Pu, W.H.

    2016-01-01

    Highlights: • A novel water–power cogeneration plant (WPCP) is proposed. • Energy analysis of the proposed WPCP is achieved. • Comparison of the WPCP performance at different pressures is fulfilled. • Performance correlation between the HDH desalination and ORC power subsystems is revealed. - Abstract: Humidification dehumidification (HDH) technology was well applied to produce freshwater in the desalination system. However, besides the demand of freshwater, power is also required simultaneously in most situations. In the paper, a novel water–power cogeneration plant (WPCP) based on the HDH desalination system coupled with the organic Rankine cycle (ORC) is proposed. Energy analysis for the proposed combined system at different appointed operation parameters is achieved, and the corresponding performance correlation between the HDH desalination and ORC power system are revealed. It is verified that the production of freshwater and electricity can be gained synchronously in the suggested novel platform, and the performance of the whole system is really sensitive to the operation parameters of the HDH desalination system. It is found that after the regulation of the operation pressure, p, and the seawater temperature at the outlet of the seawater heater, T sw,2 , for the HDH desalination from p = 0.1 MPa, T sw,2 = 353.15 K to p = 0.3 MPa, T sw,2 = 383.15 K, a maximum elevation, 25.46 kg h −1 for the freshwater production, 4.17 kW for the electricity and 2% for the extended gained output ratio (EGOR) is obtained. Furthermore, owing to the asynchronism between the specific production and the final energy utilization efficiency, the balance should be optimized among the demand of the freshwater and power and the efficiency of the novel WPCP.

  12. Low CO2-emissions hybrid solar combined-cycle power system with methane membrane reforming

    International Nuclear Information System (INIS)

    Li, Yuanyuan; Zhang, Na; Cai, Ruixian

    2013-01-01

    Based on the principle of cascade utilization of multiple energy resources, a gas-steam combined cycle power system integrated with solar thermo-chemical fuel conversion and CO 2 capture has been proposed and analyzed. The collected solar heat at 550 °C drives the endothermic methane reforming and is converted to the produced syngas chemical exergy, and then released as high-temperature thermal energy via combustion for power generation, achieving its high-efficiency heat-power conversion. The reforming reaction is integrated with a hydrogen separation membrane, which continuously withdraws hydrogen from the reaction zone and enables nearly full methane conversion. The CO 2 enriched gas being concentrated in the retentate zone is collected and processed with pre-combustion decarbonization. The system is thermodynamically simulated using the ASPEN PLUS code. The results show that with 91% CO 2 captured, the specific CO 2 emission is 25 g/kWh. An exergy efficiency of 58% and thermal efficiency of 51.6% can be obtained. A fossil fuel saving ratio of 31.2% is achievable with a solar thermal share of 28.2%, and the net solar-to-electricity efficiency based on the gross solar heat incident on the collector is about 36.4% compared with the same gas-steam combined cycle system with an equal CO 2 removal ratio obtained by post-combustion decarbonization. - Highlights: ► A solar-assisted hybrid combined cycle power system has been proposed and analyzed. ► The system integrates power generation with solar-driven reforming and CO 2 capture. ► solar heat upgrading and high-efficiency heat-to-power conversion are achieved. ► membrane reforming enables high CH 4 conversion and pre-combustion CO 2 capture. ► The system thermodynamic performances have been investigated and compared

  13. Computational Fluid Dynamics Analysis Method Developed for Rocket-Based Combined Cycle Engine Inlet

    Science.gov (United States)

    1997-01-01

    Renewed interest in hypersonic propulsion systems has led to research programs investigating combined cycle engines that are designed to operate efficiently across the flight regime. The Rocket-Based Combined Cycle Engine is a propulsion system under development at the NASA Lewis Research Center. This engine integrates a high specific impulse, low thrust-to-weight, airbreathing engine with a low-impulse, high thrust-to-weight rocket. From takeoff to Mach 2.5, the engine operates as an air-augmented rocket. At Mach 2.5, the engine becomes a dual-mode ramjet; and beyond Mach 8, the rocket is turned back on. One Rocket-Based Combined Cycle Engine variation known as the "Strut-Jet" concept is being investigated jointly by NASA Lewis, the U.S. Air Force, Gencorp Aerojet, General Applied Science Labs (GASL), and Lockheed Martin Corporation. Work thus far has included wind tunnel experiments and computational fluid dynamics (CFD) investigations with the NPARC code. The CFD method was initiated by modeling the geometry of the Strut-Jet with the GRIDGEN structured grid generator. Grids representing a subscale inlet model and the full-scale demonstrator geometry were constructed. These grids modeled one-half of the symmetric inlet flow path, including the precompression plate, diverter, center duct, side duct, and combustor. After the grid generation, full Navier-Stokes flow simulations were conducted with the NPARC Navier-Stokes code. The Chien low-Reynolds-number k-e turbulence model was employed to simulate the high-speed turbulent flow. Finally, the CFD solutions were postprocessed with a Fortran code. This code provided wall static pressure distributions, pitot pressure distributions, mass flow rates, and internal drag. These results were compared with experimental data from a subscale inlet test for code validation; then they were used to help evaluate the demonstrator engine net thrust.

  14. Integrated gasification gas combined cycle plant with membrane reactors: Technological and economical analysis

    International Nuclear Information System (INIS)

    Amelio, Mario; Morrone, Pietropaolo; Gallucci, Fausto; Basile, Angelo

    2007-01-01

    In the present work, the capture and storage of carbon dioxide from the fossil fuel power plant have been considered. The main objective was to analyze the thermodynamic performances and the technological aspects of two integrated gasification gas combined cycle plants (IGCC), as well as to give a forecast of the investment costs for the plants and the resulting energy consumptions. The first plant considered is an IGCC* plant (integrated gasification gas combined cycle plant with traditional shift reactors) characterized by the traditional water gas shift reactors and a CO 2 physical adsorption system followed by the power section. The second one is an IGCC M plant (integrated gasification gas combined cycle plant with membrane reactor) where the coal thermal input is the same as the first one, but the traditional shift reactors and the physical adsorption unit are replaced by catalytic palladium membrane reactors (CMR). In the present work, a mono-dimensional computational model of the membrane reactor was proposed to simulate and evaluate the capability of the IGCC M plant to capture carbon dioxide. The energetic performances, efficiency and net power of the IGCC* and IGCC M plants were, thus, compared, assuming as standard a traditional IGCC plant without carbon dioxide capture. The economical aspects of the three plants were compared through an economical analysis. Since the IGCC* and IGCC M plants have additional costs related to the capture and disposal of the carbon dioxide, a Carbon Tax (adopted in some countries like Sweden) proportional to the number of kilograms of carbon dioxide released in the environment was assumed. According to the economical analysis, the IGCC M plant proved to be more convenient than the IGCC* one

  15. Techno-economic assessment and optimization of stirling engine micro-cogeneration systems in residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Alanne, Kari; Soederholm, Niklas; Siren, Kai [Dept. of Energy Technology, Helsinki University of Technology, P.O. Box 4100, 02015 TKK (Finland); Beausoleil-Morrison, Ian [Dept. of Mechanical and Aerospace Engineering, Carleton University, Ottawa (Canada)

    2010-12-15

    Micro-cogeneration offers numerous potential advantages for the supply of energy to residential buildings in the sense of improved energy efficiency and reduced environmental burdens. To realize these benefits, however, such systems must reduce energy costs, primary energy consumption, and CO{sub 2} emissions relative to conventional heating systems. In this paper, we search for optimized strategies for the integration of a Stirling engine-based micro-cogeneration system in residential buildings by comparing the performance of various system configurations and operational strategies with that of a reference system, i.e. hydronic heating and a low temperature gas boiler in standard and passive house constructions located in different climates. The IDA-ICE whole-building simulation program is employed with the Stirling engine micro-cogeneration model that was developed by IEA/ECBCS Annex 42. In this way the dynamic effects of micro-cogeneration devices, such as warm-ups and shutdowns, are accounted for. This study contributes to the research by addressing hourly changes in the fuel mix used for central electricity generation and the utilization of thermal exhaust through heat recovery. Our results suggest that an optimally operated micro-cogeneration system encompassing heat recovery and appropriate thermal storage would result in a 3-5% decrease in primary energy consumption and CO{sub 2} emissions when compared to a conventional hydronic heating system. Moreover, this configuration is capable of delivering annual savings in all the combinations of electricity and fuel price between 0.05 and 0.15 EUR kW h{sup -1}. As can be expected, these results are sensitive to the electrical energy supply mix, building type, and climate. (author)

  16. Techno-economic assessment and optimization of Stirling engine micro-cogeneration systems in residential buildings

    International Nuclear Information System (INIS)

    Alanne, Kari; Soederholm, Niklas; Siren, Kai; Beausoleil-Morrison, Ian

    2010-01-01

    Micro-cogeneration offers numerous potential advantages for the supply of energy to residential buildings in the sense of improved energy efficiency and reduced environmental burdens. To realize these benefits, however, such systems must reduce energy costs, primary energy consumption, and CO 2 emissions relative to conventional heating systems. In this paper, we search for optimized strategies for the integration of a Stirling engine-based micro-cogeneration system in residential buildings by comparing the performance of various system configurations and operational strategies with that of a reference system, i.e. hydronic heating and a low temperature gas boiler in standard and passive house constructions located in different climates. The IDA-ICE whole-building simulation program is employed with the Stirling engine micro-cogeneration model that was developed by IEA/ECBCS Annex 42. In this way the dynamic effects of micro-cogeneration devices, such as warm-ups and shutdowns, are accounted for. This study contributes to the research by addressing hourly changes in the fuel mix used for central electricity generation and the utilization of thermal exhaust through heat recovery. Our results suggest that an optimally operated micro-cogeneration system encompassing heat recovery and appropriate thermal storage would result in a 3-5% decrease in primary energy consumption and CO 2 emissions when compared to a conventional hydronic heating system. Moreover, this configuration is capable of delivering annual savings in all the combinations of electricity and fuel price between 0.05 and 0.15 Euro kW h -1 . As can be expected, these results are sensitive to the electrical energy supply mix, building type, and climate.

  17. Efficiency analysis of a cogeneration and district energy system

    International Nuclear Information System (INIS)

    Rosen, Marc A.; Le, Minh N.; Dincer, Ibrahim

    2005-01-01

    This paper presents an efficiency analysis, accounting for both energy and exergy considerations, of a design for a cogeneration-based district energy system. A case study is considered for the city of Edmonton, Canada, by the utility Edmonton Power. The original concept using central electric chillers, as well as two variations (one considering single-effect and the other double-effect absorption chillers) are examined. The energy- and exergy-based results differ markedly (e.g., overall energy efficiencies are shown to vary for the three configurations considered from 83% to 94%, and exergy efficiencies from 28% to 29%, respectively). For the overall processes, as well as individual subprocesses and selected combinations of subprocesses, the exergy efficiencies are generally found to be more meaningful and indicative of system behaviour than the energy efficiencies

  18. Production costs: U.S. gas turbine ampersand combined-cycle power plants

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This fourth edition of UDI's gas turbine O ampersand M cost report gives 1991 operation and maintenance expenses for over 450 US gas turbine power plants. Modeled on UDI's popular series of O ampersand M cost reports for US steam-electric plants, this report shows operator and plant name, plant year-in-service, installed capacity, 1991 net generation, total fuel expenses, total non-fuel O ampersand M expenses, total production costs, and current plant capitalization. Coverage includes over 90 percent of the utility-owned gas/combustion turbine and combined-cycle plants installed in the country

  19. Multidisciplinary design of a rocket-based combined cycle SSTO launch vehicle using Taguchi methods

    Science.gov (United States)

    Olds, John R.; Walberg, Gerald D.

