WorldWideScience

Sample records for heat supply systems

  1. Heat pipes as perspective base elements of heat recovery in heat supply and ventilating systems

    Directory of Open Access Journals (Sweden)

    Matveev Andrey

    2017-01-01

    Full Text Available Thermotechnical characteristics of heat pipes are considered as high-efficient heat-transfer devices, which can provide energy-saving technologies for heat supply and ventilating systems and for different branches of industry. Thermotechnical and working (”performance capability” characteristics of heat pipes are investigated. By ”performance capability” of heat pipes and heat-transfer devices on heat pipes we mean the system state, where it can perform set functions and keep parameter values (thermal power, conductivity, thermal resistance, heat-transfer coefficient, temperature level and differential, etc. within the regulations of standardized specifications. The article presents theoretical and experimental methods of «gaslock» length determination on noncondensable gases during long-lasting tests of ammonia heat pipes made of aluminum shape АS – КRА 7.5 – R1 (alloy АD – 31. The paper gives results of research of thermotechnical characteristics of heat pipes in horizontal and vertical states (separate and as a set part while using different systems of thermal insulation. The obtained results of thermotechnical and resource tests show the advantages of ammonia heat pipes as basic elements for heat exchanger design in heating and ventilation systems.

  2. Loop heat pipes - highly efficient heat-transfer devices for systems of sun heat supply

    Energy Technology Data Exchange (ETDEWEB)

    Maydanik, Yu. [Ural Branch of the Russian Academy of Sciences, Ekaterinburg (Russian Federation). Inst. of Thermophysics

    2004-07-01

    Loop heat pipes (LHPs) are hermetic heat-transfer devices operating on a closed evaporation-condensation cycle with the use of capillary pressure for pumping the working fluid [1]. In accordance with this, they possess all the main advantages of conventional heat pipes, but, as distinct from the latter, have a considerably higher heat-transfer capacity, especially when operating in the ''antigravity'' regime, when heat is transferred from above downwards. Besides, LHPs possess a higher functional versatility, are adaptable to different operating conditions and provide great scope for various design embodiments. This is achieved at the expense of both the original design of the device and the properties of the wick - a special capillary structure used for the creation of capillary pressure. The LHP schematic diagram is given in Fig. 1. The device contains an evaporator and a condenser - heat exchanger connected by means of smooth-walled pipe-lines with a relatively small diameter intended for separate motion of vapor and liquid. At present loop heat pipes are most extensively employed in thermoregulation systems of spacecrafts. Miniature LHPs are used for cooling electronics and computers. At the same time there exists a considerable potential of using these devices for the recovery of low-grade (waste) heat from different sources, and also in systems of sun heat supply. In the latter case LHPs may serve as an efficient heat-transfer link between a sun collector and a heat accumulator, which has a low thermal resistance and does not consume any additional energy for pumping the working fluid between them. (orig.)

  3. Assessment of two-level heat pump installations’ power efficiency for heat supply systems

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    Аlla Е. Denysova

    2015-06-01

    Full Text Available The problem of energy saving becomes one of the most important in power engineering. It is caused by exhaustion of world reserves in hydrocarbon fuel, such as gas, oil and coal representing sources of traditional heat supply. Conventional sources has essential shortcomings: low power, ecological and economic efficiencies, that can be eliminated by using alternative methods of power supply, like the considered one: low-temperature natural heat of ground waters of on the basis of heat pump installations application. The heat supply system considered provides an effective use of two-level heat pump installation operating as heat source the Odessa city ground waters during the lowest ambient temperature period. Proposed is a calculation method of heat pump installations on the basis of geothermal heat supply. Calculated are the values of electric energy consumption N by the compressors’ drive, and the heat supply system transformation coefficient µ for a source of geothermal heat from ground waters of Odessa city allowing to estimate efficiency of two-level heat pump installations.

  4. COMPARATIVE EFFICIENCY OF HEAT-PUMPS APPLICATION IN LOW TEMPERATURE HEAT SUPPLY SYSTEMS

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    M. N. Chepurnoy

    2015-01-01

    Full Text Available The  article  considers  comparative  operation-efficiency  of  the  low-temperature  heatsupply systems with heat pumping plants (HPP and with hot-water boilers. The paper shows that for energy evaluation of the alternative heat-supply systems effectiveness one cannot employ the transformation ratio (heating coefficient and the fuel heat-utilization factor in the HPP. Nonetheless the transformation ratio enters the formulae designating the efficiency of HPP operation. The authors obtain a generalized formula for ascertainment of transformation ratio and suggest evaluating the operation efficiency of the heat-supply systems by means of indicators specifying relative gain in the exergy-efficiency factor, fuel savings and saving expenditures connected with fuel and utilities. They attain formulae and build nomographic charts for those indicators ascertainment. The operation-efficiency comparative analysis of the low-temperature heat supply systems with HPP and with hot-water boilers shows that the HPP systems increase their effectiveness with transformation ratio, fuel price increase as well as with low electric-energy prices. The article specifies that with fuel low prices, the transformation-ratios limiting values with which the HPP operation-efficacy gains, grow. Energy-efficiency increase in the HPP does not always guaranty their economic effectiveness. These findings are true only for the heating systems. The hot water-supply systems will require the HPP condenser water additional heating to the assumed temperature from another thermal source, which reduces the effectiveness of the heat pump plants utilizing.

  5. TO THE SUBJECT OF DEVELOPMENT OF POWER SUPPLY PROCESS FOR INDUSTRIAL HEAT TECHNOLOGIES AND HEAT SUPPLY SYSTEMS IN BELARUS

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    B. M. Khrоustalev

    2014-01-01

    Full Text Available Considers the current key energy problem – the rational and efficient use of energy resources, and the possibility of its solution, based on the concept of intensive energy conservation. As a result, the way of primary energy consumption reduction in Belarus is provided. The initial situation in the frame of program of further improvement of energy consumption until 2030 is estimated. It is shown, that for Belarus the first place in energy saving measures takes the efficiency improvement of natural gas consumption, what allows reducing the investment and saving energy resources.The possibility of usage of waste energy flows of medium-and low-temperature from industrial and municipal enterprises are discussed. To realize the described possibilities, some changes of heat supply system of enterprises and plants are required. Changes in heat supply system of the industrial enterprises, related with usage of low-temperature waste energy flows in a thermal energy generation process for heating, require the installation of additional equipment in existing heat energy supply system, such as absorption heat pumps, which are easily joint and successfully work at boiler Houses as well as at CHP. The numerous examples of fuel consumption reduction via heat industrial waste and sewage usage are shown in this article. It must be emphasized, that such an expansion of energy-saving framework not only reduce the primary energy consumption by heat generating sources, but also significantly improves the conditions of the Belarusian electrical grid operation under the conditions of nuclear power plant commissioning. The existing technical framework, that ensured the proposed changes, is also taking into account.

  6. Mathematical model for calculation of the heat-hydraulic modes of heating points of heat-supplying systems

    Science.gov (United States)

    Shalaginova, Z. I.

    2016-03-01

    The mathematical model and calculation method of the thermal-hydraulic modes of heat points, based on the theory of hydraulic circuits, being developed at the Melentiev Energy Systems Institute are presented. The redundant circuit of the heat point was developed, in which all possible connecting circuits (CC) of the heat engineering equipment and the places of possible installation of control valve were inserted. It allows simulating the operating modes both at central heat points (CHP) and individual heat points (IHP). The configuration of the desired circuit is carried out automatically by removing the unnecessary links. The following circuits connecting the heating systems (HS) are considered: the dependent circuit (direct and through mixing elevator) and independent one (through the heater). The following connecting circuits of the load of hot water supply (HWS) were considered: open CC (direct water pumping from pipelines of heat networks) and a closed CC with connecting the HWS heaters on single-level (serial and parallel) and two-level (sequential and combined) circuits. The following connecting circuits of the ventilation systems (VS) were also considered: dependent circuit and independent one through a common heat exchanger with HS load. In the heat points, water temperature regulators for the hot water supply and ventilation and flow regulators for the heating system, as well as to the inlet as a whole, are possible. According to the accepted decomposition, the model of the heat point is an integral part of the overall heat-hydraulic model of the heat-supplying system having intermediate control stages (CHP and IHP), which allows to consider the operating modes of the heat networks of different levels connected with each other through CHP as well as connected through IHP of consumers with various connecting circuits of local systems of heat consumption: heating, ventilation and hot water supply. The model is implemented in the Angara data

  7. USING REGIONAL RENEWABLE ENERGY RESOURSES FOR HEATING SUPPLY SYSTEMS

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    O. M. Pshinko

    2017-02-01

    Full Text Available Purpose. The study analyzed the possibility and conditions for the effective operation of heating systems during the transition of the heat-generating capacity to biofuels energy. The straw of cereal crops, which are prevailing in Dnipro region, is used for this. The main purpose is scientific calculation of opportunities and cost of specific measures for such a transition. As an example it was taken the boiler-room of campus at Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan (DNURT that consumes natural gas. Methodology. The work analyses the legislative base of Ukraine, which promotes the using of renewable energy sources as fuel, as well as the incentive mechanisms for the development of this trend. The paper identifies opportunities of Prydniprovsk region to ensure straw supply for the boiler-room. Cost parameters of cargo transportation on the territory of Ukraine in 2016, which depend on the distance and the size of the trucks, are analysed. These indicators, as well as indicators related to its purchase, are considered together with energy potential of using the straw as fuel. Findings. With existing in Ukraine (as of 2016 the grain yielding capacity in the agriculture and cost indicators in the field of transportations, the transition of capacity share to biofuel is sufficiently profitable. The thermal power unit cost can be reduced fourfold. Originality. For the first time it is proposed to use the new integrated approaches to assess the cost of thermal power unit boiler with its transition to the use of renewable energy sources. The authors also proposed a new logistics delivery of these sources to the place of their application. From a technical and cost points of view it was determined the optimal order of capacity transfer for new renewable sources of energy in a given region depending on the structure of areas under crops and their productivity. Originality. The introduction of the

  8. Improvement of the organizational-economic mechanism of developing heat supply city system

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    Doroshenko, Valentina

    2012-05-01

    Full Text Available The article examines a complex of social and economic problems that accompany the development of heat supply systems in Ukraine. It is determined that the negative effects of district heating in the cities and towns are caused by the failure of current management mechanism to ensure the solution of basic problems and implement the heat supply system as life support system. The main goal of study was the development of theoretical, methodological and methodical principles of organizational-economic mechanism of development of heat supply system based on the analysis of problems and reserves of its formation and implementation. Application of the systematic approach methodology has allowed to conclude that the effectiveness of heat supply is determined by the interaction of a complex of interrelated and interdependent components that form the theoretical, methodological and methodical basis of its ensuring - concepts, strategies, programs, the mechanism of formation and development of heat supply system. The result of the study was developing of the conceptual foundations of improvement of organizational-economic mechanism of heat supply system development, based on the principles of civilized paradigm, methodology to improve its main basic elements - the mechanisms of information, organizational, infrastructural, legal, financial support, tariff setting, energy saving motivation, optimal development of heat supply system so as to satisfy individual requirements of consumers with high effectiveness as a combination of social, economic, energy, environmental effects.

  9. Analysis of trends in the development of cities' heat supply systems

    Science.gov (United States)

    Stennikov, V. A.; Mednikova, E. E.

    2016-09-01

    New challenges—including the modern urban development policy, formation of the market of energy efficient technologies and different types of equipment of a broad power capacity range, tightening requirements to reliability, quality, and economic accessibility of heat supply—enhance the competitiveness of decentralized heat supply. In addition, its spontaneous growth and not always reasonable implementation lead to unjustified expenses, low efficiency, and ecological inconsistency. This proves the relevance of solving the problems of dividing an urban territory into zones of centralized heating (CH) and decentralized heating (DCH) along with their planning and justification, as well as determining a reasonable level of heat supply centralization and concentration of heat sources' power capacity. Solving these problems using the suggested method will allow optimizing the application areas for various types of heat supply and heat sources, justifying the degree of heat power capacity concentration and the extent of the systems as early as at the phase of a detailed urban planning project and then refining them during the design of urban heat supply systems. This will dramatically improve the reasonability of the decisions made and will simplify the procedure of their implementation. For criteria of limiting the extent (radius) of heat supply systems and defining their type, we suggest using standard values—the density of heat load per unit length of the pipeline and per unit area of urban territory. Standard values must be differentiated across the territory of Russia taking into account regional climatic and economic conditions and unique characteristics of heat supply development in cities and towns. The present article continues and develops the statements made in the previous articles created within the framework of the Theory of Hydraulic Circuits and takes into account the current situation and emerging trends in heat supply.

  10. Investigation of a heat storage for a solar heating system for combined space heating and domestic hot water supply for homeowner´s association "Bakken"

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1998-01-01

    A heat storage for a solar heating system for combined space heating and domestic hot water supply was tested in a laboratory test facility.The heat storage consist of a mantle tank with water for the heating system and of a hot water tank, which by means of thermosyphoning is heated by the water...... in the heating system. The heat storage was tested in a heat storage test facility. The most important characteristics of the heat storage were determined by means of the tests and recommendations for the design of the heat storage were given....

  11. EFFECTIVENESS ANALYSIS OF CAMPUS HEAT SUPPLY SYSTEM OF DNIPROPETROVSK NATIONAL UNIVERSITY OF RAILWAY TRANSPORT

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    O. M. Pshinko

    2014-03-01

    Full Text Available Purpose. Heat consumption for heating and hot water supply of housing and industrial facilities is an essential part of heat energy consumption. Prerequisite for development of energy saving measures in existing heating systems is their preliminary examination. The investigation results of campus heating system of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan are presented in the article. On the basis of the analysis it is proposed to take the energy saving measures and assess their effectiveness. Methodology. Analysis of the consumption structure of thermal energy for heating domestic and hot water supply was fulfilled. The real costs of heat supply during the calendar year and the normative costs were compared. Findings. The recording expenditures data of thermal energy for heating supply of residential buildings and dormitories in 2012 were analyzed. The comparison of actual performance with specific regulations was performed. This comparison revealed problems, whose solution will help the efficient use of thermal energy. Originality. For the first time the impact of climate conditions, features of schemes and designs of heating systems on the effective use of thermal energy were analyzed. It was studied the contribution of each component. Practical value. Based on the analysis of thermal energy consumption it was developed a list of possible energy saving measures that can be implemented in the system of heat and power facilities. It was evaluated the fuel and energy resources saving.

  12. Possibility of Heat Pump Use in Hot Water Supply Systems

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    Tatyana Babak

    2016-09-01

    The results of this work may be used for in Total Site methodology development allowing heat recovery for district heating needs of both new designs and as retrofits to existing sites to ensure fast, widespread and cost-efficient industrial deployment. It leads to carbon footprint reduction and energy efficiency improvement of regions with heating and cooling demands during winter and summer seasons.

  13. Use of multilevel modeling for determining optimal parameters of heat supply systems

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    Stennikov, V. A.; Barakhtenko, E. A.; Sokolov, D. V.

    2017-07-01

    The problem of finding optimal parameters of a heat-supply system (HSS) is in ensuring the required throughput capacity of a heat network by determining pipeline diameters and characteristics and location of pumping stations. Effective methods for solving this problem, i.e., the method of stepwise optimization based on the concept of dynamic programming and the method of multicircuit optimization, were proposed in the context of the hydraulic circuit theory developed at Melentiev Energy Systems Institute (Siberian Branch, Russian Academy of Sciences). These methods enable us to determine optimal parameters of various types of piping systems due to flexible adaptability of the calculation procedure to intricate nonlinear mathematical models describing features of used equipment items and methods of their construction and operation. The new and most significant results achieved in developing methodological support and software for finding optimal parameters of complex heat supply systems are presented: a new procedure for solving the problem based on multilevel decomposition of a heat network model that makes it possible to proceed from the initial problem to a set of interrelated, less cumbersome subproblems with reduced dimensionality; a new algorithm implementing the method of multicircuit optimization and focused on the calculation of a hierarchical model of a heat supply system; the SOSNA software system for determining optimum parameters of intricate heat-supply systems and implementing the developed methodological foundation. The proposed procedure and algorithm enable us to solve engineering problems of finding the optimal parameters of multicircuit heat supply systems having large (real) dimensionality, and are applied in solving urgent problems related to the optimal development and reconstruction of these systems. The developed methodological foundation and software can be used for designing heat supply systems in the Central and the Admiralty regions in

  14. Realiability Of Heat Supply Subsystem

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    Babiarz Bożena

    2015-11-01

    Full Text Available The article presents the reliability analysis of subsystem of heat supply in the example of 47 thousand inhabitants’ city. The analysis was made on the basis of operational data made available by the Municipal Heating Company, between the years 2001 ÷ 2012. To describe the quantitative reliability of heat supply subsystem reliability indicators are used. Main times between failure and unitary failure rates including the month of their occurrence, type and diameter of the heating network, thermal power region were working out. Knowing the characteristics of the time to repair for the heating network, the reliability of heat supply subsystem for different thermal power region, considering the district heating system configuration can be determined.

  15. Investigation of a low flow solar heating system for space heating and domestic hot water supply for Aidt Miljø A/S

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1997-01-01

    A low flow solar heating system for space heating and domestic hot water supply from Aidt Miljø A/Swas tested in a laboratory test facility.......A low flow solar heating system for space heating and domestic hot water supply from Aidt Miljø A/Swas tested in a laboratory test facility....

  16. Investigation of a solar heating system for space heating and domestic hot water supply for Sol&Træ A.m.b.a

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    A solar heating system for space heating and domestic hot water supply from "Sol&Træ A.m.b.a." was tested in a laboratory test facility.......A solar heating system for space heating and domestic hot water supply from "Sol&Træ A.m.b.a." was tested in a laboratory test facility....

  17. Experimental performance evaluation of heat pump-based steam supply system

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    Kaida, T.; Sakuraba, I.; Hashimoto, K.; Hasegawa, H.

    2015-08-01

    Heat pumps have become increasingly important as a technology to reduce primary energy consumption and greenhouse effect gas emission. They are presently used mainly on residential air-conditioning and domestic hot water and are expected to spread to industrial heating processes. In 2011, Kobe Steel, Ltd. developed and commercialized two heat pump- based steam supply systems; the high efficiency steam supply system with a steam temperature of 120°C (SGH120) and the system which enables a steam temperature of 165°C (sGh165). For promoting the spread of these industrial heat pumps and enhancing the reliability of them, we investigate experimentally steam generation rate, energy efficiency and controlled performance of the SGH165 under various operating conditions on the assumption of actual different industrial processes, and evaluate technical possibilities for better performance.

  18. Hybrid renewable energy system application for electricity and heat supply of a residential building

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    Nakomčić-Smaragdakis Branka B.

    2016-01-01

    Full Text Available Renewable and distributed energy systems could provide a solution to the burning issue of reliable and clean supply of energy, having in mind current state and future predictions for population growth and fossil fuel scarcity. Hybrid renewable energy systems are novelty in Serbia and warrant further detailed research. The aim of this paper is to analyze the application of renewable energy sources(RES for electricity and heat supply of a typical household in Serbia, as well as the cost-effectiveness of the proposed system. The influence of feed-in tariff change on the value of the investment is analyzed. Small, grid-connected hybrid system (for energy supply of a standard household, consisting of geothermal heat pump for heating/cooling, solar photovoltaic panels and small wind turbine for power supply is analyzed as a case study. System analysis was conducted with the help of RETScreen software. Results of techno-economics analysis have shown that investing in geothermal heat pump and photovoltaic panels is cost-effective, while that is not the case with small wind turbine.

  19. Thermal Efficiency of Power Module “Boiler with Solar Collectors as Additional Heat Source” For Combined Heat Supply System

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    Denysova A.E.

    2015-04-01

    Full Text Available The purpose of work is to increase the efficiency of the combined heat supply system with solar collectors as additional thermal generators. In order to optimize the parameters of combined heat supply system the mathematical modeling of thermal processes in multi module solar collectors as additional thermal generators for preheating of the water for boiler have been done. The method of calculation of multi-module solar collectors working with forced circulation for various configurations of hydraulic connection of solar collector modules as the new result of our work have been proposed. The results of numerical simulation of thermal efficiency of solar heat source for boiler of combined heat supply system with the account of design features of the circuit; regime parameters of thermal generators that allow establishing rational conditions of its functioning have been worked out. The conditions of functioning that provide required temperature of heat carrier incoming to boiler and value of flow rate at which the slippage of heat carrier is not possible for different hydraulic circuits of solar modules have been established.

  20. AUTONOMOUS HEAT SUPPLY SYSTEM OF CONSUMERS WITH CONSIDERABLE DIFFERENT THERMAL INERTIA

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    Berzan V.P.

    2012-04-01

    Full Text Available There are examined problems occurring at the adoption of the decentralized heat energy supply system of the group of objects, which contains buildings with thermal inertia differed in thousands of times one from the other. It is studied the influence of water volume of hot-water boiler on greenhouse dynamics. It is conducted the comparison between the use ob biomass and natural gas boilers for such as objects.

  1. Designing a sustainable energy system for future slagelse city heat supply using energy planner web application

    OpenAIRE

    BoorBOOr, Marjan

    2013-01-01

    Currently, many activities and efforts are taking placed in different municipalities in Denmark in order to contribute to the national target,to phase out fossil fuel in the heat supply by 2030 and in the entire energy system in Denmark by 2050. However energy transition is a complex process and involved many section and include many inter relations. Any form of changes in one part can effects others which is one the biggest challege in energy transition and including these effects require...

  2. Efficient heat supply and use from an energy-system and climate perspective

    Energy Technology Data Exchange (ETDEWEB)

    Danestig, Maria

    2009-03-15

    The aim of this thesis is to illustrate whether the heat demand in district heating systems can be seen as a resource that enables efficient energy utilization, how this can be achieved and to discuss consequences of this assumption. Based on the answers to posed research questions and on the studies included in this thesis, it is concluded that the hypothesis 'A common system approach for energy supply and heat demand will show climate and economic efficient solutions' is true. In cold-climate countries, energy for heating of buildings is essential and heating options that interplay with the power system through electricity use or generation have potential for efficiency improvements. In Sweden, district heating is used extensively, especially in large buildings but to a growing extent also for small houses. Some industrial heat loads and absorption cooling can complement space heating demand so that the production resources may be more evenly utilised during the seasons of the year. Rising electricity prices in recent years cause problems for the extensive use of electric heating in Sweden and further switching to district heating should be a possible option. To be economically favourable, district-heating systems require a certain heat load density. New low-energy houses and energy-efficiency measures in existing buildings decrease the heat demand in buildings and, thus, in district heating systems. Optimisation models have been used in several studies of large, complex energy systems. Such models allow scenarios with changing policy instruments and changed consumer behaviour to be analysed. Energy efficiency measures as well as good conditions for efficient electricity generation, which can replace old, inefficient plants, are needed to reduce carbon dioxide emissions from the energy sector. Results when having a European energy perspective to studies of changes in Sweden differ from when having for example a Swedish energy system perspective The

  3. Investigation af a solar heating system for space heating and domestic hot water supply with a high degree of coverage

    DEFF Research Database (Denmark)

    Vejen, Niels Kristian

    1999-01-01

    A solar storage tank for space heating and domestic hot water supply was designed and testet in af laboratory test facility.......A solar storage tank for space heating and domestic hot water supply was designed and testet in af laboratory test facility....

  4. Heating and Domestic Hot Water Systems in Buildings Supplied by Low-Temperature District Heating

    DEFF Research Database (Denmark)

    Brand, Marek

    , because less heat is sold to customers and there is higher heat loss in the network. Similarly, higher connection power than needed means bigger pipe diameters are needed, resulting in higher heat losses as well. Using realistic values is therefore very important for feasibility calculations of DH.  ...

  5. Feasibility Assessment of Using Power Plant Waste Heat in Large Scale Horticulture Facility Energy Supply Systems

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    Min Gyung Yu

    2016-02-01

    Full Text Available Recently, the Korean government has been carrying out projects to construct several large scale horticulture facilities. However, it is difficult for an energy supply to operate stably and economically with only a conventional fossil fuel boiler system. For this reason, several unused energy sources have become attractive and it was found that power plant waste heat has the greatest potential for application in this scenario. In this study, we performed a feasibility assessment of power plant waste heat as an energy source for horticulture facilities. As a result, it was confirmed that there was a sufficient amount of energy potential for the use of waste heat to supply energy to the assumed area. In Dangjin, an horticultural area of 500 ha could be constructed by utilizing 20% of the energy reserves. In Hadong, a horticulture facility can be set up to be 260 ha with 7.4% of the energy reserves. In Youngdong, an assumed area of 65 ha could be built utilizing about 19% of the energy reserves. Furthermore, the payback period was calculated in order to evaluate the economic feasibility compared with a conventional system. The initial investment costs can be recovered by the approximately 83% reduction in the annual operating costs.

  6. High voltage power supplies for ITER RF heating and current drive systems

    Energy Technology Data Exchange (ETDEWEB)

    Gassmann, T., E-mail: thibault.gassmann@iter.org [ITER Organization, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Arambhadiya, B.; Beaumont, B. [ITER Organization, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Baruah, U.K. [Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar 382428 (India); Bonicelli, T. [Fusion For Energy, C/3 Josep Pla 2, Torres Diagonal Litoral-B3, E-08019 Barcelona (Spain); Darbos, C.; Purohit, D.; Decamps, H. [ITER Organization, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Albajar, F. [Fusion For Energy, C/3 Josep Pla 2, Torres Diagonal Litoral-B3, E-08019 Barcelona (Spain); Gandini, F.; Henderson, M.; Kazarian, F.; Lamalle, P.U.; Omori, T. [ITER Organization, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Parmar, D.; Patel, A. [Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar 382428 (India); Rathi, D. [ITER Organization, CS 90 046, 13067 St. Paul Lez Durance Cedex (France); Singh, N.P. [Institute for Plasma Research, Near Indira Bridge, Bhat, Gandhinagar 382428 (India)

    2011-10-15

    The RF heating and current drive (H and CD) systems to be installed for the ITER fusion machine are the electron cyclotron (EC), ion cyclotron (IC) and, although not in the first phase of the project, lower hybrid (LH). These systems require high voltage, high current power supplies (HVPS) in CW operation. These HVPS should deliver around 50 MW electrical power to each of the RF H and CD systems with stringent requirements in terms of accuracy, voltage ripple, response time, turn off time and fault energy. The PSM (Pulse Step Modulation) technology has demonstrated over the past 20 years its ability to fulfill these requirements in many industrial facilities and other fusion reactors and has therefore been chosen as reference design for the IC and EC HVPS systems. This paper describes the technical specifications, including interfaces, the resulting constraints on the design, the conceptual design proposed for ITER EC and IC HVPS systems and the current status.

  7. Gas Engine-Driven Heat Pump Chiller for Air-Conditioning and Hot Water Supply Systems

    Science.gov (United States)

    Fujita, Toshihiko; Mita, Nobuhiro; Moriyama, Tadashi; Hoshino, Norimasa; Kimura, Yoshihisa

    In Part 1 of this study, the performance characteristics of a 457kW gas engine-driven heat pump (GHP) chiller have been obtained from a simulation model analysis for both cooling and heating modes and it has been found that the part-load characteristics of the GHP chiller are fairly well. On the back of Part 1, a computer simulation program has been developed for the evaluation of GHP chiller systems to compare with the other types of heat source systems for air-conditioning and hot water supply applications. The simulation program can be used to estimate annual energy consumption, annual CO2 emission, etc. of the systems with the data of monthly and hourly thermal loads on various buildings, outdoor air conditions, and characteristics of various components comprising the systems. By applying this to some cases of medium-scale hotel, office, shop, and hospital buildings, it has been found that the GHP chiller systems have advantages particularly in the cases of hotels and hospitals where a lot of hot water demand exists. It has also been found that the combination of a GHP chiller and a direct-fired absorption water chiller boiler (hot and chilled water generator) appears promising.

  8. Feasibility and Supply Analysis of U.S. Geothermal District Heating and Cooling System

    Science.gov (United States)

    He, Xiaoning

    Geothermal energy is a globally distributed sustainable energy with the advantages of a stable base load energy production with a high capacity factor and zero SOx, CO, and particulates emissions. It can provide a potential solution to the depletion of fossil fuels and air pollution problems. The geothermal district heating and cooling system is one of the most common applications of geothermal energy, and consists of geothermal wells to provide hot water from a fractured geothermal reservoir, a surface energy distribution system for hot water transmission, and heating/cooling facilities to provide water and space heating as well as air conditioning for residential and commercial buildings. To gain wider recognition for the geothermal district heating and cooling (GDHC) system, the potential to develop such a system was evaluated in the western United States, and in the state of West Virginia. The geothermal resources were categorized into identified hydrothermal resources, undiscovered hydrothermal resources, near hydrothermal enhanced geothermal system (EGS), and deep EGS. Reservoir characteristics of the first three categories were estimated individually, and their thermal potential calculated. A cost model for such a system was developed for technical performance and economic analysis at each geothermally active location. A supply curve for the system was then developed, establishing the quantity and the cost of potential geothermal energy which can be used for the GDHC system. A West Virginia University (WVU) case study was performed to compare the competiveness of a geothermal energy system to the current steam based system. An Aspen Plus model was created to simulate the year-round campus heating and cooling scenario. Five cases of varying water flow rates and temperatures were simulated to find the lowest levelized cost of heat (LCOH) for the WVU case study. The model was then used to derive a levelized cost of heat as a function of the population density

  9. HEAT SUPPLY SYSTEM IMPROVEMENT OF CAMPUS AT UMAN NATIONAL UNIVERSITY OF HORTICULTURE

    Directory of Open Access Journals (Sweden)

    A. F. Golovchuk

    2016-06-01

    Full Text Available Purpose. In modern conditions of energy consumption growth and a rapid increase in energy prices the actual problem is the development and implementation of energy efficiency programs and resource-saving conversion in to a source to provide the needs of industry and municipal power. The paper aims to solve the urgent problem of energy saving and efficient use of fuel-energy ones and heat supply system optimization on the basis of Uman National University of Horticulture (UNUH. Methodology. The work investigated the process of heating and hot water supply in the course of 2007-2015 years. Implementation of current problems of energy saving is grounded on the scientific-practical and efficient assurance of fuel and energy usage. At the same time energy-saving technologies are viewed as a priority direction of the energy sector development, reduction of man-induced impact on the environment and as a way of improving the competitiveness of the national economy. Findings. Statistical data acquisition and analyzing of gas flow and outside air temperature for nine years was carried out. On the basis of this analysis, the problem was identified and specific targets for its solutions were set. Originality. Scientific novelty lies in solving the problem of energy saving and efficient use of fuel resources in Ukraine through the use of a systematic approach, the methodology development of efficient use of different fuels and optimization of local heating operation, applying contemporary automation and control systems. Firstly it was in detail analyzed and conducted the comprehensive assessment of various factors influence on energy conservation. It takes into account the human factor, professionalism and responsibility of the operators of boilers and their superiors, as well as the relevant control services. Practical value. For UNUH campus hybrid use of solid fuel and gas boilers was carried out. Decentralization of the university heating system has been

  10. Use of a turboexpander in steam power units for heat energy recovery in heat supply systems

    Science.gov (United States)

    Sadykov, R. A.; Daminov, A. Z.; Solomin, I. N.; Futin, V. A.

    2016-05-01

    A method for raising the efficiency of a boiler plant by installing a unit operating by the organic Rankine cycle is presented. Such units allow one to generate electricity to cover the auxiliaries of a heat source at a heat-transfer fluid temperature of no more than 130°C. The results of commissioning tests of boilers revealed that their efficiency is maximized under a load that is close or corresponds to the nominal one. If this load is maintained constantly, excess heat energy is produced. This excess may be used to generate electric energy in a steam power unit with a turboexpander. A way to insert this unit into the flow diagram of a boiler plant is proposed. The results of analysis of turbine types (turboexpanders included) with various capacities are presented, and the optimum type for the proposed flow diagram is chosen. The methodology for the design of turboexpanders and compressors used in the oil and gas industry and their operational data were applied in the analysis of a turboexpander. The results of the thermogasdynamic analysis of a turboexpander and the engineered shape of an axial-radial impeller are presented. Halocarbon R245fa is chosen as the working medium based on its calorimetric properties.

  11. Energy-effective method for low-temperature deaeration of make-up water on the heating supply system of heat power plants

    Science.gov (United States)

    Sharapov, V. I.; Pazushkina, O. V.; Kudryavtseva, E. V.

    2016-01-01

    The technology for low-temperature deaeration of make-up water of heating supply systems is developed that makes it possible to substantially enhance the energy efficiency of heat power plants (HPPs). As a desorbing agent for deaeration of make-up water of heating supply systems, it is proposed to use not steam or superheated water but a gas supplied to boiler burners. Natural gas supplied to steam boilers of HPPs has very low or often negative temperature after reducing devices. At the same time, it is virtually corrosive gas-free (oxygen and carbon dioxide) and, therefore, can be successfully used as the desorbing agent for water deaeration. These factors make it possible to perform deaeration of make-up water of heating supply systems at relatively low temperatures (10-30°C). Mixing of the cold deaerated make-up water with the return delivery water results in a significant decrease in the temperature the return delivery water before a lower delivery heater of a dual-purpose turbine plant, increase in the power output with the heat consumption, and, consequently, enhancement in the operation efficiency of the HPP. The article presents the calculation of the consumption of gas theoretically required for deaeration and reveals the evaluation of the energy efficiency of the technology for a typical energy unit of thermal power station. The mass transfer efficiency of the deaeration of the make-up water of heating supply systems is estimated for the case of using natural gas as the desorbing agent for which the specific gas consumption required theoretically for deaeration is calculated. It is shown that the consumption of natural gas used as fuel in boilers of HPPs is sufficient for the deaeration of any volumes of the make-up water of heating supply systems. The energy efficiency of the developed technology is evaluated for a typical heat power-generating unit of the HPP with a T-100-12.8 turbine. The calculation showed that the application of the new technology

  12. Thermal Modelling of Water-Based Floor Heating Systems - supply temperature optimisation and self-regulating effects

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Henrik

    2010-03-15

    Low temperature water-based concrete embedded floor heating systems are studied. The utilisation of low quality heat sources is facilitated by low temperature heating. Theoretical models which describe the transient thermal floor heating operation constitute the basis for the analysis. The combination of building, floor heating element, heat gains and control system is described by a set of theoretical models. In particular, a numerical floor heating element model is developed and verified by comparison with results from heat transfer software and published experimental results. A model based predictive control method is applied in order to find an optimised supply fluid temperature. The aim is to keep the upcoming operative temperature within a comfort interval and at the same time constrain the supply heat flux within practical limits. A discrete transient response factor method is utilised by a numerical optimisation algorithm that iteratively finds an optimised solution. The response factor method describes the relation between a piecewise constant supply heat flux and the succeeding shift in indoor temperature. The stability of the system has been studied; the initial delay time caused by the time needed for a heat front to conduct from the depth of the embedded circuit towards the interior sets a limit for the applied period time in the discrete response method. The predictive optimisation method has been applied in a realistic case where the operative temperature is successfully kept within the comfort interval. The self-regulation ability due to a thermal perturbance in the case of feed-forward controlled supply temperature is studied separately. Such system counteracts any non-periodic thermal perturbance by shifting the supplied heat flux in the opposite direction. The outcome is a more even indoor temperature and enhanced utilisation of heat gains. Transient response functions which quantify the involved thermal processes are derived by the developed

  13. Increasing RES Penetration and Security of Energy Supply by Use of Energy Storages and Heat Pumps in Croatian Energy System

    DEFF Research Database (Denmark)

    Krajačić, Goran; Mathiesen, Brian Vad; Duić, Neven;

    2010-01-01

    In this paper integration of wind power generation into the Croatian electricity supply is analysed using available technologies. The starting point is a model of the energy system in Croatia in 2007. Comprehensive hour-by-hour energy system analyses are conducted of a complete system meeting...... electricity, heat and transport demands, and including renewable energy, power plants, and combined heat and power production (CHP) for district heating. Using the 2007 energy system the wind power share is increased by two energy storage options: Pumped hydro and heat pumps in combination with heat storages...... with specific regulation of power system could additionally increase wind penetration for 0.37 TWh. Hence, with the current technologies installed in the Croatian energy system the installed pumped hydro-plant may facilitate more than 10% wind power in the electricity system. Large-scale integration of wind...

  14. Coupling Effect between Equilibrium Field and Heating Field and Modification of the Power Supply System on SUNIST Spherical Tokamak

    Institute of Scientific and Technical Information of China (English)

    何也熙; 李晓燕; 高喆

    2005-01-01

    Strong inductive coupling between the heating field and equilibrium field is confirmed to be responsible for the poor plasma equilibrium in initial discharges on the SUNIST spherical tokamak. A modification project for the power supply system of equilibrium field coils is successfully performed to increase the duration time of plasma current flattop from much less than 1ms to about 2 ms.

  15. High resolution heat atlases for demand and supply mapping

    Directory of Open Access Journals (Sweden)

    Bernd Möller

    2014-02-01

    Full Text Available Significant reductions of heat demand, low-carbon and renewable energy sources, and district heating are key elements in 100% renewable energy systems. Appraisal of district heating along with energy efficient buildings and individual heat supply requires a geographical representation of heat demand, energy efficiency and energy supply. The present paper describes a Heat Atlas built around a spatial database using geographical information systems (GIS. The present atlas allows for per-building calculations of potentials and costs of energy savings, connectivity to existing district heat, and current heat supply and demand. For the entire building mass a conclusive link is established between the built environment and its heat supply. The expansion of district heating; the interconnection of distributed district heating systems; or the question whether to invest in ultra-efficient buildings with individual supply, or in collective heating using renewable energy for heating the current building stock, can be based on improved data.

  16. Influence of Cooling to Heating Load Ratio on Optimal Supply Water and Air Temperatures in an Air Conditioning System

    Science.gov (United States)

    Karino, Naoki; Shiba, Takashi; Yokoyama, Ryohei; Ito, Koichi

    In planning an air conditioning system, supply water and air temperatures are important factors from the viewpoint of energy saving and cost reduction. For example, lower temperature supply water and air for space cooling reduce the coefficient of performance of a refrigeration machine, and increase the thickness of heat insulation material. However, they enable larger temperature differences, and reduce equipment sizes and power demand. It is also an important subject to evaluate the effect of the supply water and air temperatures on energy saving and cost reduction on the annual basis by considering not only cooling but also heating loads. The purposes of this paper are to propose an optimal planning method for an air conditioning system with large temperature difference, and to analyze the effect of supply water and air temperatures on the long-term economics through a numerical study for an office building. As a result, it is shown that the proposed method effectively determines supply water and air temperatures, and the influence of the cooling to heating load ratio on the long-term economics is clarified.

  17. ON REASONABLE ESTIMATE OF ENERGY PERFORMANCE OF THE RESIDENTIAL BUILDINGS SUSTENANCE WITH CENTRALIZED HEAT-SUPPLY SYSTEM

    Directory of Open Access Journals (Sweden)

    S. N. Osipov

    2016-01-01

    Full Text Available As consisted with Directive No 3 of President of the Republic of Belarus of June, 14th 2007 ‘Economy and Husbandry – the Major Factors of Economic Security of the Republic of Belarus’, saving fuel-and-energy resources over the republic in 2010–2015 should amount to 7,1–8,9 MIO tons of fuel equivalent including 1,00–1,25 MIO tons of fuel equivalent at the expense of heat-supply optimization and 0,25–0,40 MIO tons of fuel equivalent at the expense of increasing enclosing structures heat resistance of the buildings, facilities and housing stock. It means, where it is expected to obtain around 18 % of general thermal resources economy in the process of heat-supply optimization, then by means of enhancing the cladding structure heat resistance of the buildings and constructions of various applications – only about 3–5 % and even a bit less so of the housing stock. Till 1994, in residential sector of the Republic of Belarus, the annual heat consumption of the heating and ventilation averaged more than 130 kW×h/(m2×year (~56 %, of the hot-water supply – around 100 kW×h/(m2×year (~44 %. In residential houses, built from 1994 to 2009, heat consumption of the heating and ventilation is already 90 kW×h/(m2×year, of the hot-water supply – around 70 kW×h/(m2×year. In buildings of modern mainstream construction, they expend 60 kW×h/(m2×year (~46 % on heating and ventilation and 70 kW×h/(m2×year (~54 % on hot-water supply. In some modern residential buildings with the exhausted warm air secondary energy resource utilization, the heating and ventilation takes around 30–40 kW×h/(m2×year of heat. Raising energy performance of the residential buildings by means of reducing heat expenses on the heating and ventilation is the last segment in the system of energy resources saving. The first segments in the energy performance process are producing heat and transporting it over the main lines and outside distribution networks. In

  18. Study of an electrical heating system with ductless air supply and shape-stabilized PCM for thermal storage

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Kunping; Zhang, Yinping; Di, Hongfa [Department of Building Science, Tsinghua University, Beijing 100084 (China); Yang, Rui [Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)

    2007-07-15

    A kind of electrical floor heating system with a shape-stabilized phase change material (PCM) which has been studied at Tsinghua University in our previous studies, can provide space heating during the whole day and can be controlled conventionally. However, this is not suitable for office buildings where no space heating is needed at night. The effective control is very important for the heating system in such buildings. In this paper, we studied a kind of new electrical floor heating system with ductless air supply and shape-stabilized PCM for thermal storage in order to overcome the shortcomings of the passive under-floor electric heating system with thermal storage. In this paper, we investigated its thermal performance by experiments and simulation, calculated the effects of various factors and discussed the application feasibility in different climate regions. The results show that the total electrical energy consumption was shifted from the peak period to the off-peak period, which would provide significant economic benefits because of the different day and night electricity tariffs. The system can be designed by choosing PCM with proper melting temperature and be controlled by varying velocity of air supply in different conditions. (author)

  19. Study on improving efficiency in hydrogen utilizing regional heat supply system; Suiso riyo chinetsu kyokyu system no koritsu kaizen ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Sueyoshi, S.; Ishitani, H.; Matsuhashi, T. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-01-30

    With an objective to improve efficiency in a hydrogen energy distribution system, discussions were given on combining heat energy supply from hydrogen with factory waste heat recovery by using hydrogen absorbing alloys. This system carries out simultaneously heat supply as a result of burning hydrogen directly and heat supply obtained by converting hydrogen pressure by using hydrogen absorbing alloys. This system could allow existing gas piping facilities to be utilized. However, since quantity of hydrogen that can be transported as pressure is smaller than quantity of heat of hydrogen itself, absorption and emission are repeated a number of times in order to utilize the heat source to a possible maximum extent. Thus, a large quantity of waste heat can be utilized when this method is used. A hydrogen manufacturing system by means of LNG reformation may be combined with this heat transportation system. When waste heat that is received is handled as having zero input in the same sense as natural energy, and heat supply from a hydrogen absorbing alloy is repeated for 50 times, the overall energy balance has resulted in a considerably good value at 0.95. 5 refs., 9 figs., 5 tabs.

  20. The Polyvalent Heat Supply System for Experimental Building of the Passive Type (area of 300 m2 Based on Renewable and Alternative Energy Sources

    Directory of Open Access Journals (Sweden)

    Basok, B.I.

    2014-11-01

    Full Text Available Results of the development and implementation of heat supply system for experimental building of the passive type are presented, optimal operating conditions are investigated, guidelines for the creation of heat supply systems for passive type buildings are provided.

  1. Modelling and multi-scenario analysis for electric heat tracing system combined with low temperature district heating for domestic hot water supply

    DEFF Research Database (Denmark)

    Yang, Xiaochen; Li, Hongwei; Svendsen, Svend

    2016-01-01

    . In this study, electric heat tracing system was investigated as a solution to this dilemma. A model of electric heat tracing system for multi-storey buildings was built. Various pipe materials and insulation thicknesses as the parameters of the model were compared to make a comprehensive study. The performance......Low temperature district heating (LTDH) is a cost-efficient way of supplying space heating and domestic hot water (DHW) for buildings in urban areas. However, there is concern that the potential hygiene problems (Legionella) might occur if LTDH is implemented, especially for large buildings...... of the electric heating tracing system with LTDH was simulated by taking the user pattern into account. A smart control method based on thermostatic and real-time control was developed, and compared with normal control method. The impact of user pattern was tested by applying standard, stochastic, and real load...

  2. Thermal gain of CHP steam generator plants and heat supply systems

    Science.gov (United States)

    Ziganshina, S. K.; Kudinov, A. A.

    2016-08-01

    Heating calculation of the surface condensate heat recovery unit (HRU) installed behind the BKZ-420-140 NGM boiler resulting in determination of HRU heat output according to fire gas value parameters at the heat recovery unit inlet and its outlet, heated water quantity, combustion efficiency per boiler as a result of installation of HRU, and steam condensate discharge from combustion products at its cooling below condensing point and HRU heat exchange area has been performed. Inspection results of Samara CHP BKZ-420-140 NGM power boilers and field tests of the surface condensate heat recovery unit (HRU) made on the bimetal calorifier base KCk-4-11 (KSk-4-11) installed behind station no. 2 Ulyanovsk CHP-3 DE-10-14 GM boiler were the basis of calculation. Integration of the surface condensation heat recovery unit behind a steam boiler rendered it possible to increase combustion efficiency and simultaneously decrease nitrogen oxide content in exit gases. Influence of the blowing air moisture content, the excess-air coefficient in exit gases, and exit gases temperature at the HRU outlet on steam condensate amount discharge from combustion products at its cooling below condensing point has been analyzed. The steam condensate from HRU gases is offered as heat system make-up water after degasification. The cost-effectiveness analysis of HRU installation behind the Samara CHP BKZ-420-140 NGM steam boiler with consideration of heat energy and chemically purified water economy has been performed. Calculation data for boilers with different heat output has been generalized.

  3. Development and Evaluation of Control System for Microgrid Supplying Heat and Electricity

    Science.gov (United States)

    Kojima, Yasuhiro; Koshio, Masanobu; Nakamura, Shizuka

    Photovoltaic (PV) and Wind Turbine (WT) generation systems are expected to offer solutions to reduce green house gases and become more widely used in the future. However, the chief technical drawback of using these kinds of weather-dependent generators is the difficulty of forecasting their output, which can have negative impacts on commercial grids if a large number of them are introduced. Thus, this problem may hinder the wider application of PV and WT generation systems. The Regional Power Grid with Renewable Energy Resources Project was launched to seek a solution to this problem. The scope of the project is to develop, operate, and evaluate a Dispersed Renewable Energy Supply System with the ability to adapt the total energy output in response to changes in weather and demand. Such a system would reduce the impact that PV and WT generation systems have on commercial grids and allow the interconnection of more Dispersed Energy Resources (DER). In other words, the main objective of this project is to demonstrate an integrated energy management system, or a type of microgrid [1], as a new way of introducing DERs. The system has been in operation since October 2005 and will continue operation until March 2008. Through the project period, the data on power quality, system efficiency, operation cost, and environmental burden will be gathered and a cost-benefit analysis of the system will be undertaken. In this paper, firstly we introduce the concept of microgrid for reducing negative impact of natural energy, and secondly illustrate the structure of electric and thermal supply control system for Microgrid, especially for the Hachinohe demonstration project. The control system consists of four stages; weekly operation planning, economic dispatching control, tie-line control and local frequency control. And finally demonstration results and evaluation results are shown.

  4. High resolution heat atlases for demand and supply mapping

    DEFF Research Database (Denmark)

    Möller, Bernd; Nielsen, Steffen

    2014-01-01

    Significant reductions of heat demand, low-carbon and renewable energy sources, and district heating are key elements in 100% renewable energy systems. Appraisal of district heating along with energy efficient buildings and individual heat supply requires a geographical representation of heat dem...

  5. On the way towards smart energy supply in cities: The impact of interconnecting geographically distributed district heating grids on the energy system

    DEFF Research Database (Denmark)

    Dominkovic, D. F.; Bačeković, I.; Sveinbjörnsson, D.

    2017-01-01

    assessed. Moreover, the impact of industrial waste heat on the DH supply was also assessed. In the reference year (2013) two out of four interconnections proved to be economically viable. The results for the future energy system (2029) showed that interconnecting geographically distributed DH grids reduces...... primary energy supply by 9.5%, CO2 emissions by 11.1% and total system costs by 6.3%. Inclusion of industrial waste heat in the fully interconnected DH grid reduced primary energy supply for an additional 3%, CO2 emissions for an additional 2.2% and total system costs for an additional 1.3%. The case...... of the future energy supply system with interconnected DH grids and installed industrial waste heat recuperation results in the lowest primary energy demand, emissions and costs. Finally, the benefits of the interconnected DH grid, in terms of system flexibility, CO2 emissions, total costs and energy efficiency...

  6. ON THE ISSUE OF RATIONAL ORGANIZATION OF THE TEXTILE AND KNITWEAR ENTERPRISES HEAT AND POWER SUPPLY SYSTEM

    Directory of Open Access Journals (Sweden)

    V. N. Romaniuk

    2016-01-01

    Full Text Available The paper considers organization of the industrial enterprise heat and power supply system (HPSS, to be rational from the structure and flow parameter standpoint. Developing HPSS is one of the main lines of implementing energy-saving potential in volumes complying with dictates of the time on reducing the production cost energy component, which is especially vital for the light industry enterprises of Belarus. To reduce the complexity of the task the authors employ the hierarchical structure of HPSS. With regard to textile and knitwear enterprises, they show the irregularity of energy supply on the one hand, and of energy use on the other. The finishing departments of the specified enterprises ensure their thermo-technological status. It is proverbial that accomplished in terms of energy thermo-technological enterprises should not consume the electric energy produced in condensation electric power plants. Instead, for their production needs, they should use thermal energy and electricity generated in the CHP. At the same time, steam turbine CHPs of low power, and consequently of low initial parameters, cannot provide the required electrical and heat energy flow generation balance. The indicated circumstance among others accounts for prevalence of condensation electric power plants in the scheme of electrogenerating capacities that provide work for the light industry enterprises. And this leads to irregularity of their energy supply. Transition to gas CHPs with required scheme of the energy flow generation is associated primarily with creation of inherent generating sources, which in its turn poses a number of challenges on modification of the thermal treatment schemes of technological flows. The problem is solved in package with developing energy consumption of the finishing department as well as the entire enterprise. The study shows the capability of utilizing low pressure hot water alongside with steam, which paves the way to the recuperative

  7. Integrated assessment of supply and efficiency resources for the district heating system, City of Handlova, Republic of Slovakia

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-06-01

    This city needs to replace its old district heating system which is unreliable and expensive to maintain. Current plant is owned by a state-run utility; the plant is scheduled for privatization, and the city is examining options for its upgrade. Analysis and preparation for this activity is documented in demand-side and supply-side technical and economic analyses and in this integrated demand/supply report. Preliminary projections indicate the cost of heating from a cost per unit of energy basis and from the perspective of an apartment dweller in Handlova on a total cost per year basis. The centralized coal cogeneration option is the least expensive on a levelized energy cost both with and without energy efficiency. Centralized coal/gas dual-fuel cogeneration is a close second, and the decentralized gas natural gas boilers is significantly more expensive. When the effect of building efficiency measures is evaluated, efficiency always increases the cost on a levelized energy cost basis, but on a levelized cost per flat basis, both centralized systems with buildings efficiency are less expensive than without.

  8. SOLID FUEL OF HYDROCARBON, WOOD AND AGRICULTURAL WASTE FOR LOCAL HEAT SUPPLY SYSTEMS

    Directory of Open Access Journals (Sweden)

    B. M. Khroustalev

    2017-01-01

    Full Text Available In Belarus oil refining and oil producing industries are paid close attention. On the background of the active maintaining the level of oil processing and volume of oil extraction in our country and in the countries of the Eurasian Economic Union there is a steady formation of hydrocarbon-containing waste; therefore recycling of the latter is an urgent task to improve the competitiveness of production. The most cost-effective way of using hydrocarbon waste is the conversion of it into power resources. In this case it is possible to obtain significant power-saving and economic effect of the combined use of a hydrocarbon, wood, agricultural and other combustible waste, meanwhile improving the ecological situation at the sites of waste storage and creating a solid fuel with the necessary energy and specified physical-and-chemical properties. A comprehensive solution of a recycling problem makes it possible to use as energy resources a lot of waste that has not found application in other technologies, to produce alternative multi-component fuel which structure meets environmental and energy requirement for local heating systems. In addition, the implementation of such technology will make it possible to reduce power consumption of enterprises of various kinds that consume fuel and will also increase the share of local fuels in the energy balance of a particular region.

  9. Loop heat pipe for thermal conditions supplying systems for elements of radio electronic equipment

    Directory of Open Access Journals (Sweden)

    Khayrnasov S. М.