    1993-01-01

    Results are presented from the optimization process of a winged-cone configuration SSTO launch vehicle that employs a rocket-based ejector/ramjet/scramjet/rocket operational mode variable-cycle engine. The Taguchi multidisciplinary parametric-design method was used to evaluate the effects of simultaneously changing a total of eight design variables, rather than changing them one at a time as in conventional tradeoff studies. A combination of design variables was in this way identified which yields very attractive vehicle dry and gross weights.

  20. Turbulent Mixing of Primary and Secondary Flow Streams in a Rocket-Based Combined Cycle Engine

    Science.gov (United States)

    Cramer, J. M.; Greene, M. U.; Pal, S.; Santoro, R. J.; Turner, Jim (Technical Monitor)

    2002-01-01

    This viewgraph presentation gives an overview of the turbulent mixing of primary and secondary flow streams in a rocket-based combined cycle (RBCC) engine. A significant RBCC ejector mode database has been generated, detailing single and twin thruster configurations and global and local measurements. On-going analysis and correlation efforts include Marshall Space Flight Center computational fluid dynamics modeling and turbulent shear layer analysis. Potential follow-on activities include detailed measurements of air flow static pressure and velocity profiles, investigations into other thruster spacing configurations, performing a fundamental shear layer mixing study, and demonstrating single-shot Raman measurements.

  1. The combination of an Environmental Management System and Life Cycle Assessment at the territorial level

    Energy Technology Data Exchange (ETDEWEB)

    Mazzi, Anna; Toniolo, Sara; Catto, Stella; De Lorenzi, Valentina; Scipioni, Antonio, E-mail: scipioni@unipd.it

    2017-03-15

    A framework to include a Life Cycle Assessment in the significance evaluation of the environmental aspects of an Environmental Management System has been studied for some industrial sectors, but there is a literature gap at the territorial level, where the indirect impact assessment is crucial. To overcome this criticality, our research proposes the Life Cycle Assessment as a framework to assess environmental aspects of public administration within an Environmental Management System applied at the territorial level. This research is structured in two parts: the design of a new methodological framework and the pilot application for an Italian municipality. The methodological framework designed supports Initial Environmental Analysis at the territorial level thanks to the results derived from the impact assessment phase. The pilot application in an Italian municipality EMAS registered demonstrates the applicability of the framework and its effectiveness in evaluating the environmental impact assessment for direct and indirect aspects. Through the discussion of the results, we underline the growing knowledge derived by this research in terms of the reproducibility and consistency of the criteria to define the significance of the direct and indirect environmental aspects for a local public administration. - Highlights: • The combination between Environmental Management System and LCA is studied. • A methodological framework is elaborated and tested at the territorial level. • Life Cycle Impact Assessment supports the evaluation of aspects significance. • The framework assures consistency of evaluation criteria on the studied territory.

  2. The combination of an Environmental Management System and Life Cycle Assessment at the territorial level

    International Nuclear Information System (INIS)

    Mazzi, Anna; Toniolo, Sara; Catto, Stella; De Lorenzi, Valentina; Scipioni, Antonio

    2017-01-01

    A framework to include a Life Cycle Assessment in the significance evaluation of the environmental aspects of an Environmental Management System has been studied for some industrial sectors, but there is a literature gap at the territorial level, where the indirect impact assessment is crucial. To overcome this criticality, our research proposes the Life Cycle Assessment as a framework to assess environmental aspects of public administration within an Environmental Management System applied at the territorial level. This research is structured in two parts: the design of a new methodological framework and the pilot application for an Italian municipality. The methodological framework designed supports Initial Environmental Analysis at the territorial level thanks to the results derived from the impact assessment phase. The pilot application in an Italian municipality EMAS registered demonstrates the applicability of the framework and its effectiveness in evaluating the environmental impact assessment for direct and indirect aspects. Through the discussion of the results, we underline the growing knowledge derived by this research in terms of the reproducibility and consistency of the criteria to define the significance of the direct and indirect environmental aspects for a local public administration. - Highlights: • The combination between Environmental Management System and LCA is studied. • A methodological framework is elaborated and tested at the territorial level. • Life Cycle Impact Assessment supports the evaluation of aspects significance. • The framework assures consistency of evaluation criteria on the studied territory.

  3. Exergetic Analysis of a Novel Solar Cooling System for Combined Cycle Power Plants

    Directory of Open Access Journals (Sweden)

    Francesco Calise

    2016-09-01

    Full Text Available This paper presents a detailed exergetic analysis of a novel high-temperature Solar Assisted Combined Cycle (SACC power plant. The system includes a solar field consisting of innovative high-temperature flat plate evacuated solar thermal collectors, a double stage LiBr-H2O absorption chiller, pumps, heat exchangers, storage tanks, mixers, diverters, controllers and a simple single-pressure Combined Cycle (CC power plant. Here, a high temperature solar cooling system is coupled with a conventional combined cycle, in order to pre-cool gas turbine inlet air in order to enhance system efficiency and electrical capacity. In this paper, the system is analyzed from an exergetic point of view, on the basis of an energy-economic model presented in a recent work, where the obtained main results show that SACC exhibits a higher electrical production and efficiency with respect to the conventional CC. The system performance is evaluated by a dynamic simulation, where detailed simulation models are implemented for all the components included in the system. In addition, for all the components and for the system as whole, energy and exergy balances are implemented in order to calculate the magnitude of the irreversibilities within the system. In fact, exergy analysis is used in order to assess: exergy destructions and exergetic efficiencies. Such parameters are used in order to evaluate the magnitude of the irreversibilities in the system and to identify the sources of such irreversibilities. Exergetic efficiencies and exergy destructions are dynamically calculated for the 1-year operation of the system. Similarly, exergetic results are also integrated on weekly and yearly bases in order to evaluate the corresponding irreversibilities. The results showed that the components of the Joule cycle (combustor, turbine and compressor are the major sources of irreversibilities. System overall exergetic efficiency was around 48%. Average weekly solar collector

  4. Performance Analysis of Solar Combined Ejector-Vapor Compression Cycle Using Environmental Friendly Refrigerants

    Directory of Open Access Journals (Sweden)

    A. B. Kasaeian

    2013-04-01

    Full Text Available In this study, a new model of a solar combined ejector-vapor compression refrigeration system has been considered. The system is equipped with an internal heat exchanger to enhance the performance of the cycle. The effects of working fluid and operating conditions on the system performance including COP, entrainment ratio (ω, compression ratio (rp and exergy efficiency were investigated. Some working fluids suggested are: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e and R1234ze(z. The results show that R114 and R1234ze(e yield the highest COP and exergy efficiency followed by R123, R245fa, R365mfc, R141b, R152a and R600a. It is noticed that the COP value of the new solar ejector-vapor compression refrigeration cycle is higher than that of the conventional ejector cycle with R1234ze(e for all operating conditions. This paper also demonstrates that R1234ze(e will be a suitable refrigerant in the solar combined ejector-vapor compression refrigeration system, due to its environmental friendly properties and better performance. ABSTRAK: Kajian ini menganalisa model baru sistem penyejukan mampatan gabungan ejektor-wap solar.Sistem ini dilengkapi dengan penukar haba dalaman untuk meningkatkan prestasi kitaran.Kesan bendalir bekerja dan keadaan operasi pada prestasi sistem termasuk COP, nisbah pemerangkapan (ω, nisbah mampatan (rp dan kecekapan eksergi telah disiasat.Beberapa bendalir bekerja yang dicadangkan adalah: R114, R141b, R123, R245fa, R600a, R365mfc, R1234ze(e dan R1234ze(z.Hasil kajian menunjukkan R114 dan R1234ze(e menghasilkan COP dan kecekapan eksergi tertinggi diikuti oleh R123, R245fa, R365mfc, R141b, R152a dan R600a.Didapati nilai COP kitaran penyejukan mampatan bagi ejektor-wap solar baru adalah lebih tinggi daripada kitaran ejektor konvensional dengan R1234ze(e bagi semua keadaan operasi.Kertas kerja ini juga menunjukkan bahawa R1234ze(e boleh menjadi penyejuk yang sesuai dalam sistem penyejukan mampatan gabungan ejektor

  5. Combined cycles, impacts of technological requirements; Ciclos combinados, impactos de requerimientos tecnologicos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Santalo, Jose Miguel [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    The fundamental growth of the Mexican electrical sector for the next ten years is planned on base of the installation of 20 thousand Mw plants of combined cycle. This article presents an analysis of the impact of these power stations finding out that the power stations of combined cycle are at the moment cheaper - from 600 to 700 dollars by installed kW- than the alternative coal options or fuel oil, that are in the range of 900 to 1200 dollars per kW, in addition to which the time required for their construction is shorter. [Spanish] El crecimiento fundamental del sector electrico mexicano para los proximos diez anos esta planeado con base en la instalacion de 20 mil Mw de plantas de ciclo combinado. Este articulo presenta un analisis del impacto de dichas centrales encontrando que las centrales de ciclo combinado actualmente resultan mas baratas - de 600 a 700 dolares por kW instalado - que las opciones alternativas de carbon o combustoleo que estan en el rango de 900 a 1200 dolares por kW, ademas de que los tiempos requeridos para su construccion son menores.

  6. Thermoeconomic optimization of a combined-cycle solar tower power plant

    International Nuclear Information System (INIS)

    Spelling, James; Favrat, Daniel; Martin, Andrew; Augsburger, Germain

    2012-01-01

    A dynamic model of a pure-solar combined-cycle power plant has been developed in order to allow determination of the thermodynamic and economic performance of the plant for a variety of operating conditions and superstructure layouts. The model was then used for multi-objective thermoeconomic optimization of both the power plant performance and cost, using a population-based evolutionary algorithm. In order to examine the trade-offs that must be made, two conflicting objectives will be considered, namely minimal investment costs and minimal levelized electricity costs. It was shown that efficiencies in the region of 18–24% can be achieved, and this for levelized electricity costs in the region of 12–24 UScts/kWh e , depending on the magnitude of the initial investment, making the system competitive with current solar thermal technology. -- Highlights: ► Pure-solar combined-cycle studied using thermoeconomic tools. ► Multi-objective optimization conducted to determine Pareto-optimal power plant designs. ► Levelised costs between 12 and 24 UScts/kWhe predicted. ► Efficiencies between 18 and 24% predicted.

  7. Unsteady flow characteristic analysis of turbine based combined cycle (TBCC inlet mode transition

    Directory of Open Access Journals (Sweden)

    Jun Liu

    2015-09-01

    Full Text Available A turbine based combined cycle (TBCC propulsion system uses a turbine-based engine to accelerate the vehicle from takeoff to the mode transition flight condition, at which point, the propulsion system performs a “mode transition” from the turbine to ramjet engine. Smooth inlet mode transition is accomplished when flow is diverted from one flowpath to the other, without experiencing unstart or buzz. The smooth inlet mode transition is a complex unsteady process and it is one of the enabling technologies for combined cycle engine to become a functional reality. In order to unveil the unsteady process of inlet mode transition, the research of over/under TBCC inlet mode transition was conducted through a numerical simulation. It shows that during the mode transition the terminal shock oscillates in the inlet. During the process of inlet mode transition mass flow rate and Mach number of turbojet flowpath reduce with oscillation. While in ramjet flowpath the flow field is non-uniform at the beginning of inlet mode transition. The speed of mode transition and the operation states of the turbojet and ramjet engines will affect the motion of terminal shock. The result obtained in present paper can help us realize the unsteady flow characteristic during the mode transition and provide some suggestions for TBCC inlet mode transition based on the smooth transition of thrust.

  8. Optimization of controlled processes in combined-cycle plant (new developments and researches)

    Science.gov (United States)

    Tverskoy, Yu S.; Muravev, I. K.

    2017-11-01

    All modern complex technical systems, including power units of TPP and nuclear power plants, work in the system-forming structure of multifunctional APCS. The development of the modern APCS mathematical support allows bringing the automation degree to the solution of complex optimization problems of equipment heat-mass-exchange processes in real time. The difficulty of efficient management of a binary power unit is related to the need to solve jointly at least three problems. The first problem is related to the physical issues of combined-cycle technologies. The second problem is determined by the criticality of the CCGT operation to changes in the regime and climatic factors. The third problem is related to a precise description of a vector of controlled coordinates of a complex technological object. To obtain a joint solution of this complex of interconnected problems, the methodology of generalized thermodynamic analysis, methods of the theory of automatic control and mathematical modeling are used. In the present report, results of new developments and studies are shown. These results allow improving the principles of process control and the automatic control systems structural synthesis of power units with combined-cycle plants that provide attainable technical and economic efficiency and operational reliability of equipment.

  9. Municipal solid wastes incineration with combined cycle: a case study from Sao Paulo

    Energy Technology Data Exchange (ETDEWEB)

    Cerda Balcazar, Juan Galvarino; Dias, Rubens Alves; Balestieri, Jose Antonio Perrella [Universidade Estadual Paulista (UNESP), Guaratingueta, SP (Brazil)], E-mails: pos09007@feg.unesp.br, rubdias@feg.unesp.br

    2010-07-01

    Large urban centers have a huge demand for electricity, for the needs of its residents, and a growing problem of management of solid waste generated by it, that becomes an public administrative and great social problem. The correct disposal of solid waste generated by large urban centers is now one of the most complex engineering problems involving logistics, safety, environment, energy spent among other tools for sound management of municipal solid waste (MSW). This study was carried out a study of the use of incinerators and residue derived fuel and MSW with combined cycles, with the aim of producing thermal and mechanical energy (this later becomes electrical energy) and solid waste treatment in Sao Paulo. We used existing models and real plants in the European Union in this case, with the aim of making it the most viable and compatible with the current context of energy planning and resource today. A technical and economic feasibility study for a plant of this nature, using the scheme, is presented. It is expected a good attractiveness of using incinerators combined-cycle, due to its high efficiency and its ability to thermoelectric generation. (author)

  10. Prospective gas turbine and combined-cycle units for power engineering (a Review)

    Science.gov (United States)

    Ol'khovskii, G. G.

    2013-02-01

    The modern state of technology for making gas turbines around the world and heat-recovery combined-cycle units constructed on their basis are considered. The progress achieved in this field by Siemens, Mitsubishi, General Electric, and Alstom is analyzed, and the objectives these companies set forth for themselves for the near and more distant future are discussed. The 375-MW gas turbine unit with an efficiency of 40% produced by Siemens, which is presently the largest one, is subjected to a detailed analysis. The main specific features of this turbine are that the gas turbine unit's hot-path components have purely air cooling, due to which the installation has enhanced maneuverability. The single-shaft combined-cycle plant constructed on the basis of this turbine has a capacity of 570 MW and efficiency higher than 60%. Programs adopted by different companies for development of new-generation gas turbine units firing synthesis gas and fitted with low-emission combustion chambers and new cooling systems are considered. Concepts of rotor blades for new gas turbine units with improved thermal barrier coatings and composite blades different parts of which are made of materials selected in accordance with the conditions of their operation are discussed.

  11. Modelling and optimization of combined cycle power plant based on exergoeconomic and environmental analyses

    International Nuclear Information System (INIS)

    Ganjehkaviri, A.; Mohd Jaafar, M.N.; Ahmadi, P.; Barzegaravval, H.

    2014-01-01

    This research paper presents a study on a comprehensive thermodynamic modelling of a combined cycle power plant (CCPP). The effects of economic strategies and design parameters on the plant optimization are also studied. Exergoeconomic analysis is conducted in order to determine the cost of electricity and cost of exergy destruction. In addition, a comprehensive optimization study is performed to determine the optimal design parameters of the power plant. Next, the effects of economic parameters variations on the sustainability, carbon dioxide emission and fuel consumption of the plant are investigated and are presented for a typical combined cycle power plant. Therefore, the changes in economic parameters caused the balance between cash flows and fix costs of the plant changes at optimum point. Moreover, economic strategies greatly limited the maximum reasonable carbon emission and fuel consumption reduction. The results showed that by using the optimum values, the exergy efficiency increases for about 6%, while CO 2 emission decreases by 5.63%. However, the variation in the cost was less than 1% due to the fact that a cost constraint was implemented. In addition, the sensitivity analysis for the optimization study was curtailed to be carried out; therefore, the optimization process and results to two important parameters are presented and discussed.

  12. Effective energy management by combining gas turbine cycles and forward osmosis desalination process

    International Nuclear Information System (INIS)

    Park, Min Young; Shin, Serin; Kim, Eung Soo

    2015-01-01

    Highlights: • Innovative gas turbine system and FO integrated system was proposed. • The feasibility of the integrated system was analyzed thermodynamically. • GOR of the FO–gas turbine system is 17% higher than those of MED and MSF. • Waste heat utilization of the suggested system is 85.7%. • Water production capacity of the suggested system is 3.5 times higher than the MSF–gas turbine system. - Abstract: In the recent years, attempts to improve the thermal efficiency of the gas turbine cycles have been made. In order to enhance the energy management of the gas turbine cycle, a new integration concept has been proposed; integration of gas turbine cycle and forward osmosis desalination process. The combination of the gas turbine cycle and the forward osmosis (FO) desalination process basically implies the coupling of the waste heat from the gas turbine cycle to the draw solute recovery system in the FO process which is the most energy consuming part of the whole FO process. By doing this, a strong system that is capable of producing water and electricity with very little waste heat can be achieved. The feasibility of this newly proposed system was analyzed using UNISIM program and the OLI property package. For the analysis, the thermolytic draw solutes which has been suggested by other research groups have been selected and studied. Sensitivity analysis was conducted on the integration system in order to understand and identify the key parameters of the integrated system. And the integrated system was further evaluated by comparing the gain output ratio (GOR) values with the conventional desalination technologies such as multi stage flash (MSF) and multi effect distillation (MED). The suggested integrated system was calculated to have a GOR of 14.8, while the MSF and MED when integrated to the gas turbine cycle showed GOR value of 12. It should also be noted that the energy utilization of the suggested integrated system is significantly higher by 27

  13. Micro-size cogeneration plants and virtual power plants. New energy landscapes; Mikro-KWK und virtuelle Kraftwerke. Neue Energielandschaften

    Energy Technology Data Exchange (ETDEWEB)

    Roon, Serafin von [Forschungsstelle fuer Energiewirtschaft e.V., Muenchen (Germany)

    2009-07-01

    Combined heat and power generation is an established technology. With micro-size cogeneration units, the technology is now available to private single or multiple dwellings and for decentral power supply of residential blocks. With the right political boundary conditions and integrated into virtual power stations, this is an option for enhanced use of renewable energy sources and for decentral, flexible and climate-friendly heat and power generation in buildings. Economic efficiency analyses by experts, high utilisation rates, innovative developments of the manufacturers and a positive public image are all in favour of a great future for micro-size cogeneration units. (orig.)

  14. Fitting in of cogeneration into central heating systems; Inpassing warmte/kracht in cv-systemen

    Energy Technology Data Exchange (ETDEWEB)

    Rulkens, L.J.W. [FD-Bouwzaken, Ministerie van Landbouw, Natuurbeheer en Visserij LNV, Wageningen (Netherlands); Tijs, J.C. [Tijs Energy Systems, Wijk bij Duurstede (Netherlands); Wammes, J.A. [Emicon, Veenendaal (Netherlands)

    1997-02-01

    The choice for the size of a combined heat and power generating unit as well as the hydraulic and control engineering fitting in into existing central heating systems bears some pitfalls in practice. Those problems are inventorized and compiled for the manual `Design rules for the fitting in of cogeneration into central heating systems`. A brief overview is given of the contents of the manual. 3 figs., 3 ills., 1 tab.

  15. Evaluating the role of cogeneration for carbon management in Alberta

    International Nuclear Information System (INIS)

    Doluweera, G.H.; Jordaan, S.M.; Moore, M.C.; Keith, D.W.; Bergerson, J.A.

    2011-01-01

    Developing long-term carbon control strategies is important in energy intensive industries such as the oil sands operations in Alberta. We examine the use of cogeneration to satisfy the energy demands of oil sands operations in Alberta in the context of carbon management. This paper evaluates the role of cogeneration in meeting Provincial carbon management goals and discusses the arbitrary characteristics of facility- and product-based carbon emissions control regulations. We model an oil sands operation that operates with and without incorporated cogeneration. We compare CO 2 emissions and associated costs under different carbon emissions control regulations, including the present carbon emissions control regulation of Alberta. The results suggest that incorporating cogeneration into the growing oil sands industry could contribute in the near-term to reducing CO 2 emissions in Alberta. This analysis also shows that the different accounting methods and calculations of electricity offsets could lead to very different levels of incentives for cogeneration. Regulations that attempt to manage emissions on a product and facility basis may become arbitrary and complex as regulators attempt to approximate the effect of an economy-wide carbon price. - Highlights: ► We assess the effectiveness of cogeneration for carbon management in Alberta. ► Cogeneration can offset a significant portion of Alberta's high carbon electricity. ► CO 2 reduction potential of cogeneration may be higher if installed immediately. ► Product based policies should approximate the effect of an economy-wide policy.

  16. Economic competitiveness of small modular reactors versus coal and combined cycle plants

    International Nuclear Information System (INIS)

    Alonso, Gustavo; Bilbao, Sama; Valle, Edmundo del

    2016-01-01

    Small modular reactors (SMRs) may be an option to cover the electricity needs of isolated regions, distributed generation grids and countries with small electrical grids. Previous analyses show that the overnight capital cost for SMRs is between 4500 US$/kW and 5350 US$/kW, which is between a 6% and a 26% higher than the average cost of a current large nuclear reactor. This study analyzes the economic competitiveness of small modular reactors against thermal plants using coal and natural gas combined cycle plants. To assess the economic competitiveness of SMRs, three overnight capital costs are considered 4500 US$/kW, 5000 US$/kW and 5350 US$/kW along with three discount rates for each overnight cost considered, these are 3, 7, and 10%. To compare with natural gas combined cycle (CC) units, four different gas prices are considered, these are 4.74 US$/GJ (5 US$/mmBTU), 9.48 US$/GJ (10 US$/mmBTU), 14.22 US$/GJ (15 US$/mmBTU), and 18.96 US$/GJ (20 US$/mmBTU). To compare against coal, two different coal prices are considered 80 and 120 US$/ton of coal. The carbon tax considered, for both CC and coal, is 30 US$/ton CO_2. The results show what scenarios make SMRs competitive against coal and/or combined cycle plants. In addition, because the price of electricity is a key component to guarantee the feasibility of a new project, this analysis calculates the price of electricity for the economically viable deployment of SMRs in all the above scenarios. In particular, this study shows that a minimum price of electricity of 175 US$/MWh is needed to guarantee the feasibility of a new SMR, if its overnight capital cost is 5350 US$/kWe and the discount rate is 10%. Another result is that when the price of electricity is around 100 US$/MWh then the discount rate must be around 7% or less to provide appropriate financial conditions to make SMRs economically feasible. - Highlights: • Small modular reactor (SMR) are economically assessed. • SMR are compared against gas and coal

  17. Thermodynamic performance analysis of a combined power cycle using low grade heat source and LNG cold energy

    International Nuclear Information System (INIS)

    Kim, Kyoung Hoon; Kim, Kyung Chun

    2014-01-01

    Thermodynamic analysis of a combined cycle using a low grade heat source and LNG cold energy was carried out. The combined cycle consisted of an ammonia–water Rankine cycle with and without regeneration and a LNG Rankine cycle. A parametric study was conducted to examine the effects of the key parameters, such as ammonia mass fraction, turbine inlet pressure, condensation temperature. The effects of the ammonia mass fraction on the temperature distributions of the hot and cold streams in heat exchangers were also investigated. The characteristic diagram of the exergy efficiency and heat transfer capability was proposed to consider the system performance and expenditure of the heat exchangers simultaneously. The simulation showed that the system performance is influenced significantly by the parameters with the ammonia mass fraction having largest effect. The net work output of the ammonia–water cycle may have a peak value or increase monotonically with increasing ammonia mass fraction, which depends on turbine inlet pressure or condensation temperature. The exergy efficiency may decrease or increase or have a peak value with turbine inlet pressure depending on the ammonia mass fraction. - Highlights: • Thermodynamic analysis was performed for a combined cycle utilizing LNG cold energy. • Ammonia–water Rankine cycle and LNG Rankine cycle was combined. • A parametric study was conducted to examine the effects of the key parameters. • Characteristics of the exergy efficiency and heat transfer capability were proposed. • The system performance was influenced significantly by the ammonia mass fraction

  18. Cogeneration: a win-win option for Cadbury Nigeria

    International Nuclear Information System (INIS)

    Dayo, Felix; Bogunjoko, S.B.; Sobanwa, A.C.