    2010-06-01

    Full Text Available The loop heat pipe design presented in the article provides the transmission of thermal flow up to 105 W when working in temperature range of 20—90°C and on any space orientation.

  10. Planning of the district heating system in copenhagen from an economic perspective comparing energy-savings versus fossil-free supply

    DEFF Research Database (Denmark)

    Harrestrup, Maria; Svendsen, Svend

    The Danish government has adopted a long-term energy policy of being independent of fossil fuels by 2050, and that the energy supply for buildings should be independent of fossil fuels by 2035. Therefore, urgent action is needed to meet the requirements for the future energy system. One way...... geothermal heating plants, may lead to oversized heating plants that are too expensive to build compared to implementing energy savings. Therefore reducing heat demand of existing buildings before investing in supply capacity will save society half the investment, indicating the importance of carrying out...

  11. Some potential material supply constraints in solar systems for heating and cooling of buildings and process heat. (A preliminary screening to identify critical materials)

    Energy Technology Data Exchange (ETDEWEB)

    Watts, R.L.; Gurwell, W.E.; Nelson, T.A.; Smith, S.A.

    1979-06-01

    Nine Solar Heating and Cooling of Buildings (SHACOB) designs and three Agricultural and Industrial Process Heat (AIPH) designs have been studied to identify potential future material constraints to their large scale installation and use. The nine SHACOB and three AIPH systems were screened and found to be free of serious future material constraints. The screening was carried out for each individual system design assuming 500 million m/sup 2/ of collector area installed by the year 2000. Also, two mixed design scenarios, containing equal portions of each system design, were screened. To keep these scenarios in perspective, note that a billion m/sup 2/ containing a mixture of the nine SHACOB designs will yield an annual solar contribution of about 1.3 Quads or will displace about 4.2 Quads of fossil fuel used to generate electricity. For AIPH a billion square meters of the mixed designs will yield about 2.8 Quads/year. Three materials were identified that could possibly restrain the deployment of solar systems in the specific scenarios investigated. They are iron and steel, soda lime glass and polyvinyl fluoride. All three of these materials are bulk materials. No raw material supply constraints were found.

  12. Method for reducing excess heat supply experienced in typical Chinese district heating systems by achieving hydraulic balance and improving indoor air temperature control at the building level

    DEFF Research Database (Denmark)

    Zhang, Lipeng; Gudmundsson, Oddgeir; Thorsen, Jan Eric;

    2016-01-01

    that once the hydraulic balance is achieved and indoor temperatures are controlled with this integrated approach, 17% heat savings and 42.8% pump electricity savings can be achieved. The energy savings will also have a positive environmental effect with seasonal reductions of 11 kg CO2, 0.1 kg SO2, and 0...... with the actual heat demand. This results in 15-30% of the total supplied heat being lost. This paper proposes an integrated approach that aims to reduce the excess heat loss by introducing pre-set thermostatic radiator valves combined with automatic balancing valves. Those devices establish hydraulic balance...

  13. Simulating the thermal operating conditions in the thermal wells of ground-source heat-pump heat supply systems. Part I: Porous moisture freezing processes in soil

    Science.gov (United States)

    Vasilyev, G. P.; Peskov, N. V.; Lichman, V. A.; Gornov, V. F.; Kolesova, M. V.

    2015-08-01

    The mathematical models laid down in the new blocks of the INSOLAR.GSHP.12 software system simulating unsteady operating conditions of ground-source heat-pump (GSHP) heat supply systems are presented. The new model blocks take into account the effect the freezing of porous moisture in soil has on the GSHP system performance efficiency. Illustration is given to the need of taking into account the porous moisture freezing/thawing processes in soil, and the results from investigations devoted to the opening possibilities of constructing adaptive GSHP systems with controlled intensity of heat transfer in the soil-thermal well system are presented. The development of software simulating the porous moisture phase state variation processes in soil was preceded by development of mathematical equations representing the thermal conditions of soil body involving porous moisture freezing/thawing processes. A description of these equations is also given in the article. In constructing the mathematical model, the notion "effective thermal conductivity" of soil was introduced for taking into account the latent heat of phase transition that releases during the freezing of moisture. The above-mentioned effective thermal conductivity of soil involves two components: the soil thermal conductivity coefficient itself and an additional term modifying the thermal conductivity value for taking into account the influence of phase transition. For quantitatively evaluating the soil effective thermal conductivity component that takes into account the influence of phase transition, the soil freezing zone radius around the thermal well was determined. The obtained analytic solutions have been implemented in the form of computer program blocks, after which a "numerical experiment" was carried out for estimating the effect the porous moisture freezing/thawing processes have on the soil thermal conditions. It was demonstrated during that experiment that the soil thermal conductivities determined

  14. Study on Optimizing Thermal Energy Storage Capacity for Heat Supply System

    Institute of Scientific and Technical Information of China (English)

    曹家枞

    2001-01-01

    Thermal energy storage (TES) can increase the energetic efficiencies and, in many cases, the exergetic efficiencies of thermal energy systems. Steam boiler plant with a violently fluctuating load is a typical example when a steam accumulator is added to it. While the conparatively big first cost constitutes a barrier to the wide use of TES, the cost will notably be reduced through minimizing the necessary thermal capacity of it JThe structure and illustrations are given for the computer program designed for performing the optimization. This'program was applied to an existing boiler plant equipped with a steam accumulator. The results show that there would have been a big reduction in the necessary capacity, if the design of this steam accumulator had been optimized. Four conclusions have been reached.

  15. Research of the heat exchanging processes running in the heating and hot water supply loops of the coil heat exchangers

    Directory of Open Access Journals (Sweden)

    Ірина Геннадіївна Шитікова

    2016-11-01

    Full Text Available The fuel-energy complex research has made it possible to disclose a huge power-saving potential in the municipal heat-and-power engineering. Power-and-resource-saving units and systems are becoming extremely urgent because of the power engineering crisis expansion. The self-adjusting heat supply system from the individual heating points with the heat-accumulating units and coil heat exchangers for independent heating and water supply systems has been examined. Coil heat exchangers are used in municipal heating for heat transfer (e.g. geothermal waters for the independent mains of the heating and hot water supply systems. The heat engineering calculation of the heating and accumulating unit with the coil heat exchanger for independent heat supply systems from individual heater was performed and experimental data were received at the experimental industrial unit under the laboratory conditions. The peculiarities of the flows in the intertubular space, their influence on the heat exchange and temperatures of the first and intermediate mains have been shown. It is important to know the processes running inside the apparatus to be able to improve the technical characteristics of the three-loop coil heat exchanger. The task solution will make it possible to save the materials consumption for the three-loop coil heat exchangers in the future

  16. Energy and Economic Efficiency of Gas Turbine Units and Heat Pumps in Power-supply Systems in the Arctic Regions of Russia

    Directory of Open Access Journals (Sweden)

    Suvorov D.M.

    2017-04-01

    Full Text Available Currently, in publications, there is some controversy about the efficiency of various power-supply systems operating in extreme climatic conditions. The need to dispel this controversy explains this study's relevance. The purpose of this study is to evaluate the feasibility of the use of cogeneration gas turbine and microturbine units as the heat-and-power source for a camp-like residential facility in the Arctic regions of Russia. A boiler plant and a heat pump system are analyzed as heat sources for the afore-mentioned camp. The authors used their own mathematical models of the units to do the study. The estimates were based on the annual facility-specific power and heat consumption data, additionally climatic conditions and fuel kind (natural gas were taken into consideration. The study resulted in defining the plants' limits of equal fuel consumption, depending on the substituted power output efficiency and the power/heat production cost to the price of gas correlation. Another result was the evaluation of the power efficiency (by the natural gas consumption and economic feasibility, as well as the payback term. We concluded that in case the natural gas was the only fuel available the ground source vapor-compressing heat pump systems were power-wise and economically unsound, provided they were operated under environmental conditions typical for the Russian North and according to the region-specific heat-supply schedule. The outcome of this study can be used when planning/designing the power-supply facilities in extreme climatic conditions, as well as in evaluating/estimating the power-supply systems' efficiency.

  17. Objective function for municipal heat supply systems’ structural optimization

    Directory of Open Access Journals (Sweden)

    Sergiy V. Babich

    2015-03-01

    Full Text Available Modern heat supply systems in urban areas have the potential to heat supply cost reduction when using various alternative thermal energy sources. Availability of possible alternatives allows to select the source that generates a cheaper heat. At that arises the question of expressing such different sources’ characteristics as capital cost, reliability and efficiency in the consistent measurement units. This paper proposes an objective function representing all the factors affecting the thermal energy final cost in monetary units. It is shown that depending on external factors the range of prime cost for heat from various sources does vary considerably. Expected is that the proposed objective function application for managing the heat supply systems structure in urban areas will significantly reduce the operating costs.

  18. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    OpenAIRE

    Bolonina Alona; Bolonins Genadijs; Blumberga Dagnija

    2014-01-01

    District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with redu...

  19. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Sudhagar [University of Georgia; Sokhansanj, Shahabaddine [ORNL; Togore, Sam [U.S. Department of Energy; Turhollow Jr, Anthony F [ORNL

    2010-03-01

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam3). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery.

  20. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 2: Cost of heat and power generation systems

    Energy Technology Data Exchange (ETDEWEB)

    Mani, S. [Biological and Agricultural Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602 (United States); Sokhansanj, S.; Turhollow, A.F. [Environmental Sciences Division, Oak Ridge National Laboratory, P. O. Box 2008, Oak Ridge, TN 37831 (United States); Tagore, S. [Office of Biomass Program, U.S. Department of Energy, Washington, DC 20585 (United States)

    2010-03-15

    This paper presents a techno-economic analysis of corn stover fired process heating (PH) and the combined heat and power (CHP) generation systems for a typical corn ethanol plant (ethanol production capacity of 170 dam{sup 3}). Discounted cash flow method was used to estimate both the capital and operating costs of each system and compared with the existing natural gas fired heating system. Environmental impact assessment of using corn stover, coal and natural gas in the heat and/or power generation systems was also evaluated. Coal fired process heating (PH) system had the lowest annual operating cost due to the low fuel cost, but had the highest environmental and human toxicity impacts. The proposed combined heat and power (CHP) generation system required about 137 Gg of corn stover to generate 9.5 MW of electricity and 52.3 MW of process heat with an overall CHP efficiency of 83.3%. Stover fired CHP system would generate an annual savings of 3.6 M$ with an payback period of 6 y. Economics of the coal fired CHP system was very attractive compared to the stover fired CHP system due to lower fuel cost. But the greenhouse gas emissions per Mg of fuel for the coal fired CHP system was 32 times higher than that of stover fired CHP system. Corn stover fired heat and power generation system for a corn ethanol plant can improve the net energy balance and add environmental benefits to the corn to ethanol biorefinery. (author)

  1. Analysis of the Impact of Decreasing District Heating Supply Temperature on Combined Heat and Power Plant Operation

    Directory of Open Access Journals (Sweden)

    Bolonina Alona

    2014-12-01

    Full Text Available District heating systems are widely used to supply heat to different groups of heat consumers. The district heating system offers great opportunities for combined heat and power production. In this paper decreasing district heating supply temperature is analysed in the context of combined heat and power plant operation. A mathematical model of a CHP plant is developed using both empirical and theoretical equations. The model is used for analysis of modified CHP plant operation modes with reduced district heating supply temperature. Conclusions on the benefits of new operation modes are introduced.

  2. Energy efficiency by use of automated energy-saving windows with heat-reflective screens and solar battery for power supply systems of European and Russian buildings

    Science.gov (United States)

    Zakharov, V. M.; Smirnov, N. N.; Tyutikov, V. V.; Flament, B.

    2015-10-01

    The new energy saving windows with heat-reflecting shields have been developed, and for their practical use they need to be integrated into the automated system for controlling heat supply in buildings and the efficiency of their use together with the existing energy-saving measures must be determined. The study was based on the results of field tests of windows with heat-reflective shields in a certified climate chamber. The method to determine the minimum indoor air temperature under standby heating using heat-reflective shields in the windows and multifunctional energy-efficient shutter with solar battery have been developed. Annual energy saving for the conditions of different regions of Russia and France was determined. Using windows with heat-reflecting screens and a solar battery results in a triple power effect: reduced heat losses during the heating season due to increased window resistance; lower cost of heating buildings due to lowering of indoor ambient temperature; also electric power generation.

  3. Water chemistry in heat and cold supply (district heating/cooling)

    Energy Technology Data Exchange (ETDEWEB)

    Deelen-Bremer, Marga van; Vos, Frank de; Heijboer, Rob [KEMA Nederland B.V. (Netherlands)

    2010-07-01

    District heating is seen as an important pillar in the CO{sub 2} reduction. Since the Kyoto protocol with the target for reduction of greenhouse gases, a renewed interest in district heating is visible. District heating and increasingly district cooling can be used for heating/cooling of houses, but also for large buildings and greenhouses. Combined heat and power (CHP), waste incinerator, but also rest heat of industry can provide the heat for district heating. On the other hand cold surface water, groundwater, but also rest heat can be used for district cooling. With the growing heat/cold supply market, also an even larger growth in cases of damages in district heating systems is wittnessed. Damages were chemistry can play an preventing role. A good conditioning of the district heating water, combined with proper monitoring, will safeguard the integrity of the system. (orig.)

  4. District Heating System Using Heat Pump Installations and CHP

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2015-12-01

    Full Text Available The article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating puThe article describes the district heating system, in which part of the heat of return water thermal power is used to supply heat to the district heating pumps, evaporators heating and hot water. Heat pumps use carbon dioxide as refrigerant. During the transitional period of the year, and the summer heat pump for preparing hot-water supply system uses the heat of the surrounding air. The heat of the ambient air is used in the intermediate heat exchanger between the first and second stages of the heat pump to cool the gas after the first stage of the compressor of the heat pump.

  5. Integration of space heating and hot water supply in low temperature district heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2016-01-01

    is required by the consumer. We study conventional district heating at different temperatures and compare the energy and exergetic efficiency and annual heating cost to solutions that utilize electricity for supplementary heating of domestic hot water in low temperature district heating. This includes direct...... electric heating and three heat pump solutions applying R134a and R744. The results show that conventional solutions at lowest possible temperature have the highest exergetic efficiency of 28% and lowest annual cost of € 690 for a 159 m2 house. The best low temperature system is an R134a heat pump with hot......District heating may supply many consumers efficiently, but the heat loss from the pipes to the ground is a challenge. The heat loss may be lowered by decreasing the network temperatures for which reason low temperature networks are proposed for future district heating. The heating demand...

  6. Heat supply planning for the ecological housing community Munksøgård

    DEFF Research Database (Denmark)

    Karlsson, Kenneth Bernard; Petrovic, Stefan; Næraa, Rikke

    2015-01-01

    Munksøgård is a housing community near the city of Roskilde, Denmark. In 2014, Munksøgård's residents have agreed to change the existing heat supply system. The choice of future heat supply was narrowed to heat pumps, new biomass boiler and connection to nearby district heating network. The prese...

  7. Reconstruction of Low Pressure Gas Supply System

    Directory of Open Access Journals (Sweden)

    S. N. Osipov

    2013-01-01

    Full Text Available The current reconstruction of residential areas in large cities especially with the developed heat-supply systems from thermal power stations and reduction of heat consumption for heating due to higher thermal resistance of building enclosing structures requires new technical solutions in respect of gas-supply problems. While making reconstruction of a gas-supply system of the modernized or new buildings in the operating zone of one gas-distribution plant it is necessary to change hot water-supply systems from gas direct-flow water heaters to centralized heat-supply and free gas volumes are to be used for other needs or gas-supply of new buildings with the current external gas distribution network.Selection of additional gas-line sections and points of gas-supply systems pertaining to new and reconstructed buildings for their connection to the current distribution system of gas-supply is to be executed in accordance with the presented methodology.

  8. Energetic retrofitting of industrial heat supply systems. Possibilities of enhancing the efficiency and energy conservation at large combustion engineering plants; Energetische Modernisierung industrieller Waermeversorgungssysteme. Moeglichkeiten der Effizienzsteigerung und der Energieeinsparung an grossen feuerungstechnischen Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-12-15

    In the contribution under consideration, the Deutsche Energie-Agentur GmbH (Berlin, Federal Republic of Germany) reports on an energetic modernization of industrial heat supply systems. Possibilities of an enhancement of the energetic efficiency and energy conservation at large combustion engineering plants are described. After an introduction to this theme, the author of this contribution provides an overview of the optimization of heat supply systems, and reports on the following aspects: Optimisation of the heat demand; energy efficient heat generation; heat recovery; energy efficient conversion technology and generation technology; associate partners for more energy efficiency in industry and commerce; best practice examples.

  9. Energy and cost management in district heat supply to heating and freshwater treatment systems; Energie- und Kostenmanagement bei der Fernwaerme-Versorgung fuer Heizungs- und Trinkwarmwasserbereitungs (TWWB)-Anlagen

    Energy Technology Data Exchange (ETDEWEB)

    Hesse, W.

    2001-07-01

    System optimisation comprises the following stages: Calculation of the rated heat consumption - optimisation of system parameters - improvement of control circuit stability -, all of which are engineering tasks. Optimisation of the supply concept in consideration of the supply cost structure (holistic approach) is another engineering task. [German] Erfahrungen haben gezeigt, dass in der Betriebsfuehrung von Heizungs- und -TWWB-Anlagen Verbesserungspotentiale im Sinne einer Energie- und Kosteneinsparung vorhanden sind. Die Anlagenoptimierung beinhaltet die Komplexe: - Ermittlung des Nennwaermeverbrauchs, - optimale Einstellung der Anlagenparameter, - Verbesserung der Regelkreisstabilitaet, - und kann ueberwiegend durch Ingenieurleistungen durchgefuehrt werden. Ebenfalls durch Ingenieurleistungen kann das Versorgungskonzept bei Beachtung der Struktur der Versorgungskosten optimiert werden (ganzheitliche Betrachtung). (orig.)

  10. Integration of space heating and hot water supply in low temperature district heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2016-01-01

    electric heating and three heat pump solutions applying R134a and R744. The results show that conventional solutions at lowest possible temperature have the highest exergetic efficiency of 28% and lowest annual cost of € 690 for a 159 m2 house. The best low temperature system is an R134a heat pump with hot......District heating may supply many consumers efficiently, but the heat loss from the pipes to the ground is a challenge. The heat loss may be lowered by decreasing the network temperatures for which reason low temperature networks are proposed for future district heating. The heating demand...... of the consumers involves both domestic hot water and space heating. Space heating may be provided at low temperature in low energy buildings. Domestic hot water, however, needs sufficient temperatures to avoid growth of legionella. If the network temperature is below the demand temperature, supplementary heating...

  11. Proposal for the award of a contract for the design, supply, installation and commissioning of a Heating, Ventilation and Air-Conditioning (HVAC) system for the computer room of the CERN Control Centre

    CERN Document Server

    2012-01-01

    Proposal for the award of a contract for the design, supply, installation and commissioning of a Heating, Ventilation and Air-Conditioning (HVAC) system for the computer room of the CERN Control Centre

  12. 某图书馆暖通空调系统设计分析%On heat-supply and ventilation air-conditioner system of some library

    Institute of Scientific and Technical Information of China (English)

    王秀山

    2016-01-01

    According to the design ideas for the library,from heat-supply and ventilation air-conditioner system,cold and heat source system,in-terior layout,professional cooperation and other aspects,the paper analyzes a series of problems in the heat-supply and ventilation air-conditioner of some library,and illustrates respective treatment measures,so as to create the comfortable reading environment with suitable temperature and humidity.%根据图书馆的设计理念,从暖通空调系统、冷热源系统、室内系统布置、专业配合等方面,分析了某图书馆暖通空调设计中存在的一系列问题,并阐述了相应的处理措施,旨在创造出温湿度适宜、环境清新的阅读环境.

  13. Residential solar-heating system

    Science.gov (United States)

    1978-01-01

    Complete residential solar-heating and hot-water system, when installed in highly-insulated energy-saver home, can supply large percentage of total energy demand for space heating and domestic hot water. System which uses water-heating energy storage can be scaled to meet requirements of building in which it is installed.

  14. A 25 kW, 25 kHz Induction Heating Power Supply for MOVPE System Using L-LC Resonant Inverter

    Directory of Open Access Journals (Sweden)

    Mangesh Borage

    2013-01-01

    Full Text Available A topology named L-LC resonant inverter (RI for induction heating (IH applications takes most of the merits of the conventional series and parallel resonant schemes, while eliminating their limitations. In this paper, fundamental frequency AC analysis of L-LC RI is revisited, and a new operating point is suggested featuring enhanced current gain and near in-phase operation as compared to the conventional operating point. An approximate analysis of the circuit with square-wave voltage source is also described highlighting the effect of auxiliary inductor on the source current waveform. The analysis also leads to an optimum choice of the auxiliary inductance. The requirements of the metal organic vapour phase epitaxy (MOVPE system in which a graphite susceptor is required to be heated to 1200°C demanding a 25 kW, 25 kHz IH power supply, the configuration of developed IH system, and experimental results are presented.

  15. Participatory Demand-supply Systems

    NARCIS (Netherlands)

    Rezaee, S.A.; Oey, M.A.; Nevejan, C.I.M.; Brazier, F.M.

    2015-01-01

    Introducing the notion of Participatory Demand-Supply (PDS) systems as socio-technical systems, this paper focuses on a new approach to coordinating demand and supply in dynamic environments. A participatory approach to demand and supply provides a new frame of reference for system design, for which

  16. Participatory Demand-supply Systems

    NARCIS (Netherlands)

    Rezaee, S.A.; Oey, M.A.; Nevejan, C.I.M.; Brazier, F.M.

    2015-01-01

    Introducing the notion of Participatory Demand-Supply (PDS) systems as socio-technical systems, this paper focuses on a new approach to coordinating demand and supply in dynamic environments. A participatory approach to demand and supply provides a new frame of reference for system design, for which

  17. MULTI-HEAT SOURCE SOLAR HEAT PUMP HEAT SUPPLY SYSTEM AND PERFORMANCE SIMULATION%复合热源太阳能热泵供热系统及其性能模拟

    Institute of Scientific and Technical Information of China (English)

    杨磊; 张小松

    2011-01-01

    提出了一种复合热源太阳能热泵供热系统,通过阀门切换,可根据不同的天气状况改变运行模式,以空气和太阳辐射作为热源制取供暖用水.针对所设计的lOkw供热系统,建立了系统的数学模型,对热泵串联集热器(SC+HP)及集热器串联热泵(HP+SC)两种运行模式下的循环性能进行了计算机模拟分析,并计算了系统的全年运行状况.从模拟结果可以看出,在模拟进水温度区间内,HP+SC模式下热泵COP较高,最高比SC+HP模式高2.58%;而SC+HP模式集热器热性能较好,总热效率更高,最高比HP+SC模式高2.62%.%A compound solar heat pump heat supply system was presented. The system can make heating water from air source and solar radiation by valve switching, based on different weather conditions. A numerical model for a l0kW heating utilizing was established. The circulation performances of solar collector with heat pump( SC + HP) and heat pump with solar collector( Hp + SC) operation modes were simulated. The all year round operation status was also caculated.The results have shown that the COP of HP + SC mode is at most 2.58 % higher than SC + HP mode in simulation water temperature range. But the latter has a better collector thermal performance and overall thermal efficiency is at most 2.62 % higher than the former.

  18. Analysis of heat transfer in portable power supply

    Science.gov (United States)

    Abdullah, Mohd Azman; Ali, Ahmad Nazrin

    2016-03-01

    Portable power supply (PPS) is developed based on the necessity in supplying instant power to support domestic appliances during power shortage or in remote area. In this paper, the heat transfer inside the PPS is analyzed and demonstrated by temperature change during battery charging and discharging. The computational fluid dynamic (CFD) model of the PPS battery and housing are developed. The heat flow inside the PPS is studied at different conditions of battery and air flows. The increment of the temperature inside the PPS could cause the PPS system to damage and unsafe. Few elements are manipulated for the study, such as battery positions, holedimensions and fan models in order toimprove the design of PPS. Experimental approach is also conducted to validate the temperature and heat transfer in the PPS.

  19. Optics Supply Planning System

    Energy Technology Data Exchange (ETDEWEB)

    Gaylord, J

    2009-04-30

    The purpose of this study is to specify the design for an initial optics supply planning system for NIF, and to present quality assurance and test plans for the construction of the system as specified. The National Ignition Facility (NIF) is a large laser facility that is just starting operations. Thousands of specialized optics are required to operate the laser, and must be exchanged over time based on the laser shot plan and predictions of damage. Careful planning and tracking of optic exchanges is necessary because of the tight inventory of spare optics, and the long lead times for optics procurements and production changes. Automated inventory forecasting and production planning tools are required to replace existing manual processes. The optics groups members who are expected to use the supply planning system are the stakeholders for this project, and are divided into three groups. Each of these groups participated in a requirements specification that was used to develop this design. (1) Optics Management--These are the top level stakeholdersk, and the final decision makers. This group is the interface to shot operations, is ultimately responsible for optics supply, and decides which exchanges will be made. (2) Work Center Managers--This group manages the on site optics processing work centers. They schedule the daily work center operations, and are responsible for developing long term processing, equipment, and staffing plans. (3) Component Engineers--This group manages the vendor contracts for the manufacture of new optics and the off site rework of existing optics. They are responsible for sourcing vendors, negotiating contracts, and managing vendor processes. The scope of this analysis is to describe the structure and design details of a system that will meet all requirements that were described by stakeholders and documented in the analysis model for this project. The design specifies the architecture, components, interfaces, and data stores of the system

  20. Sustainable Biomass Supply Systems

    Energy Technology Data Exchange (ETDEWEB)

    Erin Searcy; Dave Muth; Erin Wilkerson; Shahab Sokansanj; Bryan Jenkins; Peter Titman; Nathan Parker; Quinn Hart; Richard Nelson

    2009-04-01

    The U.S. Department of Energy (DOE) aims to displace 30% of the 2004 gasoline use (60 billion gal/yr) with biofuels by 2030 as outlined in the Energy Independence and Security Act of 2007, which will require 700 million tons of biomass to be sustainably delivered to biorefineries annually. Lignocellulosic biomass will make an important contribution towards meeting DOE’s ethanol production goals. For the biofuels industry to be an economically viable enterprise, the feedstock supply system (i.e., moving the biomass from the field to the refinery) cannot contribute more that 30% of the total cost of the biofuel production. The Idaho National Laboratory in collaboration with Oak Ridge National Laboratory, University of California, Davis and Kansas State University are developing a set of tools for identifying economical, sustainable feedstocks on a regional basis based on biorefinery siting.

  1. IMPROVEMENT OF SYSTEMS OF TECHNICAL WATER SUPPLY WITH COOLING TOWERS FOR HEAT POWER PLANTS TECHNICAL AND ECONOMIC INDICATORS PERFECTION. Part 2

    Directory of Open Access Journals (Sweden)

    Yu. A. Zenovich-Leshkevich-Olpinskiy

    2016-01-01

    Full Text Available The method of calculation of economic efficiency that can be universal and is suitable for feasibility study of modernization of irrigation and water distribution system of cooling towers has been developed. The method takes into account the effect of lower pressure exhaust steam in the condenser by lowering the temperature of the cooling water outlet of a cooling tower that aims at improvement of technical and economic indicators of heat power plants. The practical results of the modernization of irrigation and water distribution system of a cooling tower are presented. As a result, the application of new irrigation and water distribution systems of cooling towers will make it possible to increase the cooling efficiency by more than 4 оС and, therefore, to obtain the fuel savings by improving the vacuum in the turbine condensers. In addition, the available capacity of CHP in the summer period is increased. The results of the work, the experience of modernization of irrigation and water distribution systems of the Gomel CHP-2 cooling towers system, as well as the and methods of calculating of its efficiency can be disseminated for upgrading similar facilities at the power plants of the Belarusian energy system. Some measures are prosed to improve recycling systems, cooling towers and their structures; such measures might significantly improve the reliability and efficiency of technical water supply systems of heat power plants.

  2. Restoration of the plasma discharge during density limit disruptions in the T-10 tokamak using electron cyclotron heating and ohmic power supply system

    Science.gov (United States)

    Savrukhin, P. V.; Shestakov, E. A.

    2016-11-01

    Experiments in the T-10 tokamak [Alikaev et al., Plasma Phys. Controlled Fusion 30, 381 (1988)] have demonstrated the possibility of control of the plasma current and prevention of formation of the non-thermal (Eγ > 150 keV) electron beams after an energy quench at the density limit disruption using electron cyclotron heating (ECRH) and controlled operation of the Ohmic power supply system. Quasi-stable plasma operation with repetitive sawtooth oscillations can be restored after an energy quench using high auxiliary power Pec > 2-5 Poh. Optimal conditions of the plasma discharge recovery after an energy quench using auxiliary heating are identified. At high auxiliary power, restoration of the plasma discharge can be provided with the location of the EC resonance zone within the whole plasma cross section. The auxiliary power required for discharge restoration is minimal when the power is deposited around the m = 2, n = 1 magnetic island (here m and n poloidal and toroidal wave numbers). The threshold ECRH power increases linearly with plasma current. Prevention of the non-thermal electron beams during density limit disruption is associated with stabilization of bursts of the magnetohydrodynamic modes, creation of the saturated magnetic islands, and heating of the background plasma using ECRH. Plasma discharge recovery after an energy quench in a tokamak reactor using auxiliary heating and controllable reduction of the plasma current is discussed.

  3. Numerical Prediction of Flow and Heat Transfer on lubricant Supplying and Scavenging Flow Path of an Aero-Engine Lubrication System

    Science.gov (United States)

    Huang, S. Q.; Liu, Z. X.; Lv, Y. G.; Zhang, L. F.; Xu, T.

    This paper presents a numerical model of internal flows on lubricant supplying and scavenging flow path of an aero-engine lubrication system. The numerical model was built in the General Analysis Software of Aero-engine Lubrication System (GASLS), developed by Northwestern Polytechnical University. The lubricant flow flux, pressure and temperature distribution at steady state were calculated. GASLS is a general purpose computer program employed a ID steady state network algorithm for analyzing flowrates, pressures and temperatures in a complex flow network. All kinds of aero-engine lubrication systems can be divided into finite correlative typical elements and nodes from which the calculation network is developed in GASLS. Special emphasis is put on how to use combinational elements which is a type of typical elements to replace some complex components such as bearing compartments, accessory drive gearboxes or heat exchangers. This method can reduce network complexity and improve calculation efficiency. The computational results show good agreement with experimental data.

  4. Model-based control of district heating supply temperature

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, Linn

    2010-11-15

    A model-based control strategy for the supply temperature to a district heating network was tested during three weeks at Idbaecken's CHP plant. The aim was to increase the electricity efficiency by a lower supply temperature, without risking the delivery reliability of heat to the district heating customers. Simulations and tests showed that at high loads, the mean supply temperature could be reduced by 4 deg C and the electricity production could be increased by 2.5%

  5. A Direct Heat Exchanger Unit used for Domestic Hot Water Supply in a Single-family House Supplied by Low Energy District Heating

    DEFF Research Database (Denmark)

    Brand, Marek; Thorsen, Jan Eric; Svendsen, Svend

    2010-01-01

    on the testing of the dynamic behaviour of an Instantaneous Heat Exchanger Unit(IHEU) designed for DHW heating and space heating in detached family houses supplied by LEDH ensuring an entry-to-substation temperature of 51 °C. We measured the time it takes for the IHEU to produce DHW with a temperature of 42 °C......The increasing number of new and renovated buildings with reduced heating requirements will soon make traditional District Heating (DH) systems uneconomic. To keep DH competitive in the future, the heat loss in DH networks needs to be reduced. One option is to reduce the supply temperature of DH...... as much as possible. This requires a review of the behaviour of the whole domestic hot water (DHW) supply system with focus on the user comfort and overall costs. This paper describes some practical approaches to the implementation of this Low Energy District Heating (LEDH) concept. It reports...

  6. Investigation of the feasibility of the solar-/geothermally-assisted heat supply system Gesotherm S; Untersuchung der Durchfuehrbarkeit des solar-/ geothermisch gestuetzten Waermeversorgungssystems Gesotherm S

    Energy Technology Data Exchange (ETDEWEB)

    Liebisch, H. [EKT Energie und Kommunal-Technologie GmbH, Berlin (Germany)

    1998-12-31

    The project has been running since 1st March 1998 and is supposed to investigate the technical feasibility and economic efficiency of the Gesotherm S heat supply system in the residential area Berlin-Biesdorf/Habichtshorst (1,000 flats). Main points of investigation are: proof of feasibility and geothermal analysis of the deep pit; analysis of storage possibilities and technical synergies of combined solar-geothermal operation; determination of the regenerative supply ratio; calculation of economic efficiency; estimation of cost-saving potentials. The whole system is simulated for these studies. A new simulation model was developed for the pit. Simulations are based on the SMILE-simulation environment developed by the Technical University of Berlin. First estimates indicate costs of DM 200 per MWh without subsidies. (orig.) [Deutsch] Mit dem seit 1. Maerz 1998 laufenden Vorhaben soll die technische Realisierbarkeit und wirtschaftliche Attraktivitaet des Waermeversorgungssystems Gesotherm S am Beispiel der Nahwaermeversorgung eines Wohngebietes (ca. 1.000 WE) in Berlin-Biesdorf/Habichtshorst umfassend untersucht werden. Schwerpunkte der Untersuchung: - Machbarkeitsnachweis und geothermische Analyse der Tiefensonde - Analyse der Speichermoeglichkeiten und der technischen Synergieeffekte des solar-/geothermischen Kombinationsbetriebes - Ermittlung der regenerativen Deckungsrate - Berechnung der Wirtschaftlichkeit - Abschaetzung der Kostensenkungspotentiale. Fuer die Untersuchung wird das Gesamtsystem simuliert. Speziell fuer die Tiefensonde wird ein neues Simulationsmodell entwickelt. Basis ist die, an der TU-Berlin entwickelte, Simulationsumgebung SMILE. Erste Abschaetzungen ergaben Waermekosten ohne Subventionen von unter 200 DM/MWh. (orig.)

  7. Optimal usage of low temperature heat sources to supply district heating by heat pumps

    DEFF Research Database (Denmark)

    Pieper, Henrik; Ommen, Torben Schmidt; Markussen, Wiebke Brix

    2017-01-01

    This paper presents a theoretical study on the optimal usage of different low temperature heat sources to supply district heating by heat pumps. The study is based on data for the Copenhagen region. The heat sources were prioritized based on the coefficient of performance calculated for each hour....... Groundwater, seawater and air heat sources were compared with each other as well as to a scenario consisting of a combination of these heat sources. In addition, base load and peak load units were included. Characteristic parameters were the coefficient of performance, the number of full load hours...

  8. Absorption-heat-pump system

    Science.gov (United States)

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  9. A Policy study on stabilization of heating oil supply and demand

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Bok Jae [Korea Energy Economics Institute, Euiwang (Korea)

    1999-03-01

    As a principal heating fuel for household and commercial sector, and a heat source fuel for industry, the heating oil shows its great demand intensively during a specific period (wintertime) due to its characteristics. It represents that the fluctuation of heating oil demand throughout the year is very extreme. Therefore, the stable supply of heating oil has been rising as an important task. It is desirable to develop and supply a new type of heating oil compounded of kerosene and gasoline with appropriate ratio for short- and mid-term to have a stable supply and demand of heating oil. For long-term prospect, it is desirable to supply petroleum products mixing gasoline and B-C oil as heating oil when it is equipped with combustion technology of boiler and distribution system. In this case, it is required to have investment on infrastructure for the supply of new heating oil (mixture of gasoline and B-C oil) and a proper preparatory period for the conversion of equipment (such as a boiler). The vitalization of storing oil is essential to stabilize the supply and demand of heating oil. In order to vitalize it, the price of heating oil should be determined by a market function reflecting the seasonal supply and demand circumstances. (author). 101 refs., 5 figs., 83 tabs.

  10. APPLICATION OF UNIT CONSUMPTION ANALYSIS IN THE 200 MW HEAT-SUPPLYING SYSTEM OF ZHENGZHOU COGENERATION PLANT%单耗分析理论在郑州热电厂200 MW供热系统中的应用

    Institute of Scientific and Technical Information of China (English)

    尚玉琴; 曹智; 宋之平

    2001-01-01

    在整理“供热系统”单耗分析的基础上,完善了热电联产供热系统的单耗计算方法,确定了热电联产供热系统各环节火 用效率的计算式,提出了一种确定供热系统设备折旧费的方法。利用单耗分析理论,对郑州热电厂出厂处及热用户处的供热煤耗和成本进行了计算和分析。%On the basis of collating the unit consumption analysis data of heat-supplying system,a formula to compute exergy-efficiency of each segment in heat-supplying system of a cogeneration plant has been deduced,the calculation method of electric and heat unit consumption being perfected,a method for determining the depreciation charge of equipments in heat-supplying system being presented,By using the unit consumption theory,the coal consumption and production cost of heat-supplying at the energy-outgoing point from Zhengzhou Cogeneration Plant and at the end of heat users have been calculated and analyzed.

  11. Public Water Supply Systems (PWS)

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset includes boundaries for most public water supply systems (PWS) in Kansas (525 municipalities, 289 rural water districts and 13 public wholesale water...

  12. Installation of potable water supply and heat supply at base of subsoil water

    Directory of Open Access Journals (Sweden)

    Denysova Alla Evseevna

    2016-01-01

    Full Text Available Removal of groundwater with further use of it for potable water supply and heat supply with the use of heat pump is an important problem. A new revolutionary approach to the decision of energy and water saving that provides rational accommodation of groundwater boreholes ensuring the required flow rate of water through the heat pump evaporator with simultaneously high intensity of heat exchange process is proposed. The method of calculation which allows determining the necessary depth of borehole, quantity of boreholes, in consideration of flow rate and temperature of subsoil water determining capacity of heat pump installation is worked out.

  13. Installation of potable water supply and heat supply at base of subsoil water

    Directory of Open Access Journals (Sweden)

    Denysova Alla Evseevna

    2016-01-01

    Full Text Available Removal of groundwater with further use of it for potable water supply and heat supply with the use of heat pump is an important problem. A new revolutionary approach to the decision of energy and water saving that provides rational accommodation of groundwater boreholes ensuring the required flow rate of water through the heat pump evaporator with simultaneously high intensity of heat exchange process is proposed. The method of calculation which allows determining the necessary depth of borehole, quantity of boreholes, in consideration of flow rate and temperature of subsoil water determining capacity of heat pump installation is worked out.

  14. Minimizing costs is easier than minimizing peaks when supplying the heat demand of a group of houses

    NARCIS (Netherlands)

    Fink, Jiří; Hurink, Johann L.

    2015-01-01

    This paper studies planning problems for a group of heating systems which supply the hot water demand for domestic use in houses. These systems (e.g. gas or electric boilers, heat pumps or microCHPs) use an external energy source to heat up water and store this hot water for supplying the domestic d

  15. Heat supply planning for the ecological housing community Munksøgård

    DEFF Research Database (Denmark)

    Karlsson, Kenneth Bernard; Petrovic, Stefan; Næraa, Rikke

    2015-01-01

    Munksøgård is a housing community near the city of Roskilde, Denmark. In 2014, Munksøgård's residents have agreed to change the existing heat supply system. The choice of future heat supply was narrowed to heat pumps, new biomass boiler and connection to nearby district heating network. The present...... paper compares results from techno-economic energy system analysis, simple private-economic analysis and assessment of externalities related to the heat supply and discusses the differences in conclusions - is the economic optimal solution different from a system or private-economic point of view......? The techno-economic energy system analysis is done using TIMES-DTU model, which optimizes over all sectors in Denmark and all periods until 2050. The result from this model gives the least expensive solution from the overall system point of view. A spreadsheet model has been developed to do the private...

  16. Supply of domestic hot Water at comfortable temperatures by low-temperature district heating without risk of Legionella

    OpenAIRE

    Yang, Xiaochen; Svendsen, Svend; Li, Hongwei

    2016-01-01

    In Denmark, about 25% of the primary energy is consumed for covering the heat demand in the buildings. To achieve a complete renewable energy system by 2050, which is the goal set by the Danish government, methods that are more efficient and economical for heat supply are urgently needed. Considering the overall energy efficiency and environment effect, the district heating (DH) is a cost-effective way of supplying heat to high heat density area. Currently, the DH system in most countries are...

  17. On application of heating cable low-temperature radiation ground heat-supply system in projects%发热电缆低温辐射地面供暖系统在工程中的应用

    Institute of Scientific and Technical Information of China (English)

    杨立峰

    2016-01-01

    Combininf with the project at Licaiwanf Art Museum in Hufuan county,the paper introduces the features of the heatinf cable low-tem-perature radiation fround heat-supply system,illustrates its construction craft procedure and operation points,and points out the construction quality,safety and environment protection controllinf measures,so as to realize the maximum of the social and economic benefits.%结合壶关县李才旺美术馆工程实例,介绍了发热电缆低温辐射地面供暖系统的特点,并阐述了其施工工艺流程及操作要点,提出了施工质量、安全及保护控制措施,实现了社会经济效益的最大化。

  18. Development of a high-performance boiling heat exchanger by improved liquid supply to narrow channels.

    Science.gov (United States)

    Ohta, Haruhiko; Ohno, Toshiyuki; Hioki, Fumiaki; Shinmoto, Yasuhisa

    2004-11-01

    A two-phase flow loop is a promising method for application to thermal management systems for large-scale space platforms handling large amounts of energy. Boiling heat transfer reduces the size and weight of cold plates. The transportation of latent heat reduces the mass flow rate of working fluid and pump power. To develop compact heat exchangers for the removal of waste heat from electronic devices with high heat generation density, experiments on a method to increase the critical heat flux for a narrow heated channel between parallel heated and unheated plates were conducted. Fine grooves are machined on the heating surface in a transverse direction to the flow and liquid is supplied underneath flattened bubbles by the capillary pressure difference from auxiliary liquid channels separated by porous metal plates from the main heated channel. The critical heat flux values for the present heated channel structure are more than twice those for a flat surface at gap sizes 2 mm and 0.7 mm. The validity of the present structure with auxiliary liquid channels is confirmed by experiments in which the liquid supply to the grooves is interrupted. The increment in the critical heat flux compared to those for a flat surface takes a maximum value at a certain flow rate of liquid supply to the heated channel. The increment is expected to become larger when the length of the heated channel is increased and/or the gravity level is reduced.

  19. 集中空调冷凝热回收技术在生活热水供应系统中的应用%Application of central air conditioning condense heat recovery technology to domestic hot water supply system

    Institute of Scientific and Technical Information of China (English)

    黄璞洁; 李艳霞; 何耀炳; 许伊那

    2011-01-01

    介绍\t了空调冷凝热回收技术的工作原理,计算确定了冷凝热回收机组和蓄热水箱的容量,并与传统的空调和生活热水供应系统进行比较.探讨了空调冷凝热回收技术在生活热水供应系统中的设计应用.%Based on the working principle, calculates the capacity of the condense heat recovery unit and heat storage water tank, and compares with the traditional air conditioning and domestic hot water supply system. Discusses the application of air conditioning condense heat recovery technology to the design of domestic hot water supply system.

  20. Supply of domestic hot Water at comfortable temperatures by low-temperature district heating without risk of Legionella

    DEFF Research Database (Denmark)

    Yang, Xiaochen

    the potential of saving 13% heat loss compared to the decentralized substation system with bypass. The other form is to redirect the bypass flow to the bathroom heating during the non-heating season. With well insulated supply pipe, the bathroom heating flow can substitute for the bypass function......In Denmark, about 25% of the primary energy is consumed for covering the heat demand in the buildings. To achieve a complete renewable energy system by 2050, which is the goal set by the Danish government, methods that are more efficient and economical for heat supply are urgently needed....... Considering the overall energy efficiency and environment effect, the district heating (DH) is a cost-effective way of supplying heat to high heat density area. Currently, the DH system in most countries are still with supply and return temperature at 80/40 °C. The efficiency of the DH system can be improved...

  1. Estimation of efficiency of the heat supply system based on a boiler house and a wind turbine in the northern environment

    Science.gov (United States)

    Bezhan, A. V.; Minin, V. A.

    2017-03-01

    This article describes a methodological approach to defining indoor air temperature in buildings heated by a power supply unit consisting of a boiler house and a wind-driven power plant (WDPP). We discuss a heating option for a residential building in the windy conditions of Murmansk city. We proved that, during the periods of strong wind, a WDPP can partially or fully satisfy the heat demand and sometimes even create a surplus of energy. During low wind weather, almost all loads are handled by the boiler house. We considered a possibility to accumulate the surplus energy obtained from a WDPP during strong wind by increasing the temperature in the whole building up to 25°C and further using the accumulated heat during the lowwind period when indoor air temperature may fall below 20°C. This allows saving organic fuel in the boiler house. We demonstrated how indoor air temperature in the building may change throughout the year when using the surplus energy from the WDPP due to thermal storage capacitance of the building. We also provided the results of study, showing favorable energy-related effects of using a WDPP along with the boiler house. It was determined that engaging a WDPP in fulfilling the diagram of heating loads promotes the decrease in the boiler house's contribution to heat supply by 30 to 50%, and using the surplus energy from the WDPP and thermal storage capacitance of the building allows reducing the contribution of the boiler house by 5-15% more in certain months.

  2. Absorption heat pump system

    Science.gov (United States)

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  3. The conference of Russian Association of Engineers for Heating, Ventilation, Air-Conditioning, Heat Supply and Building Thermal Physics (ABOK

    Directory of Open Access Journals (Sweden)

    V.M. Yakubson

    2014-04-01

    Full Text Available On April, 11th, in Lenexpo the XVI conference of Russian Association of Engineers for Heating, Ventilation, Air-Conditioning, Heat Supply and Building Thermal Physics (ABOK “Effective HVAC and Heat Supply Systems” took place. There were a lot of presentations of new equipment for building systems and networks. All these reports were dedicated to the ways to make buildings more comfortable for people, to increase the energy efficiency, to reduce expenses and to improve the production efficiency. But besides the specific equipment, there were some reports dedicated to more general problems in design, installation and maintenance of building systems and networks

  4. Application of Frequency Conversion Constant Pressure Water Supply System in Heating Network%变频恒压补水系统在供暖热网中的应用

    Institute of Scientific and Technical Information of China (English)

    刘善顺

    2012-01-01

    随着人们对供暖质量和要求的不断提高,利用先进的自动化技术、控制技术以及通讯技术,设计出高性能、高节能、适应供暖复杂环境的恒压补水系统已成为必然趋势。朔里矿业对原工人村区域供热补水系统进行了改造,实现变频恒压自动补水系统,其节能效果显著,稳定性大大提高。本文阐述了供暖热网补水系统改造的背景、工作原理、控制方案、变频恒压补水系统的运行性能,并进行了经济效益分析。%With the increasing demanding on the heating quality, using advanced automation technology, control technology and communication technology, constant pressure water supply system with high performance, high energy-saving and adapting to the complex heating environment was designed, and it become an inevitable trend. Heating water supply system of the former district of workers was transformed by Shuoli Mining, realized variable frequency and constant pressure automatic water supply system, and saved energy observably, stability was greatly improved. The modification background, work theories and control programs of water supply system in heating network, and the operational performance of variable frequency and constant pressure water supply system were advanced in this paper, and economic benefits were analyzed.

  5. WATER SUPPLY SYSTEMS OPERATIONAL PROGNOSIS

    Directory of Open Access Journals (Sweden)

    Bruno Santos Vieira

    2016-12-01

    Full Text Available The actions planning to minimize risks and ensure the effectiveness of water supply systems requires the use of appropriate forecasting models. In fact, forecasting the behavior and analysis of future scenarios can be supported with the use of techniques and simulation models. In this article, we propose a procedure to simulate the actions of decision-makers in planning the operation of this system type in order to obtain an operating and financial prognosis that consider dynamic influences. The applicability of the proposed procedure is demonstrated through an urban systems planning problem of water supply. As a result we obtained a system costs distribution odds, which improves decision making in the context of the analyzed system. Additionally, the proposed procedure is applicable to other types of complex systems subject to dynamic influences.

  6. Water Supply Infrastructure System Surety

    Energy Technology Data Exchange (ETDEWEB)

    EKMAN,MARK E.; ISBELL,DARYL

    2000-01-06

    The executive branch of the United States government has acknowledged and identified threats to the water supply infrastructure of the United States. These threats include contamination of the water supply, aging infrastructure components, and malicious attack. Government recognition of the importance of providing safe, secure, and reliable water supplies has a historical precedence in the water works of the ancient Romans, who recognized the same basic threats to their water supply infrastructure the United States acknowledges today. System surety is the philosophy of ''designing for threats, planning for failure, and managing for success'' in system design and implementation. System surety is an alternative to traditional compliance-based approaches to safety, security, and reliability. Four types of surety are recognized: reactive surety; proactive surety, preventative surety; and fundamental, inherent surety. The five steps of the system surety approach can be used to establish the type of surety needed for the water infrastructure and the methods used to realize a sure water infrastructure. The benefit to the water industry of using the system surety approach to infrastructure design and assessment is a proactive approach to safety, security, and reliability for water transmission, treatment, distribution, and wastewater collection and treatment.

  7. Control technology in supply systems. Regelungstechnik in der Versorgungstechnik

    Energy Technology Data Exchange (ETDEWEB)

    Bach, H.; Baumgarth, S.; Forsch, K.; Reeker, J.; Krinninger, H.; Ruosch, E.; Schaefer, A.; Schiele, J.; Schroeder, H.; Treusch, W.

    1983-01-01

    The textbook presents the theoretical fundamentals and practical examples of control technology in supply systems. Practical examples of the fields of heating, air conditioning, and gas supply are presented in detail. The book comprises the following chapters: 1. Introduction to control technology; 2. steady state and time behaviour of control loop elements; 3. controlled systems; 4. control equipment; 5. control elements; 6. closed loops; 7. preset control; 8. meshed control loops; 9. digital control technology; 10. central control systems for supply systems of buildings; 11. examples of supply systems control.

  8. CRBRP decay heat removal systems

    Energy Technology Data Exchange (ETDEWEB)

    Hottel, R. E.; Louison, R.; Boardman, C. E.; Kiley, M. J.

    1977-01-01

    The Decay Heat Removal Systems for the Clinch River Breeder Reactor Plant (CRBRP) are designed to adequately remove sensible and decay heat from the reactor following normal shutdown, operational occurrences, and postulated accidents on both a short term and a long term basis. The Decay Heat Removal Systems are composed of the Main Heat Transport System, the Main Condenser and Feedwater System, the Steam Generator Auxiliary Heat Removal System (SGAHRS), and the Direct Heat Removal Service (DHRS). The overall design of the CRBRP Decay Heat Removal Systems and the operation under normal and off-normal conditions is examined. The redundancies of the system design, such as the four decay heat removal paths, the emergency diesel power supplies, and the auxiliary feedwater pumps, and the diversities of the design such as forced circulation/natural circulation and AC Power/DC Power are presented. In addition to overall design and system capabilities, the detailed designs for the Protected Air Cooled Condensers (PACC) and the Air Blast Heat Exchangers (ABHX) are presented.

  9. 利用混水直供系统优化一次网热量分配%Optimization of the Heating Distribution of Primary Network Through Mixing Water Directing Supply System

    Institute of Scientific and Technical Information of China (English)

    刘大磊

    2016-01-01

    低真空直供系统供暖半径大,暖气片与地暖住宅并存。为满足末端住宅的供暖要求,系统处在高温和大流量状态下运行,存在剩余热量而没有有效利用的情况。另外,城市的快速发展难与供暖主管网协调同步,在直供管网的末端规划新建了大量住宅小区,导致末端热源不足。为解决这种前端耗能过高和末端热源不足的状况,通过利用混水直供技术,优化低真空直供管网的整体热量分配,满足其他小区的供暖需求,同时,也节约出部分热量,增加新建住宅供暖面积。既消除管网末端热量不足问题,也解决了低真空直供系统末端所存在的水力失调问题。%Low vacuum directing supply system has a large heating radius, with the coexistence of radiators and radiant floor housing. In order to meet the requirements of the end residential heating, the system is operated at a high temperature and high flow state, without effective use of the remaining heat. In addition, primary heating network is not able to meet the heating demand of rapid urban housing development. In the areas covered by the end of mixing water directing supply network are planned to construct for more residential housing, which leads to a result that heat source of the end of this network is inadequate. For solving this unbalance state, high heat consumed in the start point of this network and inadequate heat supply in the end of this network, a technique of mixing water directing supply is adopted and heat distribution on low vacuum directing supply pipe network is optimized. Thus this improvement of mixing water directing supply provides the extra heat to meet the demand of other residential areas, hence also saves part of heat, and then increases the heating coverage of new residential area. Finally this improvement eliminates the insufficient heat at the end of pipe network, and solves the hydraulic imbalance at the end of low

  10. CO{sub 2}-neutral heat supply to residential areas. Pt. 1. Energy demand; CO{sub 2}-neutrale Waermeversorgung fuer Wohnsiedlungen. T. 1. Energiebedarf

    Energy Technology Data Exchange (ETDEWEB)

    Kuehl, L.; Schlosser, M.; Heuer, M.; Fisch, M.N. [Technische Univ. Braunschweig (Germany). Inst. fuer Gebaeude- und Solartechnik

    2006-11-15

    The contribution shows how integration of selected measures in heat supply (better thermal insulation, biomass fuel and solar technology) will result in an optimized heat supply system for the future which is characterized by low consumption and low emissions. (orig.)

  11. Minimax Analysis of Economic and Energy Efficiencies of Heat-Supply Pipelines

    Science.gov (United States)

    Sabdenov, K. O.

    2016-11-01

    A minimax problem of minimization of financial expenses and energy expenditure in a heat-supply system of buildings has been formulated and solved. The optimum parameters of a pipeline, i.e., the pipe radius and the thickness of the heat-insulating material, have been found.

  12. Mechanism of financial support in reforming the heat supply sphere: problems and prospects of improvement

    Directory of Open Access Journals (Sweden)

    Doroshenko, Valentina Viktorivna

    2012-11-01

    Full Text Available The problems of financial support for reforming the heat supply sphere arediscussed in the article. The current state of heat supply sphere causes aggravation of many socioeconomicproblems, connected with low quality, low reliability and excessive power consumption ofheat supply system. The main reason for this is the high level of depreciation of main funds at allstages of the production cycle – from production to consumption of heat energy. The currentlegislation defined the priority of modernization of heat supply sphere, but it requires the significantamount of financial resources for the implementation of relevant investment projects. Due to theanalysis the domestic sources of financial support are very limited, but the use of foreign fundsincreases the financial dependence on external borrowings. This situation provides a high relevance of searching for domestic funds and it became the main objective of this research. Thefinal goal was to make a set of suggestions on improving the current mechanism of financialsupport for reforming the heat supply sphere at the expense of implementation of reserve not beinginvolved nowadays, namely, public funds. People are eager and able to spend their own savings tointroduce the most effective modern energy saving technology – per-apartment heating. Accordingto the wide experience, this technology meets each person needs in heat with a significantreduction of natural gas consumption spent on heating (including solving the problem of energytariffs, budget funds for compensation benefits, subsidies, difference in fees, for finance investmentprojects, etc.

  13. Reduced heat stress in offices in the tropics using solar powered drying of the supply air.

    Science.gov (United States)

    Gunnarsen, L; Santos, A M B

    2002-12-01

    Many solutions to indoor climate problems known from developed countries may have prohibitive installation and running costs in developing countries. The purpose was to develop a low-cost solution to heat stress in a hot and humid environment based on solar powered drying of supply air. Dry supply air may facilitate personal cooling by increased evaporation of sweat. Heat acclimatized people with efficient sweating may in particular benefit from this cooling. A prototype solar powered supply system for dried-only air was made. Air from the system was mixed with room air, heated to six different combinations of temperature and humidity and led to Personal Units for Ventilation and Cooling (PUVAC) in six cubicles simulating office workplaces. A total of 123 heat acclimatized subjects were exposed 45 min in each of the cubicles. A model for the combined effect of operative temperature of room, moisture content of room air, temperature of supply air and moisture content of supply air was developed based on the experiments. Reduction of moisture content in the supply air by 1.6 g/kg had the same effect as lowering the operative temperature by 1 degree C. The solar-powered system for supplying dry air is a low-cost alternative to traditional air conditioning in hot and humid regions.

  14. Effects of boosting the supply temperature on pipe dimensions of low-energy district heating networks

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2015-01-01

    This paper presents a method for the dimensioning of the low-energy District Heating (DH) piping networks operating with a control philosophy of supplying heat in low-temperature such as 55 °C in supply and 25°C in return regularly while the supply temperature levels are being boosted in cold...... winter periods. The performance of the existing radiators that were formerly sized with over-dimensions was analyzed, its results being used as input data for the performance evaluation of the piping network of the low-energy DH system operating with the control philosophy in question. The optimization...

  15. Information system for the supply chain management

    OpenAIRE

    Delia Adriana Marincas

    2008-01-01

    Supply chain management SCM is the integration and management of supply chain organizations and activities through collaboration, effective business processes and high levels of information sharing. The supply chain concept has become a concern due to global competition and increasing customer demand for value. Thus, the information must be available in real time across the supply chain and this can not be achieved without an integrated software system for supply chain management. Supply chai...

  16. 地埋管地源热泵热水供应系统运行性能的影响因素%Influencing factors of operating performance of ground-source heat pump hot water supply systems

    Institute of Scientific and Technical Information of China (English)

    王成勇; 雷俊; 王雁生; 宋月贤

    2012-01-01

    建立了地埋管地源热泵热水供应系统实验平台,研究了环境温度、间歇/连续运行工况、管内循环液流速等对地埋管换热器换热能力的影响,并研究了地埋管换热器周围土壤温度场的变化.结果表明,地埋管地源热泵热水供应系统基本不受环境温度的影响;采用间歇运行,有利于提高地埋管换热器的换热能力;地埋管换热器平均单位井深换热量随管内循环液流速的增大而增大,但当流速增大到一定程度时,其增幅趋于平缓.%Establishes an experimental platform for ground-source heat pump system (GCHP) hot water supply system. Studies the influences of ambient temperature, intermittent or continuous operation mode and flow rate of circulating fluid on the heat exchange efficiency, and studies the variation of soil temperature field around ground heat exchangers. The results show that the GSHP hot water supply system is little influenced by the ambient temperature; intermittent operation mode is conducive to improving the heat exchange capacity of the ground heat exchanger; the heat flow of unit borehole depth of the ground heat exchanger increases along with the fluid flow rate until the fluid flow rate rises to a certain extent when the increasing trends became flat.

  17. Use of hydrogeothermal energy to support traditional heat supply systems; Nutzung der Energie von geothermalen Gewaessern zur Unterstuetzung der traditionellen Waermeversorgungssysteme

    Energy Technology Data Exchange (ETDEWEB)

    Kabat, M.; Nowak, W.; Sobanski, R. [Technische Univ., Szczecin (Poland)

    1997-12-01

    In the Szczecin Region, there are considerable resources of geothermal waters with temperatures from about 30 to 120 C. The authors present in their paper, on the example of selected urban centres, a possibility of utilising geothermal energy for modernisation of traditional heating systems. Among others, the idea of using geothermal energy in combination with conventional heat and power plants has been discussed and the geothermal heating system in Pyrzyce commissioned in February 1996 has been presented. (orig.) [Deutsch] In der Woiwodschaft-Szczecin sind betraechtliche Vorraete der geothermalen Gewaesser mit den Temperaturen von 30 bis ca. 120 C vorhanden. Im vorliegenden Referat stellen die Autoren am Beispiel einiger staedtischer Gebiete die Moeglichkeit, die geothermale Energie zur Modernisierung der traditionellen Waermeversorgungssysteme zu nutzen. Unter anderem wurde das Nutzungskonzept der geothermalen Waermequelle gekopplelt mit konventionellen Heizkraftwerken beschrieben und das im Februar 1996 in Betrieb genommene geothermale Waermeversorgungssysteme in Pyrzyce praesentiert. (orig.)

  18. Exergy performance of different space heating systems: A theoretical study

    DEFF Research Database (Denmark)

    Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

    2016-01-01

    Three space heating systems (floor heating with different floor covering resistances, radiator heating with different working temperatures, warm-air heating with and without heat recovery) were compared using a natural gas fired condensing boiler as the heat source. For the floor heating systems......, the effects of floor covering resistance on the whole system performance were studied using two heat sources; a natural gas fired condensing boiler and an air-source heat pump. The heating systems were also compared in terms of auxiliary exergy use for pumps and fans. The low temperature floor heating system...... performed better than other systems in terms of exergy demand. The use of boiler as a heat source for a low-exergy floor heating system creates a mismatch in the exergy supply and demand. Although an air-source heat pump could be a better heat source, this depends on the origin of the electricity supplied...

  19. Application of evaporative condensation air conditioning system of cooling combined heating and domestic hot water supply%供冷供暖供生活热水蒸发式冷凝空调系统的应用

    Institute of Scientific and Technical Information of China (English)

    谭海阳; 屈国伦; 黄伟; 江慧妍; 陈少玲

    2012-01-01

    Considering supplied domestic hot water temperature lower than the required 60 'C and lower system energy efficiency of the existed system, presents the new system as solution to the above situation. Performing the heat recovering according to cascad principle of energy use, recovers partial 1 latent heat and total sensible heat while the condensing temperature is not risen. Presents the working modes of heat charging, discharging and standby of heat recovering system. With an actual project, presents the detailed parameters of the unit and design calculation of the heat recovering system. Operation analysis of cooling period shows that the heat recovering quantity is always more than heat demand of domestic water, namely, the free domestic hot water can be obtained in whole cooling period.%针对目前供冷供暖供生活热水系统的热水温度达不到60℃,且系统能效较低的现状,提出了该空调系统作为解决方案,根据能源梯级利用原则,在不提高冷凝温度的同时回收了部分潜热及全部显热.介绍了热回收系统蓄热阶段、用热阶段和不用热阶段的工作模式.结合某工程实例,介绍了机组的详细参数以及热回收热水系统的设计计算,供冷期的运行分析结果表明,在不同负荷率工况下,热回收量均大于生活热水用热量,即在供冷期,可以免费提供生活热水.

  20. Integration of Space Heating and Hot Water Supply in Low Temperature District Heating

    DEFF Research Database (Denmark)

    Elmegaard, Brian; Ommen, Torben Schmidt; Markussen, Michael

    2014-01-01

    District heating makes it possible to provide heat for many consumers in an efficient manner. In particular, district heating based on combined heat and power production is highly efficient. One disadvantage of district heating is that there is a significant heat loss from the pipes to the surrou......District heating makes it possible to provide heat for many consumers in an efficient manner. In particular, district heating based on combined heat and power production is highly efficient. One disadvantage of district heating is that there is a significant heat loss from the pipes...... to the surrounding ground. In larger networks involving both transmission and distribution systems, the heat loss is most significant from the distribution network. An estimate is that about 80-90 % of the heat loss occurs in the distribution system. In addition, the heat loss is naturally highest from the forward...

  1. Physical and chemical parameter correlations with technical and technological characteristics of heating systems and the presence of Legionella spp. in the hot water supply.

    Science.gov (United States)

    Rakić, Anita; Štambuk-Giljanović, Nives

    2016-02-01

    The purpose of this study was to evaluate the prevalence of Legionella spp. and compare the quality of hot water between four facilities for accommodation located in Southern Croatia (the Split-Dalmatian County). The research included data collection on the technical and technological characteristics in the period from 2009 to 2012. The survey included a type of construction material for the distribution and internal networks, heating system water heater type, and water consumption. Changes in water quality were monitored by determination of the physical and chemical parameters (temperature, pH, free chlorine residual concentrations, iron, zinc, copper and manganese) in the samples, as well as the presence and concentration of bacteria Legionella spp. The temperature is an important factor for the development of biofilms, and it is in negative correlation with the appearance of Legionella spp. Positive correlations between the Fe and Zn concentrations and Legionella spp. were established, while the inhibitory effect of a higher Cu concentration on the Legionella spp. concentration was proven. Legionella spp. were identified in 38/126 (30.2%) of the water samples from the heating system with zinc-coated pipes, as well as in 78/299 (26.1%) of the samples from systems with plastic pipes. A similar number of Legionella spp. positive samples were established regardless of the type of the water heating system (central or independent). The study confirms the necessity of regular microbial contamination monitoring of the drinking water distribution systems (DWDSs).

  2. District heating supply for low energy areas. second edition; Fjernvarmeforsyning af lavenergiomraeder. 2 udgave

    Energy Technology Data Exchange (ETDEWEB)

    Kristjansson, H.; Buus, F. [Carl Bro as, Glostrup (Denmark); Boehm, B.; Vejen, N.K. [Danmarks Tekniske Univ., Kgs. Lyngby (Denmark); Rasmussen, J. [Star Pipe, Fredericia (Denmark); Paaske Christensen, K. [Nykoebing Falster Kommune, Nykoebing Falster (Denmark); Bidstrup, N. [Grundfos A/S, Broendby (Denmark)

    2004-08-01

    This report presents recommendations for design of district heating distribution systems in low energy buildings or in other areas with low heating density. For a joint heat supply of areas with low heat density distribution costs are high compared to heat sale. At the same time district heating flow pipes and pumps have developed significantly during the last decade. The project aims at identifying the optimal district heating distribution design for these conditions. The optimal design is dependent on heat price, price level and economic timeframe. Furthermore, savings are dependent of choice of frame of reference. Conditions can vary significantly from one area to another, but preconditions have been adapted to a reasonable level. (BA)

  3. Power supply system for KSTAR neutral beam injector

    Energy Technology Data Exchange (ETDEWEB)

    Cho, W., E-mail: franciscocho@nfri.re.kr; Bae, Y.S.; Han, W.S.; Jeong, J.H.; Kim, J.S.; Park, H.T.; Yang, H.L.; Oh, Y.K.; Kwak, J.G.

    2015-10-15

    Highlights: • The power supply system in KSTAR NBI consists of DC power supplies for ion source. • For operation NBI, DC High Voltage based on the low voltage transformer with chopper. • The surge absorber near the ion source limit the energy deposited to accelerator grid. - Abstract: The power supply system in KSTAR neutral beam injector consists of low voltage and high current DC power supplies for plasma generator of ion source and high voltage and high current DC power supply for accelerator grid system. The arc discharge is initiated by an arc power supply supplying the arc voltage between the chamber wall and 12 filaments which are heated by individual filament power supply. The negative output of arc power supply is common to each positive output of 12 filament power supplies. To interrupt the arc discharging for the fault condition of the arc current unbalance, DCCT current monitor is placed at the positive output cable of the filament power supply. The plasma grid (G1) power supply has the maximum capability of 120 kV/70 A which consists of low voltage regulator with IGBT-switched chopper array system for the voltage control in unit of 600 V and the high voltage rectified transformers to supply DC voltage of 20 kV, 30 kV, and 50 kV. The output voltage of the G1 power supply is also connected to the input of the voltage divider system which supplies the gradient voltage to the gradient grid (G2) in the range of 80–90% of G1 voltage by changing tap of winding resistors in unit of 1%. The charged G1 voltage is turned on and off by the high voltage switch (HVS) system consisting of MOSFET fast semiconductor switches which can immediately be opened less than 1 μs when the ion source grid breakdown occurs. The decelerating grid (G3) power supply is inverter system using capacitor-charge power supply to supply maximum −5 kV/5 A. The important component in power supply system is the surge absorber near the ion source to limit the arc energy deposited to

  4. Energy Supply System for Industrial Poultry Houses

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2016-04-01

    Full Text Available The gas engine driven carbon dioxide heat pump designed for providing the heat, cold and electricity for industrial poultry house is proposed. The scheme differs from the known by using recuperative heat exchanger installed between the exhaust air duct of poultry house and heat pump evaporator and the heat curtain installed on the air duct after the evaporator. The air coming into the poultry house after the regenerative heat exchanger is supplied to the heat pump gas cooler. The heat pump produces heat of the required parameters of the input air and water for watering of poultry, space heating, etc. Heat pump compressor is driven by gas engine (GPA, by natural gas or biogas. The part of the gas-piston engine heat is used for adjusting the optimal heat pump mode and for regeneration of the absorbent in an evaporative cooler. The proposed technical solution of the above scheme provides a higher COP of the heat pump. Installing of heat curtain does not require the use of non-freezing solution to prevent icing of the air outlet of heat pump evaporator. The latter allows producing, besides electric power and heat, still cold (with the use off the adsorption-refrigerating machine and provide drying air inlet evaporative cooler (if necessary.

  5. Visualisation for System Learning in Supply Chains

    Science.gov (United States)

    Lindskog, Magnus; Abrahamsson, Mats; Aronsson, Hakan

    2007-01-01

    Contemporary supply chains are vastly complex, and decisions made by actors have system-wide consequences that these might not be able to foresee. There are gaps between "best practice"-founded theory and actual practice in supply chains. To remedy this, we argue, the supply chain actors need to enhance systems knowledge. There is a need to…

  6. The potential to supply low temperature district heating to existing building area

    DEFF Research Database (Denmark)

    Li, Hongwei; Svendsen, Svend

    2013-01-01

    Low-temperature district heating (LTDH) has the advantages as reduced network heat loss, improved quality match between energy supply and energy demand, and increased utilization of low-grade waste heat and renewable energy. The LTDH represents the next generation district heating (DH) system....... The use of LTDH for low energy buildings was demonstrated through pilot projects carried out in Denmark. However, the majority of the buildings were built during the time when there had little requirement for building energy conservation. In order to implement the LTDH in a large scale, its feasibility...

  7. Heating systems for heating subsurface formations

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Scott Vinh (Houston, TX); Vinegar, Harold J. (Bellaire, TX)

    2011-04-26

    Methods and systems for heating a subsurface formation are described herein. A heating system for a subsurface formation includes a sealed conduit positioned in an opening in the formation and a heat source. The sealed conduit includes a heat transfer fluid. The heat source provides heat to a portion of the sealed conduit to change phase of the heat transfer fluid from a liquid to a vapor. The vapor in the sealed conduit rises in the sealed conduit, condenses to transfer heat to the formation and returns to the conduit portion as a liquid.

  8. Intensification of Convective Heat Transfer in Heating Device of Mobile Heating System with BH-Heat Generator

    Directory of Open Access Journals (Sweden)

    N. Nesenchuk

    2013-01-01

    Full Text Available Directions pertaining to intensification of convective heat transfer in a soft heating device have been experimentally investigated  in the paper and the most efficient one has been selected that is creation of artificial roughness on the device surface. The considered heating device for a heat supply system of a mobile object has been made of soft polymer material (polyvinyl chloride. Following  evaluation results of  heat exchange intensification a criteria equation has been obtained for calculation of external heat transfer with due account of heat transfer intensification.

  9. PREDICTIVE CONTROL SYSTEM SYNTHESIS OF DISTRICT HEATING SYSTEM

    Directory of Open Access Journals (Sweden)

    Dobrotin S.A.

    2011-08-01

    Full Text Available A combined system of building heating predictive control has been synthesized in the research. Following algorithms are described: adaptive algorithm of very short-term temperature forecast and algorithm of anticipatory control of heat supply to building heating taking into account different outside climate influence on elevations of a building.

  10. Application of SAW method for multiple-criteria comparative analysis of the reliability of heat supply organizations

    Science.gov (United States)

    Akhmetova, I. G.; Chichirova, N. D.

    2016-12-01

    Heat supply is the most energy-consuming sector of the economy. Approximately 30% of all used primary fuel-and-energy resources is spent on municipal heat-supply needs. One of the key indicators of activity of heat-supply organizations is the reliability of an energy facility. The reliability index of a heat supply organization is of interest to potential investors for assessing risks when investing in projects. The reliability indices established by the federal legislation are actually reduced to a single numerical factor, which depends on the number of heat-supply outages in connection with disturbances in operation of heat networks and the volume of their resource recovery in the calculation year. This factor is rather subjective and may change in a wide range during several years. A technique is proposed for evaluating the reliability of heat-supply organizations with the use of the simple additive weighting (SAW) method. The technique for integrated-index determination satisfies the following conditions: the reliability level of the evaluated heat-supply system is represented maximum fully and objectively; the information used for the reliability-index evaluation is easily available (is located on the Internet in accordance with demands of data-disclosure standards). For reliability estimation of heat-supply organizations, the following indicators were selected: the wear of equipment of thermal energy sources, the wear of heat networks, the number of outages of supply of thermal energy (heat carrier due to technological disturbances on heat networks per 1 km of heat networks), the number of outages of supply of thermal energy (heat carrier due to technologic disturbances on thermal energy sources per 1 Gcal/h of installed power), the share of expenditures in the cost of thermal energy aimed at recovery of the resource (renewal of fixed assets), coefficient of renewal of fixed assets, and a coefficient of fixed asset retirement. A versatile program is developed

  11. Induction Heating Systems

    Science.gov (United States)

    1991-01-01

    Induction heating technology, a magnetic non-deforming process, was developed by Langley researchers to join plastic and composite components in space. Under NASA license, Inductron Corporation uses the process to produce induction heating systems and equipment for numerous applications. The Torobonder, a portable system, comes with a number of interchangeable heads for aircraft repair. Other developments are the E Heating Head, the Toroid Joining Gun, and the Torobrazer. These products perform bonding applications more quickly, safely and efficiently than previous methods.

  12. Design of a low temperature district heating network with supply recirculation

    DEFF Research Database (Denmark)

    Li, Hongwei; Dalla Rosa, Alessandro; Svendsen, Svend

    2010-01-01

    The focus on continuing improving building energy efficiency and reducing building energy consumption brings the key impetus for the development of the new generation district heating (DH) system. In the new generation DH network, the supply and return temperature are designed low in order...

  13. A new bipolar Qtrim power supply system

    Energy Technology Data Exchange (ETDEWEB)

    Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drozd, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Nolan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Orsatti, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Heppener, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Di Lieto, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schultheiss, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Zapasek, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    This year marks the 15th run of RHIC (Relativistic Heavy Ion Collider) operations. The reliability of superconducting magnet power supplies is one of the essential factors in the entire accelerator complex. Besides maintaining existing power supplies and their associated equipment, newly designed systems are also required based on the physicist’s latest requirements. A bipolar power supply was required for this year’s main quadruple trim power supply. This paper will explain the design, prototype, testing, installation and operation of this recently installed power supply system.

  14. A Danish Heat Atlas for Supply Strategies and Demand Side Management

    DEFF Research Database (Denmark)

    Möller, Bernd

    heat demand and possible savings. The location of each building relative to heat supply technologies is mapped and used for the assessment of supply strategies by potentials, costs and environmental impact. Both elements can furthermore be used to balance investments in supply with investments......The expansion of district heating, the assessment of the impact of heat supply strategies, as well as the analysis of significant heat demand savings require sound decision support at high detail. Data is needed to continuously quantify potentials and costs of measures in the end-use and supply...

  15. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 1: Cost of feedstock supply logistics

    Energy Technology Data Exchange (ETDEWEB)

    Sokhansanj, S.; Turhollow, A.F. [Environmental Sciences Division, Oak Ridge National Laboratory, PO Box 2008, Oak Ridge, TN 37831 (United States); Mani, S. [Biological and Agricultural Engineering, Driftmier Engineering Center, University of Georgia, Athens, GA 30602 (United States); Tagore, S. [Office of Biomass Program, US Department of Energy, Washington, DC 20585 (United States)

    2010-01-15

    Supply of corn stover to produce heat and power for a typical 170 dam{sup 3} dry mill ethanol plant is proposed. The corn ethanol plant requires 5.6 MW of electricity and 52.3 MW of process heat, which creates the annual stover demand of as much as 140 Gg. The corn stover supply system consists of collection, pre-processing, transportation and on-site fuel storage and preparation to produce heat and power for the ethanol plant. Economics of the entire supply system was conducted using the Integrated Biomass Supply Analysis and Logistics (IBSAL) simulation model. Corn stover was delivered in three formats (square bales, dry chops and pellets) to the combined heat and power plant. Delivered cost of biomass ready to be burned was calculated at 73 Mg{sup -1} for bales, 86 Mg{sup -1} for pellets and 84 Mg{sup -1} for field chopped biomass. Among the three formats of stover supply systems, delivered cost of pelleted biomass was the highest due to high pelleting cost. Bulk transport of biomass in the form of chops and pellets can provide a promising future biomass supply logistic system in the US, if the costs of pelleting and transport are minimized. (author)

  16. Techno-economic analysis of using corn stover to supply heat and power to a corn ethanol plant - Part 1: Cost of feedstock supply logistics

    Energy Technology Data Exchange (ETDEWEB)

    Sokhansanj, Shahabaddine [ORNL; Mani, Sudhagar [University of Georgia; Togore, Sam [U.S. Department of Energy; Turhollow Jr, Anthony F [ORNL

    2010-01-01

    Supply of corn stover to produce heat and power for a typical 170 dam3 dry mill ethanol plant is proposed. The corn ethanol plant requires 5.6 MW of electricity and 52.3 MW of process heat, which creates the annual stover demand of as much as 140 Gg. The corn stover supply system consists of collection, preprocessing, transportation and on-site fuel storage and preparation to produce heat and power for the ethanol plant. Economics of the entire supply system was conducted using the Integrated Biomass Supply Analysis and Logistics (IBSAL) simulation model. Corn stover was delivered in three formats (square bales, dry chops and pellets) to the combined heat and power plant. Delivered cost of biomass ready to be burned was calculated at 73 $ Mg-1 for bales, 86 $ Mg-1 for pellets and 84 $ Mg-1 for field chopped biomass. Among the three formats of stover supply systems, delivered cost of pelleted biomass was the highest due to high pelleting cost. Bulk transport of biomass in the form of chops and pellets can provide a promising future biomass supply logistic system in the US, if the costs of pelleting and transport are minimized.

  17. Heat Pipe Systems

    Science.gov (United States)

    1988-01-01

    Solar Fundamentals, Inc.'s hot water system employs space-derived heat pipe technology. It is used by a meat packing plant to heat water for cleaning processing machinery. Unit is complete system with water heater, hot water storage, electrical controls and auxiliary components. Other than fans and a circulating pump, there are no moving parts. System's unique design eliminates problems of balancing, leaking, corroding, and freezing.

  18. Multilevel Flow Modeling of Domestic Heating Systems

    DEFF Research Database (Denmark)

    Hu, Junjie; Lind, Morten; You, Shi

    2012-01-01

    of complementing this reasoning methodology. Domestic heating systems, as the main resource to meet the thermal requirements of end-users, have different implementations in Europe in order to achieve various degrees of controllability and heating efficiencies. As all the heating systems serve the same basic needs...... i.e. supplying and transferring thermal energy, it is off interest to use MFM to investigate similarities and differences between different implementations. In this paper, three typical domestic European heating systems, which differ from each other in the number of temperature sensors and auxiliary...

  19. Heat rejection system

    Science.gov (United States)

    Smith, Gregory C.; Tokarz, Richard D.; Parry, Jr., Harvey L.; Braun, Daniel J.

    1980-01-01

    A cooling system for rejecting waste heat consists of a cooling tower incorporating a plurality of coolant tubes provided with cooling fins and each having a plurality of cooling channels therein, means for directing a heat exchange fluid from the power plant through less than the total number of cooling channels to cool the heat exchange fluid under normal ambient temperature conditions, means for directing water through the remaining cooling channels whenever the ambient temperature rises above the temperature at which dry cooling of the heat exchange fluid is sufficient and means for cooling the water.

  20. Progress of Power Supply System in 2003

    Institute of Scientific and Technical Information of China (English)

    GaoDaqing; ZhouZhongzu; WuRong; ChenYouxin

    2003-01-01

    CSR power supply system made a great progress in 2003. All power supplies for CSRm E-cooler have been accepted and put into operation since Feb. 2003. And we are preparing to test power supplies of CSRe cooler 31 sets pulsed convertor for CSRm quadruple magnet arrived in IMP. But their output current must be increased from 590 A to 700 A, because of higher beam energy. 12 of them can fit the new request, but the others have to be redesigned and reproduced. The dipole power supply was assembled in plant and by using the power supply was some experiment made. The first test results was excited. Now this device has been installed in IMP and connected with the dipole magnet. We invited a public bidding for RIBLL2 and CSRe power supplies last September. Two companies provided 128 power supplies, which will be delivered to IMP before June 2004.

  1. THE CONCEPT OF UNINTERRUPTED POWER SUPPLY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2016-05-01

    Full Text Available We have revealed the main reasons for interruptions in power supply to consumers of electricity. To improve the reliability and the efficiency of power supply for responsible consumers, we have proposed to develop energy efficient combined energy-saving systems for uninterrupted power supply with use of renewable energy sources. The article lists major principles of the development of such systems; it shows the necessity of constructing a generalized schema that contains the possible types and the sources of electric power converters. It also reveals the modern requirements to systems of uninterrupted energy supply. To improve the operational and technical characteristics of the uninterruptible power supply, it has been proposed to use a new circuitry that includes a contactless power generators, the direct frequency converters used to stabilize the voltage and frequency of the current generators of wind turbines, static converters made with the use of single-phase transformers with rotating magnetic field, universal static converters that can operate in the regimes of known types of converters. The article presents features of the modular construction of systems of uninterrupted energy supply and optimization of their structural decisions on key performance criteria. It shows the algorithm of synthesis of structural designs of combined systems of uninterrupted power supply. An important step for further research with the aim of improving operational and technical characteristics of the combination of uninterrupted power supply systems is the mathematical modeling of physical processes in power circuits of the system in both normal and emergency modes of operation

  2. Active Power Flow Optimization of Industrial Power Supply with Regard to the Transmission Line Conductor Heating

    Directory of Open Access Journals (Sweden)

    Leyzgold D.Yu.

    2015-04-01

    Full Text Available This article studies the problem of the transmission line conductor heating effect on the active power flows optimization in the local segment of industrial power supply. The purpose is to determine the optimal generation rating of the distributed power sources, in which the power flow values will correspond to the minimum active power losses in the power supply. The timeliness is the need to define the most appropriate rated power values of distributed sources which will be connected to current industrial power supply. Basing on the model of active power flow optimization, authors formulate the description of the nonlinear transportation problem considering the active power losses depending on the transmission line conductor heating. Authors proposed a new approach to the heating model parameters definition based on allowable current loads and nominal parameters of conductors as part of the optimization problem. Analysis of study results showed that, despite the relatively small active power losses reduction to the tune 0,45% due to accounting of the conductors heating effect for the present configuration of power supply, there are significant fluctuations in the required generation rating in nodes of the network to 9,32% within seasonal changes in the outer air temperature. This fact should be taken into account when selecting the optimum power of distributed generation systems, as exemplified by an arbitrary network configuration.

  3. Identifying the optimal supply temperature in district heating networks - A modelling approach

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2014-01-01

    of this study is to develop a model for thermo-hydraulic calculation of low temperature DH system. The modelling is performed with emphasis on transient heat transfer in pipe networks. The pseudo-dynamic approach is adopted to model the District Heating Network [DHN] behaviour which estimates the temperature...... dynamically while the flow and pressure are calculated on the basis of steady state conditions. The implicit finite element method is applied to simulate the transient temperature behaviour in the network. Pipe network heat losses, pressure drop in the network and return temperature to the plant...... are calculated in the developed model. The model will serve eventually as a basis to find out the optimal supply temperature in an existing DHN in later work. The modelling results are used as decision support for existing DHN; proposing possible modifications to operate at optimal supply temperature....

  4. Performance of a Solar Heating System with Photovoltaic Thermal Hybrid Collectors and Heat Pump

    DEFF Research Database (Denmark)

    Dannemand, Mark; Furbo, Simon; Perers, Bengt

    2017-01-01

    . When the solar collectors are unable to supply the heat demand an auxiliary heat source is used. Heat pumps can generate this heat. Liquid/water heat pumps have better performance than air/water heat pumps in cold climates but requires installation of a tubing system for the cold side of the heat pump....... The tubes are typically placed in the ground, requires a significant land area and increase the installation cost. A new system design of a solar heating system with two storage tanks and a liquid/water heat pump is presented. The system consists of PVT collectors that generate both heat and electricity....... Heat from the collectors is transferred to a domestic hot water storage tank or to a cold storage tank, which is used as the source for the heat pump. When the heat pump charges the warm storage tank, heat is extracted from the cold storage tank, which then can be reheated by the PVT collectors...

  5. Application of Predictive Control in District Heating Systems

    DEFF Research Database (Denmark)

    Palsson, Olafur Petur; Madsen, Henrik; Søgaard, Henning Tangen

    1993-01-01

    In district heating systems, and in particular if the heat production cakes place at a combined heat and power (CHP) plant, a reasonable control strategy is to keep the supply temperature from the district heating plant as low as possible. However, the control is subject to some restrictions....... A district heating system is an example of a non-stationary system, and the model parameters have to be time varying. Hence, the classical predictive control theory has to be modified. Simulation experiments are performed in order to study the performance of modified predictive controllers. The systems ape......, for example, that the total heat requirement for all consumers is supplied at any time and each individual consumer is guaranteed some minimum supply temperature at any time. A lower supply temperature implies lower heat loss from the transport and the distribution network, and lower production costs...

  6. Performance of Space Heating in a Modern Energy System

    DEFF Research Database (Denmark)

    Elmegaard, Brian

    2011-01-01

    In the paper we study the performance of a number of heat supply technologies. The background of the study is the changes in the Danish energy systems over the last three decades which have caused integration of large shares of combined heat and power (CHP), renewable fuels and wind power....... These changes mean that there is a significant integration of electricity and heat supply in the system and that several technologies may be beneficial. In particular, heat pumps are under consideration and are often considered to be renewable energy. We study how to distribute fuel and emissions to the heat...... supply. We find that heat supply is low-efficient seen from an exergy viewpoint, between 1% and 26% utilization. As exergy is a quantification of primary energy, we conclude that far better utilization of primary energy is possible. We also find that combined heat and power and domestic heat pumps...

  7. Active space heating and hot water supply with solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Karaki, S.; Loef, G. O.G.

    1981-04-01

    Technical and economic assessments are given of solar water heaters, both circulating, and of air-based and liquid-based solar space heating systems. Both new and retrofit systems are considered. The technical status of flat-plate and evacuated tube collectors and of thermal storage is also covered. Non-technical factors are also briefly discussed, including the participants in the use of solar heat, incentives and deterrents. Policy implications are considered as regards acceleration of solar use, goals for solar use, means for achieving goals, and interaction of governments, suppliers, and users. Government actions are recommended. (LEW)

  8. Understanding Supply Networks from Complex Adaptive Systems

    Directory of Open Access Journals (Sweden)

    Jamur Johnas Marchi

    2014-10-01

    Full Text Available This theoretical paper is based on complex adaptive systems (CAS that integrate dynamic and holistic elements, aiming to discuss supply networks as complex systems and their dynamic and co-evolutionary processes. The CAS approach can give clues to understand the dynamic nature and co-evolution of supply networks because it consists of an approach that incorporates systems and complexity. This paper’s overall contribution is to reinforce the theoretical discussion of studies that have addressed supply chain issues, such as CAS.

  9. Heating Systems Specialist.

    Science.gov (United States)

    Air Force Training Command, Sheppard AFB, TX.

    This instructional package is intended for use in training Air Force personnel enrolled in a program for apprentice heating systems specialists. Training includes instruction in fundamentals and pipefitting; basic electricity; controls, troubleshooting, and oil burners; solid and gas fuel burners and warm air distribution systems; hot water…

  10. Solar-heating system

    Science.gov (United States)

    1979-01-01

    Report describes solar modular domestic-hot-water and space-heating system intended for use in small single family dwelling where roof-mounted collectors are not feasible. Contents include design, performance, and hardware specifications for assembly, installation, operation, and maintenance of system.

  11. Indoor temperatures for calculating room heat loss and heating capacity of radiant heating systems combined with mechanical ventilation systems

    DEFF Research Database (Denmark)

    Wu, Xiaozhou; Olesen, Bjarne W.; Fang, Lei;

    2016-01-01

    system were determined according to the principle of heat transfer. A model to predict indoor temperatures in the room was proposed, and it was determined that the predicted indoor temperatures agreed well with the measured data. Qualitative analyses of the effects of heated surface temperature and air...... change rates on the indoor temperatures were performed using the proposed model. When heated surface temperatures and air change rates were from 21.0 to 29.0 degrees C and from 0.5 to 4.0 h-1, the indoor temperatures for calculating the transmission heat loss and ventilation heat loss were between 20.......8% for calculating the transmission heat loss and ventilation heat loss, respectively, and between 16.0% and 17.4% for calculating the heating capacity of the hybrid system. Due to large relative calculation errors, it is necessary to consider the effect of heated surface and cool supply air on indoor temperatures...

  12. DESIGN AND PERFORMANCE OF A SOLAR ABSORPTION AIR-CONDITIONING AND HEAT-SUPPLY SYSTEM%太阳能吸收式空调及供热系统的设计和性能

    Institute of Scientific and Technical Information of China (English)

    何梓年; 朱宁; 刘芳; 郭淑玲

    2001-01-01

    A solar absorption air-conditioning and heat-suppl ycomprehensive system has been constructed in Rushan,Shandong Province.The system consists of heat-pipe evacuated tubular collectors,lithium-bromide absorption c hiller,hot water storage tanks,chilled water storage tank,domestic water storage tank,circulating pumps,cooling tower,fan-coil units,auxiliary oil-burned boil er and control system.The system has a multifunction of space cooling in summer,sp ace heating in winter and domestic water heating in other seasons,with a total c ollector aperture area of 540m2,cooling and heating capacity of 100kW,air-con d itioning construction area of 1000m2 and domestic hot water supply of 32m3 p er day.Design characteristics and measuring performance of the system were prese nted.%一套太阳能吸收式空调及供热综合系统已在山东省乳山市建成。该系统由热管式真空管集热器、溴化锂吸收式制冷机、储水箱、循环泵、冷却塔、空调箱、辅助燃油锅炉和自动控制系统等几部分组成,具有夏季制冷、冬季供热和全年提供生活用热水等功能。太阳能集热器总采光面积540m2,制冷、供热功率100kW,空调、采暖建筑面积1000m2,供生活用热水量32m3/d。文中着重介绍了系统的设计特点和测试性能。

  13. NETWORK MODEL AND ALGORITHM FOR SOLVING PROBLEM OF OPTIMUM THERMAL LOAD DISTRIBUTION AMONG HEAT-SOURCES OF ENTERPRISE HEATING SYSTEM

    Directory of Open Access Journals (Sweden)

    V. A. Sednin

    2010-01-01

    Full Text Available The paper  presents an algorithm for optimization of thermal load distribution among heat-sources in the system of centralized heat supply. The algorithm can be used while elaborating plans for development of heat supply systems in cities and settlements.

  14. MULTIFUNCTIONAL SOLAR SYSTEMS FOR HEATING AND COOLING

    Directory of Open Access Journals (Sweden)

    Doroshenko A.V.

    2010-12-01

    Full Text Available The basic circuits of multifunctional solar systems of air drainage, heating (hot water supply and heating, cooling and air conditioning are developed on the basis of open absorption cycle with a direct absorbent regeneration. Basic decisions for new generation of gas-liquid solar collectors are developed. Heat-mass-transfer apparatus included in evaporative cooling system, are based on film interaction of flows of gas and liquid and in them, for the creation of nozzle, multi-channel structures from polymeric materials and porous ceramics are used. Preliminary analysis of multifunctional systems possibilities is implemented.

  15. Heat supply to low energy dwellings in district heating areas. Analyses of CO{sub 2} emissions and electricity supply security; Varmeforsyning til lavenergiboliger i omraader med fjernvarmekonsesjon. Analyser av CO{sub 2}-utslipp og forsyningssikkerhet for elektrisitet

    Energy Technology Data Exchange (ETDEWEB)

    Thyholt, Marit

    2006-07-01

    Building low energy dwellings in large development projects is a new situation in Norway. The municipalities have to a little extent analyzed the consequences of this new housing standard with respect to the energy supply to such areas, and how this standard may change the plans for new or extended district heat production. In the provision about the mandatory connection to district heating plants, and the appendant provision related to a heating system that can utilize district heat, the district heat supply and the heat demand are not seen in connection. The objective of this dissertation is to provide the municipalities with a basis for decision making in the processing of applications concerning dispensation from the mandatory connection or the heating system requirement for dwellings with low heat demand. This basis for decision making is based on the national aim of reducing carbon dioxide (CO{sub 2}) emissions and of improving the electricity supply security. This summary provides an abstract from the discussion of the legislation as an incentive or barrier for building low energy dwellings. An abstract from a survey among construction firms concerning the motivation for building low energy dwellings is also included. In addition, the summary provides a comprehensive abstract of the results from the CO{sub 2} emission calculations, and the basis for these calculations. Introductorily a brief background of the national focus on energy savings and increased use of hydronic heating, including district heat, is given.

  16. Coal slurry fuel supply and purge system

    Science.gov (United States)

    McDowell, Robert E.; Basic, Steven L.; Smith, Russel M.

    1994-01-01

    A coal slurry fuel supply and purge system for a locomotive engines is disclosed which includes a slurry recirculation path, a stand-by path for circulating slurry during idle or states of the engine when slurry fuel in not required by the engine, and an engine header fluid path connected to the stand-by path, for supplying and purging slurry fuel to and from fuel injectors. A controller controls the actuation of valves to facilitate supply and purge of slurry to and from the fuel injectors. A method for supplying and purging coal slurry in a compression ignition engine is disclosed which includes controlling fluid flow devices and valves in a plurality of fluid paths to facilitate continuous slurry recirculation and supply and purge of or slurry based on the operating state of the engine.

  17. Mobile central heating plant ensures the supply during the power-plant modernization. Planning-safe reconstruction; Mobile Heizzentrale sichert Versorgung waehrend Kraftwerksmodernisierung. Planungssicherer Umbau

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard, Petra [Mobiheat GmbH, Friedberg (Germany). Presse- und Oeffentlichkeitsarbeit

    2012-09-15

    During the comprehensive energetic retrofitting of district heating plants in the spa resort of Badenweiler (Federal Republic of Germany) a mobile 2-MW heating plant from Mobilheat (Ebersberg, Federal Republic of Germany) was used for the heat supply. Thus, the installation of environmental friendly energy supply based on cogeneration plants could be implemented with planning security. This particularly was important because, among other things, the traditional spa resort, the Kurhaus as well as hotels and private customers depend on the heat supply system. These buildings have be supplied with thermal water also in the summer.

  18. Solar-assisted heat supply in private homes. Solar unterstuetzte Waermeversorgung fuer private Haushalte

    Energy Technology Data Exchange (ETDEWEB)

    Hahne, E.; Fisch, N.

    1992-01-01

    Compared to decentralized systems, central heating in new residential areas proves to be rather more cost-effective and not more expensive. A volar support system will increase the price of heat but will still be cheaper than conventional single-application supply. In terms of a sparing use of raw materials and of CO[sub 2] emission reduction, the use of solar energy for heating and hot water is well worth thinking about although the resulting costs will be higher by a factor of 2 to 2.5 than the current cost of conventional energies. The government and local authorities should take a pioneering role in the propagation of solar-assisted systems today. (orig.)

  19. Domestic Heating and Cooling and Hot Water Supply System Based on Heat Pumps and Solar Energy%基于热泵和太阳能的住宅供暖供冷供生活热水三联供系统研究

    Institute of Scientific and Technical Information of China (English)

    魏海翔; 梁镇杰; 梁海珍; 刘翠华

    2014-01-01

    Residential heating and cooling water supply system for combined based on heat pumps and solar is a line with the social sustainable development, energy saving and environmental protection technical measures, it is a major breakthrough in air heat pump and solar energy industries. The system DC inverter air heat pump as the core,combined with solar energy,electricity and other energy to residential heating, cooling and domestic hot water provided, focus on solving the DC inverter air heat pump to residential and efficient heating, cooling, hot for life water, and solar and other alternative energy linkage, for residential heating cooling and domestic hot water systems integration and technology and other key technology issues.%基于热泵和太阳能的住宅供暖供冷供生活热水三联供系统是一项符合社会可持续发展的,节能环保的技术措施。该系统以直流变频空气能热泵为核心,结合太阳能、电能及其他能源,向住宅供暖、供冷及提供生活热水,着重解决了直流变频空气能热泵向住宅高效供暖、供冷、供生活热水,和太阳能及其他备用能源的联动,面向住宅供暖冷及生活热水的系统集成关键技术及工艺等问题。

  20. Design of ITER NBI power supply system

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Kazuhiro; Ohara, Yoshihiro; Okumura, Yoshikazu [Japan Atomic Energy Research Inst., Naka, Ibaraki (Japan). Naka Fusion Research Establishment; Higa, Osamu; Kawashima, Syuichi; Ono, Youichi; Tanaka, Masanobu; Yasutomi, Sei

    1997-07-01

    Power supply system for the ITER neutral beam injector (NBI) whose total injection power is 1 MeV, 50 MW from three modules, has been designed. The power supply system consists of a source power supply for negative ion production/extraction and a DC 1 MV, 45 A power supply for negative ion acceleration. An inverter controlled multi-transformer/rectifier system has been adopted to the acceleration power supply. An inverter frequency of 150 Hz was selected to satisfy required specifications which are rise time of <100 ms, voltage ripple of <10% peak to peak and cut off speed of <200{mu}s. It was confirmed that the rise time, the ripple and the cut off speed is about 50 ms, 7% and <200{mu}s respectively by computation. It was also confirmed that a surge current and an energy input to the ion source at the breakdown can be suppressed lower than 3 kA and 10 J, which are considered to be lower than allowable values. A 1 MV transmission line has been designed from a view point of electric field on the inner conductors and grounded conductor. The results from the design study indicate that all the required specification to the power supply system can be satisfied and that R and D on the transmission line is one of the most important subjects. (author)

  1. Geothermal district heating systems

    Science.gov (United States)

    Budney, G. S.; Childs, F.

    1982-06-01

    Ten district heating demonstration projects and their present status are described. The projects are Klamath County YMCA, Susanville District Heating, Klamath Falls District Heating, Reno Salem Plaza Condominium, El Centro Community Center Heating/Cooling, Haakon School and Business District Heating, St. Mary's Hospital, Diamond Ring Ranch, Pagosa Springs District Heating, and Boise District Heating.

  2. Potential evaluation of cold heat and hot heat supply by solar heat; Taiyonetsu ni yoru reinetsu onnetsu no kyokyu potential hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Akizawa, A.; Ishida, K.; Kashiwagi, T. [Tokyo Univ. of Agriculture and Technology, Tokyo (Japan)

    1997-01-30

    When the recovered solar heat is supplied to demands such as heating, cooling by absorption refrigerator and hot water supply, the maximum available heating value was determined using a model in which solar heat collector was installed in the residence, to investigate the possibility of alternative demand. In this study, the supply temperatures were 80 {degree}C for cooling, 50 {degree}C for heating, and 50 {degree}C for hot water supply, where a flat plate type heat collector was employed. It was assumed that the heat storage can be conducted for 24 hours. Results obtained are as follows. For detached houses, most of the monthly demand can be supplied due to the actual predominant fine days in each month. For the cold and intermediate periods, it was supposed that monthly demand can be supplied by using excess heating value of fine days in the case of sufficient capacity of heat storage tank. For the model with heat insulating structure, demands except hot water supply can be supplied from solar energy. It was found that the heat insulation greatly contributes to the energy saving. 6 refs., 5 figs., 2 tabs.

  3. Potential evaluation of cold heat and hot heat supply by solar heat; Taiyonetsu ni yoru reinetsu onnetsu no kyokyu potential hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Akizawa, A.; Ishida, K.; Kashiwagi, T. [Tokyo Univ. of Agriculture and Technology, Tokyo (Japan)

    1997-01-30

    When the recovered solar heat is supplied to demands such as heating, cooling by absorption refrigerator and hot water supply, the maximum available heating value was determined using a model in which solar heat collector was installed in the residence, to investigate the possibility of alternative demand. In this study, the supply temperatures were 80 {degree}C for cooling, 50 {degree}C for heating, and 50 {degree}C for hot water supply, where a flat plate type heat collector was employed. It was assumed that the heat storage can be conducted for 24 hours. Results obtained are as follows. For detached houses, most of the monthly demand can be supplied due to the actual predominant fine days in each month. For the cold and intermediate periods, it was supposed that monthly demand can be supplied by using excess heating value of fine days in the case of sufficient capacity of heat storage tank. For the model with heat insulating structure, demands except hot water supply can be supplied from solar energy. It was found that the heat insulation greatly contributes to the energy saving. 6 refs., 5 figs., 2 tabs.

  4. Towards a Future of District Heating Systems with Low-Temperature Operation together with Non-Fossil Fuel Heat Sources

    DEFF Research Database (Denmark)

    Tol, Hakan; Dinçer, Ibrahim; Svendsen, Svend

    2012-01-01

    This study focused on investigation of non-fossil fuel heat sources to be supplied to low-energy district heating systems operating in low temperature such as 55 C and 25 C in terms of, respectively, supply and return. Vast variety of heat sources classed in categories such as fossil fuel, renewa...

  5. Winter performance of a domestic solar-heating system--Duffield, Virginia

    Science.gov (United States)

    1981-01-01

    Sunlight supplies 39 percent of heat load, saving 9 barrels of fuel oil in one heating season. Report describes system installation in two-story, single-family residence. Energy is collected with roof-mounted air flat-plate collectors, stored in rock bin, and transferred to water preheat tank whenever system is storing energy; heat pump supplies heat to house.

  6. Improving the performance of district heating systems by utilization of local heat boosters

    DEFF Research Database (Denmark)

    Falcone, A.; Dominkovic, D. F.; Pedersen, A. S.

    LTDH grid as they will have the strategical role of connecting the heating system with the electrical energy coming from the intermittent and fluctuating renewable energy sources such as wind and solar power. In this paper a case study of district heating system is presented and analysed. The goal......District Heating (DH) plays an important role into the Danish energy green transition towards the future sustainable energy systems. The new, 4 th generation district heating network, the so called Low Temperature District Heating (LTDH), tends to lower the supply temperature of the heat down to 40......-50°C with return temperatures of 20-30 °C. This kind of heating system has many advantages and among all of them, it allows utilization of the heat coming from low exergy heat sources, as well as to decrease the grid heat losses. Electrical energy driven heat sources are also integrated into the future...

  7. Abandoned coal mine tunnels: Future heating/power Supply centers

    Institute of Scientific and Technical Information of China (English)

    Luo Pingjia; Chen Ning

    2011-01-01

    We have studied three plans for re-use of the abandoned mine roadway tunnels as an energy center.These are the thermostat plan,the thermal accumulator plan,and the CAES plan.Calculations show that the thermostat plan can provide over 15,000 m2 of building air-conditioning/heating load for each kilometer of roadway,but electric power is needed to run the system.Numerical research proved that the accumulation of hot water in the roadway for seasonal heating purposes (a temperature swing from 90 to 54 ℃) is a viable possibility.The CAES plan proposes using the discarded coal mine tunnel as a peaking power station with an energy storage density over 7000 kJ/m3.It can be concluded that presently abandoned coal mines could be reformed into future energy centers for a city.

  8. Beneficial use of waste heat in municipal water supply. Technical report TR-79-3

    Energy Technology Data Exchange (ETDEWEB)

    Porter, R.W.

    1979-08-01

    The relatively low temperature of thermal discharges from steam-electric power plants makes waste-heat utilization difficult without modification of the power cycle and attendant reduction in electrical energy generated. In situ beneficial use of waste heat by direct once-through condenser discharge into a municipal water supply is discussed. Computations are presented regarding the matching of flow rates, heat losses in distribution and energy savings. A number of benefits and penalties are also assessed qualitatively including legal and operational aspects and reliability. Especially attractive are improvements in electrical generating efficiency, and savings in water-heater energy. Secondary advantages include alleviation of pipe freeze up in winter and improved efficiency of slightly heated waste-water treatment. Penalties include additional pumping power for distribution in the water supply due to increased back pressure on the steam turbines which employ condensers cooled by the water they pump. Additional chlorine is also required to maintain a residual concentration in the distribution system. There may also be difficulties with public acceptance of water preheated by up to about 24/sup 0/F, especially in summer. The water supply of greater Chicago and 4880 MW(e) of colocated fossil-fired load-following generating capacity were analyzed as a hypothetical test case. It was concluded that the net annual energy savings is 23 x 10/sup 12/B, equivalent to 4 million bbl of oil, with a net savings in cost of $12./capita for the population of 4.66 m. While not developed for energy conservation purposes, three actual systems with operating experience are summarized. In order to determine feasibility of application, site-specific systems analysis is required.

  9. VENTILATION SYSTEM WITH GROUND HEAT EXCHANGER

    Directory of Open Access Journals (Sweden)

    Vyacheslav Pisarev

    2016-11-01

    Full Text Available Ventilation systems consume more and more energy because of the often complex treatment of the air supplied to closed spaces. Looking for sources of energy allow for significant savings costs, which often translate into renewable energy sources. One of the more popular solutions is to use energy from the ground by various methods. Known and relatively common solutions are based on ground heat exchanger and ground collector cooperating with a heat pump. The paper presents the possibility of cooperation ventilation system with ground air heat exchanger and heat pump both in summer and winter period. A number solutions of this type of system, supported by calculation examples and moist air transformation in the Moliere chart have been presented. Support ventilation system with renewable energy sources allows significant savings in operating as shown in the article.