    2001-01-01

    Like most developing countries, Nigeria is looking to cogeneration as a sustainable and reliable means of overcoming its present unreliable supply of energy. The article focuses on the efforts of the food company Cadbury Nigeria which uses cogeneration for all its steam and power requirements within its own factory. The Company recently decided to upgrade further by switching from liquid fossil fuels to natural gas. Diagrams show the existing system as well as the systems for cogeneration with natural gas. Some of the obstacles to be overcome to improve the viability of cogeneration in developing countries are listed. It is hoped that the outcome of the COP6 meeting to be held in April 2001 will offer encouragement for cogeneration

  19. Cogeneration: a win-win option for Cadbury Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Dayo, Felix [Triple ' E' Systems Associates Ltd. (Nigeria); Bogunjoko, S.B.; Sobanwa, A.C. [Cadbury Nigeria plc. (Nigeria)

    2001-02-01

    Like most developing countries, Nigeria is looking to cogeneration as a sustainable and reliable means of overcoming its present unreliable supply of energy. The article focuses on the efforts of the food company Cadbury Nigeria which uses cogeneration for all its steam and power requirements within its own factory. The Company recently decided to upgrade further by switching from liquid fossil fuels to natural gas. Diagrams show the existing system as well as the systems for cogeneration with natural gas. Some of the obstacles to be overcome to improve the viability of cogeneration in developing countries are listed. It is hoped that the outcome of the COP6 meeting to be held in April 2001 will offer encouragement for cogeneration.

  20. Environmental licensing issues for cogeneration plants

    International Nuclear Information System (INIS)

    Lipka, G.S.; Bibbo, R.V.

    1990-01-01

    The siting and licensing of cogeneration and independent power production (IPP) facilities is a complex process involving a number of interrelated engineering, economic, and environmental impact considerations. Important considerations for the siting and licensing of such facilities include air quality control and air quality impacts, water supply and wastewater disposal, and applicable noise criteria and noise impact considerations. Air quality control and air quality impact considerations for power generation facilities are commonly reviewed in the public forum, and most project developers are generally aware of the key air quality licensing issues. These issues include Best Available Control Technology (BACT) demonstration requirements, and air quality modeling requirements. BACT is a case-by-case determination, which causes uncertainty, in that developers have difficulty in projecting the cost of required control systems. Continuing developments in control technology may cause this problem to continue in the 1990's. Air quality modeling can be a problem in hilly terrain or within or near an urban environment, which could delay or preclude permitting of a new cogeneration or IPP facility in such locations. This paper discusses several environmental issues which are less frequently addressed than air quality issues, namely water/wastewater and noise. The design features of typical cogeneration and IPP facilities that affect water supply requirements, wastewater volumes, and noise emissions are discussed. Then, the site selection and impact review process are examined to identify typical constraints and trade-offs that can develop relative to water, wastewater, and noise issues. Trends in permit review requirements for water, wastewater, and noise are examined. Finally, innovative approaches that can be used to resolve potential development constraints for water, wastewater, and noise issues are discussed

  1. Efficient Use of Cogeneration and Fuel Diversification

    Science.gov (United States)

    Kunickis, M.; Balodis, M.; Sarma, U.; Cers, A.; Linkevics, O.

    2015-12-01

    Energy policy of the European Community is implemented by setting various goals in directives and developing support mechanisms to achieve them. However, very often these policies and legislation come into contradiction with each other, for example Directive 2009/28/EC on the promotion of the use of energy from renewable sources and Directive 2012/27/EU on energy efficiency, repealing Directive 2004/8/EC on the promotion of cogeneration based on a useful heat demand. In this paper, the authors attempt to assess the potential conflicts between policy political objectives to increase the share of high-efficiency co-generation and renewable energy sources (RES), based on the example of Riga district heating system (DHS). If a new heat source using biomass is built on the right bank of Riga DHS to increase the share of RES, the society could overpay for additional heat production capacities, such as a decrease in the loading of existing generating units, thereby contributing to an inefficient use of existing capacity. As a result, the following negative consequences may arise: 1) a decrease in primary energy savings (PES) from high-efficiency cogeneration in Riga DHS, 2) an increase in greenhouse gas (GHG) emissions in the Baltic region, 3) the worsening security situation of electricity supply in the Latvian power system, 4) an increase in the electricity market price in the Lithuanian and Latvian price areas of Nord Pool power exchange. Within the framework of the research, calculations of PES and GHG emission volumes have been performed for the existing situation and for the situation with heat source, using biomass. The effect of construction of biomass heat source on power capacity balances and Nord Pool electricity prices has been evaluated.

  2. Evaluation of ejector performance for an organic Rankine cycle combined power and cooling system

    International Nuclear Information System (INIS)

    Zhang, Kun; Chen, Xue; Markides, Christos N.; Yang, Yong; Shen, Shengqiang

    2016-01-01

    Highlights: • The performance of an ejector in an Organic Rankine Cycle and ejector refrigeration cycle (EORC) was evaluated. • The achieved entrainment ratio and COP of an EORC system is affected significantly by the evaporator conditions (such as temperature, pressure and flow rate). • An optimum distance of 6 mm nozzle position was found that ensures a maximum entrainment ratio, the best efficiency and lowest loss in the ejector. • A reduced total pressure loss between the nozzle inlet and exit leads to a lower energy loss, a higher entrainment ratio and better overall ejector performance. - Abstract: Power-generation systems based on organic Rankine cycles (ORCs) are well suited and increasingly employed in the conversion of thermal energy from low temperature heat sources to power. These systems can be driven by waste heat, for example from various industrial processes, as well as solar or geothermal energy. A useful extension of such systems involves a combined ORC and ejector-refrigeration cycle (EORC) that is capable, at low cost and complexity, of producing useful power while having a simultaneous capacity for cooling that is highly desirable in many applications. A significant thermodynamic loss in such a combined energy system takes place in the ejector due to unavoidable losses caused by irreversible mixing in this component. This paper focuses on the flow and transport processes in an ejector, in order to understand and quantify the underlying reasons for these losses, as well as their sensitivity to important design parameters and operational variables. Specifically, the study considers, beyond variations to the geometric design of the ejector, also the role of changing the external conditions across this component and how these affect its performance; this is not only important in helping develop ejector designs in the first instance, but also in evaluating how the performance may shift (in fact, deteriorate) quantitatively when the device

  3. Total environmental impacts of biofuels from corn stover using a hybrid life cycle assessment model combining process life cycle assessment and economic input-output life cycle assessment.

    Science.gov (United States)

    Liu, Changqi; Huang, Yaji; Wang, Xinye; Tai, Yang; Liu, Lingqin; Liu, Hao

    2018-01-01

    Studies on the environmental analysis of biofuels by fast pyrolysis and hydroprocessing (BFPH) have so far focused only on the environmental impacts from direct emissions and have included few indirect emissions. The influence of ignoring some indirect emissions on the environmental performance of BFPH has not been well investigated and hence is not really understood. In addition, in order to avoid shifting environmental problems from one medium to another, a comprehensive assessment of environmental impacts caused by the processes must quantify the environmental emissions to all media (air, water, and land) in relation to each life cycle stage. A well-to-wheels assessment of the total environmental impacts resulting from direct emissions and indirect emissions of a BFPH system with corn stover is conducted using a hybrid life cycle assessment (LCA) model combining the economic input-output LCA and the process LCA. The Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) has been used to estimate the environmental impacts in terms of acidification, eutrophication, global climate change, ozone depletion, human health criteria, photochemical smog formation, ecotoxicity, human health cancer, and human health noncancer caused by 1 MJ biofuel production. Taking account of all the indirect greenhouse gas (GHG) emissions, the net GHG emissions (81.8 g CO 2 eq/MJ) of the biofuels are still less than those of petroleum-based fuels (94 g CO 2 eq/MJ). Maize production and pyrolysis and hydroprocessing make major contributions to all impact categories except the human health criteria. All impact categories resulting from indirect emissions except eutrophication and smog air make more than 24% contribution to the total environmental impacts. Therefore, the indirect emissions are important and cannot be ignored. Sensitivity analysis has shown that corn stover yield and bio-oil yield affect the total environmental impacts of the biofuels

  4. Preliminary study of nuclear power cogeneration system using gas turbine process

    Energy Technology Data Exchange (ETDEWEB)

    Fumizawa, Motoo; Inaba, Yoshitomo; Hishida, Makoto [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Ogawa, Masuro; Ogata, Kann; Yamada, Seiya

    1995-12-01

    The Nuclear power generation plant (NPGP) releases smaller amount of carbon dioxide than the fossil power plant for the generation of the unit electrical power. Thus, the NPGP is expected to contribute resolving the ecological problems. It is important to investigate the nuclear power cogeneration system using gas turbine process from the view point that it is better to produce electricity in high thermal efficiency from the high temperature energy. We carried out, in the current preliminary study, the survey and selection of the candidate cycles, then conducted the evaluation of cycle efficiency, the selection of R and D items to be solved for the decision of the optimum cycle. Following this, we evaluated nuclear heat application for intermediate and low temperature level released from gas turbine process and overall efficiency of cogeneration system. As a result, it was clarified that overall efficiency of the direct regenerative cycle was the highest in low temperature region below 200degC, and that of the direct regenerative inter cooling cycle was the highest in middle and high temperature region. (author).

  5. Preliminary study of nuclear power cogeneration system using gas turbine process

    International Nuclear Information System (INIS)

    Fumizawa, Motoo; Inaba, Yoshitomo; Hishida, Makoto; Ogawa, Masuro; Ogata, Kann; Yamada, Seiya.

    1995-12-01

    The Nuclear power generation plant (NPGP) releases smaller amount of carbon dioxide than the fossil power plant for the generation of the unit electrical power. Thus, the NPGP is expected to contribute resolving the ecological problems. It is important to investigate the nuclear power cogeneration system using gas turbine process from the view point that it is better to produce electricity in high thermal efficiency from the high temperature energy. We carried out, in the current preliminary study, the survey and selection of the candidate cycles, then conducted the evaluation of cycle efficiency, the selection of R and D items to be solved for the decision of the optimum cycle. Following this, we evaluated nuclear heat application for intermediate and low temperature level released from gas turbine process and overall efficiency of cogeneration system. As a result, it was clarified that overall efficiency of the direct regenerative cycle was the highest in low temperature region below 200degC, and that of the direct regenerative inter cooling cycle was the highest in middle and high temperature region. (author)

  6. A technical analysis for cogeneration systems with potential applications in twelve California industrial plants. [energy saving heat-electricity utility systems

    Science.gov (United States)

    Moretti, V. C.; Davis, H. S.; Slonski, M. L.