  10. MATHEMATICAL MODELING OF THERMOPHYSICAL PARAMETERS OF VORTEX HEAT EXCHANGER OF HEATING SYSTEMS OF GAS DISTRIBUTION POINTS PREMISES

    Directory of Open Access Journals (Sweden)

    V. A. Lapin

    2009-09-01

    Full Text Available The mathematical model of heat transfer in vortex heat exchanger using natural gas energy which is released under decompression in gas-main pipe-lines for consumers of gas supply systems (dwellings, public and industrial buildings.

  11. The role of enterprise systems in supply chain networks: a taxonomy of supply chain strategies

    DEFF Research Database (Denmark)

    Møller, Charles

    2006-01-01

    This paper proposes a taxonomy for supply chain integration strategies. The taxonomy is based on the contingencies of supply chain network coupling and the Extended Enterprise Systems (EES) architecture in the supply chain. The purpose of this model is to map the portfolio of relations...... in the supply chain and to choose the right supply chain strategy. The work is based on a comprehensive study of the Supply Chain Management (SCM) and Enterprise Resource Planning (ERP) literature and the study suggests that there is an emerging new research potential for Enterprise Systems (ES) in the supply...

  12. The role of enterprise systems in supply chain networks: a taxonomy of supply chain strategies

    DEFF Research Database (Denmark)

    Møller, Charles

    2006-01-01

    in the supply chain and to choose the right supply chain strategy. The work is based on a comprehensive study of the Supply Chain Management (SCM) and Enterprise Resource Planning (ERP) literature and the study suggests that there is an emerging new research potential for Enterprise Systems (ES) in the supply......This paper proposes a taxonomy for supply chain integration strategies. The taxonomy is based on the contingencies of supply chain network coupling and the Extended Enterprise Systems (EES) architecture in the supply chain. The purpose of this model is to map the portfolio of relations...

  13. ARN Supply Chain Management System for OCIE

    Science.gov (United States)

    2006-12-30

    Module (IRM), Clothing Initial Issue Point ( CIIP ); Supply Chain Management; Virtual Item Manager/Wholesale Local; Quality Logistics Management...DLA successfully assumed retail inventory at five Army Clothing Initial Issue Points ( CIIPs ), two United Stated Marine Corps Recruit Depots (MCRDs...system provides a “local” capability to manage wholesale inventory assets located at the CIIP including receipt and inventory adjustment processing

  14. Energy consumption in the food supply system

    DEFF Research Database (Denmark)

    Kamp, Andreas; Østergård, Hanne; Hauggaard-Nielsen, Henrik

    2016-01-01

    Historically, productivity gains have been possible by the application of energy intensive technologies. In the future, new technologies and practices based on energy from renewable resources are central for the development of our food supply system and they will contribute in two different ways....... As the energy sector increasingly bases energy supply on renewable sources, the energy requirements of the food sector will automatically substitute renewable energy for non-renewable energy in all stages of food supply. In principle, the food sector does not need to change if renewable energy is sufficient...... and available as the energy carriers that we are used to today. We may think of this as passive adaptation. A passive adaptation strategy may support a development towards the image ‘high input – high output’. The food sector, however, may also actively adapt to a future without fossil fuels and change...

  15. RESEARCH OF EFFICIENCY OF WALL-MOUNTED BOILERS WITH SEALED CHAMBERS USED AS FLAT HEATING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Khavanov Pavel Aleksandrovich

    2012-12-01

    the heating system analysis and to define the area of application of various systems of heat supply. The principal decision based on the basis of the above analysis is the decision to install an independent or a centralized system of heat supply.

  16. Contribution of domestic heating systems to smart grid control

    DEFF Research Database (Denmark)

    Tahersima, Fatemeh; Stoustrup, Jakob; Meybodi, Soroush Afkhami

    2011-01-01

    How and to what extent, domestic heating systems can be helpful in regaining power balance in a smart grid, is the question to be answered in this paper. Our case study is an under-floor heating system supplied with a geothermal heat pump which is driven by electrical power from the grid. The idea...... is to deviate power consumption of the heat pump from its optimal value, in order to compensate power imbalances in the grid. Heating systems could be forced to consume energy, i.e. storing it in heat buffers when there is a power surplus in the grid; and be prevented from using power, in case of power shortage...

  17. Monitoring of a flat plate solar thermal field supplying process heat

    Directory of Open Access Journals (Sweden)

    Cozzini Marco

    2016-01-01

    Full Text Available The article reports the performance data of a flat plate collector field installed in Austria and supplying process heat to a meat factory, up to a temperature of about 95 °C. The presented data span an entire year, thereby including seasonal effects and allowing for a full characterization of the system performances. Sensor uncertainty is also discussed in detail. Finally, a bin method analysis of the field efficiency is provided. To this purpose, different operating conditions are concisely represented by the so-called reduced temperature, typically used in solar collector applications.

  18. Tree Seed and Seedling Supply Systems

    DEFF Research Database (Denmark)

    Nyoka, Betserai I.; Roshetko, James M.; Jamnadass, Ramni

    2015-01-01

    The paper reviews tree seed and seedling supply systems in sub-Saharan Africa, Asia and Latin America. Across these regions, the review found that some of the germplasm supply systems do not efficiently meet farmers’ demands and environmental expectations in terms of productivity, species...... and genetic diversity. In some countries, germplasm used is mostly sourced from undocumented sources and often untested. Germplasm quality control systems are only found in a few countries. Appreciation of the value of tree germplasm of high genetic quality is low. Non-government organisations (NGOs) in many...... out private entrepreneurs, although this is not substantiated by any evidence to suggest that the smallholder farmers are willing and able to pay for the germplasm. In some Latin American countries, private companies, government and NGOs provide farmers tree germplasm in a partnership in which farmers...

  19. Solar thermal energy / exhaust air heat pump / wood pellet furnace for a sustainable heat supply of low energy buildings in older buildings; Solarthermie / Abluft-Waermepumpe / Pelletofen. Kombisysteme zur nachhaltigen Waermeversorgung von Niedrigenergiehaeusern im Gebaeudebestand

    Energy Technology Data Exchange (ETDEWEB)

    Diefenbach, Nikolaus; Born, Rolf [Institut Wohnen und Umwelt GmbH, Darmstadt (Germany); Staerz, Norbert [Ingenieurbuero inPlan, Pfungstadt (Germany)

    2009-11-13

    The research project under consideration reports on combination systems for a sustainable heat supply for low-energy buildings in older building. For this, a central and decentralized system configuration consisting of solar thermal energy, exhaust air heat pump and wood pellet furnace are presented. Solutions for an interaction of these three heat suppliers in one plant are designated regarding the control strategy. The fundamentals of the computerized simulations for the central and decentralized system are presented. A cost estimate with both variants of the combination system as well as a comparison with conventional energy-saving heat supply systems follow.

  20. Ventilation and Heat Recovering System

    Directory of Open Access Journals (Sweden)

    Olga Bancea

    2007-01-01

    Full Text Available Some aspects concerning the heat reducing for ventilation, achieved by using heat recovering components and a combined heating--ventilating system, assuring both comfort and human health are presented. The floor imbedded systems together with air outlets elements could fulfill all the aesthetically desires, as well as comfort and they are ideal for family houses.

  1. SOME FEATURES OF THE POWER SUPPLY OF RESIDENTIAL BUILDINGS DURING THE HEATING SEASON

    Directory of Open Access Journals (Sweden)

    S. N. Osipov

    2017-01-01

    Full Text Available A large proportion of consumption of different types of energy by the residential sector, especially in the heating period, makes the energy efficiency of buildings without considering the loss of fuel with a significant reduction in hourly load on the generators, especially at night, already insufficient for real energy savings. Therefore in Belarus, in order to attract the consumer, electricity tariff for heating at night hours (from 11 p.m. to 6.00 a.m. is three times cheaper than at any other time. Significant increase of the electricity consumption of at night could be achieved by using heat accumulators for heating and hot water supply to the residential sector. Particularly effective are water accumulators of heat and accumulators of underfloor heating that enable to use a coolant with a temperature of 40 оC and to increase the useful supply of heat. The use of heat accumulators for daily heating, ventilation and hot water supply of buildings significantly reduces the cost of creating the infrastructure of the territory under construction by eliminating the necessity of running the distribution network of heat or gas supply. The use of the heat accumulators is necessary due to the increase of the time-weighted average outdoor temperature. The mentioned increase in the City of Minsk in the heating season is of about 0.1 °C per year in average, and as for the last 20 years, the increase has led to a reduction of the required heat load on the premises by about 10 %. Research and project work on choosing the most effective options for the arrangement and use the heat accumulators in buildings of the various functions ought to be fulfilled in order to make the application of heat accumulators successful. In this respect civil and power engineers as well as operators should work together so to determine the chronological, technical and economic conditions of charging and use of heat accumulators.

  2. Solar space-heating system--Yosemite National Park, California

    Science.gov (United States)

    1981-01-01

    A 12 months performance of Visitors Center installation suffered from low insolation, high energy dissipation, and equipment breakdown. System has 980 square feet of liquid flat-plate collectors, water energy storage, 4-mode control, heat exchangers, pumps, and plumbing. Design expected system to supply over 50 percent of annual heating demand, but only 109 million Btu were conserved.

  3. A solar heating system with annual storage

    Science.gov (United States)

    Lazzari, F.; Raffellini, G.

    1981-07-01

    A solar heated house with long term storage capability, built in Trento, Italy, is described. The one story house was built from modular components and has a total heated volume of 1130 cu m. Flat plate solar collectors with a water-antifreeze medium are located beneath the lawn, and six cylindrical underground tanks holding 130 cu m of water heated by thermal energy from the collectors are situated under the garden. The house walls have an 8 cm cavity filled with 5 cm of formaldehyde foam, yielding a heat transmission (U) of 0.37 W/sq m/deg C. The roof and ceilings are insulated with fiberglass and concrete, producing U-values of 0.46 W/sq m/deg C and 0.57 W/sq m/deg C, respectively. Heat pumps using 6 kW move thermal energy between the house and the tanks. Direct hot water heating occurs in the summer, and direct home heating when the stored water temperature exceeds 32 C. A computer model was developed which traces the annual heat flow and it is shown that the system supplies all heating requirements for the house, with electrical requirements equal to 20 percent of the annual house needs.

  4. The Optimization of Draining System of Heating Network in 350MW Supercritical Heat Supplying Unit%350MW超临界供热机组热网疏水系统优化

    Institute of Scientific and Technical Information of China (English)

    王卫良; 李永生

    2013-01-01

    The draining methods of drainage water from heating network heater in 350MW supercritical unit have been discussed.The problems and disadvantages of methods like directly drained into deaerator,drained into deaerator after deironing in high temperature and drained into condenser after cooling were pointed out.Method of drained into the steam side of LP heater has been proposed,and the effects of tiny heat loss,no need for drawing off of drainage water during startup and deironing in high temperature,no reevaporation in condenser and steady backpressure could be met.A case of rated heating condition has been calculated,and the loss of heat rate is only 0.27%.%对350MW超临界供热机组热网加热器疏水不同处理方案进行对比分析,指出直接去除氧器、高温除铁后进入除氧器、降温处理后进入凝汽器等方案存在的问题,提出了改进型热网疏水系统,即直接进入5号低加疏水侧.改进后可实现无启动放水、无高温除铁、无凝汽器二次蒸发和背压升高等效果.以某350MW机组额定采暖抽汽工况为对象,改进后系统损耗仅为机组热耗的0.27%.

  5. Schedule Planning for Repairing Power Supply System

    OpenAIRE

    Kuo-Wei Lin; Chein-Jen Kang

    2012-01-01

    Problem statement: Taiwan is located in the tropical ocean areas. The strong typhoon in summer often causes the collapse of electric transmission towers and results in power outages that seriously affect peoples lives and industrial production. Approach: In light of this situation, this study aims to employ project management techniques of Theory of Constraints (TOC) to develop a practical TOC model to quickly repair the towers and restore power supplied system. Results: The actual applicatio...

  6. Influence of Compressor Station Waste-Heat Recovery Section on Operational Efficiency of Gas Turbine Drive with Isobaric Heat Supply and Regenerative Heat Utilization

    Directory of Open Access Journals (Sweden)

    A. Nesenchuk

    2013-01-01

    Full Text Available The possibility to utilize existing secondary energy resources for heat supply of an industrial enterprise has been proposed on the basis of the analysis on operation of compressor stations of a cross-country gas pipe-line. The paper considers an influence of waste heat recovery section on operational efficiency of gas turbine drive with regenerative heat utilization.

  7. Supply Chain Systems Architecture and Engineering Design: Green-field Supply Chain Integration

    OpenAIRE

    Radanliev, Petar

    2015-01-01

    This paper developed a new theory for supply chain architecture, and engineering design that enables integration of the business and supply chain strategies. The architecture starts with individual supply chain participants and derives insights into the complex and abstract concept of green-field integration design. The paper presented a conceptual system for depicting the interactions between business and supply chain strategy engineering. The system examines the decisions made when engineer...

  8. Supply Chain Systems Architecture and Engineering Design: Green-field Supply Chain Integration

    OpenAIRE

    Radanliev, Petar

    2015-01-01

    This paper developed a new theory for supply chain architecture, and engineering design that enables integration of the business and supply chain strategies. The architecture starts with individual supply chain participants and derives insights into the complex and abstract concept of green-field integration design. The paper presented a conceptual system for depicting the interactions between business and supply chain strategy engineering. The system examines the decisions made when engineer...

  9. Optimized district heating supply temperature for large networks; Optimerad framledningstemperatur foer stora fjaerrvaermenaet

    Energy Technology Data Exchange (ETDEWEB)

    Saarinen, Lisa; Boman, Katarina

    2012-02-15

    The supply temperature of the Uppsala district heating network was optimized using a model-based control strategy. Simulation of the network showed that the supply temperature could be decreased by in average 8 deg and the electricity production of the plants supplying the network could be increased with 2.5 % during the period January- April, giving an extra income of 1.2 MSEK due to increased income from electricity sales

  10. Thermal control of power supplies with electronic packaging techniques. [using low cost heat pipes

    Science.gov (United States)

    1977-01-01

    The integration of low-cost commercial heat pipes in the design of a NASA candidate standard modular power supply with a 350 watt output resulted in a 44% weight reduction. Part temperatures were also appreciably reduced, increasing the environmental capability of the unit. A complete 350- watt modular power converter was built and tested to evaluate thermal performance of the redesigned supply.

  11. The Power Supply System for the J-TEXT Poloidal Field

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ming; ZHUANG Ge; YU Kexun; QiU Shengshun; PAN Yuan

    2009-01-01

    Joint-TEXT(J-TEXT)is a medium-sized tokamak constructed at Huazhong University of Science and Technology.At present,the poloidal field power supply consists of three subsystem sets,namely Ohmic heating field power supply,vertical field power supply,and horizontal field power supply.The structure and function of the poloidal field(PF)power supply aus well as the updated control system of the power supply is described.The new scheme uses the realtime feedback control method for the poloidal field power supply.The experimental results show that the poloidal field energized by poloidal field power supply meets the J-TEXT operational requirement perfectly.

  12. Numerical Investigation of Floor Heating Systems in Low Energy Houses

    DEFF Research Database (Denmark)

    Weitzmann, Peter; Kragh, Jesper; Jensen, Claus Franceos

    2002-01-01

    . The model calculates heating demand, room temperatures, and thermal comfort parameters for a person in the room. The model is based on a numerical Finite Control Volume (FCV) method for the heat transfer in walls, ceiling, windows and floor. The model uses both convective and radiative heat transfer...... – a heavy system integrated into the concrete floor and a light system which is placed in heat transfer plates – have been investigated, using different supply temperatures to the floor heating system, and different control strategies. The aim of the study is to compare the two types of floor heating......In this paper an investigation of floor heating systems is performed with respect to heating demand and room temperature. Presently (2001) no commercially available building simulation programs that can be used to evaluate heating demand and thermal comfort in buildings with building integrated...

  13. A modeling approach for district heating systems with focus on transient heat transfer in pipe networks

    DEFF Research Database (Denmark)

    Mohammadi, Soma; Bojesen, Carsten

    2015-01-01

    finite element method is applied to simulate transient temperature changes in pipe networks. The model is calculating time series data related to supply temperature to the DHN from heat production units, heat loads and return temperature related to each consumer to calculate dynamic temperature changes...... district heating networks [DHN] characteristics. This paper is presenting a new developed model, which reflects the thermo-dynamic behavior of DHN. It is designed for tree network topologies. The purpose of the model is to serve as a basis for applying a variety of scenarios towards lowering...... the temperature in DH systems. The main focus is on modeling transient heat transfer in pipe networks regarding the time delays between the heat supply unit and the consumers, the heat loss in the pipe networks and the consumers’ dynamic heat loads. A pseudo-dynamic approach is adopted and also the implicit...

  14. Indicators for Sustainable Energy Development for Austria (ISED-AT). Residential Buildings and Electricity and Heat Supply

    OpenAIRE

    Kettner, Claudia; Kletzan-Slamanig, Daniela; Köppl, Angela

    2015-01-01

    A transformation of prevailing energy systems requires adequate measurement systems. In this paper we propose an energy-service based indicator set and a composite index for monitoring sustainable energy development in the residential sector and electricity and heat supply in Austria. The system of Indicators for Sustainable Energy Development for Austria (ISED-AT) and the composite index focus on energy services instead of energy flows and are hence effective tools for monitoring and guiding...

  15. Economics of heat pump systems for simultaneous heating and cooling

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, S.; Devotta, S.; Patwardhan, V.S.

    1987-01-01

    Heat pumps can be incorporated advantageously into processes which require simultaneously both cooling and heating. The economics of heat pumps in India for simultaneous heat and cooling is assessed with respect to process, design and economic parameters. For the typical conditions of various parameters in India, a heat pump system for simultaneous heating and cooling is very attractive.

  16. Solar Heating System with Building-Integrated Heat Storage

    DEFF Research Database (Denmark)

    Heller, Alfred

    1996-01-01

    Traditional solar heating systems cover between 5 and 10% of the heat demand fordomestic hot water and comfort heating. By applying storage capacity this share can beincreased much. The Danish producer of solar heating systems, Aidt-Miljø, markets such a system including storage of dry sand heated...... by PP-pipe heat exchanger. Heat demand is reduced due to direct solar heating, and due to storage. Heat demand is reduced due to direct solar heating, due to storage and due to lower heat losses through the ground. In theory, by running the system flow backwards through the sand storage, active heating...... can be achieved.The objective of the report is to present results from measured system evaluation andcalculations and to give guidelines for the design of such solar heating systems with building integrated sand storage. The report is aimed to non-technicians. In another report R-006 the main results...

  17. Advanced Building Efficiency Testbed Initiative/Intelligent Workplace Energy Supply System; ABETI/IWESS

    Energy Technology Data Exchange (ETDEWEB)

    David Archer; Frederik Betz; Yun Gu; Rong Li; Flore Marion; Sophie Masson; Ming Qu; Viraj Srivastava; Hongxi Yin; Chaoqin Zhai; Rui Zhang; Elisabeth Aslanian; Berangere Lartigue

    2008-05-31

    ABETI/IWESS is a project carried out by Carnegie Mellon's Center for Building Performance and Diagnostics, the CBPD, supported by the U.S. Department of Energy/EERE, to design, procure, install, operate, and evaluate an energy supply system, an ESS, that will provide power, cooling, heating and ventilation for CBPD's Intelligent Workplace, the IW. The energy sources for this system, the IWESS, are solar radiation and bioDiesel fuel. The components of this overall system are: (1) a solar driven cooling and heating system for the IW comprising solar receivers, an absorption chiller, heat recovery exchanger, and circulation pump; (2) a bioDiesel fueled engine generator with heat recovery exchangers, one on the exhaust to provide steam and the other on the engine coolant to provide heated water; (3) a ventilation system including an enthalpy recovery wheel, an air based heat pump, an active desiccant wheel, and an air circulation fan; and (4) various convective and radiant cooling/heating units and ventilation air diffusers distributed throughout the IW. The goal of the ABETI/IWESS project is to demonstrate an energy supply system for a building space that will provide a healthy, comfortable environment for the occupants and that will reduce the quantity of energy consumed in the operation of a building space by a factor of 2 less than that of a conventional energy supply for power, cooling, heating, and ventilation based on utility power and natural gas fuel for heating.

  18. Ultracapacitor-Based Uninterrupted Power Supply System

    Science.gov (United States)

    Eichenberg, Dennis J.

    2011-01-01

    The ultracapacitor-based uninterrupted power supply (UPS) system enhances system reliability; reduces life-of-system, maintenance, and downtime costs; and greatly reduces environmental impact when compared to conventional UPS energy storage systems. This design provides power when required and absorbs power when required to smooth the system load and also has excellent low-temperature performance. The UPS used during hardware tests at Glenn is an efficient, compact, maintenance-free, rack-mount, pure sine-wave inverter unit. The UPS provides a continuous output power up to 1,700 W with a surge rating of 1,870 W for up to one minute at a nominal output voltage of 115 VAC. The ultracapacitor energy storage system tested in conjunction with the UPS is rated at 5.8 F. This is a bank of ten symmetric ultracapacitor modules. Each module is actively balanced using a linear voltage balancing technique in which the cell-to-cell leakage is dependent upon the imbalance of the individual cells. The ultracapacitors are charged by a DC power supply, which can provide up to 300 VDC at 4 A. A constant-voltage, constant-current power supply was selected for this application. The long life of ultracapacitors greatly enhances system reliability, which is significant in critical applications such as medical power systems and space power systems. The energy storage system can usually last longer than the application, given its 20-year life span. This means that the ultracapacitors will probably never need to be replaced and disposed of, whereas batteries require frequent replacement and disposal. The charge-discharge efficiency of rechargeable batteries is approximately 50 percent, and after some hundreds of charges and discharges, they must be replaced. The charge-discharge efficiency of ultracapacitors exceeds 90 percent, and can accept more than a million charges and discharges. Thus, there is a significant energy savings through the efficiency improvement, and there is far less

  19. Environmental inventories for future electricity supply systems for Switzerland

    Energy Technology Data Exchange (ETDEWEB)

    Dones, R.; Gantner, U.; Hirschberg, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Doka, G.; Knoepfel, I. [Eidgenoessische Technische Hochschule, Zurich (Switzerland)

    1996-02-01

    This report provides the analysis of environmental inventories for selected electricity supply systems considered as possible options to meet the expected electricity demand in Switzerland in year 2030. Two possible electricity demand level cases were postulated by VSE, both under the basic assumption of economic growth: a high-growth demand case corresponding to a yearly increase of 2% from year 1995 to year 2010 and 1% from year 2010 to year 2030, and a low-growth demand case corresponding to a yearly increase of 1% from year 1995 to year 2010 and 0.5% from year 2010 to year 2030. The base (i.e. secured) supply in year 2030 will be, according to VSE, totally dominated by hydro with rather minor contributions from combined heat-and-power plants, small gas turbines, incinerators and solar photovoltaic plants. Due to decommissioning of the currently operating nuclear power plants and expiration of long-term electricity import contracts there will eventually occur a gap between the postulated electricity demand and the base supply. VSE provided seven options to cover this gap, defined in terms of mixes with different contributions from gas, coal, nuclear and solar chains; in this context a distinction is also made with respect to shares of domestic and imported electricity. The systems considered represent advanced technologies, regarded as either typical or most suitable for the Swiss conditions. System-specific input to the present analysis has been partially generated based on direct contacts with the industry. Life Cycle Analysis (LCA) was used to establish environmental inventories for the systems analysed. The analysis has been performed on three levels:(1) individually for each system considered, (2) comparison of systems, (3) comparison of supply options. Results are also provided for these three levels.

  20. Synthesis of Flexible Heat Exchanger Networks with Stream Splits Based on Rangers of Stream Supply Temperatures and Heat Capacity Flowrates

    Institute of Scientific and Technical Information of China (English)

    李志红; 罗行; 华贵; W.Roetzel

    2004-01-01

    A new superstructure model of heat exchanger networks (HEN) with stream splits based on rangers of streams supply temperatures and heat capacity flow rates is presented. The simultaneous optimal mathematical model of flexible HEN synthesis is established too. Firstly, the streams with rangers of supply temperatures and/or the streams with the rangers of heat capacity flow rates are pretreated; Secondly, several rules are proposed to establish the superstructure model of HEN with splits and the simultaneous optimal mathematical model of flexible HEN; Thirdly, the improving genetic algorithm is applied to solve the mathematical model established at the second step effectively, and the original optimal structure of HEN based on the maximum operation limiting condition can be obtained easily; Finally, the rules of heat exchange unit merged and the heat load of heat exchanger relaxed are presented, the flexible configuration of HEN satisfied the operation condition between the upper and down bounds of supply temperature and heat capacity flow rates can be obtained based on the original optimal structure of HEN by means of these rules. A case study demonstrates the method presented in this paper is effective

  1. The electrohydraulic balance of the solar heat storage with autonomous power supply

    Directory of Open Access Journals (Sweden)

    M. K. Marahtanov

    2014-01-01

    Full Text Available The introduction of the paper emphasizes an increasingly important role of alternative power sources nowadays. At the same time, a solar collector (suntrap is one of the most frequent techniques to use the solar energy. It is an absorber that picks up solar radiation and heats a heat carrier circulating in the close loop. Then the heat is transferred to the heat accumulator that is integrated in the hot-tap water system (HWS.The paper presents a prospective circuit of the solar collector. It differs from the traditional one because, in addition to absorbing panel, it uses photoconverters to generate electric power for the circulating pump. The advantage of this system is that for operation such a solar energy converter has no need in external power sources, i.e. it is autonomous. The need to calculate the essential thermo-physical parameters that ensure no-break system operation was stated as a main objective of the work.The suggested circuit has a photocell panel to convert solar radiation into dc voltage of 12 V. In case of a lack of the solar energy an accumulator battery can be used for feeding. To ensure the no-break supply of power an adaptor is offered.To calculate a density distribution of solar radiation a sine law is offered depending on the time of day and geographical locality. This dependence was used to obtain the expressions for calculating the water temperature in boiler over daytime.Further, the calculations have been done for the operating conditions under which an efficient heat exchange will be provided with the minimum consumption of electric power for the heat carrier circulation in the first loop. For this purpose, a pump power was calculated depending on consumption and hydraulic losses of head in the pipeline. As a minimum required consumption the value has been chosen at which a laminar flow regime changes to the turbulent one because of the most efficient heat exchange being both in collector and in heat accumulator

  2. Lyapunov Criteria for Structural Stability of Supply Chain System

    Institute of Scientific and Technical Information of China (English)

    LU Ying-jin; TANG Xiao-wo; ZHOU Zong-fang

    2004-01-01

    In this paper, based on Cobb-Douglas production function, the structural stability of the supply chain system are analyzed by employing Lyapunov criteria. That the supply chain system structure,with the variance of the rate of re-production input funding, becomes unstable is proved. Noticeably, the solutions shows that when the optimal combination of input parameter element, the qualitative properties of supply chain system change and the supply chain system becomes unstable.

  3. Solar Heating Systems: Instructor's Guide.

    Science.gov (United States)

    Green, Joanne; And Others

    This Instructor's Guide for a Solar Heating System Curriculum is designed to accompany the Student Manual and the Progress Checks and Test Manual for the course (see note), in order to facilitate the instruction of classes on solar heating systems. The Instructor's Guide contains a variety of materials used in teaching the courses, including…

  4. Solar Heating Systems: Student Manual.

    Science.gov (United States)

    Green, Joanne; And Others

    This Student Manual for a Solar Heating System curriculum contains 22 units of instructional materials for students to use in a course or courses on solar heating systems (see note). For each unit (task), objectives, assignment sheets, laboratory assignments, information sheets, checkpoints (tests), and job sheets are provided. Materials are set…

  5. Artesian water supply control system in transient conditions

    Directory of Open Access Journals (Sweden)

    Костянтин Олегович Буравченко

    2016-06-01

    Full Text Available The paper describes an artesian water supply control system in the transition mode. The control system searches for the optimal performance trajectory of the water supply on the basis of a maximum return with a view to the fastest mode of stabilization. The analysis of artesian water supply control systems in transition mode and methods of improvement was conducted

  6. Geothermal heating systems for greenhouses

    Energy Technology Data Exchange (ETDEWEB)

    Silva, J.F.; Johnson, W.C.

    1980-08-12

    Ways to utilize low-temperature geothermally heated water for a flow-through system are presented. The geothermal energy used for this system is the waste heat discharged from space heating 500,000 square feet of floor space at Oregon Institute of Technology with geothermal water pumped directly from the campus wells. The information collected and analyzed is from data developed from operating a greenhouse on the Oregon Institute of Technology campus from December 1979 to April 1980. Methods for calculating heating requirements of greenhouses using geothermal energy were developed from the analyses of the data obtained. (MHR)

  7. Retrofitting Combined Space and Water Heating Systems. Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B. [NorthernStar Building America Partnership, St. Paul, MN (United States); Bohac, D. [NorthernStar Building America Partnership, St. Paul, MN (United States); Huelman, P. [NorthernStar Building America Partnership, St. Paul, MN (United States); Olsen, R. [NorthernStar Building America Partnership, St. Paul, MN (United States); Hewett, M. [NorthernStar Building America Partnership, St. Paul, MN (United States)

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  8. Retrofitting Combined Space and Water Heating Systems: Laboratory Tests

    Energy Technology Data Exchange (ETDEWEB)

    Schoenbauer, B.; Bohac, D.; Huelman, P.; Olson, R.; Hewitt, M.

    2012-10-01

    Better insulated and tighter homes can often use a single heating plant for both space and domestic water heating. These systems, called dual integrated appliances (DIA) or combination systems, can operate at high efficiency and eliminate combustion safety issues associated by using a condensing, sealed combustion heating plant. Funds were received to install 400 DIAs in Minnesota low-income homes. The NorthernSTAR DIA laboratory was created to identify proper system components, designs, operating parameters, and installation procedures to assure high efficiency of field installed systems. Tests verified that heating loads up to 57,000 Btu/hr can be achieved with acceptable return water temperatures and supply air temperatures.

  9. Residential solar-heating system-design package

    Science.gov (United States)

    1979-01-01

    Design package for modular solar heating system includes performance specifications, design data, installation guidelines, and other information that should be valuable to those interested in system (or similar systems) for projected installation. When installed in insulated "energy saver" home, system can supply large percentage of total energy needs of building.

  10. Residential solar-heating system-design package

    Science.gov (United States)

    1979-01-01

    Design package for modular solar heating system includes performance specifications, design data, installation guidelines, and other information that should be valuable to those interested in system (or similar systems) for projected installation. When installed in insulated "energy saver" home, system can supply large percentage of total energy needs of building.

  11. Power supply system for negative ion source at IPR

    Energy Technology Data Exchange (ETDEWEB)

    Gahlaut, Agrajit; Sonara, Jashwant; Parmar, K G; Soni, Jignesh; Bandyopadhyay, M; Singh, Mahendrajit; Bansal, Gourab; Pandya, Kaushal; Chakraborty, Arun, E-mail: agrajit@ipr.res.i [Institute for Plasma Research, Gandhinagar, Gujarat - 382428 (India)

    2010-02-01

    The first step in the Indian program on negative ion beams is the setting up of Negative ion Experimental Assembly - RF based, where 100 kW of RF power shall be coupled to a plasma source producing plasma of density {approx}5 x 10{sup 12} cm{sup -3}, from which {approx} 10 A of negative ion beam shall be produced and accelerated to 35 kV, through an electrostatic ion accelerator. The experimental system is modelled similar to the RF based negative ion source, BATMAN presently operating at IPP, Garching, Germany. The mechanical system for Negative Ion Source Assembly is close to the IPP source, remaining systems are designed and procured principally from indigenous sources, keeping the IPP configuration as a base line. High voltage (HV) and low voltage (LV) power supplies are two key constituents of the experimental setup. The HV power supplies for extraction and acceleration are rated for high voltage ({approx}15 to 35kV), and high current ({approx} 15 to 35A). Other attributes are, fast rate of voltage rise (< 5ms), good regulation (< {+-}1%), low ripple (< {+-}2%), isolation ({approx}50kV), low energy content (< 10J) and fast cut-off (< 100{mu}s). The low voltage (LV) supplies required for biasing and providing heating power to the Cesium oven and the plasma grids; have attributes of low ripple, high stability, fast and precise regulation, programmability and remote operation. These power supplies are also equipped with over-voltage, over-current and current limit (CC Mode) protections. Fault diagnostics, to distinguish abnormal rise in currents (breakdown faults) with over-currents is enabled using fast response breakdown and over-current protection scheme. To restrict the fault energy deposited on the ion source, specially designed snubbers are implemented in each (extraction and acceleration) high voltage path to swap the surge energy. Moreover, the monitoring status and control signals from these power supplies are required to be electrically ({approx} 50k

  12. Fault tolerant system design for uninterruptible power supplies

    OpenAIRE

    B. Y. Volochiy; D. S. Kuznetsov

    2012-01-01

    The problem of design for reliability of a fault tolerant system for uninterruptible power supplies is considered. Configuration of a fault tolerant system determines the structure of an uninterruptible power supply: power supply built from modules of the same type, stand-by sliding reserve for them, twice total reserve of the power supply with two accumulator batteries, the controls and diagnostics means. The developed tool for automated analytical model of fault tolerant systems generation ...

  13. Floor-supply displacement air-conditioning system; Zenmen yuka fukidashi kucho system ni kansuru gijutsu kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Takebayashi, Y.; Nobe, T. [Shimizu Corp., Tokyo (Japan); Hatanaka, H. [Nitto Boseki Co. Ltd., Tokyo (Japan); Tanabe, S. [Waseda University, Tokyo (Japan)

    1999-11-05

    This development is proposing an alternative air-conditioning method, 'floor-supply displacement air-conditioning system'. The idea comes from the principle of displacement ventilation originally, using breathable carpet tiles laid over a perforated raised floor system. In this system, fresh cool or heated air are supplied at very low velocity throughout the carpet tiles. This system has been applied to 25 buildings and total floor area reached 10,000m{sup 2}. (author)

  14. Utilization of solar energy. Solar thermal heating systems; Die Waerme vom Himmel holen. Solarthermische Systeme

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2012-07-01

    Solar thermal power plants collect solar heat by means of collectors. Thus, solar thermal power plants support the heating and supply warm water for the showers. The implementation of solar thermal power plants is interesting especially for the exchange of the heating system as well as in the new house.

  15. Residential heat pumps in the future Danish energy system

    DEFF Research Database (Denmark)

    Petrovic, Stefan; Karlsson, Kenneth Bernard

    2016-01-01

    Denmark is striving towards 100% renewable energy system in 2050. Residential heat pumps are expected to be a part of that system.We propose two novel approaches to improve the representation of residential heat pumps: Coefficients of performance (COPs) are modelled as dependent on air and ground...... temperature while installation of ground-source heat pumps is constrained by available ground area. In this study, TIMES-DK model is utilised to test the effects of improved modelling of residential heat pumps on the Danish energy system until 2050.The analysis of the Danish energy system was done...... for politically agreed targets which include: at least 50% of electricity consumption from wind power starting from 2020, fossil fuel free heat and power sector from 2035 and 100% renewable energy system starting from 2050. Residential heat pumps supply around 25% of total residential heating demand after 2035...

  16. Ground Source Heat Pump in Heating System with Electronics Monitoring

    Directory of Open Access Journals (Sweden)

    NEAMŢU Ovidiu

    2013-10-01

    Full Text Available The monitoring system is implemented for a ground coupled heat pump in heating/ system. The borehole heat exchangers – which are 150 m long - are filled with a mixture of water and ethilene glycol calledbrine. Metering and monitoring energy consumption is achieved for: heat pump, circulation pumps, additional electrical heating, hot air ventilation systems, control systems with sensors: analog and smart sensors. Instantaneous values are stored in a local computer.

  17. Design and Analysis of the Poloidal Field Grid Power Supply System for the HT-7 Tokamak

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    This paper reports a new project - the poloidal field (PF) grid power supply system to replace the ac flywheel generator power supply system on the basis of the present running parameters of the HT-7 poloidal field and the short-circuit capacity of our transformer substation.The designed parameters of the PF grid power supply system have been verified to meet the requirements of the heating field (HF) and the vertical field (VF). In the meantime, in order to reduce the disturbance to the local power grid, the device of reactive power and harmonic current compensation has been added. Experimental results have confirmed the feasibility of the PF grid power supply system. Compared with the ac flywheel generator, the PF grid power supply system has the advantages of lower noise, precise control, convenient maintenance, simple operation and cost savings.

  18. District heating: lifeblood system systematically modernised; Lebensnerv Fernwaerme gezielt modernisiert

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This article discusses the high potential available for the reduction of operating costs in the distribution of heat to consumers via district heating networks. The modernisation of the district heating system in the Black Sea Port of Konstanza, Rumania, is discussed. In particular, the renewal of the hot-water circulation pumps and the implementation of an automated system for the control and monitoring of 132 district heating transfer stations is described. The system's functions - the supply of space heating and domestic hot water preparation - are looked at, as is its load-dependent control system and its associated communication system. The new pump speed control system is quoted as being able to permit savings of up to 60% to be made. Finally, the contributions to protecting the environment resulting from the renewal of the district heating system are noted.

  19. Schedule Planning for Repairing Power Supply System

    Directory of Open Access Journals (Sweden)

    Kuo-Wei Lin

    2012-01-01

    Full Text Available Problem statement: Taiwan is located in the tropical ocean areas. The strong typhoon in summer often causes the collapse of electric transmission towers and results in power outages that seriously affect peoples lives and industrial production. Approach: In light of this situation, this study aims to employ project management techniques of Theory of Constraints (TOC to develop a practical TOC model to quickly repair the towers and restore power supplied system. Results: The actual application had verified that the research model could not only shorten the duration of work but also save the manpower and material expenses. Conclusion: It once again proved the excellent results of reparation operations by applying TOC to project management.

  20. Study on cascade type underground heat storage, solar space heating system in Tehran (Part 2)

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Yasutaka; Kaabi-Nejadian, A.; Ito, Yukio

    1987-12-01

    This paper describes the cascade type underground heat storage, solar space-heating system using capsule-form latent heat storage material in Tehran. The coefficient of performance of the system and a used heat pump (HP), the solar collecting efficiency, and the effect of six variation factors on heat recovery from soil were subjected to variance analysis. For the heat recovery from soil, the operation time of HP was significant. For the solar collecting efficiency, the collector area was significant. As for short-period thermal behaviours, two operations of the system different in HP operation time on February 7th were sampled. The wind quantity and operation time of the space-heating fan, though they were not statistically significant, were effective for space-heating depending on thermal load to the system, since the fan can supply a large quantity of heat for space-heating. The temperature of the Kernel tank, the intermediate tank (latent heat), and the outermost tank (sesible heat) was decreased in that order. The temperture of the outermost tank was remarkably decreased during HP operation, so that heat-recovery was conducted. (5 figs, 4 tabs, 3 refs)

  1. Supply Chain as Complex Adaptive System and Its Modeling

    Institute of Scientific and Technical Information of China (English)

    MingmingWang

    2004-01-01

    Supply chain is a complex, hierarchical, integrated, open and dynamic network.Every node in the network is an independent business unit that unites other organizations to develop its value, the competition and cooperation between these units are basic impetus of the development and evolution of the supply chain system. The characteristics of supply chain as a complex adaptive system and its modeling are discussed in this paper, and use an example demonstrating the feasibility of CAS modeling in supply chain management study.

  2. Projecting demand and supply of forest biomass for heating in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Tromborg, Erik, E-mail: erik.tromborg@umb.no [Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, P.O. Box 5003, NO-1432 As (Norway); Havskjold, Monica; Lislebo, Ole [Xrgia as, P.O. Box 329, NO-1301, Sandvika (Norway); Rorstad, Per Kristian [Norwegian University of Life Sciences, Department of Ecology and Natural Resource Management, P.O. Box 5003, NO-1432 As (Norway)

    2011-11-15

    This paper assesses the increase in demand and supply for forest biomass for heating in Norway in 2020. By then there is a political aim to double the national production of bioenergy from the level in 2008. The competitiveness of woody biomass in central and district heating is analyzed in a model selecting the least-cost heating technology and scale in municipalities given a set of constraints and under different fuels price scenarios. The supply of forest biomass from roundwood is estimated based on data of forest inventories combined with elasticities regarding price and standing volumes. The supply of biomass from harvesting residues is estimated in an engineering approach based on data from the national forest inventories and roundwood harvest. The results show how the production of bioenergy is affected by changes in energy prices and support schemes for bioenergy. One conclusion from the analyses is that the government target of 14 TWh more bioenergy by 2020 is not likely to be met by current technologies and policy incentives. The contribution of the analysis is the detailed presentation of the heat market potentials and technology choices combined with supply functions for both roundwood and harvesting residues. - Highlights: > This paper accesses the demand and supply for forest biomass for heating in Norway in 2020. > Market share for wood in central and new district heating is analyzed in a cost-minimizing model. > The supply of forest biomass includes wood chips from import, roundwood and harvesting residues. > The production of bioenergy is affected by changes in energy prices and support schemes. > The government target for bioenergy is not met by current technologies and policy incentives.

  3. Design of the power supply system for the plasma current modulation on J-TEXT tokamak

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, M.; Shao, J.; Ma, S.X., E-mail: mashaoxiang@hust.edu.cn; Liang, X.; Yu, K.X.; Pan, Y.

    2016-10-15

    Highlights: • A modification scheme of heating field power supply system for plasma current modulation. • High-power fast control power supply with multilevel cascade circuit. • Restraining circulating current with coupled inductors in cyclic symmetric structure. - Abstract: In order to further study the influence of current modulation parameters on suppressing tearing instability, the plasma current should be modulated in a wider range. So a modification scheme is designed to improve the performance of ohmic heating power supply system on J-TEXT tokamak. A multilevel cascade circuit with carrier phase-shifted PWM technique has been proposed. Coupled inductors are connected in the form of cyclic symmetry to restrain the circulating current caused by multiple paralleled branches. The simulation proves this proposed current modulation power supply system matches output requirement and achieves good current sharing effect. Finally, a prototype is designed, and the experiment results can verify the correctness of the simulation model well.

  4. Primary energy savings using heat storage for biomass heating systems

    Directory of Open Access Journals (Sweden)

    Mitrović Dejan M.

    2012-01-01

    Full Text Available District heating is an efficient way to provide heat to residential, tertiary and industrial users. The heat storage unit is an insulated water tank that absorbs surplus heat from the boiler. The stored heat in the heat storage unit makes it possible to heat even when the boiler is not working, thus increasing the heating efficiency. In order to save primary energy (fuel, the boiler operates on nominal load every time it is in operation (for the purpose of this research. The aim of this paper is to analyze the water temperature variation in the heat storage, depending on the heat load and the heat storage volume. Heat load is calculated for three reference days, with average daily temperatures from -5 to 5°C. The primary energy savings are also calculated for those days in the case of using heat storage in district heating.[Projekat Ministarstva nauke Republike Srbije, br. TR 33051: The concept of sustainable energy supply of settlements with energy efficient buildings

  5. Reduced heat stress in offices in the tropics using solar powered drying of the supply air

    DEFF Research Database (Denmark)

    Gunnarsen, Lars; Santos, A M B

    2002-01-01

    Many solutions to indoor climate problems known from developed countries may have prohibitive installation and running costs in developing countries. The purpose was to develop a low-cost solution to heat stress in a hot and humid environment based on solar powered drying of supply air. Dry supply...... combinations of temperature and humidity and led to Personal Units for Ventilation and Cooling (PUVAC) in six cubicles simulating office workplaces. A total of 123 heat acclimatized subjects were exposed 45 min in each of the cubicles. A model for the combined effect of operative temperature of room, moisture...

  6. Boise geothermal district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, P.J.

    1985-10-01

    This document describes the Boise geothermal district heating project from preliminary feasibility studies completed in 1979 to a fully operational system by 1983. The report includes information about the two local governments that participated in the project - the City of Boise, Idaho and the Boise Warm Springs Water District. It also discusses the federal funding sources; the financial studies; the feasibility studies conducted; the general system planning and design; design of detailed system components; the legal issues involved in production; geological analysis of the resource area; distribution and disposal; the program to market system services; and the methods of retrofitting buildings to use geothermal hot water for space heating. Technically this report describes the Boise City district heating system based on 170/sup 0/F water, a 4000 gpm production system, a 41,000 foot pipeline system, and system economies. Comparable data are also provided for the Boise Warm Springs Water District. 62 figs., 31 tabs.

  7. Geothermal source heat pump performance for a greenhouse heating system: an experimental study

    Directory of Open Access Journals (Sweden)

    Alexandros Sotirios Anifantis

    2016-09-01

    Full Text Available Greenhouses play a significant function in the modern agriculture economy even if require great amount of energy for heating systems. An interesting solution to alleviate the energy costs and environmental problems may be represented by the use of geothermal energy. The aim of this paper, based on measured experimental data, such as the inside greenhouse temperature and the heat pump performance (input and output temperatures of the working fluid, electric consumption, was the evaluation of the suitability of low enthalpy geothermal heat sources for agricultural needs such as greenhouses heating. The study was carried out at the experimental farm of the University of Bari, where a greenhouse was arranged with a heating system connected to a ground-source heat pump (GSHP, which had to cover the thermal energy request. The experimental results of this survey highlight the capability of the geothermal heat source to ensue thermal conditions suitable for cultivation in greenhouses even if the compressor inside the heat pump have operated continuously in a fluctuating state without ever reaching the steady condition. Probably, to increase the performance of the heat pump and then its coefficient of performance within GSHP systems for heating greenhouses, it is important to analyse and maximise the power conductivity of the greenhouse heating system, before to design an expensive borehole ground exchanger. Nevertheless, according to the experimental data obtained, the GSHP systems are effective, efficient and environmental friendly and may be useful to supply the heating energy demand of greenhouses.

  8. CBTL Design Case Summary Conventional Feedstock Supply System - Herbaceous

    Energy Technology Data Exchange (ETDEWEB)

    Christopher T. Wright; Erin M. Searcy

    2012-02-01

    A conventional bale feedstock design has been established that represents supply system technologies, costs, and logistics that are achievable today for supplying herbaceous feedstocks as a blendstock with coal for energy production. Efforts are made to identify bottlenecks and optimize the efficiency and capacities of this supply system, within the constraints of existing local feedstock supplies, equipment, and permitting requirements. The feedstock supply system logistics operations encompass all of the activities necessary to move herbaceous biomass feedstock from the production location to the conversion reactor ready for blending and insertion. This supply system includes operations that are currently available such that costs and logistics are reasonable and reliable. The system modeled for this research project includes the uses of field-dried corn stover or switchgrass as a feedstock to annually supply an 800,000 DM ton conversion facility.

  9. Utilization of the horizontal ground heat exchanger in the heating and cooling system of a residential building

    Directory of Open Access Journals (Sweden)

    Hanuszkiewicz-Drapała Małgorzata

    2016-03-01

    Full Text Available This paper presents the results of thermodynamic analyses of a system using a horizontal ground heat exchanger to cool a residential building in summer and heat it in the autumn-winter period. The main heating device is a vapour compression heat pump with the ground as the lower heat source. The aim of the analyses is to examine the impact of heat supply to the ground in the summer period, when the building is cooled, on the operation of the heating system equipped with a heat pump in the next heating season, including electricity consumption. The processes occurring in cooling and heating systems have an unsteady nature. The main results of the calculations are among others the time-dependent values of heat fluxes extracted from or transferred to the ground heat exchanger, the fluxes of heat generated by the heat pump and supplied to the heated building by an additional heat source, the parameters in characteristic points of the systems, the temperature distributions in the ground and the driving electricity consumption in the period under analysis. The paper presents results of analysis of cumulative primary energy consumption of the analyzed systems and cumulative emissions of harmful substances.

  10. Utilization of the horizontal ground heat exchanger in the heating and cooling system of a residential building

    Science.gov (United States)

    Hanuszkiewicz-Drapała, Małgorzata; Bury, Tomasz

    2016-03-01

    This paper presents the results of thermodynamic analyses of a system using a horizontal ground heat exchanger to cool a residential building in summer and heat it in the autumn-winter period. The main heating device is a vapour compression heat pump with the ground as the lower heat source. The aim of the analyses is to examine the impact of heat supply to the ground in the summer period, when the building is cooled, on the operation of the heating system equipped with a heat pump in the next heating season, including electricity consumption. The processes occurring in cooling and heating systems have an unsteady nature. The main results of the calculations are among others the time-dependent values of heat fluxes extracted from or transferred to the ground heat exchanger, the fluxes of heat generated by the heat pump and supplied to the heated building by an additional heat source, the parameters in characteristic points of the systems, the temperature distributions in the ground and the driving electricity consumption in the period under analysis. The paper presents results of analysis of cumulative primary energy consumption of the analyzed systems and cumulative emissions of harmful substances.

  11. ENERGY-EFFICIENT REGIMES FOR HEATING-SUPPLY OF THE RESIDENTIAL BUILDINGS

    Directory of Open Access Journals (Sweden)

    S. N. Osipov

    2015-01-01

    Full Text Available Rise in comfort and inhabitation safety is one of the main requirements of the general maintenance, reconstruction of the old and construction of the new residential houses. One of the essential factors of it is substitution in the household hot-water preparing sources: from the individual domestic gas  water-heaters to  the common  entire-building hot-water supply at the expense of the centralized heat supply. Extremely erratic hot-water daily consumption by tenants leads to the necessity of sharp increase in central heat-supply level during a few hours of the day, which requires a significant increase of the source heat-power. On that score, the authors propose to direct a significant part (up to 50 % of the centralized heating and ventilation heat power-consumption to the hot water preparation during the period of short-term hot water consumption peak.Substitution  of  the  individual  domestic  gas  water-heaters  with  the  common  entirebuilding hot-water supply releases a huge amount of natural gas which can be utilized not only for production of the necessary heat power but as well for electric power producing. This substitution is especially advantageous if heat-power is delivered to the residential area from a НРС where significant part of heat especially in a relatively warm season of the year is thrown out into the air. The content of the article is based on several patents received earlier.

  12. Prototype solar heating and combined heating cooling systems

    Science.gov (United States)

    1978-01-01

    The design and development of eight prototype solar heating and combined heating and cooling systems is discussed. The program management and systems engineering are reported, and operational test sites are identified.

  13. Simulation of Production Lines Supply within Internal Logistics Systems

    Science.gov (United States)

    Čujan, Zdeněk

    2016-11-01

    Supplying of production lines is a complex logistic process, which is very difficult with regards to the requirements of its operation and scheduling. For this reason, this supplying process demands an increased attention. Application of a computer simulation is an efficient tool suitable for solution of the supplying logistic questions. In this paper the application possibilities of the software Tecnomatix Plant Simumlation specified for simulation of the supplying process by means of the system Milk Run will be presented.

  14. A cost optimization model for 100% renewable residential energy supply systems

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2012-01-01

    for the interdependencies between the different supply technologies as well as the construction energy of the installations, consumption profiles and on-site energy resource availability. This paper aims at developing such a model for the optimal sizing of renewable energy supply systems (RES) for residential Net ZEB......'s involving on-site production of heat and electricity in combination with electricity exchanged with the public grid. The model is based on linear programming and determines the optimal capacities for each relevant supply technology in terms of the overall system costs. It has been successfully applied...

  15. Heat Transfer Parametric System Identification

    Science.gov (United States)

    1993-06-01

    Transfer Parametric System Identification 6. AUTHOR(S Parker, Gregory K. 7. PERFORMING ORGANIZATION NAME(S) AND AOORESS(ES) 8. PERFORMING ORGANIZATION...distribution is unlimited. Heat Transfer Parametric System Identification by Gregory K. Parker Lieutenant, United States Navy BS., DeVry Institute of...Modeling Concept ........ ........... 3 2. Lumped Parameter Approach ...... ......... 4 3. Parametric System Identification ....... 4 B. BASIC MODELING

  16. Electricity and heat supply of a settlement at different standards of energy efficiency; Strom- und Waermeversorgung einer Siedlung bei unterschiedlichen Energieeffizienz-Standards

    Energy Technology Data Exchange (ETDEWEB)

    Schuberth, Jens; Tschetschorke, Katja

    2013-07-15

    The underlying study analyses the ecologic impact and the economic efficiency of several conventional and innovative heat supply systems to provide a quarter heat for space and water heating and electricity for residential and commercial application and for street lighting. Retrofits of buildings change the ratio of demands for electricity and heat. The demand for heat decreases more than the demand for electricity, and the share of distribution losses in heat grids rises. The question is if it is still economically efficient to build or extend local and long-distance district heating networks. Demands for final and primary energy, greenhouse gas emissions and costs (for operation, energy consumption and investments) of the different systems are compared and rated both in charts and tables. A sensitivity analysis includes increasing energy purchasing costs and assesses the possible economic efficiency of the supply systems in future. Another sensitivity analysis estimates how the climate impact of the supply systems for heat and electricity changes if electricity generation becomes less harmful for climate. Additionally, costs for environmental damage - so-called external costs - are internalised in the analysis of economic efficiency. In an overall rating ecologic and economically efficient systems are recommended.

  17. Thermal deformation in a thin circular plate due to a partially distributed heat supply

    Indian Academy of Sciences (India)

    N L Khobragade; K C Deshmukh

    2005-08-01

    In this paper, we develop an integral transform to determine temperature distribution in a thin circular plate, subjected to a partially distributed and axisymmetric heat supply on the curved surface, and study the thermal deformation. The results, obtained in series form in terms of Bessel’s functions, are illustrated numerically.

  18. Fuel Application Efficiency in Ideal Cycle of Gas Turbine Plant with Isobaric Heat Supply

    Directory of Open Access Journals (Sweden)

    A. Nesenchuk

    2013-01-01

    Full Text Available The paper reveals expediency to use in prospect fuels with maximum value  Qнр∑Vi and minimum theoretical burning temperature in order to obtain maximum efficiency of the ideal cycle in GTP with isobaric heat supply.

  19. Largest fluidized bed power plant unit for power and district heat supply for Berlin (Part 1)

    Energy Technology Data Exchange (ETDEWEB)

    Abroell, G.; Bade, H.; Bietz, K.H.; Jahn, P. (ABB Kraftwerke AG, Mannheim (Germany))

    1991-11-01

    The Berlin Power and Light Company (Bewag) has decided to install, on the inner city site of Moabit, for the supply of electricity and district heating, a new unit with circulating atmospheric fluidized bed combustion. The plant will be designed for a thermal capacity of 240 MW. The basis for this decision, and also the technical implementation, will be made public.

  20. Performance of Chilled Beam with Radial Swirl Jet and Diffuse Ceiling Air Supply in Heating Mode

    DEFF Research Database (Denmark)

    Bertheussen, Bård; Mustakallio, Panu; Melikov, Arsen Krikor

    2013-01-01

    The performance of diffuse ceiling air supply and chilled beam with swirl jet (CSW) in heating mode (winter situation) was studied and compared with regard to the generated indoor environment. An office mock-up with one occupant was simulated in a test room (4.5 x 3.95 x 3.5 m3 (L x W x H...

  1. Limiting biomass consumption for heating in 100% renewable energy systems

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik; Connolly, David

    2012-01-01

    The utilisation of biomass poses large challenges in renewable energy systems while buildings account for a substantial part of the energy supply even in 100% renewable energy systems. In this paper the focus is on how the heating sector can reduce its consumption of biomass, thus leaving biomass...... for other sectors, but while still enabling a 100% renewable energy system. The analyses of heating technologies shows that district heating (DH) systems are important in limiting the dependence on biomass and create cost effective solutions. DH systems are especially important in renewable energy systems...... with large amounts of fluctuating sources as it enables fuel efficient and low cost energy systems with thermal heat storages. DH increases the efficiency with the use of combined heat and power production (CHP), while reducing the biomass demand by enabling the use of other renewable resources such as large...

  2. Solar technology assessment project. Volume 3: Active space heating and hot water supply with solar energy

    Science.gov (United States)

    Karaki, S.; Loef, G. O. G.

    1981-04-01

    Several types of solar water heaters are described and assessed. These include thermosiphon water heaters and pump circulation water heaters. Auxiliary water heating is briefly discussed, and new and retrofit systems are compared. Liquid-based space heating systems and solar air heaters are described and assessed, auxiliary space heating are discussed, and new and retrofit solar space heating systems are compared. The status of flat plate collectors, evacuated tube collectors, and thermal storage systems is examined. Systems improvements, reliability, durability and maintenance are discussed. The economic assessment of space and water heating systems includes a comparison of new systems costs with conventional fuels, and sales history and projections. The variety of participants in the solar industry and users of solar heat is discussed, and various incentives and barriers to solar heating are examined. Several policy implications are discussed, and specific government actions are recommended.

  3. Magnetically switched power supply system for lasers

    Science.gov (United States)

    Pacala, Thomas J. (Inventor)

    1987-01-01

    A laser power supply system is described in which separate pulses are utilized to avalanche ionize the gas within the laser and then produce a sustained discharge to cause the gas to emit light energy. A pulsed voltage source is used to charge a storage device such as a distributed capacitance. A transmission line or other suitable electrical conductor connects the storage device to the laser. A saturable inductor switch is coupled in the transmission line for containing the energy within the storage device until the voltage level across the storage device reaches a predetermined level, which level is less than that required to avalanche ionize the gas. An avalanche ionization pulse generating circuit is coupled to the laser for generating a high voltage pulse of sufficient amplitude to avalanche ionize the laser gas. Once the laser gas is avalanche ionized, the energy within the storage device is discharged through the saturable inductor switch into the laser to provide the sustained discharge. The avalanche ionization generating circuit may include a separate voltage source which is connected across the laser or may be in the form of a voltage multiplier circuit connected between the storage device and the laser.

  4. CBTL Design Case Summary Conventional Feedstock Supply System - Woody

    Energy Technology Data Exchange (ETDEWEB)

    Christopher T. Wright; Erin M. Searcy

    2012-02-01

    A conventional woody feedstock design has been developed that represents supply system technologies, costs, and logistics that are achievable today for supplying woody biomass as a blendstock with coal for energy production. Efforts are made to identify bottlenecks and optimize the efficiency and capacities of this supply system, within the constraints and consideration of existing local feedstock supplies, equipment, and permitting requirements. The feedstock supply system logistics operations encompass all of the activities necessary to move woody biomass from the production location to the conversion reactor ready for blending and insertion. This supply system includes operations that are currently available such that costs and logistics are reasonable and reliable. The system modeled for this research project includes the use of the slash stream since it is a more conservative analysis and represents the material actually used in the experimental part of the project.

  5. IEA Response System for Oil Supply Emergencies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-12-15

    Emergency response to oil supply disruptions has remained a core mission of the International Energy Agency since its founding in 1974. This information pamphlet explains the decisionmaking process leading to an IEA collective action, the measures available -- focusing on stockdraw -- and finally, the historical background of major oil supply disruptions and the IEA response to them. It also demonstrates the continuing need for emergency preparedness, including the growing importance of engaging key transition and emerging economies in dialogue about energy security.

  6. IEA Response System for Oil Supply Emergencies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-15

    Emergency response to oil supply disruptions has remained a core mission of the International Energy Agency since its founding in 1974. This information pamphlet explains the decisionmaking process leading to an IEA collective action, the measures available -- focusing on stockdraw -- and finally, the historical background of major oil supply disruptions and the IEA response to them. It also demonstrates the continuing need for emergency preparedness, including the growing importance of engaging key transition and emerging economies in dialogue about energy security.

  7. Estimation of low-potential heat recuperation efficiency of smoke fumes in a condensation heat utilizer under various operation conditions of a boiler and a heating system

    Science.gov (United States)

    Ionkin, I. L.; Ragutkin, A. V.; Luning, B.; Zaichenko, M. N.

    2016-06-01

    For enhancement of the natural gas utilization efficiency in boilers, condensation heat utilizers of low-potential heat, which are constructed based on a contact heat exchanger, can be applied. A schematic of the contact heat exchanger with a humidifier for preheating and humidifying of air supplied in the boiler for combustion is given. Additional low-potential heat in this scheme is utilized for heating of the return delivery water supplied from a heating system. Preheating and humidifying of air supplied for combustion make it possible to use the condensation utilizer for heating of a heat-transfer agent to temperature exceeding the dewpoint temperature of water vapors contained in combustion products. The decision to mount the condensation heat utilizer on the boiler was taken based on the preliminary estimation of the additionally obtained heat. The operation efficiency of the condensation heat utilizer is determined by its structure and operation conditions of the boiler and the heating system. The software was developed for the thermal design of the condensation heat utilizer equipped by the humidifier. Computation investigations of its operation are carried out as a function of various operation parameters of the boiler and the heating system (temperature of the return delivery water and smoke fumes, air excess, air temperature at the inlet and outlet of the condensation heat utilizer, heating and humidifying of air in the humidifier, and portion of the circulating water). The heat recuperation efficiency is estimated for various operation conditions of the boiler and the condensation heat utilizer. Recommendations on the most effective application of the condensation heat utilizer are developed.

  8. ENSURING THERMAL REGIME FOR THE SUPPLY DISTRIBUTED DEVICES IN THE COMPOSITION OF THE SHIP'S SECONDARY POWER SUPPLY SYSTEMS ON THE BASE OF THE STANDARDIZED UNITS

    Directory of Open Access Journals (Sweden)

    T. A. Ismailov

    2016-01-01

    Full Text Available Aim. The article deals with the problem of constructing the power supply devices in the composition of the ship's secondary power systems based on standardized blocks and securing their thermal regime.Methods. It is stated that with the advent of modern power electronics multifunctional components the secondary power supply developers got possibilities to improve the quality of secondary power supply and to upgrade the existing systems.Results. The advantages of unified power units, having a function of parallel operation are revealed. Heat transfer processes in a vertical channel with free convection, and the calculation of the minimum width of the channel, which provides efficient heat removal have been analyzed.Conclusion.A model is proposed for determining the minimum distance between the blocks without deterioration of heat transfer in the channel formed by the walls of adjacent blocks.

  9. Westinghouse Small Modular Reactor nuclear steam supply system design

    Energy Technology Data Exchange (ETDEWEB)

    Memmott, M. J.; Harkness, A. W.; Van Wyk, J. [Westinghouse Electric Company LLC, 600 Cranberry Woods Drive, Cranberry Twp. PA 16066 (United States)

    2012-07-01

    The Westinghouse Small Modular Reactor (SMR) is an 800 MWt (>225 MWe) integral pressurized water reactor (iPWR), in which all of the components typically associated with the nuclear steam supply system (NSSS) of a nuclear power plant are incorporated within a single reactor pressure vessel. This paper is the first in a series of four papers which describe the design and functionality of the Westinghouse SMR. Also described in this series are the key drivers influencing the design of the Westinghouse SMR and the unique passive safety features of the Westinghouse SMR. Several critical motivators contributed to the development and integration of the Westinghouse SMR design. These design driving motivators dictated the final configuration of the Westinghouse SMR to varying degrees, depending on the specific features under consideration. These design drivers include safety, economics, AP1000{sup R} reactor expertise and experience, research and development requirements, functionality of systems and components, size of the systems and vessels, simplicity of design, and licensing requirements. The Westinghouse SMR NSSS consists of an integral reactor vessel within a compact containment vessel. The core is located in the bottom of the reactor vessel and is composed of 89 modified Westinghouse 17x17 Robust Fuel Assemblies (RFA). These modified fuel assemblies have an active core length of only 2.4 m (8 ft) long, and the entirety of the core is encompassed by a radial reflector. The Westinghouse SMR core operates on a 24 month fuel cycle. The reactor vessel is approximately 24.4 m (80 ft) long and 3.7 m (12 ft) in diameter in order to facilitate standard rail shipping to the site. The reactor vessel houses hot and cold leg channels to facilitate coolant flow, control rod drive mechanisms (CRDM), instrumentation and cabling, an intermediate flange to separate flow and instrumentation and facilitate simpler refueling, a pressurizer, a straight tube, recirculating steam

  10. Heat Pumps in CHP Systems

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt

    in Danish conditions. The limitations are highly dependent on the integration of heat source and sink streams. An evaluation of feasible operating conditions was carried out considering the constraints of available refrigeration equipment and a requirement of a positive net present value of the investment...... goals. The presented study investigates the possible introduction of HPs from both a thermodynamic and a system/operation management perspective, in order to find optimal integration schemes in both current and future energy scenarios. Five generic configurations of HPs in district heating (DH) systems...... that three configurations are particular advantageous, whereas the two remaining configurations result in system performance close to or below what may be expected from an electric heater. One of the three advantageous configurations is required to be positioned at the location of the heat demand, whereas...

  11. Implementing Geothermal Plants in the Copenhagen District Heating System

    DEFF Research Database (Denmark)

    Jensen, Louise Overvad; Hallgreen, Christine Erikstrup; Larsen, Esben

    2003-01-01

    The possibility of implementing geothermal heating in the Copenhagen district-heating system is assessed. This is done by building up general knowledge on the geological factors that influence the development of useable geothermal resources, factors concerning the exploration and utilization...... Danish district heating system is financially sustainable. Added to the other advantages concerning flexibility and the environment, geothermal heating is considered to be a serious proposal for the future power and heating system in Eastern Denmark. Keywords: Geothermal plants, Electricity surplus...... of geothermal energy in Denmark as well as the Danish potential, which, in former investigations, has been found to be around 100.000 PJ annually, and the economical potential is less, about 15 PJ/year. Since a considerable amount of the Danish power supply is tied to weather and the demand for heating...

  12. Implementing Geothermal Plants in the Copenhagen District Heating System

    DEFF Research Database (Denmark)

    Jensen, Louise Overvad; Hallgreen, Christine Erikstrup; Larsen, Esben

    2003-01-01

    Danish district heating system is financially sustainable. Added to the other advantages concerning flexibility and the environment, geothermal heating is considered to be a serious proposal for the future power and heating system in Eastern Denmark. Keywords: Geothermal plants, Electricity surplus......The possibility of implementing geothermal heating in the Copenhagen district-heating system is assessed. This is done by building up general knowledge on the geological factors that influence the development of useable geothermal resources, factors concerning the exploration and utilization...... of geothermal energy in Denmark as well as the Danish potential, which, in former investigations, has been found to be around 100.000 PJ annually, and the economical potential is less, about 15 PJ/year. Since a considerable amount of the Danish power supply is tied to weather and the demand for heating...

  13. Energy savings for solar heating systems; Solvarmeanlaegs energibesparelser

    Energy Technology Data Exchange (ETDEWEB)

    Furbo, S.; Fan, J.

    2011-01-15

    Energy savings for a number of new solar heating systems in one family houses have been determined by means of information on the energy consumption of the houses before and after installation of the solar heating systems. The investigated solar heating systems are marketed by Velux Danmark A/S, Sonnnenkraft Scandinavia A/S and Batec Solvarme A/S. Solar domestic hot water systems as well as solar combi systems are included in the investigations The houses have different auxiliary energy supply systems: Natural gas boilers, oil fired burners, electrical heating and district heating. Some of the houses have a second auxiliary energy supply system. The collector areas vary from 1.83 m{sup 2} to 9.28 m{sup 2}. Some of the solar heating systems are based on energy units with a new integrated natural gas boiler and a heat storage for the solar heating system. The existing energy systems in the houses are for most of the houses used as the auxiliary energy systems for the solar heating systems. The yearly energy savings for the houses where the only change is the installation of the solar heating system vary from 300 kWh per m{sup 2} solar collector to 1300 kWh per m{sup 2} solar collector. The average yearly energy savings is about 670 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector are not influenced by the solar heating system type, the company marketing the system, the auxiliary energy supply system, the collector area, the collector tilt, the collector azimuth, the energy consumption of the house or the location of the house. The yearly energy savings for the houses with solar heating systems based on energy units including a new natural gas boiler vary from 790 kWh per m{sup 2} solar collector to 2090 kWh per m{sup 2} solar collector. The average yearly energy savings is about 1520 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector for

  14. Power supply devices and systems of relay protection

    CERN Document Server

    Gurevich, Vladimir

    2013-01-01

    Power Supply Devices and Systems of Relay Protection brings relay protection and electrical power engineers a single, concentrated source of information on auxiliary power supply systems and devices. The book also tackles specific problems and solutions of relay protection power supply systems and devices, which are often not dealt with in the literature. The author, an experienced engineer with more than 100 patents, draws on his own experience to offer practical, tested advice to readers. A Guide to Relay Protection Power Supply for Engineers and Technicians The first chapter reviews the ele

  15. Fault tolerant system design for uninterruptible power supplies

    Directory of Open Access Journals (Sweden)

    B. Y. Volochiy

    2012-02-01

    Full Text Available The problem of design for reliability of a fault tolerant system for uninterruptible power supplies is considered. Configuration of a fault tolerant system determines the structure of an uninterruptible power supply: power supply built from modules of the same type, stand-by sliding reserve for them, twice total reserve of the power supply with two accumulator batteries, the controls and diagnostics means. The developed tool for automated analytical model of fault tolerant systems generation and illustration of its capabilities in determination of requirements for repair service and accumulator batteries are given.

  16. Flexible Workflow Management in Agile Supply Chain System

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With the vehement development of global competition , Agile Supply Chain (ASC) becomes an effective approach that supports dynamic ent erprise alliance and realizes agile manufacturing, as for the enterprises to cap ture market opportunities rapidly and strengthen their anti-risk ability. As Ag ile Supply Chain System (ASCS) is dynamic and distributed, the realization of it 's processes needs to be much flexible. Often in Agile Supply Chain System (ASCS ), there are many dynamic tasks, many changes of the ...

  17. Life Cycle Multi-Criteria Analysis Of Alternative Energy Supply Systems For A Residential Building

    Directory of Open Access Journals (Sweden)

    Artur Rogoža

    2013-12-01

    Full Text Available The article analyses energy supply alternatives for a partially renovated residential building. In addition to the existing district heating (base case alternative systems, gas boilers, heat pumps (air-water and ground-water, solar collectors, solar cells, and combinations of these systems have been examined. Actual heat consumption of the building and electricity demand determined by the statistical method are used for simulating the systems. The process of simulation is performed using EnergyPro software. In order to select an optimal energy supply option, the life cycle analysis of all systems has been carried out throughout a life span of the building, and the estimated results of energy, environmental and economic evaluation have been converted into non-dimensional variables (3E using multi–criteria analysis.Article in Lithuanian

  18. The development of a solar residential heating and cooling system

    Science.gov (United States)

    1975-01-01

    The MSFC solar heating and cooling facility was assembled to demonstrate the engineering feasibility of utilizing solar energy for heating and cooling buildings, to provide an engineering evaluation of the total system and the key subsystems, and to investigate areas of possible improvement in design and efficiency. The basic solar heating and cooling system utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating, and an absorption cycle air conditioner for space cooling. A complete description of all systems is given. Development activities for this test system included assembly, checkout, operation, modification, and data analysis, all of which are discussed. Selected data analyses for the first 15 weeks of testing are included, findings associated with energy storage and the energy storage system are outlined, and conclusions resulting from test findings are provided. An evaluation of the data for summer operation indicates that the current system is capable of supplying an average of 50 percent of the thermal energy required to drive the air conditioner. Preliminary evaluation of data collected for operation in the heating mode during the winter indicates that nearly 100 percent of the thermal energy required for heating can be supplied by the system.

  19. Heat of fusion storage systems for combined solar systems in low energy buildings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Furbo, Simon

    2004-01-01

    Solar heating systems for combined domestic hot water and space heating has a large potential especially in low energy houses where it is possible to take full advantage of low temperature heating systems. If a building integrated heating system is used – e.g. floor heating - the supply temperatu...... the storage is in its super cooled phase without activation of the phase change. This paper presents an initial simulation model of a PCM storage for implementation in TRNSYS 15 [1] as well as the first test results achieved with the model....

  20. Exergoeconomic optimization of an ammonia-water hybrid heat pump for heat supply in a spray drying facility

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Markussen, Wiebke Brix; Reinholdt, Lars

    2014-01-01

    Spray drying facilities are among the most energy intensive industrial processes. Using a heat pump to recover waste heat and replace gas combustion has the potential to attain both economic and emissions savings. In the case examined a drying gas of ambient air is heated to 200 XC. The inlet flow...... rate is 100,000 m3/h which yields a heat load of 6.1 MW. The exhaust air from the drying process is 80 XC. The implementation of an ammonia-water hybrid absorption-compression heat pump to partly cover the heat load is investigated. A thermodynamic analysis is applied to determine optimal circulation...... ratios for a number of ammonia mass fractions and heat pump loads. An exergoeconomic optimization is applied to minimize the lifetime cost of the system. Technological limitations are applied to constrain the solution to commercial components. The best possible implementation is identified in terms...

  1. Optimization of Regulation Valve Location for Heating System

    Institute of Scientific and Technical Information of China (English)

    LIU Ling-ling; CHEN Hong-bing; LI De-ying

    2009-01-01

    This paper mainly studied how to determine the best location of the self-operated flow control valve at the heating system entrance.Since the location of regulating valve directly affects the pipe network per-formance,the simulation and analysis of pressure change in heating system WaS carried out with ComputationalFluid Dynamics(CFD)software.The study shows the best location of regulating valve varies with the change of the supply and return pipe length when the heating area of each user is small,and when the heating area of each user is large(2000000~3000000m2),the best location is on the supply pipe.

  2. Thermoelectricity in Self-Contained Heating and Boiler Systems

    Science.gov (United States)

    Anatychuk, L. I.; Mykhailovsky, V. Ya.; Strutynska, L. T.

    2010-09-01

    The use of thermoelectric generators (TEGs) in heating systems enables autonomous supply of power to automatic safety devices, creation of optimized gas mixtures, and automation and precise temperature control of exhaust gas and heat carriers. It is particularly important to make heating systems independent of the district electric grid. Results of research and development efforts on a TEG for supplying power to electric devices of self-contained heating and boiler systems are presented. A TEG physical model is proposed, and results of computer simulation and optimization of its basic power and design parameters are given. Two TEG design variants (single and double sided) are considered. Their advantages and shortcomings are discussed. On the basis of theoretical calculations, a prototype TEG for a 10.5-kW boiler is built. At water heating system temperatures from 35°C to 80°C, the TEG electric power is 50 W to 65 W, which is used to supply a circulation pump for forced liquid heat carrier delivery (30 W to 40 W) and a fan for removal of fuel combustion products from the boiler’s smoke chamber (5 W to 7 W).

  3. Standard sample supply system; Hyojun shiryo kyokyu system

    Energy Technology Data Exchange (ETDEWEB)

    Osaka, S. [Center for Coal Utilization Japan, Tokyo (Japan)

    1997-03-20

    More than 20 universities and research institutes participate in the study of developing basic technology of coal utilization, and the `Standard sample supply system` prepares, keeps and supplys standard samples so that common samples can be used in the study. Coal samples of 50 to 100 will be prepared for 5 years. A coal sample is about 160 kg. The samples are collected from coal yards of big consumers such as power stations, etc. and coal suppliers. How to smash and keep coal are also described. Main facilities and machinery and their specification are given. Each standard sample is analyzed by means of the coal and ash analysis method of JIS and the data are distributed. The items of the analysis are shown in table. A database system will be prepared by the end of 1996. 2 figs., 2 tabs.

  4. Sourcing and pricing strategies for two retailers in a decentralized supply chain system under supply disruption

    Directory of Open Access Journals (Sweden)

    M.A. Azarmehr

    2012-01-01

    Full Text Available This paper presents the decentralized supply chain with two suppliers and two competing retailers. It also investigates the sourcing and pricing strategies of two retailers in a decentralized supply chain system under a supply disruption environment. These retailers face their individual stochastic demand markets; however, they compete with each other through a two-stage price and service operation. The interactive dynamics among retailers is characterized, including the existence and uniqueness of the Nash Equilibrium in service and price games demonstrated.

  5. 24 CFR 3280.704 - Fuel supply systems.

    Science.gov (United States)

    2010-04-01

    ...), shall be delivered from the system into the gas supply connection. (b) LP-gas containers—(1) Maximum... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Fuel supply systems. 3280.704 Section 3280.704 Housing and Urban Development Regulations Relating to Housing and Urban Development...

  6. 30 CFR 36.27 - Fuel-supply system.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fuel-supply system. 36.27 Section 36.27 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF... Construction and Design Requirements § 36.27 Fuel-supply system. (a) Fuel tank. (1) The fuel tank shall...

  7. Microflora of drinking water distributed through decentralized supply systems (Tomsk)

    Science.gov (United States)

    Khvaschevskaya, A. A.; Nalivaiko, N. G.; Shestakova, A. V.

    2016-03-01

    The paper considers microbiological quality of waters from decentralized water supply systems in Tomsk. It has been proved that there are numerous microbial contaminants of different types. The authors claim that the water distributed through decentralized supply systems is not safe to drink without preliminary treatment.

  8. A supply chain approach to biochar systems [Chapter 2

    Science.gov (United States)

    Nathaniel M. Anderson; Richard D. Bergman; Deborah S. Page-Dumroese

    2017-01-01

    Biochar systems are designed to meet four related primary objectives: improve soils, manage waste, generate renewable energy, and mitigate climate change. Supply chain models provide a holistic framework for examining biochar systems with an emphasis on product life cycle and end use. Drawing on concepts in supply chain management and engineering, this chapter presents...

  9. Research of Agile Supply Chain Management Decision Support System

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Agile Supply Chain Management (ASCM) is an important topic and has received much attention recently.ASCM is a new management technology.Agile Supply Chain Management Decision Support System (ASCM-DSS) is presented.Firstly, agile supply chain management technology is introduced.Secondly a decision support system for agile supply chain management is proposed.Then, the implementation of ASCM-DSS in enterprise is discussed.Finally, a fuzzy intelligence decision-making process in Shanghai Turbine Generator Company (STGC) is described in detail.

  10. Heat supply from municipal solid waste incineration plants in Japan: Current situation and future challenges.

    Science.gov (United States)

    Tabata, Tomohiro; Tsai, Peii

    2016-02-01

    The use of waste-to-energy technology as part of a municipal solid waste management strategy could reduce the use of fossil fuels and contribute to prevention of global warming. In this study, we examined current heat and electricity production by incineration plants in Japan for external use. Herein, we discuss specific challenges to the promotion of heat utilisation and future municipal solid waste management strategies. We conducted a questionnaire survey to determine the actual conditions of heat production by incineration plants. From the survey results, information of about 498 incineration plants was extracted. When we investigated the relationship between heat production for external use and population density where incineration plants were located, we found that regions with a population density heat. We also found that external use of such energy for factories, markets, and related use, was noted in cities with a population density of 2000 to 4000 persons (km(2))(-1). Several incineration plants have poor performance for heat production because there are few facilities near them to provide demand for the energy. This is the result of redundant capacity, and is reflected in the heat production performance. Given these results, we discussed future challenges to creating energy demand around incineration plants where there is presently none. We also examined the challenges involved in increasing heat supply beyond the present situation.

  11. Prototype solar-heating system

    Science.gov (United States)

    1978-01-01

    Complete air-collector system to meet needs of single-family dwelling is designed to operate in any region of United States except extreme north and south. Design can be scaled up or down to accomodate wide range of heating and hot-water requirements for single-family, multi-family, or commercial buildings without significantly changing design concept.

  12. A cost optimization model for 100% renewable residential energy supply systems

    DEFF Research Database (Denmark)

    Milan, Christian; Bojesen, Carsten; Nielsen, Mads Pagh

    2012-01-01

    's involving on-site production of heat and electricity in combination with electricity exchanged with the public grid. The model is based on linear programming and determines the optimal capacities for each relevant supply technology in terms of the overall system costs. It has been successfully applied......The concept of net zero energy buildings (Net ZEB) has received increased attention throughout the last years. A well adapted and optimized design of the energy supply system is crucial for the performance of these buildings. To achieve this, a holistic approach is needed which accounts...... for the interdependencies between the different supply technologies as well as the construction energy of the installations, consumption profiles and on-site energy resource availability. This paper aims at developing such a model for the optimal sizing of renewable energy supply systems (RES) for residential Net ZEB...

  13. A heating system for piglets in farrowing house using waste heat from biogas engine

    Directory of Open Access Journals (Sweden)

    Payungsak Junyusen

    2008-12-01

    Full Text Available The aim of this study is to design and test a heating system for piglets in farrowing house by utilising the waste heat from a biogas engine as a heat source. The study was separated into three parts: the study on the biogas combined heat and power plant, the investigation on the properties of the heat panel, and the installation and testing of the heating system. From the experiment, the condition producing 60 kW of electrical power was a proper one, in which electrical efficiency and specific fuel consumption were 14% and 1.22 m3/kWh respectively. Generating both electricity and heat increased the overall efficiency to 37.7% and decreased the specific fuel consumption to 0.45 m3/kWh. The heat panel, which was made of a plastic material, had a thermal conductivity of 0.58 W/mC and the maximum compressive force and operating pressure of 8.1 kN and 0.35 bar respectively. The surface temperature of the panel was dependent on the inlet water temperature. When hot water of 44C was supplied into the farrowing house with room temperature of 26C, the average surface temperature was 33C. The developed heating system could provide heat for 4.3 farrowing houses. The payback period of this project was 2.5 years.

  14. How to prevent legionella infestation. Pt. 1. Central freshwater heating systems; Wie man Legionellen vermeiden. T. 1. Zentrale Trinkwassererwaermungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, Robert [DVGW-Fachausschuss Trinkwasserhygiene in Gebaeuden, Leverkusen (Germany)

    2009-01-15

    The contribution focuses on hygienically safe freshwater heating. Legionella prophylaxis is discussed, as are new findings concerning practical implementation of new requirements on modern freshwater supply systems. (orig.)

  15. Vapor phase heat transport systems

    Energy Technology Data Exchange (ETDEWEB)

    Hedstrom, J.C.; Neeper, D.A.

    1985-09-01

    This report describes progress in theoretical and experimental investigations of various forms of a vapor transport system for solar space heating, which could also be applied to service water heating. Refrigerant is evaporated in a solar collector, which may be located on the external wall or roof of a building. The vapor is condensed in a passively discharged thermal storage unit located within the building. The condensed liquid can be returned to the collector either by a motor-driven pump or by a completely passive self-pumping mechanism in which the vapor pressure lifts the liquid from the condenser to the collector. The theoretical investigation analyzes this self-pumping scheme. Experiments in solar test cells compare the operation of both passive and active forms of the vapor system with the operation of a passive water wall. The vapor system operates as expected, with potential advantages over other passive systems in design flexibility and energy yield.

  16. Innovations in the supply chain and construction engineering of nuclear-based heat transfer components

    Energy Technology Data Exchange (ETDEWEB)

    Perales, A. [Equipos Nucleares, S.A. - Ensa, Jose Ortega y Gasset, 28006 Madrid (Spain); Woolf, G. [Tecnicas Reunidas - TR, Arapiles, 28014 Madrid (Spain)

    2010-07-01

    Equipos Nucleares S.A. (Ensa) and Tecnicas Reunidas S.A. (TR), both long-established Spanish companies, have brought together innovative approaches for the supply of heat transfer solution packages by combining their respective experiences in heat exchanger design (TR), manufacturing (Ensa), and nuclear materials procurement (Ensa and TR), thereby founding a new potent European component supplier for nuclear power plants with over 50 years of experience in the global nuclear market. The combined strategy of the Ensa-TR association which addresses the problems currently faced by nuclear component suppliers is described herein. (authors)

  17. Combined solar heat and power system with a latent heat storage - system simulations for an economic assessment

    Science.gov (United States)

    Zipf, Verena; Neuhäuser, Anton

    2016-05-01

    Decentralized solar combined heat and power (CHP) systems can be economically feasible, especially when they have a thermal storage. In such systems, heat provided by solar thermal collectors is used to generate electricity and useful heat for e.g. industrial processes. For the supply of energy in times without solar irradiation, a thermal storage can be integrated. In this work, the performance of a solar CHP system using an active latent heat storage with a screw heat exchanger is investigated. Annual yield calculations are conducted in order to calculate annual energy gains and, based on them; economic assumptions are used to calculated economic numbers in order to assess the system performance. The energy savings of a solar system, compared to a system with a fossil fuel supply, are calculated. Then the net present value and the dynamic payback are calculated with these savings, the initial investment costs and the operational costs. By interpretation and comparison of these economic numbers, an optimum system design in terms of solar field size and storage size was determined. It has been shown that the utilization of such systems can be economical in remote areas without gas and grid connection. Optimal storage design parameters in terms of the temperature differences in the heat exchanger and the storage capacity have been determined which can further increase the net present value of such system.

  18. Exergoeconomic optimization of an ammonia–water hybrid absorption–compression heat pump for heat supply in a spraydrying facility

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Markussen, Wiebke Brix; Reinholdt, Lars

    2015-01-01

    load of 6.1 MW. The exhaust air from the drying process is 80 C. The implementation of anammonia–water hybrid absorption–compression heat pump to partly cover the heat load is investigated. A thermodynamic analysis is applied to determine optimal circulation ratios for a number of ammonia mass...... fractions and heat pump loads. An exergo economic optimization is applied to minimize the lifetime cost of the system. Technological limitations are imposed to constrain the solution to commercial components. The best possible implementation is identified in terms of heat load, ammonia mass fraction...

  19. JIT supply chain; an investigation through general system theory

    Directory of Open Access Journals (Sweden)

    O P Mishra

    2013-03-01

    Full Text Available This paper explains theoretical approach of the four theories of General system Theory (GST developed by Yourdon (1989 [Yourdon, E. (1989. Modern Structured Analysis. Yourdon Press, Prentice-Hall International, Englewood Cliffs, New Jersey. Senge] while applying it in information technology and subsequently used by caddy (2007 [Caddy I.N., & Helou, M.M. (2007. Supply chains and their management: Application of general systems theory. Journal of Retailing and Consumer Services, 14, 319–327.] in field of supply chain and management. JIT philosophy in core activities of supply chain i.e. procurement, production processes, and logistics are discussed through general system theory. The growing structure of the supply chain poses the implication restrictions and requires a heavy support system, many times a compromise is done while implementing JIT. The study would be useful to understand the general trends generated naturally regarding the adoption of the JIT philosophy in the supply chain.

  20. Heat pipe cooled reactors for multi-kilowatt space power supplies

    Energy Technology Data Exchange (ETDEWEB)

    Ranken, W.A.; Houts, M.G.

    1995-01-01

    Three nuclear reactor space power system designs are described that demonstrate how the use of high temperature heat pipes for reactor heat transport, combined with direct conversion of heat to electricity, can result in eliminating pumped heat transport loops for both primary reactor cooling and heat rejection. The result is a significant reduction in system complexity that leads to very low mass systems with high reliability, especially in the power range of 1 to 20 kWe. In addition to removing heat exchangers, electromagnetic pumps, and coolant expansion chambers, the heat pipe/direct conversion combination provides such capabilities as startup from the frozen state, automatic rejection of reactor decay heat in the event of emergency or accidental reactor shutdown, and the elimination of single point failures in the reactor cooling system. The power system designs described include a thermoelectric system that can produce 1 to 2 kWe, a bimodal modification of this system to increase its power level to 5 kWe and incorporate high temperature hydrogen propulsion capability, and a moderated thermionic reactor concept with 5 to 20 kWe power output that is based on beryllium modules that thermally couple cylindrical thermionic fuel elements (TFEs) to radiator heat pipes.

  1. Heat pipe cooled reactors for multi-kilowatt space power supplies

    Science.gov (United States)

    Ranken, W. A.; Houts, M. G.

    Three nuclear reactor space power system designs are described that demonstrate how the use of high temperature heat pipes for reactor heat transport, combined with direct conversion of heat to electricity, can result in eliminating pumped heat transport loops for both primary reactor cooling and heat rejection. The result is a significant reduction in system complexity that leads to very low mass systems with high reliability, especially in the power range of 1 to 20 kWe. In addition to removing heat exchangers, electromagnetic pumps, and coolant expansion chambers, the heat pipe/direct conversion combination provides such capabilities as startup from the frozen state, automatic rejection of reactor decay heat in the event of emergency or accidental reactor shutdown, and the elimination of single point failures in the reactor cooling system. The power system designs described include a thermoelectric system that can produce 1 to 2 kWe, a bimodal modification of this system to increase its power level to 5 kWe and incorporate high temperature hydrogen propulsion capability, and a moderated thermionic reactor concept with 5 to 20 kWe power output that is based on beryllium modules that thermally couple cylindrical thermionic fuel elements (TFE's) to radiator heat pipes.

  2. Naval Logistics Integration Through Interoperable Supply Systems

    Science.gov (United States)

    2014-06-13

    Air Ground Task Force Materiel Distribution Center MOADT Mean Outside Assistance Delay Time MRO Material Release Order MSRT Mean Supply Response...within GCSS-MC only) for subsequent processing. After pick release ran, GCSS-MC sent Web-STRATIS a Material Release Orders ( MRO ) (also referred to...as a pick) via the Web-STRATIS outbound interface.18 Upon receipt of the MROs , warehouse personnel were able to view the requests in Web- STRATIS and

  3. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... that combines different energy sources for heat production will be used. The work has been carried out in scope of 4th Generation District Heating Technologies and Systems project.......District heating system could contribute to more efficient heat generation through cogeneration power plants or waste heat utilization facilities and to increase of renewable energy sources share in total energy consumption. In the most developed EU countries, renewable energy sources have been...

  4. The effects of air leaks on solar air heating systems

    Science.gov (United States)

    Elkin, R.; Cash, M.

    1979-01-01

    This paper presents the results of an investigation to determine the effects of leakages in collector and duct work on the system performance of a typical single-family residence solar air heating system. Positive (leakage out) and negative (leakage in) pressure systems were examined. Collector and duct leakage rates were varied from 10 to 30 percent of the system flow rate. Within the range of leakage rates investigated, solar contribution to heated space and domestic hot water loads was found to be reduced up to 30 percent from the no-leak system contribution with duct leakage equally divided between supply and return duct; with supply duct leakage greater than return leakage a reduction of up to 35 percent was noted. The negative pressure system exhibited a reduction in solar contribution somewhat larger than the positive pressure system for the same leakage rates.

  5. Regenerative Heat Usage of Gas-Turbine Units with Isobar Heat Supply

    Directory of Open Access Journals (Sweden)

    A. V. Begliak

    2010-01-01

    Full Text Available The paper considers problems concerning optimization of gas turbine operational modes at varying loads due to regeneration application. The possibility pertaining to increase of operational efficiency gas-turbine units at various modes is shown in the paper. The efficiency can be achieved due to an increase of regeneration rate while reducing consumer’s heat load.

  6. ENERGY SUPPLY OF COMMERTIAL GREENHOUSE WITH THE GAS DRIVEN HEAT PUMP part II

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2013-12-01

    Full Text Available In this article a scheme of connection of heat exchanger for utilization of heat of flue gases to evaporator is proposed. In proposed scheme is ensured the minimum power of ventilator for air’s feeding to the evaporator of heat pump and compensation of pulsations of temperature of flue gases and pressure of ventilator. It is shown how to optimize parameters of heat exchanger in conditions of minimum of dissipation of energy with utilization of value of entransy. It is elaborated a scheme of coordinated control system of hydraulic transmissions, that transfers power on compressor of heat pump and electrical generator.

  7. Agent-based modelling of heating system adoption in Norway

    Energy Technology Data Exchange (ETDEWEB)

    Sopha, Bertha Maya; Kloeckner, Christian A.; Hertwich, Edgar G.

    2010-07-01

    Full text: This paper introduces agent-based modelling as a methodological approach to understand the effect of decision making mechanism on the adoption of heating systems in Norway. The model is used as an experimental/learning tool to design possible interventions, not for prediction. The intended users of the model are therefore policy designers. Primary heating system adoptions of electric heating, heat pump and wood pellet heating were selected. Random topology was chosen to represent social network among households. Agents were households with certain location, number of peers, current adopted heating system, employed decision strategy, and degree of social influence in decision making. The overall framework of decision-making integrated theories from different disciplines; customer behavior theory, behavioral economics, theory of planned behavior, and diffusion of innovation, in order to capture possible decision making processes in households. A mail survey of 270 Norwegian households conducted in 2008 was designed specifically for acquiring data for the simulation. The model represents real geographic area of households and simulates the overall fraction of adopted heating system under study. The model was calibrated with historical data from Statistics Norway (SSB). Interventions with respects to total cost, norms, indoor air quality, reliability, supply security, required work, could be explored using the model. For instance, the model demonstrates that a considerable total cost (investment and operating cost) increase of electric heating and heat pump, rather than a reduction of wood pellet heating's total cost, are required to initiate and speed up wood pellet adoption. (Author)

  8. Conducting Sanitary Surveys of Water Supply Systems. Student Workbook.

    Science.gov (United States)

    1976

    This workbook is utilized in connection with a 40-hour course on sanitary surveys of water supply systems for biologists, chemists, and engineers with experience as a water supply evaluator. Practical training is provided in each of the 21 self-contained modules. Each module outlines the purpose, objectives and content for that section. The course…

  9. Development of city water supply net information system

    Institute of Scientific and Technical Information of China (English)

    CHENJing; GUOShiquan; LUJun

    2003-01-01

    Through analyzing the present conditions of water supply networks technical administration files in Chongqing, this paper points out the significance and urgency for exploiting advanced water supply networks information system. It also gives the concept of GIS and some suggestions for the exploitation.

  10. Supply Chain Resilience: Assessing USAF Weapon System Life Cycle

    Science.gov (United States)

    2010-03-01

    Appendix E: Supply Chain Resilience Storyboard ........................................................... 87 Bibliography...bolt that, in March 2000, struck a Philips semiconductor plant in Albuquerque, New Mexico , created a 10-minute blaze that contaminated millions of...strategic planning of weapon systems as they mature and progress through the life cycle. 87 Appendix E: Supply Chain Resilience Storyboard 88

  11. Reno Industrial Park geothermal district heating system

    Energy Technology Data Exchange (ETDEWEB)

    Lienau, P.J.

    1997-04-01

    Ten miles south of Reno, on U.S. 395 near the junction of the road to historic Virginia City, is Steamboat Hot Springs, a popular stop for travelers since the mid-1800s. Legend has it that Mark Twain named the geothermal area because it looked and sounded like a chugging Mississippi River paddle-wheeler. It is said when he first saw the steam rising from the ground he exclaimed, {open_quotes}Behold! A Steamboat in the desert.{close_quotes} Over the years, the area has been used for its relaxing and curative qualities by Indians, settlers, and geothermal experts. Since the mid-1980s five geothermal power plants have been built at Steamboat Springs and in December 1996 it was announced that the proposed largest geothermal district heating system in the U.S. would supply an industrial park in the area. The active geothermal area is located within the north-south trending graben like trough between the Carson and Virginia Ranges at the southern end of Truckee Meadows. Hot springs and other geothermal features occur over an area of about one square mile. The mid-basin location is controlled by faulting more or less parallel to the major mountain-front faults. It is believed that the heat source for the system is a cooling magmatic body at depth. The Steamboat geothermal area consists of a deep, high-temperature (215{degrees}C to 240{degrees} C) geothermal system, a shallower, moderate-temperature (160{degrees}C to 18{degrees} C) system, and a number of shallow low-temperature (30{degrees}C to 80{degrees}C) subsystems. The higher temperature systems are used for electric-power generation. It is proposed that the exit fluids from the electric power plants be used for the geothermal district heating system.

  12. Operational Planning of Low-Energy District Heating Systems Connected to Existing Buildings

    DEFF Research Database (Denmark)

    Tol, Hakan; Svendsen, Svend

    2012-01-01

    -energy houses in a traditional DH network, the aim in this paper was given to reduce the dimensions of the low-energy DH network as much as possible. Hence, the performance analyses of the inhouse radiator heating systems equipped in existing buildings were carried out for low temperatures of supply and return......This article focuses on low-energy District Heating (DH) systems operating in low-temperatures such as 55°C in terms of supply and 25°C in terms of return in connection with existing buildings. Since the heat loss from the network has a significant impact in case of supplying heat to low....... The response of the radiator heating systems at different levels of supply temperature was used to form the operational planning of the low-energy DH system, which determined the design parameters of the low-energy DH network in terms of overall mass flow requirement and the return temperature from...

  13. Power supply system design and build for Antarctica telescope

    Science.gov (United States)

    Du, Fujia; Li, Hao; Li, Aiai

    2016-07-01

    Currently, more and more telescopes were built and installed in Dome A of Antarctic. The telescopes are remote controlled, unattended operation due to Dome A's environment. These telescopes must be work successfully at least one year without any failure. According to past experience, the power supply system is the weakest point in whole system. The telescopes have to stop if the power system have a problem, even a minor problem. So the high requirement for power supply system are presented. The requirement include high reliability, the self-diagnosis and perfect monitor system. Furthermore, the optic telescope only can work at night. The power source mainly relay on diesel engine. To protect the Antarctic environment and increase the life of engines. The power capacity is limited during observation. So it need the power supply system must be high power factor, high efficient. To meet these requirement, one power supply system was design and built for Antarctic telescope. The power supply system have the following features. First, we give priority to achieve high reliability. The reliability of power system was calculated and the redundant system is designed to make sure that the spare one can be work immediately when some parts have problems. Second, the perfect monitor system was designed to monitor the voltage, current, power and power factor for each power channel. The status of power supply system can be acquired by internet continuously. All the status will be logged in main computer for future analysis. Third, the PFC (Power Factor Correction) technology was used in power supply system. This technology can dramatically increase the power factor, especially in high power situation. The DC-DC inverter instead of AC-DC inverter was used for different voltage level to increase the efficient of power supply.

  14. The Complex Economic System of Supply Chain Financing

    Science.gov (United States)

    Zhang, Lili; Yan, Guangle

    Supply Chain Financing (SCF) refers to a series of innovative and complicated financial services based on supply chain. The SCF set-up is a complex system, where the supply chain management and Small and Medium Enterprises (SMEs) financing services interpenetrate systematically. This paper establishes the organization structure of SCF System, and presents two financing models respectively, with or without the participation of the third-party logistic provider (3PL). Using Information Economics and Game Theory, the interrelationship among diverse economic sectors is analyzed, and the economic mechanism of development and existent for SCF system is demonstrated. New thoughts and approaches to solve SMEs financing problem are given.

  15. Optimal Dispatching of Large-scale Water Supply System

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    This paper deals with the use of optimal control techniques in large-scale water distribution networks. According to the network characteristics and actual state of the water supply system in China, the implicit model, which may be solved by utilizing the hierarchical optimization method, is established. In special, based on the analyses of the water supply system containing variable-speed pumps, a software tool has been developed successfully. The application of this model to the city of Shenyang (China) is compared to experiential strategy. The results of this study show that the developed model is a very promising optimization method to control the large-scale water supply systems.

  16. Intelligent Vehicle Electrical Power Supply System with Central Coordinated Protection

    Institute of Scientific and Technical Information of China (English)

    YANG Diange; KONG Weiwei; LI Bing; LIAN Xiaomin

    2016-01-01

    The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect;electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle’s battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle’s power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.

  17. Intelligent vehicle electrical power supply system with central coordinated protection

    Science.gov (United States)

    Yang, Diange; Kong, Weiwei; Li, Bing; Lian, Xiaomin

    2016-07-01

    The current research of vehicle electrical power supply system mainly focuses on electric vehicles (EV) and hybrid electric vehicles (HEV). The vehicle electrical power supply system used in traditional fuel vehicles is rather simple and imperfect; electrical/electronic devices (EEDs) applied in vehicles are usually directly connected with the vehicle's battery. With increasing numbers of EEDs being applied in traditional fuel vehicles, vehicle electrical power supply systems should be optimized and improved so that they can work more safely and more effectively. In this paper, a new vehicle electrical power supply system for traditional fuel vehicles, which accounts for all electrical/electronic devices and complex work conditions, is proposed based on a smart electrical/electronic device (SEED) system. Working as an independent intelligent electrical power supply network, the proposed system is isolated from the electrical control module and communication network, and access to the vehicle system is made through a bus interface. This results in a clean controller power supply with no electromagnetic interference. A new practical battery state of charge (SoC) estimation method is also proposed to achieve more accurate SoC estimation for lead-acid batteries in traditional fuel vehicles so that the intelligent power system can monitor the status of the battery for an over-current state in each power channel. Optimized protection methods are also used to ensure power supply safety. Experiments and tests on a traditional fuel vehicle are performed, and the results reveal that the battery SoC is calculated quickly and sufficiently accurately for battery over-discharge protection. Over-current protection is achieved, and the entire vehicle's power utilization is optimized. For traditional fuel vehicles, the proposed vehicle electrical power supply system is comprehensive and has a unified system architecture, enhancing system reliability and security.

  18. KSTAR RF heating system development

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, J. G.; Kim, S. K.; Hwang, C. K. (and others)

    2007-10-15

    Design, high-voltage test, and installation of 6 MW ICRF heating system for KSTAR is completed. The antenna demonstrated satisfactory standoff at high voltages up to 41 kV for 300 sec. The result indicates good power handling capabilities of the antenna as high as 10 MW/m2. This power density is equivalent to RF power coupling of 6 MW into a 4 {omega}/m target plasma, and is typical of advanced tokamak heating scenarios. In addition, vacuum feed through, DC break, and liquid stub developed for 300 sec operation are installed, as well as a 2 MW, 30-60MHz transmitter. The transmitter successfully produced output powers of 600 kW continuously, 1.5{approx}1.8 MW for 300 sec, and 2 MW for 100 msec or shorter pulses. A realtime control system based on DSP and EPICS is developed, installed, and tested on the ICRF system. Initial results from feasibility study indicate that the present antenna and the transmission lines could allow load-resilient operation on KSTAR. Until the KSTAR tokamak start to produce plasmas in 2008, however, hands-on operational experiences are obtained from participating in ICRF heating experiments at ASDEX and DIII-D tokamaks arranged through international cooperation.

  19. Modeling sustainability in renewable energy supply chain systems

    Science.gov (United States)

    Xie, Fei

    This dissertation aims at modeling sustainability of renewable fuel supply chain systems against emerging challenges. In particular, the dissertation focuses on the biofuel supply chain system design, and manages to develop advanced modeling framework and corresponding solution methods in tackling challenges in sustaining biofuel supply chain systems. These challenges include: (1) to integrate "environmental thinking" into the long-term biofuel supply chain planning; (2) to adopt multimodal transportation to mitigate seasonality in biofuel supply chain operations; (3) to provide strategies in hedging against uncertainty from conversion technology; and (4) to develop methodologies in long-term sequential planning of the biofuel supply chain under uncertainties. All models are mixed integer programs, which also involves multi-objective programming method and two-stage/multistage stochastic programming methods. In particular for the long-term sequential planning under uncertainties, to reduce the computational challenges due to the exponential expansion of the scenario tree, I also developed efficient ND-Max method which is more efficient than CPLEX and Nested Decomposition method. Through result analysis of four independent studies, it is found that the proposed modeling frameworks can effectively improve the economic performance, enhance environmental benefits and reduce risks due to systems uncertainties for the biofuel supply chain systems.

  20. DEVELOPMENT OF MATHEMATICAL MODEL OF THE HEATING SYSTEM OF THE MULTI-STORIED HOUSE

    Directory of Open Access Journals (Sweden)

    Postolatii V.M.

    2009-08-01

    Full Text Available The mathematical model of a heating system of the multi-storied house is developed, allowing solving a problem of distribution between apartments of heat of the centralized heat supply. It is taken into account own independently developed heat, which is determinate by means of individual counters of gas and the electric power. Basic feature of model is the opportunity of the account of mutual heat exchange between apartments.

  1. Investigation of ammonia/water hybrid absorption/compression heat pumps for heat supply temperatures above 100 °C

    DEFF Research Database (Denmark)

    Jensen, Jonas Kjær; Reinholdt, Lars; Markussen, Wiebke Brix

    2014-01-01

    and the liquid circulation ratio both influence these constraints. The paper investigates feasible combinations of these parameters. A numerical HACHP model is developed in Engineering Equation Solver (EES). The constrained parameters are evaluated for a range of combinations for systems with supply temperatures...... pressures. Using standard refrigeration components (28 bar) HACHP up to 100 °C are commercially available. Components developed for high pressure NH3 (52 bar) and transcritical CO2 (140 bar) increase the limiting allowable pressures. It is therefore relevant to evaluate the feasible supply temperatures...

  2. Heat of fusion storage systems for combined solar systems in low energy buildings

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe; Furbo, Simon

    2004-01-01

    Solar heating systems for combined domestic hot water and space heating has a large potential especially in low energy houses where it is possible to take full advantage of low temperature heating systems. If a building integrated heating system is used – e.g. floor heating - the supply temperature...... (and the the return temperature) would only be a few degrees above room temperature due to the very low heating demand and the large heat transfer surface area. One of the objectives in a newly started IEA Task 32 project is to investigate and develop improved thermal storages for combined solar...... systems through further improvement of water based storages and in parallel to investigate the potential of using storage designs with phase change materials, PCM. The advantage of phase change materials is that large amounts of energy can be stored without temperature increase when the material is going...