    1978-01-01

    In a study sponsored by the State of California Energy Resources Conservation and Development Commission, 12 industrial plants in five utility districts were surveyed to assess the potential applications of the cogeneration of heat and electricity in California industry. Thermodynamic calculations were made for each plant in determining the energy required to meet the existing electrical and steam demands. The present systems were then compared to conceptual cogeneration systems specified for each plant. Overall energy savings were determined for the cogeneration applications. Steam and gas turbine topping cycle systems were considered as well as bottoming cycle systems. Types of industries studied were: pulp and paper, timber, cement, petroleum refining, enhanced oil recovery, foods processing, steel and glass

  7. Implementation of a cogeneration plant for a food processing facility. A case study

    International Nuclear Information System (INIS)

    Bianco, Vincenzo; De Rosa, Mattia; Scarpa, Federico; Tagliafico, Luca A.

    2016-01-01

    Highlights: • CHP utilization is demonstrated to allow a reduction of primary energy consumption. • The consideration of various investment indexes leads to the determination of different optimal powers. • The choice of a specific investment index to evaluate a CHP is linked to the strategy of the company. - Abstract: The present work presents an investigation regarding the feasibility analysis of a cogeneration plant for a food processing facility with the aim to decrease the cost of energy supply. The monthly electricity and heat consumption profiles are analyzed, in order to understand the consumption profiles, as well as the costs of the current furniture of electricity and gas. Then, a detailed thermodynamic model of the cogeneration cycle is implemented and the investment costs are linked to the thermodynamic variables by means of cost functions. The optimal electricity power of the co-generator is determined with reference to various investment indexes. The analysis highlights that the optimal dimension varies according to the chosen indicator, therefore it is not possible to establish it univocally, but it depends on the financial/economic strategy of the company through the considered investment index.

  8. Thermoeconomic evaluation and optimization of a Brayton–Rankine–Kalina combined triple power cycle

    International Nuclear Information System (INIS)

    Singh, Omendra Kumar; Kaushik, S.C.

    2013-01-01

    Highlights: • Combustion chamber performance can improve much by investment in efficient design. • Steam turbine performance would also improve by investment in efficient design. • Minimum total cost rate of plant found at gas cycle pressure ratio of around 14. • Total cost rate decreases significantly by decreasing the inlet air temperature. • Total cost rate decreases a little by increasing the inlet air relative humidity. - Abstract: This paper presents thermoeconomic analysis and optimization of a Brayton–Rankine–Kalina combined triple power cycle using Specific Exergy Costing (SPECO) methodology. Cost-balance and auxiliary equations are formulated for each component and for each node and solved through a MATLAB program to get the average cost per unit exergy at different state points. To evaluate the cost effectiveness of the system, the values of thermoeconomic variables for each component are calculated. Large relative cost difference is observed in the steam turbine, HRSG’s, combustion chambers, compressors, recuperators and ammonia–water evaporator. Therefore, these components require greater attention. The performance of steam turbine, combustion chambers, recuperators and ammonia–water evaporator can be appreciably improved by capital investment into more efficient design due to their low values of exergoeconomic factor. The performance of HRSG’s can be improved only marginally due to slightly higher value of exergoeconomic factor but no such recommendation can be made for the compressors which have a quite high value of exergoeconomic factor. The objective function of the thermoeconomic optimization is the minimization of the total cost rate for the whole plant. Its minimum value is found to occur at a gas cycle pressure ratio of around 14. Decreasing inlet air temperature decreases this objective function parameter significantly while increasing relative humidity causes a small decrease in it

  9. Process modelling and techno-economic analysis of natural gas combined cycle integrated with calcium looping

    Directory of Open Access Journals (Sweden)

    Erans María

    2016-01-01

    Full Text Available Calcium looping (CaL is promising for large-scale CO2 capture in the power generation and industrial sectors due to the cheap sorbent used and the relatively low energy penalties achieved with this process. Because of the high operating temperatures the heat utilisation is a major advantage of the process, since a significant amount of power can be generated from it. However, this increases its complexity and capital costs. Therefore, not only the energy efficiency performance is important for these cycles, but also the capital costs must be taken into account, i.e. techno-economic analyses are required in order to determine which parameters and configurations are optimal to enhance technology viability in different integration scenarios. In this study the integration scenarios of CaL cycles and natural gas combined cycles (NGCC are explored. The process models of the NGCC and CaL capture plant are developed to explore the most promising scenarios for NGCC-CaL integration with regards to efficiency penalties. Two scenarios are analysed in detail, and show that the system with heat recovery steam generator (HRSG before and after the capture plant exhibited better performance of 49.1% efficiency compared with that of 45.7% when only one HRSG is located after the capture plant. However, the techno-economic analyses showed that the more energy efficient case, with two HRSGs, implies relatively higher cost of electricity (COE, 44.1€/MWh, when compared to that of the reference plant system (33.1€/MWh. The predicted cost of CO2 avoided for the case with two HRSGS is 29.3 €/ton CO2.

  10. Evaluation of a combined cycle based on an HCCI (Homogenous Charge Compression Ignition) engine heat recovery employing two organic Rankine cycles

    International Nuclear Information System (INIS)

    Khaljani, M.; Saray, R. Khoshbakhti; Bahlouli, K.

    2016-01-01

    In this work, a combined power cycle which includes a HCCI (Homogenous Charge Compression Ignition) engine and two ORCs (Organic Rankine Cycles) is introduced. In the proposed cycle, the waste heats from the engine cooling water and exhaust gases are utilized to drive the ORCs. A parametric study is conducted to show the effects of decision parameters on the performance and on the total cost rate of cycle. Results of the parametric study reveal that increasing the pinch point temperature difference of evaporator and temperature of the condenser leads to reduction in both exergy efficiency and total cost rate of the bottoming cycle. There is a specific evaporator temperature where exergy efficiency is improved, but the total cost rate of the bottoming cycle is maximized. Also, a multi-objective optimization strategy is performed to achieve the best system design parameters from both thermodynamic and economic aspects. The exergy efficiency and the total cost rate of the system have been considered as objective functions. Optimization results indicate that the exergy efficiency of the cycle increases from 44.96% for the base case to 46.02%. Also, approximately1.3% reduction in the cost criteria is achieved. Results of the multi-objective optimization justify the results obtained through the parametric study and demonstrate that the design parameters of both ORCs have conflict effect on the objective functions. - Highlights: • Two Organic Rankine bottoming cycles are coupled with an HCCI Engine. • Exergetic and Exergo-economic analysis of the bottoming cycle are reported. • The system is optimized using multi-objective genetic algorithm. • Objective functions are exergy efficiency and total cost rate of the system. • The exergy efficiency of the cycle increases from 44.96% to 46.02%.

  11. Promising Direction of Perfection of the Utilization Combine Cycle Gas Turbine Units

    Directory of Open Access Journals (Sweden)

    Gabdullina Albina I.

    2017-01-01

    Full Text Available Issues of improving the efficiency of combined cycle gas turbines (CCGT recovery type have been presented. Efficiency gas turbine plant reaches values of 45 % due to rise in temperature to a gas turbine to 1700 °C. Modern technologies for improving the cooling gas turbine components and reducing the excess air ratio leads to a further increase of the efficiency by 1-2 %. Based on research conducted at the Tomsk Polytechnic University, it shows that the CCGT efficiency can be increased by 2-3 % in the winter time due to the use of organic Rankine cycle, low-boiling substances, and air-cooled condensers (ACC. It is necessary to apply the waste heat recovery with condensation of water vapor from the flue gas, it will enhance the efficiency of the CCGT by 2-3 % to increase the efficiency of the heat recovery steam boiler (HRSB to 10-12 %. Replacing electric pumps gas turbine engine (GTE helps to reduce electricity consumption for auxiliary needs CCGT by 0.5-1.5 %. At the same time the heat of flue gas turbine engine may be useful used in HRSB, thus will increase the capacity and efficiency of the steam turbine.

  12. Thermodynamic analysis of a combined gas turbine, ORC cycle and absorption refrigeration for a CCHP system

    International Nuclear Information System (INIS)

    Mohammadi, Amin; Kasaeian, Alibakhsh; Pourfayaz, Fathollah; Ahmadi, Mohammad Hossein

    2017-01-01

    Highlights: • Thermodynamic analysis of a hybrid CCHP system. • Sensitivity analysis is performed on the most important parameters of the system. • Pressure ratio and gas turbine inlet temperature are the most effective parameters. - Abstract: Hybrid power systems are gained more attention due to their better performance and higher efficiency. Widespread use of these systems improves environmental situation as they reduce the amount of fossil fuel consumption. In this paper a hybrid system composed of a gas turbine, an ORC cycle and an absorption refrigeration cycle is proposed as a combined cooling, heating and power system for residential usage. Thermodynamic analysis is applied on the system. Also a parametric analysis is carried out to investigate the effect of different parameters on the system performance and output cooling, heating and power. The results show that under design conditions, the proposed plant can produce 30 kW power, 8 kW cooling and almost 7.2 ton hot water with an efficiency of 67.6%. Moreover, parametric analysis shows that pressure ratio and gas turbine inlet temperature are the most important and influential parameters. After these two, ORC turbine inlet temperature is the most effective parameter as it can change both net output power and energy efficiency of the system.

  13. A New Superalloy Enabling Heavy Duty Gas Turbine Wheels for Improved Combined Cycle Efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Detor, Andrew [General Electric Company, Niskayuna, NY (United States). GE Global Research; DiDomizio, Richard [General Electric Company, Niskayuna, NY (United States). GE Global Research; McAllister, Don [The Ohio State Univ., Columbus, OH (United States); Sampson, Erica [General Electric Company, Niskayuna, NY (United States). GE Global Research; Shi, Rongpei [The Ohio State Univ., Columbus, OH (United States); Zhou, Ning [General Electric Company, Niskayuna, NY (United States). GE Global Research

    2017-01-03

    The drive to increase combined cycle turbine efficiency from 62% to 65% for the next-generation advanced cycle requires a new heavy duty gas turbine wheel material capable of operating at 1200°F and above. Current wheel materials are limited by the stability of their major strengthening phase (gamma double prime), which coarsens at temperatures approaching 1200°F, resulting in a substantial reduction in strength. More advanced gamma prime superalloys, such as those used in jet engine turbine disks, are also not suitable due to size constraints; the gamma prime phase overages during the slow cooling rates inherent in processing thick-section turbine wheels. The current program addresses this need by screening two new alloy design concepts. The first concept exploits a gamma prime/gamma double prime coprecipitation reaction. Through manipulation of alloy chemistry, coprecipitation is controlled such that gamma double prime is used only to slow the growth of gamma prime during slow cooling, preventing over-aging, and allowing for subsequent heat treatment to maximize strength. In parallel, phase field modeling provides fundamental understanding of the coprecipitation reaction. The second concept uses oxide dispersion strengthening to improve on two existing alloys that exhibit excellent hold time fatigue crack growth resistance, but have insufficient strength to be considered for gas turbine wheels. Mechanical milling forces the dissolution of starting oxide powders into a metal matrix allowing for solid state precipitation of new, nanometer scale oxides that are effective at dispersion strengthening.

  14. Evaluation of advanced coal gasification combined-cycle systems under uncertainty

    International Nuclear Information System (INIS)

    Frey, H.C.; Rubin, E.S.

    1992-01-01

    Advanced integrated gasification combined cycle (IGCC) systems have not been commercially demonstrated, and uncertainties remain regarding their commercial-scale performance and cost. Therefore, a probabilistic evaluation method has been developed and applied to explicitly consider these uncertainties. The insights afforded by this method are illustrated for an IGCC design featuring a fixed-bed gasifier and a hot gas cleanup system. Detailed case studies are conducted to characterize uncertainties in key measures of process performance and cost, evaluate design trade-offs under uncertainty, identify research priorities, evaluate the potential benefits of additional research, compare results for different uncertainty assumptions, and compare the advanced IGCC system to a conventional system under uncertainty. The implications of probabilistic results for research planning and technology selection are discussed in this paper

  15. Graded Cycling Test Combined With the Talk Test Is Responsive in Cardiac Rehabilitation

    DEFF Research Database (Denmark)

    Nielsen, Susanne Grøn; Vinther, Anders

    2016-01-01

    PURPOSE: To evaluate clinical assessment outcome of cardiac rehabilitation, a simple and reliable submaximal exercise test, not based on heart rate, is warranted. The Talk Test (TT) has been found to correlate well with the ventilatory threshold, and excellent reliability was observed for TT...... combined with the Graded Cycling Test (GCT-TT) in cardiac patients. The purpose was to investigate responsiveness of GCT-TT in cardiac rehabilitation patients. METHODS: Patients (n = 93) referred to 8 weeks of cardiac rehabilitation were included. Pre- and posttests were performed using GCT-TT. Mean test...... changes in watts (W) were compared with the standard error of measurement (SEM95) for groups and the smallest real difference (SRD) for individuals. Minimal clinically important difference was assessed by comparing patient perceived changes in physical fitness with the test changes. RESULTS...

  16. Combined nutritional and environmental life cycle assessment of fruits and vegetables

    DEFF Research Database (Denmark)

    Stylianou, Katerina S.; Fantke, Peter; Jolliet, Olivier

    2016-01-01

    -LCA) framework that compares environmental and nutritional effects of foods in a common end -point metric, Disability Adjusted Life Years (DALY). In the assessment, environmental health impact categories include green house gases, particulate matter (PM), and pesticide residues on fruits and vegetables, while......; 35 μDALY/serving fruit benefit compared to a factor 10 lower impact. Replacing detrimental foods, such as trans-fat and red meat, with fruits or vegetables further enhances health benefit. This study illustrates the importance of considering nutritional effects in food-LCA.......Nutritional health effects from the ‘use stage’ of the life cycle of food products can be substantial, especially for fruits and vegetables. To assess potential one-serving increases in fruit and vegetable consumption in Europe, we employ the Combined Nutritional and Environmental LCA (CONE...

  17. Method and system to estimate variables in an integrated gasification combined cycle (IGCC) plant

    Science.gov (United States)

    Kumar, Aditya; Shi, Ruijie; Dokucu, Mustafa

    2013-09-17

    System and method to estimate variables in an integrated gasification combined cycle (IGCC) plant are provided. The system includes a sensor suite to measure respective plant input and output variables. An extended Kalman filter (EKF) receives sensed plant input variables and includes a dynamic model to generate a plurality of plant state estimates and a covariance matrix for the state estimates. A preemptive-constraining processor is configured to preemptively constrain the state estimates and covariance matrix to be free of constraint violations. A measurement-correction processor may be configured to correct constrained state estimates and a constrained covariance matrix based on processing of sensed plant output variables. The measurement-correction processor is coupled to update the dynamic model with corrected state estimates and a corrected covariance matrix. The updated dynamic model may be configured to estimate values for at least one plant variable not originally sensed by the sensor suite.

  18. Computational Fluid Dynamic Modeling of Rocket Based Combined Cycle Engine Flowfields

    Science.gov (United States)

    Daines, Russell L.; Merkle, Charles L.

    1994-01-01

    Computational Fluid Dynamic techniques are used to study the flowfield of a fixed geometry Rocket Based Combined Cycle engine operating in rocket ejector mode. Heat addition resulting from the combustion of injected fuel causes the subsonic engine flow to choke and go supersonic in the slightly divergent combustor-mixer section. Reacting flow computations are undertaken to predict the characteristics of solutions where the heat addition is determined by the flowfield. Here, adaptive gridding is used to improve resolution in the shear layers. Results show that the sonic speed is reached in the unheated portions of the flow first, while the heated portions become supersonic later. Comparison with results from another code show reasonable agreement. The coupled solutions show that the character of the combustion-based thermal choking phenomenon can be controlled reasonably well such that there is opportunity to optimize the length and expansion ratio of the combustor-mixer.

  19. Aero-Thermo-Structural Analysis of Inlet for Rocket Based Combined Cycle Engines

    Science.gov (United States)

    Shivakumar, K. N.; Challa, Preeti; Sree, Dave; Reddy, Dhanireddy R. (Technical Monitor)

    2000-01-01

    NASA has been developing advanced space transportation concepts and technologies to make access to space less costly. One such concept is the reusable vehicles with short turn-around times. The NASA Glenn Research Center's concept vehicle is the Trailblazer powered by a rocket-based combined cycle (RBCC) engine. Inlet is one of the most important components of the RBCC engine. This paper presents fluid flow, thermal, and structural analysis of the inlet for Mach 6 free stream velocity for fully supersonic and supercritical with backpressure conditions. The results concluded that the fully supersonic condition was the most severe case and the largest stresses occur in the ceramic matrix composite layer of the inlet cowl. The maximum tensile and the compressive stresses were at least 3.8 and 3.4, respectively, times less than the associated material strength.

  20. Family Life Cycle and Deforestation in Amazonia: Combining Remotely Sensed Information with Primary Data

    Science.gov (United States)

    Caldas, M.; Walker, R. T.; Shirota, R.; Perz, S.; Skole, D.

    2003-01-01

    This paper examines the relationships between the socio-demographic characteristics of small settlers in the Brazilian Amazon and the life cycle hypothesis in the process of deforestation. The analysis was conducted combining remote sensing and geographic data with primary data of 153 small settlers along the TransAmazon Highway. Regression analyses and spatial autocorrelation tests were conducted. The results from the empirical model indicate that socio-demographic characteristics of households as well as institutional and market factors, affect the land use decision. Although remotely sensed information is not very popular among Brazilian social scientists, these results confirm that they can be very useful for this kind of study. Furthermore, the research presented by this paper strongly indicates that family and socio-demographic data, as well as market data, may result in misspecification problems. The same applies to models that do not incorporate spatial analysis.

  1. Model predictive control system and method for integrated gasification combined cycle power generation

    Science.gov (United States)

    Kumar, Aditya; Shi, Ruijie; Kumar, Rajeeva; Dokucu, Mustafa

    2013-04-09

    Control system and method for controlling an integrated gasification combined cycle (IGCC) plant are provided. The system may include a controller coupled to a dynamic model of the plant to process a prediction of plant performance and determine a control strategy for the IGCC plant over a time horizon subject to plant constraints. The control strategy may include control functionality to meet a tracking objective and control functionality to meet an optimization objective. The control strategy may be configured to prioritize the tracking objective over the optimization objective based on a coordinate transformation, such as an orthogonal or quasi-orthogonal projection. A plurality of plant control knobs may be set in accordance with the control strategy to generate a sequence of coordinated multivariable control inputs to meet the tracking objective and the optimization objective subject to the prioritization resulting from the coordinate transformation.

  2. Effect of the combined stress on the life of components under thermal cycling conditions

    International Nuclear Information System (INIS)

    Zuchowski, R.; Zietkowski, L.

    1987-01-01

    The life of structural components subjected to temperature changes is affected, among other factors, by the nature of the stress field. If life prediction for axially stressed components can be accomplished with a number of well established techniques, the behaviour under a complex state of stress and varying temperature conditions still is the object of intensive research. The present study was aimed at assessing the influence of the stress field upon the life of specimens made of chromium-nickel H23N18 steel under thermal cycling conditions. The designation of steel is in accordance with Polish Standards. The experiments were made on thin-walled tubular specimens loaded with various combinations of a static axial force and a static torque. (orig./GL)

  3. Influence of different means of turbine blade cooling on the thermodynamic performance of combined cycle

    International Nuclear Information System (INIS)

    Sanjay; Singh, Onkar; Prasad, B.N.

    2008-01-01

    A comparative study of the influence of different means of turbine blade cooling on the thermodynamic performance of combined cycle power plant is presented. Seven schemes involving air and steam as coolants under open and closed loop cooling techniques have been studied. The open loop incorporates the internal convection, film and transpiration cooling techniques. Closed loop cooling includes only internal convection cooling. It has been found that closed loop steam cooling offers more specific work and consequently gives higher value of plant efficiency of about 60%, whereas open loop transpiration steam cooling, open loop steam internal convection cooling, transpiration air cooling, film steam cooling, film air, and internal convection air cooling have been found to yield lower values of plant efficiency in decreasing order as compared to closed loop steam cooling

  4. A Scramjet Compression System for Hypersonic Air Transportation Vehicle Combined Cycle Engines

    Directory of Open Access Journals (Sweden)

    Devendra Sen

    2018-06-01

    Full Text Available This paper proposes a compression system for a scramjet, to be used as part of a combined cycle engine on a hypersonic transport vehicle that can achieve sustained flight at 8 Mach 8. Initially research into scramjet compression system and shock wave interaction was conducted to establish the foundation of the scramjet inlet and isolator sections. A Computational Fluid Dynamics (CFD campaign was conducted, where the shock structure and flow characteristics was analysed between Mach 4.5–8. The compression system of a scramjet is of crucial importance in providing air at suitable Mach number, pressure and temperature to the combustion chamber. The use of turbojet engines in over-under configuration with the scramjet was investigated as well as the study of a combined cycle scramjet-ramjet configuration. It was identified that locating the scramjet in the centre with a rotated ramjet on either side, where its ramps make up the scramjet wall was the most optimal configuration, as it mitigated the effect of the oblique shocks propagating from the scramjet walls into the adjacent ramjet. Furthermore, this meant that the forebody of the vehicle could solely be used as the compression surface by the scramjet. In this paper, the sizing of the scramjet combustion chamber and nozzle were modified to match the flow properties of the oncoming flow with the purpose of producing the most optimum scramjet configuration for the cruise speed of Mach 8. CFD simulations showed that the scramjet inlet did not provide the levels of compression and stagnation pressure recovery initially required. However, it was found that the scramjet provided significantly more thrust than the drag of the aircraft at sustained Mach 8 flight, due to its utilisation of a very aerodynamic vehicle design.

  5. Valuing flexibility: The case of an Integrated Gasification Combined Cycle power plant

    International Nuclear Information System (INIS)

    Abadie, Luis M.; Chamorro, Jose M.