  3. Effect of Climate Change on the Food Supply System: Implications ...

    African Journals Online (AJOL)

    Effect of Climate Change on the Food Supply System: Implications for Food ... results in global warming with its attendant consequences such as floods, drought, forest fires, poverty, malnutrition, health and various socioeconomic problems.

  4. Heat-pump-centered integrated community energy systems. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-01

    A Heat Pump Centered-Integrated Community Energy System (HP-ICES) concept was explored and developed that is based on use of privately owned ice-making heat pumps in each building or complex within a community. These heat pumps will provide all of the space heating, space cooling and domestic hot water needs. All of the community input energy required is provided by electrical power, thereby eliminating a community's dependence on gas or oil supplies. The heat pumps will operate in both air and water source modes, deriving performance advantages of both. The possible forms of an HP-ICES system, the technical and economic limitations, environmental impacts and other factors are discussed from a general viewpoint. The concept is applied to a specific planned community and its performance and economic features are examined in detail. It is concluded that the HP-ICES concept is technically viable, but that its economic desirability as compared with conventional heat pump systems is hampered by much higher initial costs, and that the economic feasibility of HP-ICES systems will depend on future fuel source costs and supply and on electric power rates. (LCL)

  5. Heat pumps in combined heat and power systems

    DEFF Research Database (Denmark)

    Ommen, Torben Schmidt; Markussen, Wiebke Brix; Elmegaard, Brian

    2014-01-01

    of the considered cases. When considering a case where the heat pump is located at a CHP (combined heat and power) plant, a configuration that increases the DH return temperature proposes the lowest operation cost, as low as 12 EUR MWh-1 for a 90 °C e 40 °C DH network. Considering the volumetric heating capacity......Heat pumps have previously been proposed as a way to integrate higher amounts of renewable energy in DH (district heating) networks by integrating, e.g., wind power. The paper identifies and compares five generic configurations of heat pumps in DH systems. The operational performance......, a third configuration is superior in all cases. Finally, the three most promising heat pump configurations are integrated in a modified PQ-diagram of the CHP plant. Each show individual advantages, and for two, also disadvantages in order to achieve flexible operation....

  6. WORKING PARK-FUEL CELL COMBINED HEAT AND POWER SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Allan Jones

    2003-09-01

    This report covers the aims and objectives of the project which was to design, install and operate a fuel cell combined heat and power (CHP) system in Woking Park, the first fuel cell CHP system in the United Kingdom. The report also covers the benefits that were expected to accrue from the work in an understanding of the full technology procurement process (including planning, design, installation, operation and maintenance), the economic and environmental performance in comparison with both conventional UK fuel supply and conventional CHP and the commercial viability of fuel cell CHP energy supply in the new deregulated energy markets.

  7. Current contributions on the technical thermodynamics, power engineering and district heating supply. Special publication; Aktuelle Beitraege zur technischen Thermodynamik, Energietechnik und Fernwaermeversorgung. Sonderveroeffentlichung

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-03-15

    Within the special publication under consideration, the German Heat and Power Association (Frankfurt (Main), Federal Republic of Germany) presents the following current contributions on the technical thermodynamics, power engineering and district heating supply: (1) Cellular metallic materials for innovative latent heat accumulator technologies (Jens Meinert); (2) Compressed air storage - technology, chances and problems (Rutger Kretschmer); (3) KWK electricity - Identification and evaluation (Matthias Krause); (4) Investigation of the storage ability of district heating grids and implementation into the optimized planning of heat generators (Sebastian Gross); (5) Autarcic thermal densification to the combined heat and power and cooling production? - A fundamental thermodynamic consideration (Torben Moeller); (6) Modelling of cogeneration power plants - Investigation of the transformation opportunity of existing district heating systems in LowEx grids (Martin Rhein); (7) Discrete building model for the dynamic thermohydraulic simulation of district heating (Dominik Haas); (8) Ventilation and degasification of solar power plants (Karin Ruehling); (9) Integral simulation of district heating with TRNSYS-TUD (Steffen Robbi); (10) Theoretical analyses of return temperatures in building heating networks (Andreas Meinzenbach); (11) Municipal energy efficiency as an important contribution to the reduction of greenhouse gas emissions (Matthias Mischke); (12) Investigation of the latent heat storage system PK 6 for use in air-conditioning installations (Sebastian Pinnau); (13) The role of the thermodynamics in the electromobility (Lars Schinke); (14) Flow and heat transfer in cooling channels with methane (Andre Schlott); (15) Numerical calculations of stoves fired with wooden logs (Ulf Senechal); (16) Supply of thermodynamic substance data for working fluids of power engineering (Hans-Joachim Kretzschmar); (17) Cyclic pipe-ground interaction in solar-thermal heat grids

  8. Residential CO2 Heat Pump System for Combined Space Heating and Hot Water Heating

    OpenAIRE

    Stene, Jørn

    2004-01-01

    Carbon dioxide (CO2, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO2 heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO2 heat pump systems for combined space heating and hot water hea...

  9. An Integrated Framework for Assessment of Hybrid Water Supply Systems

    Directory of Open Access Journals (Sweden)

    Mukta Sapkota

    2015-12-01

    Full Text Available Urban water managers around the world are adopting decentralized water supply systems, often in combination with centralized systems. While increasing demand for water arising from population growth is one of the primary reasons for this increased adoption of alternative technologies, factors such as climate change, increased frequency of extreme weather events and rapid urbanization also contribute to an increased rate of adoption of these technologies. This combination of centralized-decentralized water systems approach is referred to as “hybrid water supply systems” and is based on the premise that the provision of alternative water sources at local scales can both extend the capacity of existing centralized water supply infrastructures, and improve resilience to variable climatic conditions. It is important to understand, however, that decentralized water production and reuse may change the flow and composition of wastewater and stormwater, thereby potentially also having negative impacts on its effectiveness and performance. This paper describes a framework to assess the interactions between decentralized water supply systems and existing centralized water servicing approaches using several analytical tools, including water balance modelling, contaminant balance modelling and multi-criteria decision analysis. The framework enables the evaluation of impacts due to change in quantity and quality of wastewater and stormwater on the existing centralized system arising from the implementation of hybrid water supply systems. The framework consists of two parts: (1 Physical system analysis for various potential scenarios and (2 Ranking of Scenarios. This paper includes the demonstration of the first part of the framework for an area of Melbourne, Australia by comparing centralized water supply scenario with a combination of centralized water supply and reuse of treated waste water supply scenario.

  10. Influence of the ventilation system on thermal comfort of the chilled panel system in heating mode

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Zhe; Ding, Yan; Wang, Shuo; Yin, Xinglei; Wang, Menglei [Tianjin University, Tianjin 300072 (China)

    2010-12-15

    In heating mode, fresh air is still essential for a chilled panel system in order to ensure the indoor air quality. In this paper, a chilled ceiling panel system was designed and built in a typical office room. The thermal environment and thermal comfort in the room were fully measured and evaluated by using the Fanger's PMV-PPD model and the standard of ISO 7730 respectively, when room was heated in two modes, one of which is the chilled panel heating mode and the other of which is the combined heating mode of chilled panel and supply air. The research results indicate that in the combined mode, ceiling ventilation improves the general thermal comfort and reduces the risk of local discomfort. Under the condition of same general thermal comfort, the heating supply upper limit of chilled panel can be increased by 12.3% because of air mixing effect caused by introduction of air ventilation. (author)

  11. ENERGY SUPPLY OF COMMERCIAL GREENHOUSE WITH THE GAS DRIVEN HEAT PUMP

    Directory of Open Access Journals (Sweden)

    Sit M.L.

    2013-08-01

    Full Text Available Abstract: The aim of the work is to develop energy efficient schemes of industrial greenhouse designed for year-round production of plants that requires year-round maintenance of strongly prescribed temperature and humidity inside the greenhouse. The complex "gas driven “water-air” heat pump – electric generator" (for use during the heating season as well as the "gas driven heat pump “water-air” – electric generator – desiccant - evaporative chiller" which work in the off-season. The developed system produces heat and electricity (during the heating season as well as cold and electricity (the rest of the year. Comparative analyses of greenhouse cooling by water and air cooling systems have been performed. Proposed structures have a high efficiency as compared with conventional circuits (boiler - chiller.

  12. Adapting CHP Software to suit the modelling of heat pump and refrigeration systems

    NARCIS (Netherlands)

    Verschoor, M.J.E.

    1998-01-01

    The role of heat pumps and refrigeration machines as integrated parts of energy supply systems is increasing as a result of the search for systems which supply the desired amounts and types of energy in an energy-efficient manner. Tools to support engineers in designing, analysing and optimising suc

  13. Adapting CHP Software to suit the modelling of heat pump and refrigeration systems

    NARCIS (Netherlands)

    Verschoor, M.J.E.

    1998-01-01

    The role of heat pumps and refrigeration machines as integrated parts of energy supply systems is increasing as a result of the search for systems which supply the desired amounts and types of energy in an energy-efficient manner. Tools to support engineers in designing, analysing and optimising

  14. Perspectives for the Danish heat supply towards 2025. Technical background report to the Energy Strategy 2025; Perspektiver for den danske varmeforsyning frem mod 2025. Teknisk baggrundsrapport til Energistrategi 2025

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-06-01

    This report describes the economy within different heating systems today and in 2025. A number of focus areas are addressed: 1) joint supply in the future, 2) phasing out of oil for individual heating, and 3) the possibilities for limiting/making effective the power consumption for heating. Special attention is paid to single-family houses, in which a considerable part of the energy consumption for heating is used. Though the report doesn't provide a complete picture of the Danish heat supply, the calculations can form basis for an estimate of the probable trend for Danish heat supply towards 2025. This probable trend forms background for projections of the energy consumption of heating in dwellings, which enters into the joint projections, manufactured in connection with the Energy Strategy 2025. (BA)

  15. Optimizing the Heat Exchanger Network of a Steam Reforming System

    DEFF Research Database (Denmark)

    Nielsen, Mads Pagh; Korsgaard, Anders Risum; Kær, Søren Knudsen

    2004-01-01

    Proton Exchange Membrane (PEM) based combined heat and power production systems are highly integrated energy systems. They may include a hydrogen production system and fuel cell stacks along with post combustion units optionally coupled with gas turbines. The considered system is based on a natural...... steam reforming reaction and steam must be generated. The dependence of the temperature profiles on conversion in shift reactors for gas purification is also significant. The optimum heat integration in the system is thus imperative in order to minimize the need for hot and cold utilities. A rigorous 1D...... gas steam reformer along with gas purification reactors to generate clean hydrogen suited for a PEM stack. The temperatures in the various reactors in the fuel processing system vary from around 1000°C to the stack temperature at 80°C. Furthermore, external heating must be supplied to the endothermic...

  16. Control of supply temperature

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, H.; Nielsen, T.S.; Soegaard, H.T.

    1996-09-01

    For many district heating systems, e.g. the system in Hoeje Taastrup, it is desirable to minimize the supply temperature from the heat production unit(s). Lower supply temperature implies lower costs in connection with the production and distribution of heat. Factors having impact on the heat demand are for instance solar radiation, wind speed, wind direction and a climate independent part, which is a function of the time of the day/week/year. By applying an optimization strategy, which minimizes the supply temperature, it is assumed that optimal economical operation can be obtained by minimizing the supply temperature and thereby the heat losses in the system. The models and methods described in this report take such aspects into account, and can therefore be used as elements in a more efficient minimization of the supply temperature. The theoretical part of this report describes models and methods for optimal on-line control of the supply temperature in district heating systems. Some of the models and methods have been implemented - or are going to be implemented - in the computer program PRESS which is a tool for optimal control of supply temperature and forecasting of heat demand in district heating systems. The principles for using transfer function models are briefly described. The ordinary generalized predictive control (OGPC) method is reviewed, and several extensions of this method are suggested. New controller, which is called the extended generalized predictive controller (XGPC), is described. (EG) 57 refs.

  17. Investigation of thermochemical biorefinery sizing and environmental sustainability impacts for conventional supply system and distributed preprocessing supply system designs

    Energy Technology Data Exchange (ETDEWEB)

    Muth, jr., David J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Langholtz, Matthew H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Tan, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jacobson, Jacob [Idaho National Lab. (INL), Idaho Falls, ID (United States); Schwab, Amy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wu, May [Argonne National Lab. (ANL), Argonne, IL (United States); Argo, Andrew [Sundrop Fuels, Golden, CO (United States); Brandt, Craig C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Cafferty, Kara [Idaho National Lab. (INL), Idaho Falls, ID (United States); Chiu, Yi-Wen [Argonne National Lab. (ANL), Argonne, IL (United States); Dutta, Abhijit [National Renewable Energy Lab. (NREL), Golden, CO (United States); Eaton, Laurence M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Searcy, Erin [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-03-31

    The 2011 US Billion-Ton Update estimates that by 2030 there will be enough agricultural and forest resources to sustainably provide at least one billion dry tons of biomass annually, enough to displace approximately 30% of the country's current petroleum consumption. A portion of these resources are inaccessible at current cost targets with conventional feedstock supply systems because of their remoteness or low yields. Reliable analyses and projections of US biofuels production depend on assumptions about the supply system and biorefinery capacity, which, in turn, depend upon economic value, feedstock logistics, and sustainability. A cross-functional team has examined combinations of advances in feedstock supply systems and biorefinery capacities with rigorous design information, improved crop yield and agronomic practices, and improved estimates of sustainable biomass availability. A previous report on biochemical refinery capacity noted that under advanced feedstock logistic supply systems that include depots and pre-processing operations there are cost advantages that support larger biorefineries up to 10 000 DMT/day facilities compared to the smaller 2000 DMT/day facilities. This report focuses on analyzing conventional versus advanced depot biomass supply systems for a thermochemical conversion and refinery sizing based on woody biomass. The results of this analysis demonstrate that the economies of scale enabled by advanced logistics offsets much of the added logistics costs from additional depot processing and transportation, resulting in a small overall increase to the minimum ethanol selling price compared to the conventional logistic supply system. While the overall costs do increase slightly for the advanced logistic supply systems, the ability to mitigate moisture and ash in the system will improve the storage and conversion processes. In addition, being able to draw on feedstocks from further distances will decrease the risk of biomass supply to

  18. The imperative for stronger vaccine supply and logistics systems.

    Science.gov (United States)

    Zaffran, Michel; Vandelaer, Jos; Kristensen, Debra; Melgaard, Bjørn; Yadav, Prashant; Antwi-Agyei, K O; Lasher, Heidi

    2013-04-18

    With the introduction of new vaccines, developing countries are facing serious challenges in their vaccine supply and logistics systems. Storage capacity bottlenecks occur at national, regional, and district levels and system inefficiencies threaten vaccine access, availability, and quality. As countries adopt newer and more expensive vaccines and attempt to reach people at different ages and in new settings, their logistics systems must be strengthened and optimized. As a first step, national governments, donors, and international agencies have crafted a global vision for 2020 vaccine supply and logistics systems with detailed plans of action to achieve five priority objectives. Vaccine products and packaging are designed to meet the needs of developing countries. Immunization supply systems support efficient and effective vaccine delivery. The environmental impact of energy, materials, and processes used in immunization systems is minimized. Immunization information systems enable better and more timely decision-making. Competent and motivated personnel are empowered to handle immunization supply chain issues. Over the next decade, vaccine supply and logistics systems in nearly all developing countries will require significant investments of time and resources from global and national partners, donors, and governments. These investments are critical if we are to reach more people with current and newer vaccines. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Using Soft Systems Methodology to Address Supply Chain Management Problems

    Directory of Open Access Journals (Sweden)

    Gulender Gencoglu

    2002-05-01

    Full Text Available This paper reports an investigation of if, and how, Soft Systems Methodology (SSM might.be used to facilitate better management of industry supply chains. In two workshops involving supply chain managers from the Textile Clothing and Footwear (TCF industry and industry facilitators, ways in which SSM techniques might supplement existing Supply Chain Management (SCM workshop approaches have been explored. Specifically, the placement of SSM techniques within a workshop setting, reactions to the techniques, perceived reasons for using SSM, together with strengths and difficulties encountered, have been examined.

  20. An Optimal Method for Developing Global Supply Chain Management System

    Directory of Open Access Journals (Sweden)

    Hao-Chun Lu

    2013-01-01

    Full Text Available Owing to the transparency in supply chains, enhancing competitiveness of industries becomes a vital factor. Therefore, many developing countries look for a possible method to save costs. In this point of view, this study deals with the complicated liberalization policies in the global supply chain management system and proposes a mathematical model via the flow-control constraints, which are utilized to cope with the bonded warehouses for obtaining maximal profits. Numerical experiments illustrate that the proposed model can be effectively solved to obtain the optimal profits in the global supply chain environment.

  1. Assessment of the cogeneration biogas plant possibilities in the autonomous power supply system

    Directory of Open Access Journals (Sweden)

    Sumarokova Liudmila

    2017-01-01

    Full Text Available The use of biomass and wood waste for heat and power production is increasing from year to year. Waste wood is low carbon footprint, has low sulfur content and relates to renewable energy sources. The paper demonstrates the possibility of increasing the energy efficiency of power supply system of the Stepanovka settlement (Tomsk region by means of replacing diesel power plant (DPP by the biofuel gas piston CHP. The assessment was based on the possibility of the technical and economic comparison of power supply options in the settlement.

  2. Use of perforated acoustic panels as supply air diffusers in diffuse ceiling ventilation systems

    DEFF Research Database (Denmark)

    Iqbal, Ahsan; Kazemi, Seyed Hossein; Ardkapan, Siamak Rahimi

    manufacturing perforated acoustic panels for the last 13 years. The panels can be used not only in applications related to acoustics but also as low pressure drop supply air diffusers, particularly in diffuse ceiling ventilation systems. The present study verifies on a theoretically level the performance......Ventilation is needed for diluting and removing the contaminants, odour and excess heat from the building interior. It is important that the inhabitants perceive the ventilated spaces as comfortable. Therefore, the supply air should reach all parts of the occupied zones. Troldtekt has been...

  3. Use of perforated acoustic panels as supply air diffusers in diffuse ceiling ventilation systems

    DEFF Research Database (Denmark)

    Iqbal, Ahsan; Kazemi, Seyed Hossein; Ardkapan, Siamak Rahimi

    Ventilation is needed for diluting and removing the contaminants, odour and excess heat from the building interior. It is important that the inhabitants perceive the ventilated spaces as comfortable. Therefore, the supply air should reach all parts of the occupied zones. Troldtekt has been...... manufacturing perforated acoustic panels for the last 13 years. The panels can be used not only in applications related to acoustics but also as low pressure drop supply air diffusers, particularly in diffuse ceiling ventilation systems. The present study verifies on a theoretically level the performance...

  4. OPTIMUM HEAT STORAGE DESIGN FOR SDHW SYSTEMS

    DEFF Research Database (Denmark)

    Shah, Louise Jivan; Furbo, Simon

    1997-01-01

    Two simulation models have been used to analyse the heat storage design’s influence on the thermal performance of solar domestic hot water (SDHW) systems. One model is especially designed for traditional SDHW systems based on a heat storage design where the solar heat exchanger is a built-in spiral...... of the tank design’s influence on the thermal performance of the systems is possible. By means of the calculations design rules for the two heat storage types are proposed....

  5. Heating technologies for limiting biomass consumption in 100% renewable energy systems

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Lund, Henrik; Connolly, David

    2011-01-01

    district heating enables the use of combined heat and power production (CPH) and other renewable resources than biomass such as large-scale solar thermal, large-heat pumps, geothermal heat, industrial surplus heat etc. which is important for reducing the biomass consumption. Where the energy density......The utilisation of biomass poses large challenges in renewable energy systems and buildings account for a substantial part of the energy supply also in 100% renewable energy systems. The analyses of heating technologies show that district heating systems are especially important in limiting...... the dependence on biomass resources and to create cost effective systems. District heating systems are especially important in renewable energy systems with large amounts of fluctuating renewable energy sources as it enables fuel efficient and lower cost energy systems with thermal heat storages. And also...

  6. Integration of Building energy and energy supply simulations for low-energy district heating supply to energy-efficient buildings

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro

    2012-01-01

    of the human behaviour regarding the building and link the results to the simulation program for DH networks. The results show that human behaviour can lead to 50% higher heating demand and 60% higher peak loads than expected according to reference values in standardized calculation of energy demand....... The analysis also shows that the connection of low-energy buildings to DH networks is potentially a good solution in Denmark for reaching the climatic goals, but a high degree of connection must be reached, especially for detached houses, where most of the buildings in a typical community must be connected......The future will demand implementation of C02 neutral communities, the consequences being a far more complex design of the whole energy system, since the future energy infrastructures will be dynamic and climate responsive systems. Software able to work with such level of complexity is at present...

  7. Optimizing the Heat Exchanger Network of a Steam Reforming System

    DEFF Research Database (Denmark)

    Nielsen, Mads Pagh; Korsgaard, Anders Risum; Kær, Søren Knudsen

    2004-01-01

    gas steam reformer along with gas purification reactors to generate clean hydrogen suited for a PEM stack. The temperatures in the various reactors in the fuel processing system vary from around 1000°C to the stack temperature at 80°C. Furthermore, external heating must be supplied to the endothermic...... steam reforming reaction and steam must be generated. The dependence of the temperature profiles on conversion in shift reactors for gas purification is also significant. The optimum heat integration in the system is thus imperative in order to minimize the need for hot and cold utilities. A rigorous 1D...

  8. Down-Hole Heat Exchangers: Modelling of a Low-Enthalpy Geothermal System for District Heating

    Directory of Open Access Journals (Sweden)

    M. Carlini

    2012-01-01

    Full Text Available In order to face the growing energy demands, renewable energy sources can provide an alternative to fossil fuels. Thus, low-enthalpy geothermal plants may play a fundamental role in those areas—such as the Province of Viterbo—where shallow groundwater basins occur and conventional geothermal plants cannot be developed. This may lead to being fuelled by locally available sources. The aim of the present paper is to exploit the heat coming from a low-enthalpy geothermal system. The experimental plant consists in a down-hole heat exchanger for civil purposes and can supply thermal needs by district heating. An implementation in MATLAB environment is provided in order to develop a mathematical model. As a consequence, the amount of withdrawable heat can be successfully calculated.

  9. Algal Supply System Design - Harmonized Version

    Energy Technology Data Exchange (ETDEWEB)

    Jared Abodeely; Daniel Stevens; Allison Ray; Debor

    2013-03-01

    The objective of this design report is to provide an assessment of current technologies used for production, dewatering, and converting microalgae cultivated in open-pond systems to biofuel. The original draft design was created in 2011 and has subsequently been brought into agreement with the DOE harmonized model. The design report extends beyond this harmonized model to discuss some of the challenges with assessing algal production systems, including the ability to (1) quickly assess alternative algal production system designs, (2) assess spatial and temporal variability, and (3) perform large-scale assessments considering multiple scenarios for thousands of potential sites. The Algae Logistics Model (ALM) was developed to address each of these limitations of current modeling efforts to enable assessment of the economic feasibility of algal production systems across the United States. The (ALM) enables (1) dynamic assessments using spatiotemporal conditions, (2) exploration of algal production system design configurations, (3) investigation of algal production system operating assumptions, and (4) trade-off assessments with technology decisions and operating assumptions. The report discusses results from the ALM, which is used to assess the baseline design determined by harmonization efforts between U.S. DOE national laboratories. Productivity and resource assessment data is provided by coupling the ALM with the Biomass Assessment Tool developed at PNNL. This high-fidelity data is dynamically passed to the ALM and used to help better understand the impacts of spatial and temporal constraints on algal production systems by providing a cost for producing extracted algal lipids annually for each potential site.

  10. Method of Distinguishing Hydrologic Drought for Water Supply System

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    It is very common to design water supply system to adjust runoff. Thus it will not meet the practical needs if only the hydrologic drought in natural basin is studied. In practice the natural water balance and water deficits must be researched, i. e., the adjusting effects of the water supply system such as a reservoir should be considered, and the drought event be distinguished according to the special system. The problem of drought identification under adjusted runoff was investigated in this study. By considering water transfer during different periods, a method to distinguish hydrologic drought for the water supply system was developed, and a standard drought severity index SWDSI was proposed. The method has been applied in Pan Jiakou water supply system in China. From 1953 to 1997, a total of 14 hydrologic droughts were identified in the water supply system, among which there were 3 severe droughts, 6 moderate droughts and 5 light droughts. The results are in good agreement with the historic drought records.

  11. To Question оf Using Power Reserve оf Power-and-Heat Supply Turbine Plants

    Directory of Open Access Journals (Sweden)

    S. A. Kachan

    2008-01-01

    Full Text Available The paper considers possibilities and limitations of various methods for obtaining power re-serve at power-and-heat supply turbo-generator sets.Approximate values of specific heat rate and quantity of reserve power and rate of its obtaining for various turbine plants are given in the paper.

  12. Planning Mechanisms for Regional Electric Power Supply System Development

    Directory of Open Access Journals (Sweden)

    Evgeniy Anatolyevich Malyshev

    2015-12-01

    Full Text Available Key problems of the regional electric power supply systems are examined. These problems result from a lack of regulated interaction mechanisms for uniting the different entities’ resources aimed at the realization of investment activities. One of the main problems of the power supply industry is physical and moral aging of both generating and networking equipment. In the article, the necessity of management system formation to control the development of power sector has been proved. The deficiencies of the modern investment procedure in power companies are described. The absence of continuity between the regional and local strategic planning documents and investment planning of a power company has been found out. The possibility to develop a new mechanism for attracting investment has been proposed. The regulation of joint activities to implement the development program for the regional power supply industry has been proposed. The management system to develop the Russian power industry has been proposed. The comparative analysis of generating capacity development mechanisms has been carried out, such as capacity supply agreement (CSA, investment support mechanism (ISM, and long-term power market (LPM. The interaction procedure of the planning of the power supply infrastructure development has been described. The mechanism connecting the state sectoral and regional planning and corporate planning of power supply infrastructure development has been proposed. The regional aspects of industrial policy and its legislative support have been considered. To successfully implement the public-private-partnership (PPP projects, it is necessary to create the effective PPP model within the federal and regional legislation framework; to develop the financial model providing the recoverability of investments; to provide a mutually beneficial cooperation between executive bodies and private investors. The possibility to apply the PPP mechanism for regional

  13. Power supply system for traction batteries

    Energy Technology Data Exchange (ETDEWEB)

    Perkuhn, E. (DETA Akkumulatorenwerk G.m.b.H., Bad Lauterberg (Germany, F.R.))

    1977-12-01

    Battery life is usually shortest in combined systems. The author discusses the causes of battery wear; if the battery is serviced correctly, it is mainly the charging process which is responsible. This process is described and explained. Battery chargers are mentioned where charging voltage and charging current are best adapted to the battery requirements. These battery chargers are also switched off automatically.

  14. Carbon footprints of heating oil and LPG heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Eric P., E-mail: ejohnson@ecosite.co.uk

    2012-07-15

    For European homes without access to the natural gas grid, the main fuels-of-choice for heating are heating oil and LPG. How do the carbon footprints of these compare? Existing literature does not clearly answer this, so the current study was undertaken to fill this gap. Footprints were estimated in seven countries that are representative of the EU and constitute two-thirds of the EU-27 population: Belgium, France, Germany, Ireland, Italy, Poland and the UK. Novelties of the assessment were: systems were defined using the EcoBoiler model; well-to-tank data were updated according to most-recent research; and combustion emission factors were used that were derived from a survey conducted for this study. The key finding is that new residential heating systems fuelled by LPG are 20% lower carbon and 15% lower overall-environmental-impact than those fuelled by heating oil. An unexpected finding was that an LPG system's environmental impact is about the same as that of a bio heating oil system fuelled by 100% rapeseed methyl ester, Europe's predominant biofuel. Moreover, a 20/80 blend (by energy content) with conventional heating oil, a bio-heating-oil system generates a footprint about 15% higher than an LPG system's. The final finding is that fuel switching can pay off in carbon terms. If a new LPG heating system replaces an ageing oil-fired one for the final five years of its service life, the carbon footprint of the system's final five years is reduced by more than 50%.

  15. Analysis and Design: Accounting Information System in Purchasing and Supplying

    Directory of Open Access Journals (Sweden)

    Noerlina Noerlina

    2011-05-01

    Full Text Available The purpose of the research are the purchase and material supply process are the main process of the company and it will determine the operational company, so it needs an accounting information system to help them in the planning and taking the best decision. Research methods used are data and information collected which using the analysis and design method. This method needs to support the design of accounting information system in the company. The result are there’s still any weaknesses happened that will hamper the operational company.Index Terms - Analysis and Design, Accounting Information System, Purchasing, Supply.

  16. Ligncellulosic feedstock supply systems with intermodal and overseas transportation

    Energy Technology Data Exchange (ETDEWEB)

    Ric Hoefnagels; Kara Cafferty; Erin Searcy; Jacob J. Jacobson; Martin Junginger; Thijs Cornelissen; Andre Faaij

    2014-12-01

    With growing demand for biomass from industrial uses and international trade, the logistic operations required to economically move the biomass from the field or forest to the end users have become increasingly complex. In addition to economics, understanding energy and GHG emissions is required to design cost effective, sustainable logistic process operations; in order to improve international supply chains it is also important to understate their interdependencies and related uncertainties. This article presents an approach to assess lignocellulosic feedstock supply systems at the operational level. For this purpose, the Biomass Logistic Model (BLM) has been linked with the Geographic Information Systems based Biomass Intermodal Transportation model (BIT-UU) and extended with inter-continental transport routes. Case studies of herbaceous and woody biomass, produced in the U.S. Midwest and U.S. Southeast, respectively, and shipped to Europe for conversion to Fischer-Tropsch (FT) diesel are included to demonstrate how intermodal transportation and, in particular, overseas shipping integrates with the bioenergy supply chains. For the cases demonstrated, biomass can be supplied at 99 € Mg-1 to 117 € Mg-1 (dry) and converted to FT-diesel at 19 € GJ-1 to 24 € GJ-1 depending on the feedstock type and location, intermediate (chips or pellets) and size of the FT-diesel production plant. With the flexibility to change the design of supply chains as well as input variables, many alternative supply chain cases can be assessed.

  17. Experimental evaluation of a heat pump for the water-supply heating of a public swimming pool

    Science.gov (United States)

    López, R.; Vaca, M.; Terres, H.; Lizardi, A.; Morales, J.; Chávez, S.

    2017-01-01

    In this work the analysis of the thermodynamic behavior of heat pumps (HP) which supply the energy needed in the public pool at the Aquatic Center of Azcapotzalco was performed. There are 18 installed HP’s but only those needed to provide the energy required are alternately activated. The evaluation was conducted during May and June of 2015. We selected one of the HP to implement temperature and pressure gauges at the inlet and outlet of the compressor. The measurements were made every day at three times, 6:30, 13:00 and 18:00 hours. In a period of 24 hours, 1 000 L evaporated, there was no variation registered overnight, since the pool was covered with plastic to avoid loss of the fluid. The heat pump provided 150 kW to maintain the water temperature at the right level of operation, namely 28 °C. The coefficients of performance (COP) of the HP were 6.39 at 6:30, 7.42 at 13:00 and 7:32 at 18:00 hrs., values which are very close to the one provided by the manufacturer.

  18. The Convenience Benefits of the District Heating System over Individual Heating Systems in Korean Households

    Directory of Open Access Journals (Sweden)

    Hyo-Jin Kim

    2017-08-01

    Full Text Available Koreans usually prefer the district heating system (DHS to the individual heating system (IHS because DHS can give them convenience and safety within their living environment. The Korean government thus plans to expand the DHS and requires information about the value that consumers place on the DHS over the IHS, which has not been dealt with in academic literature. This paper attempts to investigate Korean households’ willingness to pay (WTP for DHS over IHS, for residential heat (RH. To this end, the authors apply the dichotomous choice contingent valuation to assessing additional WTP for DHS using a survey of 1000 randomly selected households living in buildings with IHS. A mixture model is applied to deal with the zero WTP responses. The WTP distribution is specified as a mixture of two distributions, one with a point mass at zero and the other with full support on the positive half of the real line. The results show that the mean additional WTP for DHS-based RH over IHS-based RH is estimated to be KRW 5775 (USD 5.4 per Gcal. This value can be interpreted as the consumer’s convenience benefits of DHS over IHS, and amounts to approximately 6.0% of the average price: KRW 96,510 (USD 90.4 per Gcal in 2013, for IHS-based RH. This information is useful for evaluating changes to the method used for supplying RH from IHS to DHS.

  19. Device with Complex System for Heat Utilization and Reduction of Hazardous Air Emissions

    Directory of Open Access Journals (Sweden)

    O. Kascheeva

    2012-01-01

    Full Text Available Investigations concern heat utilization and reduction of hazardous emissions occurring in residential buildings and accompanying operation of a great number of industrial enterprises in particular heat and power objects, and firstly, heat-generating units of small power located in densely populated residential areas without centralized heat supply.The investigation target is to reduce cost of heat produced by independent system of building heat supply, reduction of air pollution  due to hazardous gas emissions and reduction of heat pollution of the environment as a result of building ventilation system operation, ventilation of their internal and external sewerage network and higher reliability of their operation.The target is achieved because the device with complex system for heat utilization and reduction of hazardous air emissions has additionally an assembly tank for mixing flue gases, ventilation emissions and atmospheric air, heat pump. Evaporation zone of the pump is a condensator of the gas mixture and its condensate zone contains a heat supply line for a heat consumer. The line is equipped with assembling  and distributing collectors, pipeline connecting the heat supply line with the system of direct and return delivery water from a boiler house, a separator for division of liquid and gaseous mixture phases, neutralizing devices for separate reduction of concentrations of hazardous and odorous substances being released in gaseous and liquid portions of the mixture, a pipeline for periodic supply of air with higher concentration of hazardous and odorous substances in the boiler furnace. The supplied air is obtained as a result of its passing through gas filters at their regeneration when their exchange capacity is exhausted.

  20. Optimal Control and Optimization of Stochastic Supply Chain Systems

    CERN Document Server

    Song, Dong-Ping

    2013-01-01

    Optimal Control and Optimization of Stochastic Supply Chain Systems examines its subject in the context of the presence of a variety of uncertainties. Numerous examples with intuitive illustrations and tables are provided, to demonstrate the structural characteristics of the optimal control policies in various stochastic supply chains and to show how to make use of these characteristics to construct easy-to-operate sub-optimal policies.                 In Part I, a general introduction to stochastic supply chain systems is provided. Analytical models for various stochastic supply chain systems are formulated and analysed in Part II. In Part III the structural knowledge of the optimal control policies obtained in Part II is utilized to construct easy-to-operate sub-optimal control policies for various stochastic supply chain systems accordingly. Finally, Part IV discusses the optimisation of threshold-type control policies and their robustness. A key feature of the book is its tying together of ...

  1. Monitoring water supply systems for anomaly detection and response

    NARCIS (Netherlands)

    Bakker, M.; Lapikas, T.; Tangena, B.H.; Vreeburg, J.H.G.

    2012-01-01

    Water supply systems are vulnerable to damage caused by unintended or intended human actions, or due to aging of the system. In order to minimize the damages and the inconvenience for the customers, a software tool was developed to detect anomalies at an early stage, and to support the responsible s

  2. The changing logistical system of the building materials supply chain

    NARCIS (Netherlands)

    Voordijk, Johannes T.

    2000-01-01

    This study analyses how policy measures and technological developments affect the trade-offs between elements of the logistical system of a supply chain. It is assumed that this logistical system consists of the following elements: sourcing, production, inventory, transportation and service. Two

  3. SYNTHESIS OF MODULAR UNINTERRUPTED POWER SUPPLY SYSTEMS WITH INCREASED RELIABILITY

    Directory of Open Access Journals (Sweden)

    Grigorash O. V.

    2015-04-01

    Full Text Available The level of technical development today requires the creation of highly effective, including reliable, uninter-rupted power supply systems. We have shown modern requirements and design features of modern systems of uninterruptible power supply, which should be built on a modular principle. It is shown that the problem of synthesis of systems in a modular approach is addressing three issues: development of the structure of the system subject to the requirements of consumers to quality of power and the allowable time of power outage; determining the required level redundancy of major functional units (blocks, elements to ensure the required reliability of the system; - ensuring the most effective interconnection of modules, including electromagnetic compatibility, and the rational use during normal and emergency operation of the system. We have proposed new structural solution of the main functional units and uninterrupted power supply systems in modular design. To reduce EMI and improve efficiency uninterruptible power supply systems in the design of static converters we need to use a transformer with a rotating magnetic field. In addition, the prospective current is to be used as a source of renewable energy. Another promising approach is the use of direct frequency converters as voltage stabilizers and frequency of the current

  4. Energy analysis of heat surplus storage systems in plastic tunnels

    Energy Technology Data Exchange (ETDEWEB)

    Kurpaska, S.; Latala, H. [Institute of Agricultural Engineering and Computer Science, University of Agriculture in Krakow, Balicka 116 B, Krakow 30-149 (Poland)

    2010-12-15

    This paper presents the findings of a theoretical analysis and experimental verification on the storing of heat excess in soil and liquid accumulators located in a foil tunnel. There was positive verification of the formulated macroscopic heat exchange model in both accumulators (maximum error 81%) and the quantity of heat stored in them was defined. During the experiments, under existing weather conditions, the amount of stored heat stood between 6 MJ and 45 MJ in the liquid accumulator and between 9 MJ and 130 MJ in the soil accumulator. The quantity of heat supplied from the accumulator to the interior of the tunnel during discharging, which stood between 0.6 MJ and 46 MJ, was also described. The COP was determined for the tested system both for the accumulator charging process and the discharging of the soil accumulator. Furthermore, the quantity of heat used for heating up heat originating from the discharging of the accumulator whilst heating the tunnel for favourable and unfavourable surrounding climate conditions was determined. (author)

  5. Technical and economical analysis of heat recovery in building ventilation systems

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.M. [Padova Univ. (Italy). Istituto di Ingegneria Gestionale; Gasparella, A. [Padova Univ. (Italy). Dottorato di Ricerca in Energetica

    1998-01-01

    Heat recovery in ventilation systems can be obtained from both the sensible fraction and the latent fraction. The possible sensible and total heat recovery depends on the climate and on the operating period. Total heat recovery is limited in winter by the humidity of the supply air; this lowers the exchange capacity in the heating period. Three different climates are considered (Milan, Rome, Palermo), evaluating the recovery for unitary air ventilation flow rate and the economic savings, also taking into account the reduction in the heating or cooling capacity. Heat recovery in a ventilating system must always be evaluated, since the investment is often profitable. (author)

  6. Bimode uninterruptible power supply compatibility in renewable hybrid energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Bower, W. (Sandia National Labs., Albuquerque, NM (USA)); O' Sullivan, G. (Abacus Controls, Inc., Somerville, NJ (USA))

    1990-08-01

    Inverters installed in renewable hybrid energy systems are typically used in a stand-alone mode to supply ac power to loads from battery storage when the engine-generator is not being used. Similarities in topology and in the performance requirements of the standby uninterruptible power supply (UPS) system and the hybrid system suggest the UPS could be used in hybrid energy systems. Another alternative to inverters with add-on charging circuits or standby UPS hardware is the Bimode UPS. The bimode UPS uses common circuitry and power components for dc to ac inversion and battery charging. It also provides an automatic and nearly instantaneous ac power transfer function when the engine-generator is started or stopped. The measured operating and transfer characteristics of a bimode UPS in a utility system and in a hybrid system are presented. The applicability of the bimode UPS to hybrid systems and its compatibility in a PV/engine-generator hybrid system are given.

  7. Solar heating system installed at Stamford, Connecticut

    Science.gov (United States)

    1979-01-01

    The solar heating system installed at the Lutz-Sotire Partnership Executive East Office Building, Stamford, Connecticut is described. The Executive East Office Building is of moderate size with 25,000 sq ft of heated space in 2 1/2 stories. The solar system was designed to provide approximately 50 percent of the heating requirements. The system components are described. Appended data includes: the system design acceptance test, the operation and maintenance manual, and as-built drawings and photographs.

  8. Flexibility of Supply Chain in Industrialised Building System (IBS

    Directory of Open Access Journals (Sweden)

    Kassim U.

    2014-01-01

    Full Text Available It is irrefutable that the construction industry is in need of a highly technological construction method or system for the simple aim of giving it a push it deserves. In Malaysia this technologically enhanced method is known as the Indutrialised Building System (IBS. Concerted efforts have been made for the past decade by various responsible parties especially by the government. Therefore, the IBS ‘Road Map’ 2003–2010 was introduced and now continues with the IBS ‘road map’ 2011-2015. However, its performance is still at its infancy, which target is only at an initial stage. This study seeks to identify and analyse the factor of the IBS’ system’s supply chain flexibility as a factor on the success of the system itself. It has been a suspicion that there exists a condition and situation where the supply chain is too rigid and is not flexible in fulfilling the needs and demands of the IBS development in Malaysia. This inflexible situation has brought about a broad range of problems and has stood in the way of the development of the industrialised building system, despite it being introduced since 1964, or 49 years ago. Flexibility in the IBS supply chain is very important and is associated with other industries like transportation, manufacturing industry, and others. Up until now, we have yet to discover any special studies related to the flexibility in the IBS supply chain in this country. Responding to this challenge, this research is hoped to be able to provide sufficient feedback to the solution to the IBS supply chain flexibility issue. The researcher is confident that the poor system flow of supply chain has impeded the advancement of the Industrialised Building System that has long been open to debate.

  9. Smart Power Supply for Battery-Powered Systems

    Science.gov (United States)

    Krasowski, Michael J.; Greer, Lawrence; Prokop, Norman F.; Flatico, Joseph M.

    2010-01-01

    A power supply for battery-powered systems has been designed with an embedded controller that is capable of monitoring and maintaining batteries, charging hardware, while maintaining output power. The power supply is primarily designed for rovers and other remote science and engineering vehicles, but it can be used in any battery alone, or battery and charging source applications. The supply can function autonomously, or can be connected to a host processor through a serial communications link. It can be programmed a priori or on the fly to return current and voltage readings to a host. It has two output power busses: a constant 24-V direct current nominal bus, and a programmable bus for output from approximately 24 up to approximately 50 V. The programmable bus voltage level, and its output power limit, can be changed on the fly as well. The power supply also offers options to reduce the programmable bus to 24 V when the set power limit is reached, limiting output power in the case of a system fault detected in the system. The smart power supply is based on an embedded 8051-type single-chip microcontroller. This choice was made in that a credible progression to flight (radiation hard, high reliability) can be assumed as many 8051 processors or gate arrays capable of accepting 8051-type core presently exist and will continue to do so for some time. To solve the problem of centralized control, this innovation moves an embedded microcontroller to the power supply and assigns it the task of overseeing the operation and charging of the power supply assets. This embedded processor is connected to the application central processor via a serial data link such that the central processor can request updates of various parameters within the supply, such as battery current, bus voltage, remaining power in battery estimations, etc. This supply has a direct connection to the battery bus for common (quiescent) power application. Because components from multiple vendors may have

  10. 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

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

    NARCIS (Netherlands)

    Leeuwen, van Richard P.; Fink, Jiří; Wit, de Jan B.; Smit, Gerard J.M.

    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 h

  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 h

  13. Design of the klystron filament power supply control system for EAST LHCD

    Science.gov (United States)

    Wu, Zege; Wang, Mao; Hu, Huaichuan; Ma, Wendong; Zhou, Taian; Zhou, Faxin; Liu, Fukun; Shan, Jiafang

    2016-09-01

    A filament is a critical component of the klystron used to heat the cathode. There are totally 44 klystrons in experimental advanced superconducting tokamak (EAST) lower hybrid current drive (LHCD) systems. All klystron filaments are powered by AC power suppliers through isolated transformers. In order to achieve better klystron preheat, a klystron filament power supply control system is designed to obtain the automatic control of all filament power suppliers. Klystron filament current is measured by PLC and the interlock between filament current and klystron high voltage system is also implemented. This design has already been deployed in two LHCD systems and proves feasible completely.

  14. Design of the klystron filament power supply control system for EAST LHCD

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Zege; Wang, Mao; Hu, Huaichuan; Ma, Wendong; Zhou, Taian; Zhou, Faxin; Liu, Fukun; Shan, Jiafang [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2016-09-15

    A filament is a critical component of the klystron used to heat the cathode. There are totally 44 klystrons in experimental advanced superconducting tokamak (EAST) lower hybrid current drive (LHCD) systems. All klystron filaments are powered by AC power suppliers through isolated transformers. In order to achieve better klystron preheat, a klystron filament power supply control system is designed to obtain the automatic control of all filament power suppliers. Klystron filament current is measured by PLC and the interlock between filament current and klystron high voltage system is also implemented. This design has already been deployed in two LHCD systems and proves feasible completely.

  15. Combined Heat and Power Dispatch Considering Heat Storage of Both Buildings and Pipelines in District Heating System for Wind Power Integration

    Directory of Open Access Journals (Sweden)

    Ping Li

    2017-06-01

    Full Text Available The strong coupling between electric power and heat supply highly restricts the electric power generation range of combined heat and power (CHP units during heating seasons. This makes the system operational flexibility very low, which leads to heavy wind power curtailment, especially in the region with a high percentage of CHP units and abundant wind power energy such as northeastern China. The heat storage capacity of pipelines and buildings of the district heating system (DHS, which already exist in the urban infrastructures, can be exploited to realize the power and heat decoupling without any additional investment. We formulate a combined heat and power dispatch model considering both the pipelines’ dynamic thermal performance (PDTP and the buildings’ thermal inertia (BTI, abbreviated as the CPB-CHPD model, emphasizing the coordinating operation between the electric power and district heating systems to break the strong coupling without impacting end users’ heat supply quality. Simulation results demonstrate that the proposed CPB-CHPD model has much better synergic benefits than the model considering only PDTP or BTI on wind power integration and total operation cost savings.

  16. Waste Heat Recapture from Supermarket Refrigeration Systems

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, Brian A [ORNL

    2011-11-01

    The objective of this project was to determine the potential energy savings associated with improved utilization of waste heat from supermarket refrigeration systems. Existing and advanced strategies for waste heat recovery in supermarkets were analyzed, including options from advanced sources such as combined heat and power (CHP), micro-turbines and fuel cells.

  17. HEAT PUMP STATION WITH CARBON DIOXIDE AS A WORKING FLUID ENERGY EFFICIENCY GROWTH IN COMBINED DISTRICT HEATING SYSTEM DUE TO ITS CONTROL SYSTEM OPTIMIZATION

    Directory of Open Access Journals (Sweden)

    Sit B.M.

    2008-04-01

    Full Text Available A diagram of the heat pump station (HPS for the central heat supply station of the district heating system, which gets the power from the CHP plant is examined. A block diagram of the control of the system and compressor pressure control system are examined. The description of the control laws of evaporator at the variable heat load of the HPS and control laws of the gas cooler taking into account the goal of achieving the maximum of COP of HPS is shown as well.

  18. Application of an industrial gas supply system to a hydrogen water chemistry installation

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, D.; Kuberka, K.A.

    1988-01-01

    Equipment for a hydrogen gas supply and an oxygen gas supply was adapted to meet operating safety criteria for a hydrogen water chemistry (HWC) application at a boiling water reactor (BWR) plant. The oxygen and hydrogen gases are supplied by vaporizing cryogenic liquid drawn from storage tanks. Cryogenic storage tanks consist of an inner vessel supported within an outer vessel, with insulation in the space between vessels. The supports and product lines on the inner container are small and flexible for heat transfer and thermal flexibility considerations. Cryogenic storage tank systems inherently have low natural frequencies and must be analyzed for dynamic response to site seismic criteria. Equipment modifications to meet application criteria were made without compromising performance. The guidelines for HWC installations were supplemented by a comprehensive design safety review to assess the equipment safeguards required to control potential product releases.

  19. Residential CO{sub 2} heat pump system for combined space heating and hot water heating

    Energy Technology Data Exchange (ETDEWEB)

    Stene, Joern

    2004-02-01

    Carbon dioxide (CO{sub 2}, R-744) has been identified as a promising alternative to conventional working fluids in a number of applications due to its favourable environmental and thermophysical properties. Previous work on residential CO{sub 2} heat pumps has been dealing with systems for either space heating or hot water heating, and it was therefore considered interesting to carry out a theoretical and experimental study of residential CO{sub 2} heat pump systems for combined space heating and hot water heating - o-called integrated CO{sub 2} heat pump systems. The scope of this thesis is limited to brine-to-water and water-to-water heat pumps connected to low-temperature hydronic space heating systems. The main conclusions are: (1) Under certain conditions residential CO{sub 2} heat pump systems for combined space heating and hot water heating may achieve the same or higher seasonal performance factor (SPF) than the most energy efficient state-of-the-art brine-to-water heat pumps. (2) In contrary to conventional heat pump systems for combined space heating and DHW heating, the integrated CO{sub 2} heat pump system achieves the highest COP in the combined heating mode and the DHW heating mode, and the lowest COP in the space heating mode. Hence, the larger the annual DHW heating demand, the higher the SPF of the integrated CO{sub 2} heat pump system. (3) The lower the return temperature in the space heating system and the lower the DHW storage temperature, the higher the COP of the integrated CO{sub 2} heat pump. A low return temperature in the space heating system also results in a moderate DHW heating capacity ratio, which means that a relatively large part of the annual space heating demand can be covered by operation in the combined heating mode, where the COP is considerably higher than in the space heating mode. (4) During operation in the combined heating mode and the DHW heating mode, the COP of the integrated CO{sub 2} heat pump is heavily influenced by

  20. The Design of the Parallel Switching Power Supply System

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2013-10-01

    Full Text Available This study introduces a parallel switching power supply system which is controlled by C8051F020 MCU. The system consists of DC/DC converter, voltage-controlled constant current source circuit, over-current protection circuit and auxiliary power supply. TPS54331 is used to constitute a highly efficient DC/DC converter, reducing the input DC voltage to supply the voltage-controlled constant current source circuit. The parallel current-sharing of the system is realized by the voltage-controlled constant current source circuit. The output current of the two parallel power supply can be adjusted by changing the control voltage. When the output current exceeds the set value, the system starts over-current protection circuit to cut off the power and delays to restore power automatically after a certain period of time. The test results show that the system is stable and reliable, easy to control and has a function of over-current protection and automatic recovery.

  1. Charging System of ECRH High-Voltage Power Supply and its Control System

    Institute of Scientific and Technical Information of China (English)

    胡国富; 丁同海; 刘保华; 姜书方

    2003-01-01

    High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating(ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) en-ergy of HVPS is stored in the capacitor banks, and they can power one or two gyrotrons. All theoperation of the charging system will be done by the control system, where the field signals areinterfaced to programmable logic controller (PLC). The use of PLC not only simplifies the controlsystem, but also enhances the reliability. The software written by using configuration softwareinstalled in the master computer allows for remote and multiple operator control, and the statusand data information is also remotely available.

  2. Thermal efficiency improvements : a chemical heat pump system application

    Energy Technology Data Exchange (ETDEWEB)

    Mert, M.S.; Salt, I.; Bolat, E. [Yildiz Technical Univ., Istanbul (Turkey). Dept. of Chemical Engineering; Karaca, F. [Marmara Univ., Istanbul (Turkey). Dept. of Chemical Engineering

    2006-07-01

    Chemical heat pumps are used to upgrade thermal energy and provide energy storage without losses. The feasibility of an n-hexane/1-hexane/hydrogen chemical heat pump system based on the dehydrogenation of n-hexane at low temperatures and 1-hexane at high temperatures was investigated. Theoretical analysis was carried out using related thermodynamic and equilibrium data to determine the thermal efficiency of the cycle. The latent heats of vaporization at normal boiling points for n-hexane and 1-hexane were calculated using a Riedel equation. Heat capacities as a function of temperature were calculated by Missenard group contribution and Rowlinson-Bondi methods. Estimated C{sub PL} values were presented. The effect of temperature on the Standart heat of reaction was calculated. Gibbs free energy was expressed as a function of temperature. Results indicated that a high 1-hexane concentration in the liquid mixture was required. The ratio of upgraded heat to supplied heat was the key parameter for estimating the thermal coefficient of performance (COP). It was observed that the efficiency of the pump increased with an increase in low level hydrogenation pressure. It was concluded that designing a chemical heat pump involves the consideration of a variety of interacting parameters. 17 refs., 5 tabs., 3 figs.