    2008-01-01

    In this paper we analyze the choice between two technologies for producing electricity. In particular, the firm has to decide whether and when to invest either in a Natural Gas Combined Cycle (NGCC) power plant or in an Integrated Gasification Combined Cycle (IGCC) power plant, which may burn either coal or natural gas. Instead of assuming that fuel prices follow standard geometric Brownian motions, here they are assumed to show mean reversion, specifically to follow an inhomogeneous geometric Brownian motion. First we consider the opportunity to invest in a NGCC power plant. We derive the optimal investment rule as a function of natural gas price and the remaining life of the right to invest. In addition, the analytical solution for a perpetual option to invest is obtained. Then we turn to the IGCC power plant. We analyse the valuation of an operating plant when there are switching costs between modes of operation, and the choice of the best operation mode. This serves as an input to evaluate the option to invest in this plant. Finally we derive the value of an opportunity to invest either in a NGCC or IGCC power plant, i.e. to choose between an inflexible and a flexible technology, respectively. Depending on the opportunity's time to maturity, we derive the pairs of coal and gas prices for which it is optimal to invest in NGCC, in IGCC, or simply not to invest. Numerical computations involve the use of one- and two-dimensional binomial lattices that support a mean-reverting process for coal and gas prices. Basic parameter values are taken from an actual IGCC power plant currently in operation. Sensitivity of some results with respect to the underlying stochastic process for fuel price is also checked

  6. Conventional and advanced exergetic analyses applied to a combined cycle power plant

    International Nuclear Information System (INIS)

    Petrakopoulou, Fontina; Tsatsaronis, George; Morosuk, Tatiana; Carassai, Anna

    2012-01-01

    Conventional exergy-based methods pinpoint components and processes with high irreversibilities. However, they lack certain insight. For a given advanced technological state, there is a minimum level of exergy destruction related to technological and/or economic constraints that is unavoidable. Furthermore, in any thermodynamic system, exergy destruction stems from both component interactions (exogenous) and component inefficiencies (endogenous). To overcome the limitations of the conventional analyses and to increase our knowledge about a plant, advanced exergy-based analyses have been developed. In this paper, a combined cycle power plant is analyzed using both conventional and advanced exergetic analyses. Except for the expander of the gas turbine system and the high-pressure steam turbine, most of the exergy destruction in the plant components is unavoidable. This unavoidable part is constrained by internal technological limitations, i.e. each component’s endogenous exergy destruction. High levels of endogenous exergy destruction show that component interactions do not contribute significantly to the thermodynamic inefficiencies. In addition, these inefficiencies are unavoidable to a large extent. With the advanced analysis, new improvement strategies are revealed that could not otherwise be found. -- Highlights: ► This is the first application of a complete advanced exergetic analysis to a complex power plant. ► In the three-pressure-level combined cycle power plant studied here, the improvement potential of the majority of the components is low, since most of the exergy destruction is unavoidable. ► Component interactions are generally of lower importance for the considered plant. ► Splitting the exogenous exergy destruction reveals one-to-one component interactions and improvement strategies. ► The advanced exergetic analysis is a necessary supplement to the conventional analysis in improving a complex system.

  7. Overall performance assessment of a combined cycle power plant: An exergo-economic analysis

    International Nuclear Information System (INIS)

    Sahin, Ahmet Z.; Al-Sharafi, Abdullah; Yilbas, Bekir S.; Khaliq, Abdul

    2016-01-01

    Highlights: • An exergo-economic analysis is carried out for a combined cycle power plant. • An overall performance index (OPI) is defined to analyze the power plant. • Four performance indicators and three scenarios are considered in the analysis. • The optimum configuration of the power plant differs for each scenarios considered. - Abstract: An exergo-economic analysis is carried out for a combined cycle power plant using the first law and the second law of thermodynamics, and the economic principles while incorporating GT PRO/PEACE Software Packages. An overall performance index (OPI) is defined to assess and analyze the optimum operational and design configurations of the power plant. Four performance indicators are considered for the analysis; namely, energy efficiency (ENE), exergy efficiency (EXE), levelized cost of electricity (COE), and the total investment (TI) cost. Three possible scenarios are considered in which different weight factor is assigned to the performance indicators when assessing the performance. These scenarios are: (i) the conventional case in which the levelized cost of electricity is given a high priority, (ii) environmental conscious case in which the exergy efficiency is given a high priority, and (iii) the economical case in which the total cost of investment is given a high priority. It is shown that the optimum size and the configuration of the power plant differ for each scenarios considered. The selection and optimization of the size and configuration of the power plant are found to be depending on the user priorities and the weight factors assigned to the performance indicators.

  8. The benefit of regional diversification of cogeneration investments in Europe: A mean-variance portfolio analysis

    Energy Technology Data Exchange (ETDEWEB)

    Westner, Guenther, E-mail: guenther.westner@eon-energie.co [E.ON Energy Projects GmbH, Arnulfstrasse 56, 80335 Munich (Germany); Madlener, Reinhard, E-mail: rmadlener@eonerc.rwth-aachen.d [Institute for Future Energy Consumer Needs and Behavior (FCN), Faculty of Business and Economics/E.ON Energy Research Center, RWTH Aachen University, Mathieustrasse 6, 52074 Aachen (Germany)

    2010-12-15

    The EU Directive 2004/8/EC, concerning the promotion of cogeneration, established principles on how EU member states can support combined heat and power generation (CHP). Up to now, the implementation of these principles into national law has not been uniform, and has led to the adoption of different promotion schemes for CHP across the EU member states. In this paper, we first give an overview of the promotion schemes for CHP in various European countries. In a next step, we take two standard CHP technologies, combined-cycle gas turbines (CCGT-CHP) and engine-CHP, and apply exemplarily four selected support mechanisms used in the four largest European energy markets: feed-in tariffs in Germany; energy efficiency certificates in Italy; benefits through tax reduction in the UK; and purchase obligations for power from CHP generation in France. For contracting companies, it could be of interest to diversify their investment in new CHP facilities regionally over several countries in order to reduce country and regulatory risk. By applying the Mean-Variance Portfolio (MVP) theory, we derive characteristic return-risk profiles of the selected CHP technologies in different countries. The results show that the returns on CHP investments differ significantly depending on the country, the support scheme, and the selected technology studied. While a regional diversification of investments in CCGT-CHP does not contribute to reducing portfolio risks, a diversification of investments in engine-CHP can decrease the risk exposure. - Research highlights: {yields}Preconditions for CHP investments differ significantly between the EU member states. {yields}Regional diversification of CHP investments can reduce the total portfolio risk. {yields}Risk reduction depends on the chosen CHP technology.

  9. Evaluation of a Cogeneration Plant with Integrated Fuel Factory; Integrerad braenslefabrik med kraftvaermeanlaeggning - en utvaerdering

    Energy Technology Data Exchange (ETDEWEB)

    Atterhem, Lars

    2002-12-01

    factory has been achieved when it comes to fuel pellets quality and increased power production. The power production increment is estimated to over 40 GWh yearly based on both performance tests and duration curve calculations. The a-value (ratio generated power to heat) for the integrated process is also higher compared to operation of the cogeneration plant only. Another advantage with the combined process is that the cogeneration turbine can be in operation for a longer period during the year compared to cogeneration plant single operation. There is still potential for further improvements and optimisations. The pellets production and also the condensing turbine generation, can for example be maximised during periods with high power prises. There is also a need for further research of optimal temperature levels of the drying process concerning risks of fouling and quality of the dried product. The extracted steam pressure versus temperature level in the dryer can also be optimised to further increase the power generation.

  10. Optimization of a gas turbine cogeneration plant

    International Nuclear Information System (INIS)

    Wallin, J.; Wessman, M.

    1991-11-01

    This work describes an analytical method of optimizing a cogeneration with a gas turbine as prime mover. The method is based on an analytical function. The function describes the total costs of the heat production, described by the heat load duration curve. The total costs consist of the prime costs and fixed costs of the gas turbine and the other heating plants. The parameters of interest at optimization are the heat efficiency produced by the gas turbine and the utilization time of the gas turbine. With todays prices for electricity, fuel and heating as well as maintenance- personnel and investment costs, extremely good conditions are needed to make the gas turbine profitable. Either a raise of the price for the electricity with about 33% is needed or that the ratio of electricity and fuel increases to approx 2.5. High investment subsidies for the gas turbines could make a gas turbine profitable, even with todays electricity- and fuel prices. Besides being a good help when projecting cogeneration plants with a gas turbine as prime mover, the method gives a possibility to optimize the annual operating time for a certain gas turbine when changing the operating conditions. 6 refs

  11. High temperature cogeneration with thermionic burners

    International Nuclear Information System (INIS)

    Fitzpatrick, G.O.; Britt, E.J.; Dick, R.S.

    1981-01-01

    The thermionic cogeneration combustor was conceived to meet industrial requirements for high-temperature direct heat, typically in the form of gas at temperatures from 800 to 1900 K, while at the same time supplying electricity. The thermionic combustor is entirely self-contained, with heat from the combustion region absorbed by the emitters of thermionic converters to be converted to electric power and the high-temperature reject heat from the converters used to preheat the air used for combustion. Depending on the temperature of the process gas produced, energy savings of around 10% with respect to that used to produce the same amount of electricity and heat without cogeneration are possible with present technology, and savings of up to 20% may be possible with advanced converters. Possible thermionic combustor designs currently under investigation include a configuration in which heat is collected by heat pipes lining the periphery of the combustion region, and a fire-tube converter in which combustion occurs within the cylindrical emitter of each converter. Preliminary component tests of these designs have been encouraging

  12. Cogeneration opportunities in the maritime provinces

    International Nuclear Information System (INIS)

    MacPherson, S.W.

    1999-01-01

    With the arrival of natural gas in New Brunswick in November 1999, the province will be faced with new power generation development opportunities in four different categories of power projects. These include industrial self generation (including cogeneration), merchant power plants, power projects to replace aging facilities, and power projects to help meet future environmental needs. New Brunswick's competitive advantage in harnessing the power generation development opportunities lies in the fact that it is close to major electricity markets in Quebec and New England. It also has many available generation sites. The province's many pulp and paper plants with large process steam needs are also ideal candidates for cogeneration. Some of the major competitive advantages of natural gas over coal are its lower operation and maintenance costs, it is thermally more efficient, produces lower emissions to the environment and prices are competitive. One of the suggestions in New Brunswick Power's new restructuring proposal is to unbundle electricity service in the province into generation and transmission and distribution services. Three gas-fired projects have already been proposed for the province. The 284 MW Bayside Power Project at the Courtenay Bay Generating Station is the most advanced

  13. High temperature cogeneration with thermionic burners

    Science.gov (United States)

    Fitzpatrick, G. O.; Britt, E. J.; Dick, R. S.

    The thermionic cogeneration combustor was conceived to meet industrial requirements for high-temperature direct heat, typically in the form of gas at temperatures from 800 to 1900 K, while at the same time supplying electricity. The thermionic combustor is entirely self-contained, with heat from the combustion region absorbed by the emitters of thermionic converters to be converted to electric power and the high-temperature reject heat from the converters used to preheat the air used for combustion. Depending on the temperature of the process gas produced, energy savings of around 10% with respect to that used to produce the same amount of electricity and heat without cogeneration are possible with present technology, and savings of up to 20% may be possible with advanced converters. Possible thermionic combustor designs currently under investigation include a configuration in which heat is collected by heat pipes lining the periphery of the combustion region, and a fire-tube converter in which combustion occurs within the cylindrical emitter of each converter. Preliminary component tests of these designs have been encouraging.

  14. Easiest paths for walking and cycling : Combining syntactic and geographic analyses in studying walking and cycling mobility

    NARCIS (Netherlands)

    Nourian Ghadikolaee, P.; Van der Hoeven, F.D.; Rezvani, S.; Sariyildiz, I.S.