  3. LPV Identification of a Heat Distribution System

    DEFF Research Database (Denmark)

    Trangbæk, K; Bendtsen, Jan Dimon

    2010-01-01

    This paper deals with incremental system identification of district heating systems to improve control performance. As long as various parameters, e.g. valve settings, are kept fixed, the dynamics of district heating systems can be approximated well by linear models; however, the dynamics change ...

  4. Installation package for a solar heating system

    Science.gov (United States)

    1978-01-01

    Installation information is given for a solar heating system installed in Concho Indian School at El Reno, Oklahoma. This package includes a system Operation and Maintenance Manual, hardware brochures, schematics, system operating modes and drawings.

  5. Prototype solar-heating system design package

    Science.gov (United States)

    1979-01-01

    Design package for complete residential solar-heating system is given. Includes documents and drawings describing performance design, verification standards, and analysis of system with sufficient information to assemble working system.

  6. Prototype solar-heating system design package

    Science.gov (United States)

    1979-01-01

    Design package for complete residential solar-heating system is given. Includes documents and drawings describing performance design, verification standards, and analysis of system with sufficient information to assemble working system.

  7. Advances in Solar Heating and Cooling Systems

    Science.gov (United States)

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  8. Securing innovation through a differentiated supply system : The fashion industry

    NARCIS (Netherlands)

    Kamann, Dirk-Jan F.; Steller, Daan; Kaminishi, K; Duysters, G

    2007-01-01

    This paper describes a Situation where next to very innovative goods with short life cycles and volatile demand, rather commodity type goods are carried with more stable demand. A 'Two Lane Strategy' is described, with two different configurations of actors in the company's supply system. In each of

  9. Physical distribution costs in construction supply chains: a systems approach

    NARCIS (Netherlands)

    Voordijk, Johannes T.

    2010-01-01

    The objective of this study is to provide insights into the trade-offs of physical distribution cost patterns in construction supply chains by modelling and measuring these costs. The model of the physical distribution system consists of the following (cost) elements: inventory, transport, handling,

  10. Collaborative Learning in Advanced Supply Systems: The KLASS Pilot Project.

    Science.gov (United States)

    Rhodes, Ed; Carter, Ruth

    2003-01-01

    The Knowledge and Learning in Advanced Supply Systems (KLASS) project developed collaborative learning networks of suppliers in the British automotive and aerospace industries. Methods included face-to-face and distance learning, work toward National Vocational Qualifications, and diagnostic workshops for senior managers on improving quality,…

  11. Physical distribution costs in construction supply chains: a systems approach

    NARCIS (Netherlands)

    Voordijk, Hans

    2010-01-01

    The objective of this study is to provide insights into the trade-offs of physical distribution cost patterns in construction supply chains by modelling and measuring these costs. The model of the physical distribution system consists of the following (cost) elements: inventory, transport, handling,

  12. Advanced control of a water supply system: a case study

    NARCIS (Netherlands)

    Bakker, M.; Rajewicz, T.; Kien, H.; Vreeburg, J.H.G.; Rietveld, L.C.

    2014-01-01

    Conventional automatic production flow control and pump pressure control of water supply systems are robust and simple: production flow is controlled based on the level in the clear water reservoir and pump pressure is controlled on a static set-point. Recently, more advanced computer-based control

  13. Quantitative modelling in design and operation of food supply systems

    NARCIS (Netherlands)

    Beek, van P.

    2004-01-01

    During the last two decades food supply systems not only got interest of food technologists but also from the field of Operations Research and Management Science. Operations Research (OR) is concerned with quantitative modelling and can be used to get insight into the optimal configuration and opera

  14. Non standard pallet series designing problem in ammunition supply system

    Institute of Scientific and Technical Information of China (English)

    Li Liangchun; Guo Min; Wang Hongwei

    2005-01-01

    According to the compound packing problem in ammunition supply system in our army, the non-standard pallet series design model is proposed, and the original problem that can be solved as a set cover problem with a nested bin-packing problem, is analyzed, then two heuristic algorithms are applied to solve the problem.

  15. Water supply system decision making using multicriteria analysis

    African Journals Online (AJOL)

    2005-07-04

    Jul 4, 2005 ... managing urban water supply systems, for example, a shortage of resources available to ... which can be used according to the type of problem, such as choice-based, ranking- .... g(b) and g(a)), in other words, size of larger scale, where max corresponds to the ... ing that a dominance hypothesis is justified.

  16. Mitigating the Cost of Anarchy in Supply Chain Systems

    NARCIS (Netherlands)

    H.E. Romeijn (Edwin); W.J. van den Heuvel (Wim); J. Geunes (Joseph)

    2012-01-01

    textabstractIn a decentralized two-stage supply chain where a supplier serves a retailer who, in turn, serves end customers, operations decisions based on local incentives often lead to suboptimal system performance. Operating decisions based on local incentives may in such cases lead to a degree of

  17. Design of energy-efficient buildings using interaction between Building Simulation Programme and Energy Supply Simulations for District Heating

    DEFF Research Database (Denmark)

    Christensen, Jørgen Erik; Dalla Rosa, Alessandro; Nagla, Inese

    demand density for which the connection to low-energy district heating networks is cost-effective and energy efficient. By using a dynamic energy simulation program for buildings it is possible to analyze the influence of the human behaviour for the building and link the results to the simulation program...... for district heating networks. The results show that human behaviour can lead to 50% higher heating demand and 60% higher peak loads than expected according to reference values in standardized calculation of energy demand pattern in energy-efficient buildings. The consequence is that in order to get the full...... that there is a large potential for distributing energy in areas with energy efficient buildings. As a measure for the feasibility of district heating, the linear heat density can be used as a representative value, and the results show that it is possible to supply heat with low-energy district heating networks...

  18. A number of upgrades on RHIC power supply system

    Energy Technology Data Exchange (ETDEWEB)

    Mi, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Bruno, D. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Drozd, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Nolan, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Orsatti, F. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Heppener, G. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Di Lieto, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Schultheiss, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Samms, T. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Zapasek, R. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Sandberg, J. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2015-05-03

    This year marks the 15th run for the Relativistic Heavy Ion Collider (RHIC). Operation of a reliable superconducting magnet power supply system is a key factor of an accelerator’s performance. Over the past 15 years, the RHIC power supply group has made many improvements to increase the machine availability and reduce failures. During these past 15 years of operating RHIC a lot of problems have been solved or addressed. In this paper some of the essential upgrades/improvements are discussed.

  19. Improving Process Heating System Performance v3

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-04-11

    Improving Process Heating System Performance: A Sourcebook for Industry is a development of the U.S. Department of Energy (DOE) Advanced Manufacturing Office (AMO) and the Industrial Heating Equipment Association (IHEA). The AMO and IHEA undertook this project as part of an series of sourcebook publications developed by AMO on energy-consuming industrial systems, and opportunities to improve performance. Other topics in this series include compressed air systems, pumping systems, fan systems, steam systems, and motors and drives

  20. Book of abstracts: International Conference on Smart Energy Systems and 4th Generation District Heating

    DEFF Research Database (Denmark)

    It is a great pleasure to welcome you to the first International Conference on Smart Energy Systems and 4th Generation District Heating at Aalborg University, Copenhagen Campus on 25-26 August 2015. The conference is organised by the 4DH Strategic Research Centre in collaboration with Aalborg......-temperature district heating, the Strategic Research Centre for 4th Generation District Heating Technologies and Systems enhances the understanding of supply system design, infrastructure and heat savings. In future energy systems, combinations of low-temperature district heating resources and heat savings represent...... a promising alternative to individual heating solutions and passive or energy+ buildings. This change in the heating system also requires institutional and organisational changes that address the implementation of new technologies and enable new markets that can provide feasible solutions to society. We hope...

  1. Feedstock and Conversion Supply System Design and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jacobson, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Mohammad, R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Cafferty, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Kenney, K. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Searcy, E. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hansen, J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    The success of the earlier logistic pathway designs (Biochemical and Thermochemical) from a feedstock perspective was that it demonstrated that through proper equipment selection and best management practices, conventional supply systems (referred to in this report as “conventional designs,” or specifically the 2012 Conventional Design) can be successfully implemented to address dry matter loss, quality issues, and enable feedstock cost reductions that help to reduce feedstock risk of variable supply and quality and enable industry to commercialize biomass feedstock supply chains. The caveat of this success is that conventional designs depend on high density, low-cost biomass with no disruption from incremental weather. In this respect, the success of conventional designs is tied to specific, highly productive regions such as the southeastern U.S. which has traditionally supported numerous pulp and paper industries or the Midwest U.S for corn stover.

  2. Development of hybrid solar-assisted cooling/heating system

    KAUST Repository

    Huang, B.J.

    2010-08-01

    A solar-assisted ejector cooling/heating system (SACH) was developed in this study. The SACH combines a pump-less ejector cooling system (ECS) with an inverter-type heat pump (R22) and is able to provide a stable capacity for space cooling. The ECS is driven by solar heat and is used to cool the condenser of the R22 heat pump to increase its COP and reduce the energy consumption of the compressor by regulating the rotational speed of the compressor through a control system. In a complete SACH system test run at outdoor temperature 35 °C, indoor temperature 25 °C and compressor speed 20-80 Hz, and the ECS operating at generator temperature 90 °C and condensing temperature 37 °C, the corresponding condensing temperature of the heat pump in the SACH is 24.5-42 °C, cooling capacity 1.02-2.44 kW, input power 0.20-0.98 kW, and cooling COPc 5.11-2.50. This indicates that the use of ECS in SACH can effectively reduce the condensing temperature of the heat pump by 12.6-7.3 °C and reduce the power consumption by 81.2-34.5%. The SACH can also supply heat from the heat pump. At ambient temperature from 5 °C to 35 °C, the heating COPh is in the range 2.0-3.3. © 2010 Elsevier Ltd. All rights reserved.

  3. Radiant Heating and Cooling Systems. Part one

    DEFF Research Database (Denmark)

    Kim, Kwan Woo; Olesen, Bjarne W.

    2015-01-01

    The use of radiant heating systems has several thousand years of history.1,2 The early stage of radiant system application was for heating purposes, where hot air from flue gas (cooking, fires) was circulated under floors or in walls. After the introduction of plastic piping water-based radiant...... heating and cooling with pipes embedded in room surfaces (floor, wall, and ceiling), the application increased significantly worldwide. Earlier application of radiant heating systems was mainly for residential buildings because of its comfort and free use of floor space without any obstruction from...

  4. Approaches to optimization of core reactivity coefficirnts for the “MASTER” heat supply reactor

    Directory of Open Access Journals (Sweden)

    D.M. Titov

    2015-09-01

    Full Text Available After increasing the power output of heat supply reactor «MASTER» by insertion of the annular channel with coolant, feedback coefficients are deteriorated. Thereby, there was need to find ways for changing reactivity coefficients in new reactor design and at the same time to save natural circulation, low core pressure and outlet core temperature of coolant. Reactivity coefficients have been calculated depending on width and locations radius of annular coolant channel at once to fuel enrichment. Neutron-physical code WIMS-D4 was used as calculation tool. The results showed that the feedback coefficients optimum can be achieved by reducing of annular channel width and increasing of fuel enrichment. At the same time reactivity coefficients are insensitive to location of annular coolant channel radius changes. Restrictions for fuel enrichment (IAEA requirements coupled with geometry restrictions of annular channel listed above (impossible to remove the thermal power or significant increasing of heat exchangers height have shown that prospect of feedbacks improving via width and location of annular channel is used up. Possible improvements can be achieved by changing type of burnable poison and neutron spectrum.

  5. Solar heating and cooling of residential buildings: sizing, installation and operation of systems. 1980 edition

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-09-01

    This manual was prepared as a text for a training course on solar heating and cooling of residential buildings. The course and text are directed toward sizing, installation, operation, and maintenance of solar systems for space heating and hot water supply, and solar cooling is treated only briefly. (MHR)

  6. Geothermal district heating system feasibility analysis, Thermopolis, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    Goering, S.W.; Garing, K.L.; Coury, G.; Mickley, M.C.

    1982-04-26

    The purpose of this study is to determine the technical and economic feasibility of constructing and operating a district heating system to serve the residential, commercial, and public sectors in Thermopolis. The project geothermal resource assessment, based on reviews of existing information and data, indicated that substantial hot water resources likely exist in the Rose Dome region 10 miles northeast of Thermopolis, and with quantities capable of supporting the proposed geothermal uses. Preliminary engineering designs were developed to serve the space heating and hot water heating demands for buildings in the Thermopolis-East Thermopolis town service area. The heating district design is based on indirect geothermal heat supply and includes production wells, transmission lines, heat exchanger units, and the closed loop distribution and collection system necessary to serve the individual customers. Three options are presented for disposal of the cooled waters-reinjection, river disposal, and agricultural reuse. The preliminary engineering effort indicates the proposed system is technically feasible. The design is sized to serve 1545 residences, 190 businesses, and 24 public buildings. The peak design meets a demand of 128.2 million Btu at production rates of 6400 gpm.

  7. AUTOMATION OF THE RESIDENTIAL BUILDING WATER SUPPLY SYSTEM PUMPING STATION

    OpenAIRE

    A. M. Kulia

    2016-01-01

    Essence of process of water-supply of apartment dwelling house is considered. The existent state over of automation of the pumping stations is brought. The task of development of the effective system of automatic control is put by them. Possibility of decision of task is shown by the use in the system of frequency transformer that feeds the electrodrives of pumps, and also due to perfection of algorithms of the pumps rotation frequency adjusting and logical management of their switching a seq...

  8. Drought risk and vulnerability in water supply systems.

    OpenAIRE

    Garrote de Marcos, Luis; Cubillo, Francisco

    2008-01-01

    This paper provides an overview of the challenges presented to the managers of water supply systems by drought and water scarcity. Risk assessment is an essential tool for the diagnostic of water scarcity in this type of systems. The evaluation of the risk of water shortage is performed with the use of complex mathematical models. Different alternatives to address the problem are presented, covering a range of methodological approaches. The actions adopted to prevent or mitigate the effects o...

  9. Comparative analysis of the district heating systems of two towns in Croatia and Denmark

    DEFF Research Database (Denmark)

    Čulig-Tokić, Dario; Krajačić, Goran; Doračić, Borna

    2015-01-01

    This paper compares district heating systems in Zagreb and Aalborg in order to see their similarities and differences from which conclusions are drawn on how to improve the systems. The method chosen is the comparative analysis. Data is organized and structured so to allow clear and concise...... comparison. The results of the comparative analysis show that the district heating system in Aalborg is more advanced than the district heating system in Zagreb. This advantage is prominent in aspects of supply, demand, distribution and economic spheres. Some of the possible improvements include lowering...... specific heat and water losses. Systematic replacements and refurbishments of the old network pipes are key to this. Lowering the supply and return temperatures would enable better renewable energy sources integration. The integration of renewable energy sources in district heating systems is the most...

  10. Basics of Solar Heating & Hot Water Systems.

    Science.gov (United States)

    American Inst. of Architects, Washington, DC.

    In presenting the basics of solar heating and hot water systems, this publication is organized from the general to the specific. It begins by presenting functional and operational descriptions of solar heating and domestic hot water systems, outlining the basic concepts and terminology. This is followed by a description of solar energy utilization…

  11. Radiant Heating and Cooling Systems. Part two

    DEFF Research Database (Denmark)

    Kim, Kwan Woo; Olesen, Bjarne W.

    2015-01-01

    Control of the heating and cooling system needs to be able to maintain the indoor temperatures within the comfort range under the varying internal loads and external climates. To maintain a stable thermal environment, the control system needs to maintain the balance between the heat gain...

  12. Maximal Heat Generation in Nanoscale Systems

    Institute of Scientific and Technical Information of China (English)

    ZHOU Li-Ling; LI Shu-Shen; ZENG Zhao-Yang

    2009-01-01

    We investigate the heat generation in a nanoscale system coupled to normal leads and find that it is maximal when the average occupation of the electrons in the nanoscale system is 0.5,no matter what mechanism induces the heat generation.

  13. Rankine cycle waste heat recovery system

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Nelson, Christopher R.

    2015-09-22

    A waste heat recovery (WHR) system connects a working fluid to fluid passages formed in an engine block and/or a cylinder head of an internal combustion engine, forming an engine heat exchanger. The fluid passages are formed near high temperature areas of the engine, subjecting the working fluid to sufficient heat energy to vaporize the working fluid while the working fluid advantageously cools the engine block and/or cylinder head, improving fuel efficiency. The location of the engine heat exchanger downstream from an EGR boiler and upstream from an exhaust heat exchanger provides an optimal position of the engine heat exchanger with respect to the thermodynamic cycle of the WHR system, giving priority to cooling of EGR gas. The configuration of valves in the WHR system provides the ability to select a plurality of parallel flow paths for optimal operation.

  14. Simulation and assessment of agricultural biomass supply chain systems

    Directory of Open Access Journals (Sweden)

    D. Pavlou

    2017-05-01

    Full Text Available Agricultural biomass supply chain consists of a number of interacted sequential operations affected by various variables, such as weather conditions, machinery systems, and biomass features. These facts make the process of biomass supply chain as a complex system that requires computational tools, e.g. simulation and mathematical models, for their assessment and analysis. A biomass supply chain simulation model developed on the ExtendSim 8 simulation environment is presented in this paper. A number of sequential operations are applied in order biomass to be mowed, harvested, and transported to a biorefinery facility. Different operational scenarios regarding the travel distance between field and biorefinery facility, number of machines, and capacity of machines are analyzed showing how different parameters affect the processes within biomass supply chain in terms of time and cost. The results shown that parameters such as area of the field, travel distance, number of available machines, capacity of the machines, etc. should be taken into account in order a less time and/ or cost consuming machinery combination to be selected.

  15. Robust optimization methodologies for water supply systems design

    Directory of Open Access Journals (Sweden)

    J. Marques

    2012-08-01

    Full Text Available Water supply systems (WSSs are vital infrastructures for the well-being of people today. To achieve good customer satisfaction the water supply service must always be able to meet people's needs, in terms of both quantity and quality. But unpredictable extreme conditions can cause severe damage to WSSs and lead to poorer levels of service or even to their failure. Operators dealing with a system's day-to-day operation know that events like burst water mains can compromise the functioning of all or part of a system. To increase a system's reliability, therefore, designs should take into account operating conditions other than normal ones. Recent approaches based on robust optimization can be used to solve optimization problems which involve uncertainty and can find designs which are able to cope with a range of operating conditions. This paper presents a robust optimization model for the optimal design of water supply systems operating under different circumstances. The model presented here uses a hydraulic simulator linked to an optimizer based on a simulated annealing heuristic. The results show that robustness can be included in several ways for varying levels reliability and that it leads to more reliable designs for only small cost increases.

  16. Control challenges in domestic heating systems

    DEFF Research Database (Denmark)

    Thybo, Honglian; Larsen, Lars F. S.; Weitzmann, Peter

    2007-01-01

    The objective of this paper is to analyze domestic heating applications and identify unfavorable building constructions and control challenges to be addressed by high performance heating control systems. Heating of domestic houses use a large amount of the total energy consumption in Scandinavia....... Hence the potential of reducing energy consumption by applying high performance control is vast. Indoor climate issues are becoming more in focus, which also leads to a demand for high performance heating systems. The paper presents an analysis of how the building elements of today's domestic houses...

  17. Heats of adsorption for charcoal nitrogen systems

    Energy Technology Data Exchange (ETDEWEB)

    Prasad, M.; Akkimaradi, B.S.; Rastogi, S.C. [ISRO Satellite Centre, Bangalore (India). Thermal Systems Group; Rao, R.R. [Government College for Boys, Kolar, Karnataka (India); Srinivasan, K. [Indian Institute of Science, Bangalore (India). Dept. of Mechanical Engineering

    1999-07-01

    This paper develops an empirical equation for correlation of the loading dependence of the heat of adsorption for two samples of activated charcoal-nitrogen systems. Details are given of the use of isotherm data, the evaluation of the heat of adsorption using the Clausius-Clapeyron equation, the plotting of primary adsorption data, and the plotting of the heat of adsorption as a function of the loading of the two samples. The need to consider the heat of adsorption property when designing a system in which a gaseous medium is adsorbed by a solid sorbent is discussed. (UK)

  18. Performance analysis of hybrid district heating system

    DEFF Research Database (Denmark)

    Mikulandric, Robert; Krajačić, Goran; Khavin, Gennadii

    2013-01-01

    as problems related to transportation, storage and environmental impacts of biomass and waste utilisation. Implementation of heat storages in district heating systems could contribute to integration of intermittent energy sources. Hybridisation of heat production facility combines two or more different energy...... more extensively used in district heating systems either separately or as a supplement to traditional fossil fuels in order to achieve national energy policy objectives. However, they are still facing problems such as high intermittences, high energy production costs and low load factors as well...

  19. Analysis of crowbar action of high voltage DC power supply in the LHD ICRF system

    Energy Technology Data Exchange (ETDEWEB)

    Li Xiaodong [Southwestern Institute of Physics, Chengdu, Sichuan (China); Mutoh, T.; Kumazawa, R.; Watari, T.; Seki, T.; Shimpo, F.; Nomura, G.; Saito, K.

    1999-04-01

    Ion Cyclotron Range of Frequency (ICRF) heating will be applied to the Large Helical Device (LHD) at the 2nd experimental campaign in 1998. The LHD ICRF system is characterised by its high power (up to 12 MW at final stage) and steady state operation for more than 30 minutes. One of the main R and D items was a high power and steady state transmitter. The RF transmitter system having a wide frequency range from 25 to 95 MHz was designed and fabricated. This report describes the analysis of the DC power supply that contains the crowbar circuit protecting the tetrode from the arcing inside the tube. The DC power supply of the transmitter is fed from the commercial AC electric line which also supply the power to the LHD helical and poloidal coil power supplies. The voltage drop of the commercial line when the ICRF crowbar action happened is the serious problem for all experimental system. This paper analyses the crowbar effect on the commercial line with and without leakage transformer between the step-up transformer of transmitter and the commercial line. (author)

  20. Demonstrations of electric heating systems. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Haapakoski, M.; Laitila, R.; Ruska, T.

    1998-07-01

    In 1991, Imatran Voima launched the Demonstration Project of Electric Heating Systems. The project investigated in detail the energy consumption, housing comfort and electric power output rates of approximately one hundred electrically heated single-family houses and updated the investment cost information of heating systems. The project implemented and monitored quality electric heating concepts that guarantee a high standard of housing comfort. The targets in the project provided with combinations of floor, ceiling and window heating systems totalled 33. Furthermore, the project included 42 targets provided with water-circulated floor or radiator heating systems and 22 houses that had moved from oil or district heating systems into electric heating. The number of metering years received in the energy consumption measurements totalled 339. During the course of the project, six partial reports, one master's thesis and three summary reports were published. This is the final report of the project. It deals in brief with the major results. The best electric heating concept, in terms of housing comfort, is a floor heating system using cables supplemented by ceiling and window heating. Thanks to the heating units installed in the structures, the operative temperature grows by about one degree in comparison with a corresponding target heated with radiators. A typical, room-specifically-heated 140 m{sup 2} house consumes a total of 24,000 kWh of energy per year. Of this amount, electric space heating accounts for 11,500 kWh, heating with wood for 1,500 kWh, heating of tap water for 4,000 kWh and household electricity for 7,000 kWh. In a house provided with a water-circulated electric heating system the total energy consumption is, owing to the adjustment and storage losses, about 10 % higher. Of the energy consumption in the house, most part takes place during the period of nighttime electricity. The nighttime load in a 24-hour period with very low temperatures

  1. Solar heating system installed at Stamford, CT. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-09-01

    Information is provided on the solar heating system installed at the Lutz-Sotire Partnership Executive East Office Building, Stamford, Connecticut. The information consists of description of system and components, operation and maintenance manual, as-built drawings and manufacturer's component data. The solar system was designed to provide approximately 50 percent of the heating requirements. The solar facility has 2,561 sq. ft. of liquid flat plate collectors and a 6000 gallon, stone lined, well-insulated storage tank. Freeze protection is provided by a 50 percent glycol/water mixture in the collector loop. From the storage tank, solar heated water is fed into the building's distributed heat pump loop via a modulating three-way valve. If the storage tank temperature drops below 80/sup 0/F, the building loop may be supplied from the existing electrical hot water boilers. The Executive East Office Building is of moderate size, 25,000 sq. ft. of heated space in 2 1/2 stories. The solar system makes available for other users up to 150 KVA of existing electrical generating capacity.

  2. Defining regulatory requirements for water supply systems in Vietnam

    Directory of Open Access Journals (Sweden)

    Deryushev Leonid Georgiyevich

    2014-01-01

    Full Text Available In the article the authors offer their suggestions for improving the reliability of the standardization requirements for water supply facilities in Vietnam, as an analog of building regulations of Russia 31.13330.2012. In Russia and other advanced countries the reliability of the designed water supply systems is usual to assess quantitatively. Guidelines on the reliability assessment of water supply systems and facilities have been offered by many researchers, but these proposals are not officially approved. Some methods for assessing the reliability of water supply facilities are informally used in practice when describing their quality. These evaluation methods are simple and useful. However, the given estimations defy common sense and regulatory requirements used by all the organizations, ministries and departments, for example, of Russia, in the process of allowances for restoration and repair of water supply facilities. Inadequacy of the water supply facilities assessment is shown on the example of assessing the reliability of pipeline system. If we take MTBF of specific length of the pipeline as reliability index for a pipeline system, for example, 5 km, a pipeline of the similar gauge, material and working conditions with the length of 5 m, according to the estimation on the basis of non-official approach, must have a value of MTBF 1000 times greater than with the length of 5 km. This conclusion runs counter to common sense, for the reason that all the pipes in the area of 5 km are identical, have the same load and rate of wear (corrosion, fouling, deformation, etc.. It was theoretically and practically proved that products of the same type in the same operating conditions (excluding determined impact of a person, work as an entity, which MTBF is equal to the average lifetime. It is proposed to take the average service life as a reliability indicator of a pipeline. Durability, but not failsafety of the pipe guarantees pipeline functioning

  3. Solar/electric heating systems for the future energy system

    Energy Technology Data Exchange (ETDEWEB)

    Furbo, S.; Dannemand, M.; Perers, B. [and others

    2013-05-15

    The aim of the project is to elucidate how individual heating units for single family houses are best designed in order to fit into the future energy system. The units are based on solar energy, electrical heating elements/heat pump, advanced heat storage tanks and advanced control systems. Heat is produced by solar collectors in sunny periods and by electrical heating elements/heat pump. The electrical heating elements/heat pump will be in operation in periods where the heat demand cannot be covered by solar energy. The aim is to use the auxiliary heating units when the electricity price is low, e.g. due to large electricity production by wind turbines. The unit is equipped with an advanced control system where the control of the auxiliary heating is based on forecasts of the electricity price, the heat demand and the solar energy production. Consequently, the control is based on weather forecasts. Three differently designed heating units are tested in a laboratory test facility. The systems are compared on the basis of: 1) energy consumption for the auxiliary heating; 2) energy cost for the auxiliary heating; 3) net utilized solar energy. Starting from a normal house a solar combi system (for hot water and house heating) can save 20-30% energy cost, alone, depending on sizing of collector area and storage volume. By replacing the heat storage with a smart tank based on electric heating elements and a smart control based on weather/load forecast and electricity price information 24 hours ahead, another 30-40% can be saved. That is: A solar heating system with a solar collector area of about 10 m{sup 2}, a smart tank based on electric heating element and a smart control system, can reduce the energy costs of the house by at least 50%. No increase of heat storage volume is needed to utilize the smart control. The savings in % are similar for different levels of building insulation. As expected a heat pump in the system can further reduce the auxiliary electricity

  4. Comparison of Low-temperature District Heating Concepts in a Long-Term Energy System Perspective

    DEFF Research Database (Denmark)

    Lund, Rasmus Søgaard; Østergaard, Dorte Skaarup; Yang, Xiaochen

    2017-01-01

    District heating systems are important components in an energy efficient heat supply. With increasing amounts of renewable energy, the foundation for district heating is changing and the approach to its planning will have to change. Reduced temperatures of district heating are proposed...... as a solution to adapt it to future renewable energy systems. This study compares three alternative concepts for district heating temperature level: Low temperature (55/25 oC), Ultra-low temperature with electric boosting (45/25 oC), and Ultra-low temperature with heat pump boosting (35/20 oC) taking...... into account the grid losses, production efficiencies and building requirements. The scenarios are modelled and analysed in the analysis tool EnergyPLAN and compared on primary energy supply and socioeconomic costs. The results show that the low temperature solution (55/25 oC) has the lowest costs, reducing...

  5. PARAMETERS OF WATER CIRCULATION NETWORK FOR A DISTRICT HEATING AND COOLING SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In a district heating and cooling system, i.e. Beijing combined heating cooling and power (CHCP) system studied here, high temperature water generated by two cogeneration plants circulates through a network between the plants and heat substations. At heat substations, supply water of high temperature from the network drives absorption chillers for air-conditioning in summer and meets space heating demands in winter or domestic hot water demands by heat exchangers in the whole year. The parameters, i.e. supply/return water temperature in the network, has a great impact on primary energy consumption (PEC) of the absorption chillers, circulation pumps and domestic hot water (DHW), which is studied in this paper.

  6. Air leakage in residential solar heating systems

    Science.gov (United States)

    Shingleton, J. G.; Cassel, D. E.; Overton, R. L.

    1981-02-01

    A series of computer simulations was performed to evaluate the effects of component air leakage on system thermal performance for a typical residential solar heating system, located in Madison, Wisconsin. Auxiliary energy required to supplement solar energy for space heating was determined using the TRNSYS computer program, for a range of air leakage rates at the solar collector and pebble bed storage unit. The effects of heat transfer and mass transfer between the solar equipment room and the heated building were investigated. The effect of reduced air infiltration into the building due to pressurized by the solar air heating system were determined. A simple method of estimating the effect of collector array air leakage on system thermal performance was evaluated, using the f CHART method.

  7. Performance Analysis of Photovoltaic Water Heating System

    Directory of Open Access Journals (Sweden)

    Tomas Matuska

    2017-01-01

    Full Text Available Performance of solar photovoltaic water heating systems with direct coupling of PV array to DC resistive heating elements has been studied and compared with solar photothermal systems. An analysis of optimum fixed load resistance for different climate conditions has been performed for simple PV heating systems. The optimum value of the fixed load resistance depends on the climate, especially on annual solar irradiation level. Use of maximum power point tracking compared to fixed optimized load resistance increases the annual yield by 20 to 35%. While total annual efficiency of the PV water heating systems in Europe ranges from 10% for PV systems without MPP tracking up to 15% for system with advanced MPP trackers, the efficiency of solar photothermal system for identical hot water load and climate conditions is more than 3 times higher.

  8. Overview on the power supply systems for plasma instabilities control

    Energy Technology Data Exchange (ETDEWEB)

    Toigo, V., E-mail: vanni.toigo@igi.cnr.it [Consorzio RFX - EURATOM - ENEA Association, C.so Stati Uniti 4, 35127 Padova (Italy); Gaio, E.; Piovan, R.; Barp, M.; Bigi, M.; Ferro, A.; Finotti, C.; Novello, L.; Recchia, M.; Zamengo, A.; Zanotto, L. [Consorzio RFX - EURATOM - ENEA Association, C.so Stati Uniti 4, 35127 Padova (Italy)

    2011-10-15

    The paper presents an overview on the power supply (PS) systems for plasma instabilities control in fusion experiments, based on active control coils. First, the MHD instabilities and the approach to their control in Tokamaks and Reversed Field Pinches (RFPs) are described. Then, the features of MHD modes controls presently used in fusion experiments are reviewed. For the control systems based on active coils fed by fast power supplies, the typical requirements in terms of power, dynamics, accuracy and delay are summarized and discussed. Then, a survey on the technology available to design these types of PSs is given, together with the most suitable circuit topologies and guidelines for the design, on the basis of solutions adopted in existing experiments.

  9. A study of industrial hydrogen and syngas supply systems

    Science.gov (United States)

    Amos, W. J.; Solomon, J.; Eliezer, K. F.

    1979-01-01

    The potential and incentives required for supplying hydrogen and syngas feedstocks to the U.S. chemical industry from coal gasification systems were evaluated. Future hydrogen and syngas demand for chemical manufacture was estimated by geographic area and projected economics for hydrogen and syngas manufacture was estimated with geographic area of manufacture and plant size as parameters. Natural gas, oil and coal feedstocks were considered. Problem areas presently affecting the commercial feasibility of coal gasification discussed include the impact of potential process improvements, factors involved in financing coal gasification plants, regulatory barriers affecting coal gasification, coal mining/transportation, air quality regulations, and competitive feedstock pricing barriers. The potential for making coal gasification the least costly H2 and syngas supply option. Options to stimulate coal gasification system development are discussed.

  10. Istra district heating system. General technical report. Appendix 1 to the master plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-09-01

    The objective of the master plan project is to improve the heat supply in Istra. The considerable system losses from the fuel supplied to the end-users are one issue for improvement. At the same time, the current system operation results in poor quality heat for the consumers. Due to the inflexibility of the system the dwellings/premises of the consumers are either overheated or insufficiently heated. The financial situation in Istra, the legal ownership of the district heating system and consumers' lacking ability to pay limit the possibilities for system improvements. The Master Plan and Feasibility Study evaluates four different development scenarios. Each of the scenarios is compared to the current situation in Istra, where nothing is done to change the system, but only to operate the present system in a sustainable way. The sustainable operation of the district heating system includes all necessary renovations and component replacements necessary. The project does not take into account the present financial situation in Istra, which has resulted in less maintenance than necessary. This situation is not a comparable parameter, as it is not sustainable and will lead to a breakdown of the heat supply within a short time horizon. The General Technical Report evaluates the technical situation and describes system improvements at a general level. The intention with this report is to provide important information useful to other district heating companies in Russia. (au)

  11. Electric Power Supply of Meat Processing Enterprise through Utilization Heat of Compressor Station Secondary Energy Sources in Main Gasline

    Directory of Open Access Journals (Sweden)

    A. Nesenchuk

    2013-01-01

    Full Text Available The paper considers a structure of power consumption by a meat processing enterprise with indication of specific power consumption norms in accordance with product nomenclature. Schemes for supply of the enterprise with heat and cold through utilization of compressor station secondary energy sources in main gasline have been presented in the paper.

  12. Design of seasonal hydrogen storage systems for the energy supply by solar radiation, wind power and environmental heat; Auslegung saisonaler Wasserstoffspeicher fuer die Energieversorgung aus Solarstrahlung, Windkraft und Umgebungswaerme

    Energy Technology Data Exchange (ETDEWEB)

    Meurer, H.C.

    2000-07-01

    In the present study a design procedure for hydrogen storage systems in power plants with renewable energy is presented. The storage system consists of an electrolyzer, gas storage in high pressure tanks and reconversion into electricity by a fuel cell. This work is based on the experiences made by construction and operation of the demonstration plant PHOEBUS Juelich for Photovoltaik, Elektrolyse, Brennstoffzelle und Systemtechnik (photovoltaics, electrolysis, fuel cell and system engineering) at the Research Centre Juelich. These systems are treated by dynamic simulation in a high temporal resolution. The seasonal and the stochastical behaviour of the yield of renewable energy and energy consumption is taken into account by simulating over a time span of 17 years using measured meteorological data. For optimization the autarky-limit-procedure is introduced. A cost model is applied to the results of the simulation. The autarky-limit describes the correlation between the capacity of the installed gas tank and the rated power of the installed converters for renewable energy in case of exactly self-sufficient plant operation. Using the autarky-limit procedure, it is possible to size all major components for long-term operation at minimal costs. The procedure is applied for a modelled consumer at Research Centre Juelich site. Various configurations of the storage system are investigated and compared. More generalized statements about a reasonable use of hydrogen storage are derived from the results. (orig.) [German] In der vorliegenden Arbeit wird ein Auslegungsverfahren fuer Wasserstoffspeicher in Energieversorgungsanlagen mit erneuerbaren Energietraegern vorgestellt. Der Speicherpfad besteht aus Elektrolyse, Gasspeicherung in Hochdrucktanks und Rueckverstromung in einer Brennstoffzelle. Die Basis der Arbeit bilden die Erfahrungen mit Bau und Betrieb der Demonstrationsanlage PHOEBUS Juelich fuer Photovoltaik, Elektrolyse, Brennstoffzelle und Systemtechnik im

  13. Modern Solutions for Automation of Electrical Traction Power Supply Systems

    Directory of Open Access Journals (Sweden)

    Ana Mihaela Andreica

    2011-09-01

    Full Text Available This paper presents modern solutions for the automation of the electrical traction power supply system used in urban public transport (trams, trolleybuses and subway trains. The monitoring and control of this process uses SCADA distributed architectures, grouped around a central point (dispatcher who controls all field sensors, transmitters and actuators using programmable logical controllers. The presented applications refer to the Bucharest electrical transport infrastructure.

  14. Flexible procurement systems is key to supply chain sustainability

    OpenAIRE

    Surajit Bag

    2016-01-01

    Background: In this dynamic business environment, manufacturers are focusing primarily on delivery performance and competitive pricing to win orders. It is essential that manufacturers adopt flexible procurement systems (FPSs) in such an uncertain environment for business sustainability.Objectives: The purpose of the study is to identify the elements of FPSs and model the interrelationships between elements of FPSs and, finally, to understand how FPSs are linked with supply chain sustainabili...

  15. Systems for uninterrupted power supply; USV - ein starkes Stueck Sicherheit

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, D.; Soelter, W. [AEG SVS GmbH, Warstein-Belecke (Germany)

    1999-09-01

    The millennium bug is only one of the many potential hazards in information technology. Systems for uninterrupted power supply offer a solution. [German] Alle Welt spricht vom Jahr-2000-Problem (Y2K). Die Meinungen dazu reichen von Horror-Szenarien bis hin zum Ignorieren dieses Problems. Dabei steht fest: Das Jahr-2000-Problem ist nur eines unter vielen Gefahrenpotentialen fuer die Informationstechnik. Dabei lassen sich alle Stoerfaktoren, die aus der Energieversorgung resultieren mit einer USV beseitigen. USV sichern Geschaeftsablaeufe und Fertigungsprozesse. (orig.)

  16. 14 CFR 25.1326 - Pitot heat indication systems.

    Science.gov (United States)

    2010-01-01

    ....1326 Pitot heat indication systems. If a flight instrument pitot heating system is installed, an indication system must be provided to indicate to the flight crew when that pitot heating system is not... pitot heating system is switched “off”. (2) The pitot heating system is switched “on” and any pitot...

  17. AUTOMATION OF THE RESIDENTIAL BUILDING WATER SUPPLY SYSTEM PUMPING STATION

    Directory of Open Access Journals (Sweden)

    A. M. Kulia

    2016-08-01

    Full Text Available Essence of process of water-supply of apartment dwelling house is considered. The existent state over of automation of the pumping stations is brought. The task of development of the effective system of automatic control is put by them. Possibility of decision of task is shown by the use in the system of frequency transformer that feeds the electrodrives of pumps, and also due to perfection of algorithms of the pumps rotation frequency adjusting and logical management of their switching a sequence. The practical value of the use of the system is to increase dynamic.

  18. Transformation strategies of fossil central district heating supply to grids with an enhanced portion of renewable energies; Transformationsstrategien von fossiler zentraler Fernwaermeversorgung zu Netzen mit hoeheren Anteilen erneuerbarer Energien

    Energy Technology Data Exchange (ETDEWEB)

    Paar, Angelika; Herbert, Florian; Pehnt, Martin [ifeu-Institut fuer Energie- und Umweltforschung GmbH, Heidelberg (Germany); Ochse, Susanne; Richter, Stephan; Maier, Stefanie; Kley, Magalie [GEF Ingenieur AG, Leimen (Germany); Huther, Heiko; Kuehne, Jens; Weidlich, Ingo [AGFW - Der Energieeffizienzverband fuer Waerme, Kaelte und KWK e.V., Frankfurt am Main (Germany)

    2013-04-15

    A considerable portion of the primary energy consumption in Germany is used to provide process heat and space heating as well as for the hot water processing. The heat supply and the enhancement of the portion of renewable energy sources are particularly important for the reduction of greenhouse gas emissions. The contribution under consideration deals with the question of how the portion of renewable energy can be increased in existing district heating systems. The potential utilization of renewable energy sources in the district heating is analyzed systematically.

  19. Fundamental Study of a Combined Hyperthermia System with RF Capacitive Heating and Interstitial Heating

    OpenAIRE

    Saitoh, Yoshiaki; Hori, Junichi; 斉藤, 義明; 堀, 潤一

    2001-01-01

    Interstitial RF heating with an inserted electrode allows the heating position selection in a subject, but the narrow heating region is problematic. This study elucidates development of new interstitial RF heating methods, combining with external RF heating using paired electrodes, heating the subject broadly in advance in order to selectively extend the heating region. Two kinds of heating system were developed by controlling a differential mode and a common mode of RF currents. Heating expe...

  20. Fundamental Study of a Combined Hyperthermia System with RF Capacitive Heating and Interstitial Heating

    OpenAIRE

    Saitoh, Yoshiaki; Hori, Junichi; 斉藤, 義明; 堀, 潤一

    2001-01-01

    Interstitial RF heating with an inserted electrode allows the heating position selection in a subject, but the narrow heating region is problematic. This study elucidates development of new interstitial RF heating methods, combining with external RF heating using paired electrodes, heating the subject broadly in advance in order to selectively extend the heating region. Two kinds of heating system were developed by controlling a differential mode and a common mode of RF currents. Heating expe...

  1. Optimization of electrical supply systems of oil production installations

    Energy Technology Data Exchange (ETDEWEB)

    Nissenbaum, I.A.; Novoselov, Yu.B.; Tsekhnov, A.N.

    1979-01-01

    The problem of optimization of electrical system assumes determination of the method for constructing the system, the functioning of which would assure minimal values of the technical-economic criterion -- costs, which are the basic economic factor in construction and exploitation of the system. When designing electro-supply systems for oil production installations, in particular, the pump stations, three principal versions of the optimization problem are possible, which are determined by the different conditions of the system, the type of minimizing criteria and volume of optimizing parameters. The most difficult optimization of an electrical system is when it is characterized only by assumed values of active power flow, which are determined by the specific energy requirements of the planned technological processes and the type of equipment used. Second, the more common optimization problem is improvement of the existing electrical network, with established processes and equipment use. The third version is a developing system, in which as a result of introduction of new technological installations, or remodeling of old ones, and which may result in a sharp change or re-distribution of the active power supply. Determining operating regimen of the system and optimization of economic-technical criteria should be a result of large-scale calculation and simulation using a digital computer, and use of iteration and non-linear programming methods.

  2. Exergy performance of different space heating systems: A theoretical study

    DEFF Research Database (Denmark)

    Kazanci, Ongun Berk; Shukuya, Masanori; Olesen, Bjarne W.

    2016-01-01

    Three space heating systems (floor heating with different floor covering resistances, radiator heating with different working temperatures, warm-air heating with and without heat recovery) were compared using a natural gas fired condensing boiler as the heat source. For the floor heating systems......, the effects of floor covering resistance on the whole system performance were studied using two heat sources; a natural gas fired condensing boiler and an air-source heat pump. The heating systems were also compared in terms of auxiliary exergy use for pumps and fans. The low temperature floor heating system...

  3. Microbiology of aquatic environments: Characterizations of the microbiotas of municipal water supplies, the International Space Station Internal Active Thermal Control System's heat transport fluid, and US Space Shuttle drinking water

    Science.gov (United States)

    Bernardini, James Nicholas, III

    An understanding of the microbiota within life support systems is essential for the prolonged presence of humans in space. This is because microbes may cause disease or induce biofouling and/or corrosion within spacecraft water systems. It is imperative that we develop effective high-throughput technologies for characterizing microbial populations that can eventually be used in the space environment. This dissertation describes testing and development of such methodologies, targeting both bacteria and viruses in water, and examines the bacterial and viral diversity within two spacecraft life support systems. The bacterial community of the International Space Station Internal Active Thermal Control System (IATCS) was examined using conventional culture-based and advanced molecular techniques including adenosine triphosphate (ATP) and Limulus Amebocyte Lysate (LAL) assays, direct microscopic examination, and analyses of 16S rRNA gene libraries from the community metagenome. The cultivable heterotrophs of the IATCS fluids ranged from below detection limit to 1.1x10 5/100 ml, and viable cells, measured by ATP, ranged from 1.4x10 3/100 ml to 7.7x105/100 ml. DNA extraction, cloning, sequencing, and bioinformatic analysis of the clones from 16S RNA gene libraries showed members of the firmicutes, alpha, beta, and gamma-proteobacteria to be present in the fluids. This persistent microbial bioburden and the presence of probable metal reducers, biofilm formers, and opportunistic pathogens illustrate the need for better characterization of bacterial communities present within spacecraft fluids. A new methodology was developed for detection of viruses in water using microarrays. Samples were concentrated by lyophilization, resuspended and filtered (0.22microm). Viral nucleic acids were then extracted, amplified, fluorescently labeled and hybridized onto a custom microarray with probes for ˜1000 known viruses. Numerous virus signatures were observed. Human Adenovirus C and

  4. Experimental performance of a waste heat recovery and utilization system with a looped water-in-steel heat pipe

    Energy Technology Data Exchange (ETDEWEB)

    Habeebullah, M.H.; Akyurt, M.; Najjar, Y.S.H.; El-Kalay, A.K. [King Abdulaziz Univ., Jeddah (Saudi Arabia). College of Engineering

    1998-07-01

    An experimental facility is described for the recovery, by means of heat-pipes, of waste-heat from exhaust gases, and the utilization of the recovered energy to cool ambient air. To this end, heat of combustion gases, generated in a stainless-steel combustion chamber, is recovered from the stack by means of a heat-pipe system. The recovered heat is utilized to run a modified commercial aqua-ammonia absorption chiller. Chilled water from the chiller is supplied to a fan-coil type cooling tunnel to cool the intake air of a (conceptual) gas turbine engine to boost its performance. It is concluded from test results that the experimental facility performs well, and that it behaves as predicted by modeling and simulation studies. The system is able to extract between 70 and 93% of the technically recoverable energy from exhaust gases, and utilizes the extracted energy to cool air. (Author)

  5. Optimising corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.; Andersen, A.

    2002-01-01

    A three-year project - financially supported by the Nordic Industrial Fund - on monitoring of corrosion in district heating systems has been initiated with participation of researchers and industrial partners in Denmark, Finland, Iceland, Norway and Sweden. The primary objective of the project...... is to improve the quality control in district heating systems by corrosion monitoring. In Danish systems electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR), high-sensitive electrical resistance (ER) technology, crevice corrosion probes, as well as weight loss coupons...

  6. District Heating Systems Performance Analyses. Heat Energy Tariff

    Science.gov (United States)

    Ziemele, Jelena; Vigants, Girts; Vitolins, Valdis; Blumberga, Dagnija; Veidenbergs, Ivars

    2014-12-01

    The paper addresses an important element of the European energy sector: the evaluation of district heating (DH) system operations from the standpoint of increasing energy efficiency and increasing the use of renewable energy resources. This has been done by developing a new methodology for the evaluation of the heat tariff. The paper presents an algorithm of this methodology, which includes not only a data base and calculation equation systems, but also an integrated multi-criteria analysis module using MADM/MCDM (Multi-Attribute Decision Making / Multi-Criteria Decision Making) based on TOPSIS (Technique for Order Performance by Similarity to Ideal Solution). The results of the multi-criteria analysis are used to set the tariff benchmarks. The evaluation methodology has been tested for Latvian heat tariffs, and the obtained results show that only half of heating companies reach a benchmark value equal to 0.5 for the efficiency closeness to the ideal solution indicator. This means that the proposed evaluation methodology would not only allow companies to determine how they perform with regard to the proposed benchmark, but also to identify their need to restructure so that they may reach the level of a low-carbon business.

  7. How dangerous is underfloor heating for the heating system

    Energy Technology Data Exchange (ETDEWEB)

    Musil, V.

    1981-01-01

    Depending on the working temperature, quality of the material and surface, oxygen diffuses through the plastic pipes into the heating water, is transported to the boiler and is separated out at hot places. A brown FeOOH slurry is formed. Black magnetite slurry (Fe/sub 3/O/sub 4/) is formed without free oxygen. About 25 kg of iron per annum are worn away in a heating system having 10,000 metres of 1/2 inch plastic pies with a water temperature of 40/sup 0/C, which is evenly distributed is a reduction of wall thickness of 0.25 mm. Corrosion on the water side also occurs with open heating systems, excessiveley large circulating pipes and water losses. If these possibilities do not exist, and if there is an oxygen content of more than 0.1 mg/litre in the water, then the separation of the plastic circuit and the use of a heat exchanger is recommended. Hydrazine or sodium sulphide can be added as inhibitors.

  8. Numerical study of heat pipe application in heat recovery systems

    Energy Technology Data Exchange (ETDEWEB)

    Song Lin; Broadbent, John; McGlen, Ryan [Thermacore Europe, Ashington (United Kingdom)

    2005-01-01

    Heat pipes are two-phase heat transfer devices with extremely high effective thermal conductivity. They can be cylindrical or planar in structure. Heat pipes can be embedded in a metal cooling plate, which is attached to the heat source, and can also be assembled with a fin stack for fluid heat transfer. Due to the high heat transport capacity, heat exchangers with heat pipes have become much smaller than traditional heat exchangers in handling high heat fluxes. With the working fluid in a heat pipe, heat can be absorbed on the evaporator region and transported to the condenser region where the vapour condenses releasing the heat to the cooling media. Heat pipe technology has found increasing applications in enhancing the thermal performance of heat exchangers in microelectronics, energy and other industrial sectors. Utilisation of a heat pipe fin stack in the drying cycle of domestic appliances for heat recovery may lead to a significant energy saving in the domestic sector. However, the design of the heat pipe heat exchanger will meet a number of challenges. This paper presents a design method by using CFD simulation of the dehumidification process with heat pipe heat exchangers. The strategies of simulating the process with heat pipes are presented. The calculated results show that the method can be further used to optimise the design of the heat pipe fin stack. The study suggests that CFD modelling is able to predict thermal performance of the dehumidification solution with heat pipe heat exchangers. (Author)

  9. Thermal Advantages for Solar Heating Systems with a Glass Cover with Antireflection Surfaces

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    2003-01-01

    Investigations elucidate how a glass cover with antireflection surfaces can improve the efficiency of a solar collector and the thermal performance of solar heating systems. The transmittances for two glass covers for a flat-plate solar collector were measured for different incidence angles...... was determined for different solar heating systems. Three systems were investigated: solar domestic hot water systems, solar heating systems for combined space heating demand and domestic hot water supply, and large solar heating plants. The yearly thermal performance of the systems was calculated by detailed...... simulation models with collectors with a normal glass cover and with a glass cover with antireflection surfaces. The calculations were carried out for different solar fractions and temperature levels of the solar heating systems. These parameters influence greatly the thermal performance associated...

  10. Study on the System Design of a Solar Assisted Ground Heat Pump System Using Dynamic Simulation

    Directory of Open Access Journals (Sweden)

    Min Gyung Yu

    2016-04-01

    Full Text Available Recently, the use of hybrid systems using multiple heat sources in buildings to ensure a stable energy supply and improve the system performance has gained attention. Among them, a heat pump system using both solar and ground heat was developed and various system configurations have been introduced. However, establishing a suitable design method for the solar-assisted ground heat pump (SAGHP system including a thermal storage tank is complicated and there are few quantitative studies on the detailed system configurations. Therefore, this study developed three SAGHP system design methods considering the design factors focused on the thermal storage tank. Using dynamic energy simulation code (TRNSYS 17, individual performance analysis models were developed and long-term quantitative analysis was carried out to suggest optimum design and operation methods. As a result, it was found that SYSTEM 2 which is a hybrid system with heat storage tank for only a solar system showed the highest average heat source temperature of 14.81 °C, which is about 11 °C higher than minimum temperature in SYSTEM 3. Furthermore, the best coefficient of performance (COP values of heat pump and system were 5.23 and 4.32 in SYSYEM 2, using high and stable solar heat from a thermal storage tank. Moreover, this paper considered five different geographical and climatic locations and the SAGHP system worked efficiently in having high solar radiation and cool climate zones and the system COP was 4.51 in the case of Winnipeg (Canada where the highest heating demand is required.

  11. Solar heating system installed at Troy, Ohio

    Science.gov (United States)

    1980-01-01

    The completed system was composed of three basic subsystems: the collector system consisting of 3,264 square feet of Owens Illinois evacuated glass tube collectors; the storage system which included a 5,000 gallon insulated steel tank; and the distribution and control system which included piping, pumping and heat transfer components as well as the solemoid activated valves and control logic for the efficient and safe operation of the entire system. This solar heating system was installed in an existing facility and was, therefore, a retrofit system. Extracts from the site files, specifications, drawings, installation, operation and maintenance instructions are included.