    2015-01-01

    We discuss fundamentals of a new computational approach to configurative analysis and synthesis and present a number of advancements we have made in the direction of computational analysis of walking and cycling mobility. We have scrutinized the notion of distance and addressed it in correspondence

  15. Research report for fiscal 1998. Basic research for promoting joint implementation, etc. (conversion of old coal-fired thermoelectric power plants in Poland into combined cycle plants); 1998 nendo chosa hokokusho. Poland sekitan karyoku hatsudensho (kyushiki) combined cycle eno tenkan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    A project is discussed for modernization for energy efficiency enhancement and greenhouse gas reduction. The most effective way to reduce greenhouse gas in Poland is to totally replace the existing coal-fired power plants with natural gas combined cycle plants. Under this project, however, natural gas-fired power generation and integrated coal/brown coal gasification combined cycle power generation are both subjected to study. This is because the power plant modernization project is closely related to the fate of coal/brown coal industries which constitute the important industrial department of Poland. As for the earning rate of the project in case of natural gas-fired combined cycle power generation, the rate will be 13.2% even at the Kaweczyn station which is the highest in earning rate, and this fails to satisfy the project conditions. If integrated coal/brown gasification combined cycle power generation is chosen, the rate will be still lower. When the cost for greenhouse gas reduction is taken up, the Konin station exhibits the lowest of 9 dollars/tCO2, and the others 15-17 dollars/tCO2. When coal gas combined cycle is employed, the cost will be 3-4 times higher. (NEDO)

  16. The cogeneration potential of the sugar industry in Vietnam

    International Nuclear Information System (INIS)

    Bhattacharyya, S.C.; Thang, D.N.Q.

    2004-01-01

    Vietnam produces about 15 million tons of sugarcane per year and about five mt of bagasse. There is the potential for cogeneration using bagasse, which can also help overcome power shortages in the country. This paper analyses the potential for cogeneration from the sugar industry in Vietnam under three different scenarios and finds that between 100 and 300 megawatts of power-generating capacity could be supported by the bagasse generated from sugar mills, depending on the technology considered for sugar mills and cogeneration and the possibility of renovation of the existing mills. The paper also assesses the expense of cogeneration and finds it to be a cost-effective option for all types of sugar mill. It is found that the cost savings from cogeneration would more than offset the cost of introducing cogeneration in sugar mills with inefficient cane processing technologies. Sugar mills with modern technologies would have a significant amount of excess power and most of these plants would break-even if they sold excess power at around 4.5 cents per kilowatt hour. The break-even cost and the average production cost are sensitive to the investment cost assumptions. The paper thus suggests that cogeneration from the sugar industry is an attractive option for investors in existing mills or new sugar mills alike. (Author)

  17. Current experience with central-station nuclear cogeneration plants

    International Nuclear Information System (INIS)

    1981-10-01

    In considering the potential of the HTGR for nuclear cogeneration, a logical element for investigation is the recent history of nuclear cogeneration experience. Little is found in recent literature; however, the twin nuclear cogeneration plant at Midland is nearing completion and this milestone will no doubt be the basis for a number of reports on the unique cogeneration facility and operating experiences with it. Less well known in the US is the Bruce Nuclear Power Development in Ontario, Canada. Originally designed to cogenerate steam for heavy water production, the Bruce facility is the focus of a major initiative to create an energy park on the shores of Lake Huron. To obtain an improved understanding of the status and implications of current nuclear cogeneration experience, GCRA representatives visited the Ontario Hydro offices in Toronto and subsequently toured the Midland site near Midland, Michigan. The primary purpose of this report is to summarize the results of those visits and to develop a series of conclusions regarding the implications for HTGR cogeneration concepts

  18. Field operation test of Wakamatsu PFBC combined cycle power plant; Wakamatsu PFBC jissho shiken no genkyo

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, T [Center for Coal Utilization, Japan, Tokyo (Japan); Takanishi, K [Electric Power Development Co. Ltd., Tokyo (Japan)

    1996-09-01

    At the Wakamatsu Coal Utilization Research Center, the verification test was conducted of atmospheric pressure fluidized bed boilers and ultra-high temperature turbines. The Wakamatsu PFBC (pressurized fluidized bed combustion) is a combined cycle power generation system combining steam turbine power generation in which the turbine is driven by steam generated from the fluidized bed boiler installed inside the pressure vessel and gas turbine power generation in which high temperature/pressure exhaust gas is used from the boiler, having a total output of 71 MW. The operation started in fiscal 1995, stopped due to damage of the tube of CTF (ceramic tube filter), and is now continuing after the repair. As a result of the test conducted in fiscal 1995, it was confirmed in the two-stage cyclone test that the diameter of ash particle and cyclone efficiency change by kind of coal and amount of limestone and that by coal kind gas turbine blades show different states of abrasion, indicating greater abrasion when there is much SiO2 in ash. As a result of the continued high load operation of CTF, ash blockade inside the tube occurred and tube damage was generated by thermal shock, etc. 5 figs., 4 tabs.

  19. Cogeneration trends in Europe history -- State of the art - Outlook

    International Nuclear Information System (INIS)

    Hunschofsky, H.

    1998-01-01

    Cogeneration, the utilization of heat created while producing electricity from fossil fuels, is by no means a new technology. In 1926, 71 years ago, a brochure from MAN in Germany showed a heat recovery system for diesel engines. Despite the fact that cogeneration has existed for a long time, it took half a century and the first so called ''oil crisis'' in the 1970's for societies to become aware of limited energy resources. Environmental groups gave cogeneration an additional boost in the 1980's. Additionally, governments in the Western European Nations attracted cogeneration investors by not only providing subsidies and tax breaks but also regulating electricity prices. Although there has been much growth in the cogeneration market in the past years, the industry has still not reached its peak in Europe. A variety of studies have shown that there is still significant growth potential in the future: WWF (World Wildlife Fund) published a study in 1996 suggesting a target of 330 Twh of generation will be produced through cogeneration by the year 2005, a tripling of current generation. Due to the EU's belief that cogeneration is an optimal form of generation, it has developed a cogeneration strategy. As part of this strategy, the EC is promoting cogeneration so that it accounts for 20% of all European generation by the year 2010. These factors would give a variety of companies such as equipment suppliers, investment companies, utilities, consultants and energy brokers a wide range of opportunities in Europe. Detailed information and some hints will be given as to how to participate in this fast growing industry. Ways to overcome obstacles in those markets will be shown as well as the pros and cons of different entry strategies

  20. Community Design Parameters and the Performance of Residential Cogeneration Systems

    Directory of Open Access Journals (Sweden)

    Hazem Rashed-Ali

    2012-11-01

    Full Text Available The integration of cogeneration systems in residential and mixed-use communities has the potential of reducing their energy demand and harmful emissions and can thus play asignificant role in increasing their environmental sustainability. This study investigated the impact of selected planning and architectural design parameters on the environmental and economic performances of centralized cogeneration systems integrated into residential communities in U.S.cold climates. Parameters investigated include: 1 density, 2 use mix, 3 street configuration, 4 housing typology, 5 envelope and building systems’ efficiencies, and 6 passive solar energyutilization. The study integrated several simulation tools into a procedure to assess the impact of each design parameter on the cogeneration system performance. This assessment procedure included: developing a base-line model representing typical design characteristics of U.S. residential communities; assessing the cogeneration system’s performance within this model using three performance indicators: percentage of reduction in primary energy use, percentage of reduction in CO2 emissions; and internal rate of return; assessing the impact of each parameter on the system performance through developing 46 design variations of the base-line model representing potential changes in each parameter and calculating the three indicators for each variation; and finally, using a multi-attribute decision analysis methodology to evaluate the relative impact of each parameter on the cogeneration system performance. The study results show that planning parameters had a higher impact on the cogeneration system performance than architectural ones. Also, a significant correlation was found between design characteristics identified as favorable for the cogeneration system performance and those of sustainable residential communities. These include high densities, high use mix, interconnected street networks, and mixing of

  1. An optimization method for gas refrigeration cycle based on the combination of both thermodynamics and entransy theory

    International Nuclear Information System (INIS)

    Chen, Qun; Xu, Yun-Chao; Hao, Jun-Hong

    2014-01-01

    Highlights: • An optimization method for practical thermodynamic cycle is developed. • The entransy-based heat transfer analysis and thermodynamic analysis are combined. • Theoretical relation between system requirements and design parameters is derived. • The optimization problem can be converted into conditional extremum problem. • The proposed method provides several useful optimization criteria. - Abstract: A thermodynamic cycle usually consists of heat transfer processes in heat exchangers and heat-work conversion processes in compressors, expanders and/or turbines. This paper presents a new optimization method for effective improvement of thermodynamic cycle performance with the combination of entransy theory and thermodynamics. The heat transfer processes in a gas refrigeration cycle are analyzed by entransy theory and the heat-work conversion processes are analyzed by thermodynamics. The combination of these two analysis yields a mathematical relation directly connecting system requirements, e.g. cooling capacity rate and power consumption rate, with design parameters, e.g. heat transfer area of each heat exchanger and heat capacity rate of each working fluid, without introducing any intermediate variable. Based on this relation together with the conditional extremum method, we theoretically derive an optimization equation group. Simultaneously solving this equation group offers the optimal structural and operating parameters for every single gas refrigeration cycle and furthermore provides several useful optimization criteria for all the cycles. Finally, a practical gas refrigeration cycle is taken as an example to show the application and validity of the newly proposed optimization method

  2. Tri generation with combined cycle, HVAC and desalinisation; Trigeneracion con ciclo combinado, climatizacion y desalacion

    Energy Technology Data Exchange (ETDEWEB)

    Cuviella Suarez, C.

    2008-07-01

    The current need of mankind to seek for new ways of efficient usable controllable energy production from the economic and environmental points of view is obvious. The current trend towards renewable energies, states this fact though it is not the definitive solution. This is why a fundamental step in saving energy is to prevent any misuse or unnecessary energy consumption. Co-generation, with all its variants, is an answer to this problem through the use of the residual thermal energy within electrical production as an usable product instead of as waste to be dissipated in a thermodynamic cooling process in an approximate ratio of 2:1. The basis of the approach is to optimize the management of thermal energy produced during electricity generation to prevent other fuel firing consumptions which can be assumed as heating, air conditioning, desalinisation, industrial processes, etc. The profusion of tinstallations of this kind would imply a gross saving of 60% of the general primary fuel(Author)

  3. Analysis of carbon dioxide emission of gas fuelled cogeneration plant

    International Nuclear Information System (INIS)

    Nordin, Adzuieen; Amin, M; Majid, A

    2013-01-01

    Gas turbines are widely used for power generation. In cogeneration system, the gas turbine generates electricity and the exhaust heat from the gas turbine is used to generate steam or chilled water. Besides enhancing the efficiency of the system, the process assists in reducing the emission of CO 2 to the environment. This study analyzes the amount of CO 2 emission by Universiti Teknologi Petronas gas fuelled cogeneration system using energy balance equations. The results indicate that the cogeneration system reduces the CO 2 emission to the environment by 60%. This finding could encourage the power plant owners to install heat recovery systems to their respective plants

  4. Analysis of carbon dioxide emission of gas fuelled cogeneration plant

    Science.gov (United States)

    Nordin, Adzuieen; Amin, M.; Majid, A.

    2013-12-01

    Gas turbines are widely used for power generation. In cogeneration system, the gas turbine generates electricity and the exhaust heat from the gas turbine is used to generate steam or chilled water. Besides enhancing the efficiency of the system, the process assists in reducing the emission of CO2 to the environment. This study analyzes the amount of CO2 emission by Universiti Teknologi Petronas gas fuelled cogeneration system using energy balance equations. The results indicate that the cogeneration system reduces the CO2 emission to the environment by 60%. This finding could encourage the power plant owners to install heat recovery systems to their respective plants.

  5. Regional characteristics relevant to advanced technology cogeneration development. [industrial energy

    Science.gov (United States)

    Manvi, R.

    1981-01-01

    To assist DOE in establishing research and development funding priorities in the area of advanced energy conversion technoloy, researchers at the Jet Propulsion Laboratory studied those specific factors within various regions of the country that may influence cogeneration with advanced energy conversion systems. Regional characteristics of advanced technology cogeneration possibilities are discussed, with primary emphasis given to coal derived fuels. Factors considered for the study were regional industry concentratio