  12. Thermal Efficiency of Cogeneration Units with Multi-Stage Reheating for Russian Municipal Heating Systems

    Directory of Open Access Journals (Sweden)

    Evgeny Lisin

    2016-04-01

    Full Text Available This paper explores the layout of an optimum process for supplying heat to Russian municipal heating systems operating in a market environment. We analyze and compare the standard cogeneration unit design with two-stage reheating of service water coming from controlled extraction locations and layouts that employ three in-line reheaters with heat the supply controlled by a rotary diaphragm and qualitative/quantitative methods (so-called “uncontrolled extraction”. Cogeneration unit designs are benchmarked in terms of their thermal efficiency expressed as a fuel consumption rate. The specific fuel consumption rate on electricity production is viewed as a key parameter of thermal efficiency.

  13. Optimization of operation of energy supply systems with co-generation and absorption refrigeration

    Directory of Open Access Journals (Sweden)

    Stojiljković Mirko M.

    2012-01-01

    Full Text Available Co-generation systems, together with absorption refrigeration and thermal storage, can result in substantial benefits from the economic, energy and environmental point of view. Optimization of operation of such systems is important as a component of the entire optimization process in pre-construction phases, but also for short-term energy production planning and system control. This paper proposes an approach for operational optimization of energy supply systems with small or medium scale co-generation, additional boilers and heat pumps, absorption and compression refrigeration, thermal energy storage and interconnection to the electric utility grid. In this case, the objective is to minimize annual costs related to the plant operation. The optimization problem is defined as mixed integer nonlinear and solved combining modern stochastic techniques: genetic algorithms and simulated annealing with linear programming using the object oriented “ESO-MS” software solution for simulation and optimization of energy supply systems, developed as a part of this research. This approach is applied to optimize a hypothetical plant that might be used to supply a real residential settlement in Niš, Serbia. Results are compared to the ones obtained after transforming the problem to mixed 0-1 linear and applying the branch and bound method.

  14. Heating, ventilation and air conditioning system modelling

    Energy Technology Data Exchange (ETDEWEB)

    Whalley, R.; Abdul-Ameer, A. [British University in Dubai (United Arab Emirates)

    2011-03-15

    Heating, ventilation and air conditioning modelling methods, for large scale, spatially dispersed systems are considered. Existing techniques are discussed and proposals for the application of novel analysis approaches are outlined. The use of distributed-lumped parameter procedures enabling the incorporation of the relatively concentrated and significantly dispersed, system element characteristics, is advocated. A dynamic model for a heating, ventilation and air conditioning system comprising inlet and exhaust fans, with air recirculation, heating/cooling and filtration units is presented. Pressure, airflow and temperature predictions within the system are computed following input, disturbance changes and purging operations. The generalised modelling advancements adopted and the applicability of the model for heating, ventilation and air conditioning system simulation, re-configuration and diagnostics is emphasised. The employment of the model for automatic, multivariable controller design purposes is commented upon. (author)

  15. Governing Uncertainties in Sustainable Energy Transitions—Insights from Local Heat Supply in Switzerland

    Directory of Open Access Journals (Sweden)

    Basil Bornemann

    2016-11-01

    Full Text Available The governance of sustainable energy transitions (SET is facing multiple technological, economic, societal and political uncertainties. In practice, these energy-related uncertainties play a role not only at the level of “major politics,” but also in the policymaking of local decision makers and planners. This paper seeks to attain a more differentiated understanding of how uncertainties concerning the energy transition play out and are dealt with in policymaking and planning “on the ground.” To do so, the paper combines conceptual reflections with an explorative empirical study on local heat supply policy in Switzerland. In conceptual regards, it proposes some distinctions of types of uncertainties related to energy transitions, and a typology of strategic decision options for dealing with uncertainty. On this basis, the paper reveals similarities and differences regarding the perception of uncertainties and ways of dealing with them in a number of Swiss cities. These insights evoke further questions about the causes and effects of different sensitivities to uncertainty and ways of dealing with them.

  16. Alternative power supply systems for remote industrial customers

    Science.gov (United States)

    Kharlamova, N. V.; Khalyasmaa, A. I.; Eroshenko, S. A.

    2017-06-01

    The paper addresses the problem of alternative power supply of remote industrial clusters with renewable electric energy generation. As a result of different technologies comparison, consideration is given to wind energy application. The authors present a methodology of mean expected wind generation output calculation, based on Weibull distribution, which provides an effective express-tool for preliminary assessment of required installed generation capacity. The case study is based on real data including database of meteorological information, relief characteristics, power system topology etc. Wind generation feasibility estimation for a specific territory is followed by power flow calculations using Monte Carlo methodology. Finally, the paper provides a set of recommendations to ensure safe and reliable power supply for the final customers and, subsequently, to provide sustainable development of the regions, located far from megalopolises and industrial centres.

  17. Air supply system for an internal combustion engine

    Energy Technology Data Exchange (ETDEWEB)

    Eftink, A.

    1992-06-11

    The present invention describes a system for supplying the primary combustion air to a reciprocating piston internal combustion engine including a trochoidal chamber air pump having a pair of pumping chambers interposed between an air intake and each of the cylinders of the engine. Each pumping chamber has an air inlet connected to an air intake, and an air outlet that is connected to the cylinders. In a two-cycle mode of operation, each pumping chamber outlet is connected to one engine cylinder. In a four-cycle mode of operation, each pumping chamber outlet is connected to a pair of cylinders to supply air during the intake stroke. The input shaft of the trochoidal chamber air pump is driven by, and may be connected to, the crankshaft of the engine so as to rate on a 1:1 ratio. (author)

  18. Using integrated information systems in supply chain management

    Science.gov (United States)

    Gonzálvez-Gallego, Nicolás; Molina-Castillo, Francisco-Jose; Soto-Acosta, Pedro; Varajao, Joao; Trigo, Antonio

    2015-02-01

    The aim of this paper is to empirically test not only the direct effects of information and communication technology (ICT) capabilities and integrated information systems (IS) on firm performance, but also the moderating role of IS integration along the supply chain in the relationship between ICT external and capabilities and business performance. Data collected from 102 large Iberian firms from Spain and Portugal are used to test the research model. The hierarchical multiple regression analysis is employed to test the direct effects and the moderating relationships proposed. Results show that external and internal ICT capabilities are important drivers of firm performance, while merely having integrated IS do not lead to better firm performance. In addition, a moderating effect of IS integration in the relationship between ICT capabilities and business performance is found, although this integration only contributes to firm performance when it is directed to connect with suppliers or customers rather than when integrating the whole supply chain.

  19. Study on Problems and Countermeasures of Rural Public Goods Supplying System

    Institute of Scientific and Technical Information of China (English)

    JIANG Hua

    2006-01-01

    In current China, the main problem existing in the rural public goods supplying system is the unbalanced condition of public goods supply, and the chief reason for which is unitary system of supply main body.Thus the leading countermeasure for corner of public goods supply is to reform the present unitary rural public goods supplying system, to strengthen functional transfer of rural grass-roots directive organization, to adopt diversified mode and provide public goods on the base of overall planning of urban and rural areas and to implement unitary and diversified supplying strategy. In this way, supplying efficiency of the rural public goods will be improved.

  20. Development of Solar Electricity Supply System in India: An Overview

    Directory of Open Access Journals (Sweden)

    Sandeep Kumar Gupta

    2013-01-01

    Full Text Available Solar electricity supply system has grown at very rapid pace in India during the last few years. A total of 1047.84 MW of grid connected photovoltaic projects and 160.8 MW of off-grid systems have been commissioned under different policy mechanisms between January 2010 and November 2012. It is observed that solar capacity development has achieved a greater height under state policies (689.81 MW than others. A study is made in this paper of various national and state level schemes, incentives, packages, instruments, and different mechanisms to promote solar photovoltaics and its effectiveness.

  1. In situ heat treatment process utilizing a closed loop heating system

    Energy Technology Data Exchange (ETDEWEB)

    Vinegar, Harold J. (Bellaire, TX); Nguyen, Scott Vinh (Houston, TX)

    2010-12-07

    Systems and methods for an in situ heat treatment process that utilizes a circulation system to heat one or more treatment areas are described herein. The circulation system may use a heated liquid heat transfer fluid that passes through piping in the formation to transfer heat to the formation. In some embodiments, the piping may be positioned in at least two of the wellbores.

  2. Liquid fueled external heating system for STM4-120 Stirling engine

    Science.gov (United States)

    Meijer, R. J.; Ziph, B.; Godett, T. M.

    1985-01-01

    The STM4-120 Stirling engine, currently under development at Stirling Thermal Motors, Inc., is a 40 kW variable stroke engine with indirect heating using a sodium heat pipe. The engine is functionally separated into an application independent Energy Conversion Unit (ECU) consisting of the Stirling cycle and drive heated by condensing sodium and the application dependent External Heating System (EHS), designed to supply the ECU with sodium vapor heated by the particular energy source, connected by tubes with mechanical couplings. This paper describes an External Heating System for the STM4-120 ECU designed for the combustion of liquid fuel, comprised of a recuperative preheater, a combustion chamber, and a heat exchanger/evaporator where heat is transferred from the flue gas to the sodium causing it to evaporate. The design concept and projected performance are described and discussed.

  3. Solar-heating system performance tests

    Science.gov (United States)

    1979-01-01

    Report contains results of performance tests on complete system for solar space and hot-water heating system that uses commercially available components. Results were used to determine system suitability for field installation and to generate performance data base for comparison with future tests on field installed systems.

  4. Rankine cycle waste heat recovery system

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Nelson, Christopher R.

    2016-05-10

    This disclosure relates to a waste heat recovery (WHR) system and to a system and method for regulation of a fluid inventory in a condenser and a receiver of a Rankine cycle WHR system. Such regulation includes the ability to regulate the pressure in a WHR system to control cavitation and energy conversion.

  5. Rankine cycle waste heat recovery system

    Energy Technology Data Exchange (ETDEWEB)

    Ernst, Timothy C.; Nelson, Christopher R.

    2014-08-12

    This disclosure relates to a waste heat recovery (WHR) system and to a system and method for regulation of a fluid inventory in a condenser and a receiver of a Rankine cycle WHR system. Such regulation includes the ability to regulate the pressure in a WHR system to control cavitation and energy conversion.

  6. Solar heating and hot water system installed at Arlington Raquetball Club, Arlington, Virginia

    Science.gov (United States)

    1981-01-01

    A solar space and water heating system is described. The solar energy system consists of 2,520 sq. ft. of flat plate solar collectors and a 4,000 gallon solar storage tank. The transfer medium in the forced closed loop is a nontoxic antifreeze solution (50 percent water, 50 percent propylene glycol). The service hot water system consists of a preheat coil (60 ft. of 1 1/4 in copper tubing) located in the upper third of the solar storage tank and a recirculation loop between the preheat coil and the existing electric water heaters. The space heating system consists of two separate water to air heat exchangers located in the ducts of the existing space heating/cooling systems. The heating water is supplied from the solar storage tank. Extracts from site files, specification references for solar modifications to existing building heating and hot water systems, and installation, operation and maintenance instructions are included.

  7. Prototype solar-heating system - installation manual

    Science.gov (United States)

    1978-01-01

    Manual for prototype solar-heating system gives detailed installation procedures for each of seven subsystems. Procedures for operation and maintenance are also included. It discusses architectural considerations, building construction considerations, and checkout-test procedures.

  8. Modular solar-heating system - design package

    Science.gov (United States)

    Sinton, D. S.

    1979-01-01

    Compilation contains design, performance, and hardware specifications in sufficient detail to fabricate or procure materials and install, operate, and maintain complete modular solar heating and hot water system for single family size dwellings.

  9. Solar Heating System at a Racquetball Club

    Science.gov (United States)

    1982-01-01

    Detailed 93-page report describes Arlington, Virginia racquetball club which obtains heat and hot water for its support area from solar collectors. Report explains modes of operation of system and details of acceptance-test plan.

  10. Heat reduction of the MWD telemetry system

    OpenAIRE

    Matviykiv, Taras

    2012-01-01

    In this paper the simplified thermal model of conventional downhole MWD (Measurements While Drilling) telemetry system has been made. The heat reduction methods for the IC (integrated circuits) components of downhole drilling tools have been analyzed.

  11. Design information for solar-heating systems

    Science.gov (United States)

    1979-01-01

    Report contains preliminary design information for two solar-heating and hot water systems presently under development. Information includes quality control data, special tooling specifications, hazard analysis, and preliminary training program for installation contractors.

  12. Modular solar-heating system - design package

    Science.gov (United States)

    Sinton, D. S.

    1979-01-01

    Compilation contains design, performance, and hardware specifications in sufficient detail to fabricate or procure materials and install, operate, and maintain complete modular solar heating and hot water system for single family size dwellings.

  13. Electronics in cars: consequences for the energy-supply system

    Science.gov (United States)

    Beil, Falk

    The amount of electronics in cars is constantly increasing. Thus, the question arises, whether the current wiring designs will continue to be able to meet the required output related to this increase in the future. Which consequences result, then, for the design of the wiring system and its components? An examination of the electrical consumers currently installed in motor vehicles, and of those planned for future use, shows that the wiring system load during driving will increase to as much as 2000 W. Many new devices, such as the telephone, will also enjoy increasing use while the vehicle is at a standstill, which will result in the type of wiring system load changing in the future. In addition to this, loading will increase due to greater traffic density; the vehicle will be operated more often at idling speed, leading to a reduction in the available current. Thus, a balanced current supply can no longer be ensured with present designs. That means new energy supply concepts are required, e.g. the 24 V wiring system and energy management. In addition, the wiring system components must be optimized. This particularly applies to the battery, which must be further developed in order to obtain increased cell strength, a longer service life and improved temperature stability.

  14. Performance of constructed wetland system for public water supply.

    Science.gov (United States)

    Elias, J M; Salati Filho, E; Salati, E

    2001-01-01

    The project is being conducted in the town of Analândia, São Paulo, Brazil. The constructed wetlands system for water supply consists of a channel with floating aquatic macrophytes, HDS system (Water Decontamination with Soil-Patent PI 850.3030), chlorinating system, filtering system and distribution. The project objectives include investigating the process variables to further optimize design and operation factors, evaluating the relation of nutrients and plants development, biomass production, shoot development, nutrient cycling and total and fecal coliforms removal, comparing the treatment efficiency among the seasons of the year; and moreover to compare the average values obtained between February and June 1998 (Salati et al., 1998) with the average obtained for the same parameters between March and June 2000. Studies have been developed in order to verify during one year the drinking quality of the water for the following parameters: turbidity, color, pH, dissolved oxygen, total of dissolved solids, COD, chloride, among others, according to the Ministry of Health's Regulation 36. This system of water supply projected to treat 15 L s(-1) has been in continuous operation for 2 years, it was implemented with support of the National Environment Fund (FNMA), administered by the Center of Environmental Studies (CEA-UNESP), while the technical supervision and design were performed by the Institute of Applied Ecology. The actual research project is being supported by FAPESP.

  15. Open fireplace furnace as an adequate heating system

    Energy Technology Data Exchange (ETDEWEB)

    Terbrack, E.

    The fireplace furnace is a furnace for the open fireplace. It is connected to the existing fuel-oil or gas central heating and is used for house heating and warm water preparation when the fire in the fireplace is on. It combines the romanticism of the open fireplace with the necessity of saving fuel oil and gas, ensuring heat supply.

  16. Optimal control of a fuel cell/wind/PV/grid hybrid system with thermal heat pump load

    CSIR Research Space (South Africa)

    Sichilalu, S

    2016-10-01

    Full Text Available This paper presents an optimal energy management strategy for a grid-tied photovoltaic–wind-fuel cell hybrid power supply system. The hybrid system meets the load demand consisting of an electrical load and a heat pump water heater supplying thermal...

  17. Alignment of Information Systems with Supply Chains: Impacts on Supply Chain Performance and Organizational Performance

    Science.gov (United States)

    Qrunfleh, Sufian M.

    2010-01-01

    Over the past decade, an important focus of researchers has been on supply chain management (SCM), as many organizations believe that effective SCM is the key to building and sustaining competitive advantage for their products/services. To manage the supply chain, companies need to adopt an SCM strategy (SCMS) and implement appropriate SCM…

  18. Alignment of Information Systems with Supply Chains: Impacts on Supply Chain Performance and Organizational Performance

    Science.gov (United States)

    Qrunfleh, Sufian M.

    2010-01-01

    Over the past decade, an important focus of researchers has been on supply chain management (SCM), as many organizations believe that effective SCM is the key to building and sustaining competitive advantage for their products/services. To manage the supply chain, companies need to adopt an SCM strategy (SCMS) and implement appropriate SCM…

  19. A Suggestion for Safeguards System under Nuclear Supply Assurance Environment

    Energy Technology Data Exchange (ETDEWEB)

    Jo, Seong Youn [Korea Institute of Nuclear Non-proliferation and Control, Daejeon (Korea, Republic of)

    2009-05-15

    Various ideas about nuclear fuel supply assurance have been proposed with the expectation of a new era of 'Nuclear Renaissance.' The possibility is ever than high now as the environmental impact due to the fossil fuel burning is worsening. But there are several obstacles to realize the resurrection of nuclear power as promising energy source in the future. The disposal of high radioactive wastes like nuclear spent fuel could be the first one that everyone can imagine, because those wastes are regarded as one of the direct threat to human health. But the most dangerous threat can be materialized through the diversion of nuclear material, if some malicious actors like some rogue states or terrorist groups take chance of the nuclear industry booming. Most supply assurance ideas based on multilateral approach provide the way to provide nuclear fuel while limiting dissipation of sensitive technologies. But regarding the safeguards implementation under the supply assurance environment, it seems that any appropriate approach has not been prepared. It is prerequisite to establish safeguards implementation system for multilateral facilities prior to their actual operation.

  20. Geothermal heat pump system assisted by geothermal hot spring

    Science.gov (United States)

    Nakagawa, M.; Koizumi, Y.

    2016-01-01

    The authors propose a hybrid geothermal heat pump system that could cool buildings in summer and melt snow on the pedestrian sidewalks in winter, utilizing cold mine water and hot spring water. In the proposed system, mine water would be used as cold thermal energy storage, and the heat from the hot spring after its commercial use would be used to melt snow for a certain section of sidewalks. Neither of these sources is viable for direct use application of geothermal resources, however, they become contributing energy factors without producing any greenhouse gases. To assess the feasibility of the proposed system, a series of temperature measurements in the Edgar Mine (Colorado School of Mines' experimental mine) in Idaho Springs, Colorado, were first conducted, and heat/mass transfer analyses of geothermal hot spring water was carried out. The result of the temperature measurements proved that the temperature of Edgar Mine would be low enough to store cold groundwater for use in summer. The heat loss of the hot spring water during its transportation was also calculated, and the heat requirement for snow melt was compared with the heat available from the hot spring water. It was concluded that the heat supply in the proposed usage of hot spring water was insufficient to melt the snow for the entire area that was initially proposed. This feasibility study should serve as an example of "local consumption of locally available energy". If communities start harnessing economically viable local energy in a responsible manner, there will be a foundation upon which to build a sustainable community.

  1. Economic Assessment of Rural District Heating by Bio-Steam Supplied by a Paper Mill in Canada

    Science.gov (United States)

    Marinova, Mariya; Beaudry, Catherine; Taoussi, Abdelaziz; Trepanier, Martin; Paris, Jean

    2008-01-01

    The article investigates the feasibility of district heating in a small town adjacent to a Kraft pulp mill in eastern Canada. A detailed heat demand analysis is performed for all buildings using a geographical information system and archived data provided by the municipality. The study shows that the entire space heating requirement of the town…

  2. Hybrid solar-wind installation prospects for hot water and heating supply of private homes in the Absheron peninsula conditions of the Republic of Azerbaijan

    Directory of Open Access Journals (Sweden)

    Arzu Huseynov

    2015-12-01

    Full Text Available This paper analyses the environmental problems arising from the use of traditional energy resources for the production of electricity and heat. The advantages of replacing conventional energy resources and shifting to wind and solar energy technologies are explained. The possibilities of the combined use of solar and wind energy to provide an average family of 5 people with hot water and heating are explored. Experimental results were obtained from full-scale tests under prevailing conditions at Baku. Solar-wind hybrid systems for heating and hot water were designed and developed at the Institute of Radiation Problems of the Azerbaijan National Academy of Sciences. The paper also examines the possibility of supplying a family of 5 people with hot water produced by solar energy year-round and presents the results of the calculation of the energy balance of such facility.DOI: http://dx.doi.org/10.5755/j01.erem.71.3.12274

  3. Solar heating system installed at Lynchburg, VA

    Energy Technology Data Exchange (ETDEWEB)

    1976-12-01

    A detailed design report for a retrofitted solar heating and cooling system for a 1780 square foot office building is presented. The system is composed of a 400 square foot flat plate collector, a 2,000 gallon storage tank, a gas auxiliary boiler, a duct distribution system utilizing a hot water duct coil and water-to-air heat pump, and a hot water preheater. The control system, data acquisition system, technical data, and maintenance procedure are discussed. Detailed specifications, circuits, and drawings for the components are included. (WHK)

  4. Evaluation of integration of solar energy into the district heating system of the city of Velika Gorica

    Directory of Open Access Journals (Sweden)

    Felipe Andreu Javier

    2016-01-01

    Full Text Available In the current situation the district heating system supplies the 32% of the total thermal consumption in the City of Velika Gorica. The main issue in the district heating system is the utilization of 14 small and distributed heat plants, each providing heat to a separate and individually disconnected heating grid. Reduction of costs and CO2 emissions can be reached with a high penetration of renewable sources. The aim of this paper is to evaluate and design the integration of a Central Solar Heating Plant with Seasonal Storage into the district heating system of the City. An economic assessment was made with a pessimistic and an optimistic prediction of the solar heat cost for ground mounted collectors and roof mounted collectors. The seasonal storage was chosen to be pit thermal energy storage; the system was modeled as a low-temperature district heating system with the real thermal demands of a district heating plant.

  5. Leaks in the internal water supply piping systems

    Directory of Open Access Journals (Sweden)

    Orlov Evgeniy Vladimirovich

    2015-03-01

    Full Text Available Great water losses in the internal plumbing of a building lead to the waste of money for a fence, purification and supply of water volumes in excess. This does not support the concept of water conservation and resource saving lying today in the basis of any building’s construction having plumbing. Leakage means unplanned of water losses systems in domestic water supply systems (hot or cold as a result of impaired integrity, complicating the operation of a system and leading to high costs of repair and equipment restoration. A large number of leaks occur in old buildings, where the regulatory service life of pipelines has come to an end, and the scheduled repair for some reason has not been conducted. Steel pipelines are used in the systems without any protection from corrosion and they get out of order. Leakages in new houses are also not uncommon. They usually occur as a result of low-quality adjustment of the system by workers. It also important to note the absence of certain skills of plumbers, who don’t conduct the inspections of in-house systems in time. Sometimes also the residents themselves forget to keep their pipeline systems and water fittings in their apartment in good condition. Plumbers are not systematically invited for preventive examinations to detect possible leaks in the domestic plumbing. The amount of unproductive losses increases while simultaneous use of valve tenants, and at the increase of the number of residents in the building. Water leaks in the system depend on the amount of water system piping damages, and damages of other elements, for example, water valves, connections, etc. The pressure in the leak area also plays an important role.

  6. Considerations on Risk in Supply Chain Management Information Systems Implementation

    Directory of Open Access Journals (Sweden)

    Valentin-Petru Măzăreanu

    2013-02-01

    Full Text Available Innovation in information and communication technologies resulted in the digital revolution. This kind of revolution is changing the way people work, learn, communicate and manage their businesses. Due to the need to achieve the competitive advantage and to meet the business requirements, we are witnessing an increasing shift from business to e-business and mobile business. In this kind of world solutions like Supply Chain Management (SCM are increasingly appearing. The business success depends on how effective the information system works. Any interruption of the information system will inevitably lead to business loss. To ensure the successful implementation of a SCM project it is necessary to study even from the early stages which are the possible actions / risks / obstacles which might damage in one way or another the execution of the project. The role of the literature and case studies review in the field of interest is undeniable because it provides us with access to the so-called lessons-learned. By using this approach, in this paper, we present the most common risks and risk sources encountered in the implementation projects of SCM type information systems. We also propose a risk identification framework that can be used in the early stages of the implementation project of a Supply Chain Management information system.

  7. Regional Energy Planning Tool for Renewable Integrated Low-Energy District Heating Systems

    DEFF Research Database (Denmark)

    Tol, Hakan; Dincer, Ibrahim; Svendsen, Svend

    2013-01-01

    Low-energy district heating systems, operating at low temperature of 55 °C as supply and 25°C as return, can be the energy solution as being the prevailing heating infrastructure in urban areas, considering future energy schemesaiming at increased exploitation of renewable energy sources together...... with low-energy houses in focus with intensified energy efficiency measures. Employing low-temperature operation allows the ease to exploit not only any type of heat source but also low-grade sources, i.e., renewable and industrial waste heat, which would otherwise be lost. In this chapter, a regional...... energy planning tool is described considered with various energy conversion systems based on renewable energy sources to be supplied to an integrated energy infrastructure involving a low-energy district heating, a district cooling, and an electricity grid. The developed tool is performed for two case...

  8. Solar heating and hot water system installed at Shoney's Restaurant, North Little Rock, Arkansas

    Science.gov (United States)

    1980-01-01

    A solar heating system designed to supply a major portion of the space and water heating requirements for a restaurant is described. The restaurant has a floor space of approximately 4,650 square feet and requires approximate 1500 gallons of hot water daily. The solar energy system consists of 1,428 square feet of Chamberlain flat plate liquid collector subsystem, and a 1500 gallon storage subsystem circulating hot water producing 321 x 10 to the 6th power Btu/Yr (specified) building heating and hot water heating.

  9. Overview of waste heat utilization systems

    Science.gov (United States)

    Bailey, M. M.

    1984-01-01

    The heavy truck diesel engine rejects a significant fraction of its fuel energy in the form of waste heat. Historically, the Department of Energy has supported technology efforts for utilization of the diesel exhaust heat. Specifically, the Turbocompound and the Organic Rankine Cycle System (ORCS) have demonstrated that meaningful improvements in highway fuel economy can be realized through waste heat utilization. For heat recovery from the high temperature exhaust of future adiabatic diesel engines, the DOE/NASA are investigating a variety of alternatives based on the Rankine, Brayton, and Stirling power cycles. Initial screening results indicate that systems of this type offer a fuel savings advantage over the turbocompound system. Capital and maintenance cost projections, however, indicate that the alternative power cycles are not competitive on an economic payback basis. Plans call for continued analysis in an attempt to identify a cost effective configuration with adequate fuel savings potential.

  10. Use of the water supply system of special purpose in buildings

    Directory of Open Access Journals (Sweden)

    Orlov Evgeniy Vladimirovich

    Full Text Available A water supply system of a special purpose is a necessary element in hot and cold shops of the industrial enterprises, office buildings and the medical centers, and also other rooms. The water supply systems of a special purpose, which give subsalty, sparkling water and water sated with oxygen, allow people to prevent, for example, strong dehydration of an organism, which is possible at big losses of water, especially in case of the people working in hot shops. Various elements of special drinking water supply system are given in the article, their main functions are described. Different types of the water folding devices pumping water to consumers, one of which is drinking fountain, are considered. Possible systems of water filtration, which can be established for quality improvement, are transferred. Among them the great role is played by membrane technologies and the return osmosis, which is widely applied now. Today there is a possibility of construction, both the centralized water supply system of a special purpose, and local. Besides, the least is a more preferable option taking into account capital expenditure for construction and operation, and also it can lead to solid resource-saving as a result of the electric energy saving going for water heating in heaters. Automatic machines of drinking water for a local water supply system of a special purpose have indisputable advantages. They are capable to carry out several functions at the same time, and also to distribute water to consumers. It allows placing all the necessary equipment, which will be well in harmony with the environment in their small and compact case, and will fit into any difficult interior of the room. Also they are very easily connected to the systems of an internal water supply system by means of a propylene tube that allows to change their sposition in space and to transfer to any place of the room with fast installation of equipment. Also the ecological effect was

  11. A Direct Heat Exchanger Unit used for Domestic Hot Water Supply in a Single-family House Supplied by Low Energy District Heating

    DEFF Research Database (Denmark)

    Brand, Marek; Thorsen, Jan Eric; Svendsen, Svend

    2010-01-01

    and 47 °C when the tap is opened. Measurements were made for control strategies using internal and external by-pass and no by-pass. Our results show the importance of keeping the branch pipe warm if comfort requirements are to be fulfilled, but this involves higher user costs for heating. To increase...

  12. Residential solar-heating system - design brochure

    Science.gov (United States)

    1978-01-01

    Design brochure for commercially-available solar-heating system is valuable to architects, engineers, and designers. It contains information on system configuration, system sizing, and mechanical layout. Drawings and specifications of all components and typical installation details are included in appendix.

  13. Prototype solar heating and cooling systems

    Energy Technology Data Exchange (ETDEWEB)

    1978-03-01

    A collection of quarterly reports from the AiResearch Manufacturing Company covering the period July 12, 1976, through December 31, 1977, is presented. AiResearch Manufacturing Company is developing eight prototype solar heating and cooling systems. This effort calls for the development, manufacture, test, system installation, maintenance, problem resolution, and performance evaluation. The systems are 3, 25 and 75-ton size units.

  14. Development of a Portfolio Simulation System for Apparel Supply Chain

    Institute of Scientific and Technical Information of China (English)

    DONG Ai-hua; WONG Wai-keung; YEUNG Kwok-wing; CHAN Sek-foo

    2009-01-01

    In this paper, a generic retailer-oriented portfolio simulation system linking manufacturer, retailer, and customer in apparel supply chain is presented. The purpose of the simulator is to generate a portfolio consisting of replenishment strategy and performance index under different sales forecasting errors to satisfy the retailerdefined customer service level in apparel industry. After analyzing the main parameters in the portfolio simulator,the procedure and detailed structure of the simulator are then described. With the use of data from the industry, one case study of the portfolio simulator is achieved and the process of the simulation is validated.

  15. Fuel Costs, Propulsion Systems and Interplanetary Supply Chains

    Science.gov (United States)

    Smith, R.

    A perspective on the economics of space logistics in a future state where there are continuous supply routes between Earth and outlying bodies in the solar system is discussed. In particular, the dependence of the cost of transport on specific impulse and % of non-fuel mass as cargo is discussed. Also, a simple way to calculate the optimal cargo mass of a transport ship carrying a commodity with constant demand is proposed as well as qualitative issues regarding backhaul and inventory that space logistics planners will have to one day confront.

  16. Motivation System of Crowdsourcing Community from a Supply Chain Perspective

    Directory of Open Access Journals (Sweden)

    Jiangang Pang

    2016-01-01

    Full Text Available This paper uses principal-agent theory to study the issue of incentivizing crowdsourcing communities. It proves that enterprises can generate innovation plans of high quality and expected utility using the crowdsourcing community. Outsourcers can encourage high-quality people to join by adopting a linear variable compensation scheme and make the low-quality people quit by requiring them to supply more effort. The paper also shows that enterprises’ participation in crowdsourcing community innovation can effectively improve their innovative ability and that it is necessary for enterprises to construct an effective and cooperative innovative system combining crowdsourcing community innovation and their own internal innovation.

  17. Hydrogen and renewable energy sources integrated system for greenhouse heating

    Directory of Open Access Journals (Sweden)

    Ileana Blanco

    2013-09-01

    Full Text Available A research is under development at the Department of Agro- Environmental Sciences of the University of Bari “Aldo Moro” in order to investigate the suitable solutions of a power system based on solar energy (photovoltaic and hydrogen, integrated with a geothermal heat pump for powering a self sustained heated greenhouse. The electrical energy for heat pump operation is provided by a purpose-built array of solar photovoltaic modules, which supplies also a water electrolyser system controlled by embedded pc; the generated dry hydrogen gas is conserved in suitable pressured storage tank. The hydrogen is used to produce electricity in a fuel cell in order to meet the above mentioned heat pump power demand when the photovoltaic system is inactive during winter night-time or the solar radiation level is insufficient to meet the electrical demand. The present work reports some theoretical and observed data about the electrolyzer operation. Indeed the electrolyzer has required particular attention because during the experimental tests it did not show a stable operation and it was registered a performance not properly consistent with the predicted performance by means of the theoretical study.

  18. Design for micro-combined cooling, heating and power systems stirling engines and renewable power systems

    CERN Document Server

    2015-01-01

    ‘Design for Micro-Combined Cooling, Heating & Power Systems’ provides a manual for the technical and structural design of systems for supplying decentralised energy in residential buildings. It presents the micro-combined cooling, heating & power systems Stirling engines & renewable energy sources (mCCHP-SE-RES) systems in an accessible manner both for the public at large, and for professionals who conceive, design or commercialise such systems or their components.  The high performance levels of these systems are demonstrated within the final chapter by the results of an experiment in which a house is equipped with a mCCHP-SE-RES system. The reader is also familiarized with the conceptual, technical and legal aspects of modern domestic energy systems; the components that constitute these systems; and advanced algorithms for achieving the structural and technical design of such systems. In residential buildings, satisfying demands of durable development has gradually evolved from necessity to...

  19. INVESTIGATION OF THE KINETICS OF THE MIXING PROCESS AT VARIABLE SPREADS HEAT SUPPLY

    Directory of Open Access Journals (Sweden)

    A. N. Ostrikov

    2015-01-01

    Full Text Available The investigation of the kinetics of mixing creamy vegetable spreads with a variable heat supply. The time of each of the periods of re-mixing. Stirring at a temperature of 65 °C optimum convective mixing period was 2.5 minutes. Convective mixing duration after the beginning of crystallization of the product (i.e., by stirring at a temperature of 30 ... 15 ° C was 5 minutes. The second period at a temperature of 65 ° C was 2.2 min. Mixing diffusion time during 9 minutes to crystallize the product. The entire mixing process was conditionally divided into three temperature-time periods: 1 a period of intense agitation; 2 during product cooling to a crystallization temperature; 3 the product during crystallization. The investigations of the process at different speeds working body were to choose the best, to get good distribution of all components in the minimum time. The result was that the spread manufactured according to the proposed formulation meets the optimal mixing time stirrer speed is 150 rev / min (during intensive stirring, 10 rev / min (during cooling of the product to a crystallization temperature and 15 rev / min during crystallization. The optimal mixing time using the dependence of the dimensionless concentration of a key component of the mixing time. The result was the optimum time for process spread 4.7 min at 65 ° C. Conducted research to determine the optimal mixing time in the crystallization of the product, it was 14 minutes. The increase in the mixing time required for uniform distribution of components in the mixture in small quantities.

  20. Local planning of electricity supply systems; Lokal kraftsystemplanlegging

    Energy Technology Data Exchange (ETDEWEB)

    Egeland, H.; Otnes, H.

    1995-01-25

    This publication discusses the planning of electricity supply systems in the Norwegian distribution networks and the legal basis and supply quality. It also describes the realization of the planning work and the design of the power system plan. The authorities expect that, prior to the construction of new distribution plants, the local concessionaire will perform an analysis of the needs and see this in connection with the other plants, with rehabilitations and alternative upgrades. To meet this objective an overview should be worked out of the transfer system in the region along with a plan for the coming network investments. Regional concessionaires who do not have such plans are therefore recommended to make them as soon as possible. Plans will be required as needed. The plan must be vertically coordinated with the main distribution network or regional network and horizontally with the neighbouring networks. A plan will be an important basis for the energy company`s strategic plans and a tool for efficient exploitation of its resources. 1 figure

  1. Modeling and simulation of combined gas turbine engine and heat pipe system for waste heat recovery and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Lamfon, N.J. [Saudi Aramco Jeddah Refinery, Jeddah (Saudi Arabia); Najjar, Y.S.H.; Akyurt, M. [King Abdulaziz Univ., Mechanical Engineering Dept., Jeddah (Saudi Arabia)

    1998-12-01

    The results of a modeling and simulation study are presented for a combined system consisting of a gas turbine engine, a heat pipe recovery system and an inlet-air cooling system. The presentation covers performance data related to the gas turbine engine with precooled air intake as coupled to the water-in-copper heat pipe recovery system. This is done by matching the two mathematical models. The net power output is improved by 11% when the gas turbine engine is supplied with cold air produced by the heat-pipe recovery and utilization system. It is further concluded from the results produced by the combined mathematical model that the thermal efficiency of the gas turbine engine rises to 6% at 75% part load. It is to be anticipated that this rising trend in increases of thermal efficiency of the gas turbine engine would continue for operations at other (lower) part load conditions. (author)

  2. Control and prevention of ice formation and accretion on heat exchangers for ventilation systems

    DEFF Research Database (Denmark)

    Rahimi, Maral; Afshari, Alireza

    2015-01-01

    In cold climates, the application of mechanical ventilation systems with heat recovery like are airto-air exchangers is used for reducing energy consumption for heating buildings by transferring heat exhausted air to supply air. However, increase efficiency of heat exchanger results in lower...... exhaust air temperatures and Ice formation on heat exchanger fins, which can cause problem and is not favourable. Therefore, prevention and control of ice formation on heat exchangers is necessary. The existing methods are divided into two different methods: active and passive ice control methods....... The active methods are e.g. bypass, recirculation, preheating. The passive methods relate to the surface characteristics of the heat exchanger fins as they have effect on ice formation in initial phase. All these methods have varying levels of success, cost, and effectiveness, which are depending on the heat...

  3. Solar Powered Heat Control System for Cars

    Directory of Open Access Journals (Sweden)

    Abin John

    2014-05-01

    Full Text Available It takes times for an air-conditioner to effectively start cooling the passenger compartment in the car. So the passenger of the car will feel the heat in the car extremely before the air-conditioner fully cooling the interior of the car. Excessive heat can also damage an automobile's interior as well as personal property kept in the passenger compartment. So, a system to reduce this excessive heat by pumping out hot air and allowing cooler ambient air to enter the car by means of two micro fans was made. Also a cooling chamber was set up around the inlet fan to cool it a little further.

  4. Carbon nanotube heat-exchange systems

    Science.gov (United States)

    Hendricks, Terry Joseph; Heben, Michael J.

    2008-11-11

    A carbon nanotube heat-exchange system (10) and method for producing the same. One embodiment of the carbon nanotube heat-exchange system (10) comprises a microchannel structure (24) having an inlet end (30) and an outlet end (32), the inlet end (30) providing a cooling fluid into the microchannel structure (24) and the outlet end (32) discharging the cooling fluid from the microchannel structure (24). At least one flow path (28) is defined in the microchannel structure (24), fluidically connecting the inlet end (30) to the outlet end (32) of the microchannel structure (24). A carbon nanotube structure (26) is provided in thermal contact with the microchannel structure (24), the carbon nanotube structure (26) receiving heat from the cooling fluid in the microchannel structure (24) and dissipating the heat into an external medium (19).

  5. Study on performance of a packed bed latent heat thermal energy storage unit integrated with solar water heating system

    Institute of Scientific and Technical Information of China (English)

    NALLUSAMY N.; SAMPATH S.; VELRAJ R.

    2006-01-01

    In thermal systems such as solar thermal and waste heat recovery systems, the available energy supply does not usually coincide in time with the process demand. Hence some form of thermal energy storage (TES) is necessary for the most effective utilization of the energy source. This study deals with the experimental evaluation of thermal performance of a packed bed latent heat TES unit integrated with solar flat plate collector. The TES unit contains paraffin as phase change material (PCM) filled in spherical capsules, which are packed in an insulated cylindrical storage tank. The water used as heat transfer fluid (HTF) to transfer heat from the solar collector to the storage tank also acts as sensible heat storage material. Charging experiments were carried out at varying inlet fluid temperatures to examine the effects of porosity and HTF flow rate on the storage unit performance. The performance parameters such as instantaneous heat stored, cumulative heat stored, charging rate and system efficiency are studied.Discharging experiments were carried out by both continuous and batchwise processes to recover the stored heat, and the results are presented.

  6. 46 CFR 154.178 - Contiguous hull structure: Heating system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous hull structure: Heating system. 154.178... Equipment Hull Structure § 154.178 Contiguous hull structure: Heating system. The heating system for... the heating capacity to meet § 154.174(b)(2) or § 154.176(b)(2); (b) Have stand-by heating to...

  7. Thermal energy storage system using phase change materials: Constant heat source

    Directory of Open Access Journals (Sweden)

    Reddy Meenakshi R.

    2012-01-01

    Full Text Available The usage of phase change materials (PCM to store the heat in the form of latent heat is increased, because large quantity of thermal energy is stored in smaller volumes. In the present experimental investigation paraffin and stearic acid are employed as PCMs in thermal energy storage (TES system to store the heat as sensible and latent heat also. A constant heat source is used to supply heat transfer fluid (HTF at constant temperature to the TES system. In the TES system PCMs are stored in the form of spherical capsules of 38 mm diameter made of high density poly ethylene (HDPE. The results of the investigation are related to the charging time and recovery of stored energy from the TES system.

  8. Design and Fabrication of Power Supply to Heat the Titanium Ball in Vacuum Chamber of HL-2A Tokamak

    Institute of Scientific and Technical Information of China (English)

    KANGZhihua; RAOJun; ZHOUJun; WANGMingwei; CHENGanyu; ZHANGJingsong

    2003-01-01

    By using the physical characteristic of the titanium when it is subliming, fourteen titanium balls are fixed in the vacuum chamber to improve the background of the wall of the vacuum chamber of HL-2A. When the filaments of the balls have 40- 50 A current,temperatures of the balls is up to 1200 centigrade and the balls begin to sublime. Therefore in order to get better parameters of plasma, we fabricate fourteen power supplies to heat the balls.

  9. Impact of enhanced geothermal systems on US energy supply in the twenty-first century.

    Science.gov (United States)

    Tester, Jefferson W; Anderson, Brian J; Batchelor, Anthony S; Blackwell, David D; DiPippo, Ronald; Drake, Elisabeth M; Garnish, John; Livesay, Bill; Moore, Michal C; Nichols, Kenneth; Petty, Susan; Toksoz, M Nafi; Veatch, Ralph W; Baria, Roy; Augustine, Chad; Murphy, Enda; Negraru, Petru; Richards, Maria

    2007-04-15

    Recent national focus on the value of increasing US supplies of indigenous renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well distributed nationally. A panel was assembled in September 2005 to evaluate the technical and economic feasibility of geothermal becoming a major supplier of primary energy for US base-load generation capacity by 2050. Primary energy produced from both conventional hydrothermal and enhanced (or engineered) geothermal systems (EGS) was considered on a national scale. This paper summarizes the work of the panel which appears in complete form in a 2006 MIT report, 'The future of geothermal energy' parts 1 and 2. In the analysis, a comprehensive national assessment of US geothermal resources, evaluation of drilling and reservoir technologies and economic modelling was carried out. The methodologies employed to estimate geologic heat flow for a range of geothermal resources were utilized to provide detailed quantitative projections of the EGS resource base for the USA. Thirty years of field testing worldwide was evaluated to identify the remaining technology needs with respect to drilling and completing wells, stimulating EGS reservoirs and converting geothermal heat to electricity in surface power and energy recovery systems. Economic modelling was used to develop long-term projections of EGS in the USA for supplying electricity and thermal energy. Sensitivities to capital costs for drilling, stimulation and power plant construction, and financial factors, learning curve estimates, and uncertainties and risks were considered.

  10. Flood risk assessment of fresh water supply systems

    Science.gov (United States)

    Arrighi, Chiara; Tarani, Fabio; Vicario, Enrico; Castelli, Fabio

    2017-04-01

    Flooding is a common hazard causing damages to people, buildings and infrastructures. Often located in low-lying areas or nearby rivers, water utilities are particularly vulnerable to flooding. Water and debris can inundate the facility, thereby damaging equipment and causing power outages. Such impacts can lead to costly repairs, disruptions of service, hazardous situations for personnel and public health advisories. While flood damage evaluation to buildings and their contents is becoming increasingly available, the quantification of impact on critical infrastructures is less common. In this work, we present the flood risk assessment of a fresh water supply system considering the hazard of a riverine flooding and exposure and vulnerability of the system components (i.e. pipes, junctions, lifting stations etc.). The evaluation of flood impact on the aqueduct network is carried out for flood scenarios with assigned recurrence intervals. Vulnerable elements exposed to the flood are identified and analysed in order to determine their residual functionality. Above a selected threshold, the affected elements are considered as failed. The water distribution piping system is modelled through a model based on EPANET designed so as to implement Pressure-Driven Demand (PDD), which is more appropriate when modelling water distribution networks with a high number of offline nodes. Results of piping system model affected by the flood are then compared in a QGIS environment with flood depth to identify the location of service outages and potential risk of contamination. The application to the water supply system of the city of Florence (Italy), serving approximately 385000 inhabitants through 900 km of piping is presented and discussed.

  11. Competitive solar heating systems for residential buildings

    DEFF Research Database (Denmark)

    Furbo, Simon; Thür, Alexander; Fiedler, Frank

    2005-01-01

    The paper describes the ongoing research project “Competitive solar heating systems for residential buildings”. The aim of the project is to develop competitive solar combisystems which are attractive to buyers. The solar combisystems must be attractive compared to traditional energy systems, both....... In Denmark and Norway the focus is on solar heating/natural gas systems, and in Sweden and Latvia the focus is on solar heating/pellet systems. Additionally, Lund Institute of Technology and University of Oslo are studying solar collectors of various types being integrated into the roof and facade......, are the universities: Technical University of Denmark, Dalarna University, University of Oslo, Riga Technical University and Lund Institute of Technology, as well as the companies: Metro Therm A/S (Denmark), Velux A/S (Denmark), Solentek AB (Sweden) and SolarNor (Norway). The project consists of a number of Ph...

  12. Optimising corrosion monitoring in district heating systems

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel; Thorarinsdottir, R.I.; Andersen, A.

    2002-01-01

    is to improve the quality control in district heating systems by corrosion monitoring. In Danish systems electrochemical impedance spectroscopy (EIS), linear polarisation resistance (LPR), high-sensitive electrical resistance (ER) technology, crevice corrosion probes, as well as weight loss coupons......A three-year project - financially supported by the Nordic Industrial Fund - on monitoring of corrosion in district heating systems has been initiated with participation of researchers and industrial partners in Denmark, Finland, Iceland, Norway and Sweden. The primary objective of the project...... will be tested. Laboratory studies as well as on-line measurements in district heating systems using probes in a specially designed sidestream unit are included in the practical part of the project....

  13. Demand modelling for central heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Heller, A.

    2000-07-01

    Most researchers in the field of heat demand estimation have focussed on explaning the load for a given plant based on rather few measurements. This approach is simply the only one adaptable with the very limited data material and limited computer power. This way of dealing with the subject is here called the top-down approach, due to the fact that one tries to explain the load from the overall data. The results of such efforts are discussed in the report, leading to inspiration for own work. Also the significance of the findings to the causes for given heat loads are discussed and summarised. Contrary to the top-down approach applied in literature, a here-called bottom-up approach is applied in this work, describing the causes of a given partial load in detail and combining them to explain the total load for the system. Three partial load 'components' are discussed: 1) Space heating. 2) Hot-Water Consumption. 3) Heat losses in pipe networks. The report is aimed at giving an introduction to these subjects, but at the same time at collecting the previous work done by the author. Space heating is shortly discussed and loads are generated by an advanced simulation model. A hot water consumption model is presented and heat loads, generated by this model, utilised in the overall work. Heat loads due to heat losses in district heating a given a high priority in the current work. Hence a detailed presentation and overview of the subject is given to solar heating experts normally not dealing with district heating. Based on the 'partial' loads generated by the above-mentioned method, an overall load model is built in the computer simulation environment TRNSYS. The final tool is then employed for the generation of time series for heat demand, representing a district heating area. The results are compared to alternative methods for the generation of heat demand profiles. Results form this comparison will be presented. Computerised modelling of systems

  14. Heat transfer analysis of underground U-type heat exchanger of ground source heat pump system.

    Science.gov (United States)

    Pei, Guihong; Zhang, Liyin

    2016-01-01

    Ground source heat pumps is a building energy conservation technique. The underground buried pipe heat exchanging system of a ground source heat pump (GSHP) is the basis for the normal operation of an entire heat pump system. Computational-fluid-dynamics (CFD) numerical simulation software, ANSYS-FLUENT17.0 have been performed the calculations under the working conditions of a continuous and intermittent operation over 7 days on a GSHP with a single-well, single-U and double-U heat exchanger and the impact of single-U and double-U buried heat pipes on the surrounding rock-soil temperature field and the impact of intermittent operation and continuous operation on the outlet water temperature. The influence on the rock-soil temperature is approximately 13 % higher for the double-U heat exchanger than that of the single-U heat exchanger. The extracted energy of the intermittent operation is 36.44 kw·h higher than that of the continuous mode, although the running time is lower than that of continuous mode, over the course of 7 days. The thermal interference loss and quantity of heat exchanged for unit well depths at steady-state condition of 2.5 De, 3 De, 4 De, 4.5 De, 5 De, 5.5 De and 6 De of sidetube spacing are detailed in this work. The simulation results of seven working conditions are compared. It is recommended that the side-tube spacing of double-U underground pipes shall be greater than or equal to five times of outer diameter (borehole diameter: 180 mm).

  15. Heat Driven Cooling in District Energy Systems; Vaermedriven Kyla

    Energy Technology Data Exchange (ETDEWEB)

    Rydstrand, Magnus; Martin, Viktoria; Westermark, Mats [Royal Inst. of Technology, Stockholm (Sweden). Dept. of Chemical Engineering and Technology

    2004-07-01

    This report is reviewing different heat driven technologies for the production of cooling. It is shown that the supply of cooling gives the highest fuel utilization if heat from CHP production is used for the production of cooling instead of maximizing the electricity output in a condensing plant. High fuel utilization is reached since the direct production of cooling from heat is a thermodynamic shortcut as compared to the production of electricity as an intermediate product before cooling is produced. At direct production of cooling from heat it is possible to obtain 70 percent of the obtainable cooling of an ideal process. If electricity is produced from heat, 70 percent electricity could be obtained as compared to an ideal process. If this electricity would be used for the production of cooling 70 percent of the obtainable cooling in an ideal process would the result. The total production of cooling from heat with electricity as an intermediate product would therefore give 50 percent cooling as compared to an ideal process. Hence, heat driven cooling will give more cooling for a given fuel input. In the review of the different heat driven cooling options it was found that there are many alternatives suitable for different applications. Absorption cooling is suitable for water distributed cooling if the latent cooling load is low. Desiccant cooling is believed to have a large market in climates (applications) with high latent cooling loads. In the energy efficiency evaluation it is found that the highest fuel utilization is given for a central production of electricity using either district heating or district cooling as the energy carrier to supply cooling. In fact the potential of district heating as the energy carrier is thought to be the largest in large cities with humid climates. Further it is found that the chiller heat sink can contribute significantly to the cost in many applications, especially if water and/or electricity consumption are issues with

  16. A hybrid decision support system for iron ore supply

    Directory of Open Access Journals (Sweden)

    A. Samolejová

    2012-01-01

    Full Text Available Many European metallurgical companies are forced to import iron ore from remote destinations. For these companies it is necessary to determine the amount of iron ore that will have to be ordered and to create such a delivery schedule so that the continuous operation of blast-furnace plant is not disrupted and there is no exceedingly large stock of this raw material. The objective of this article is to design the decision support system for iron ore supply which would effi ciently reduce uncertainty and risk of that decision-making. The article proposes a hybrid intelligent system which represents a combination of diff erent artifi cial intelligence methods with dynamic simulation technique for that purpose.

  17. Fuel-cell powered uninterruptible power supply systems: Design considerations

    Science.gov (United States)

    Choi, Woojin; Howze, Jo. W.; Enjeti, Prasad

    A 1-kVA fuel cell powered, line-interactive uninterruptible power supply (UPS) system that employs modular (fuel cell and power converter) blocks is introduced. Two commercially available proton-exchange membrane fuel cell (25-39 V, 500 W) modules together with suitable dc-dc and dc-ac power electronic converter modules are employed. A supercapacitor module is also used to compensate for the instantaneous power fluctuations and to overcome the slow dynamics of the fuel processor (reformers). Further energy stored in the supercapacitor is also utilized to handle a momentary overload such as 200% for a short duration. Due to the absence of batteries, the system satisfies the demand for an environmentally clean source of energy. A complete design that defines the amount of hydrogen storage required for a power outage of 1 h, and the sizing of the supercapacitors for transient load demand is presented for a 1-kVA UPS.

  18. Modeling integrated water user decisions in intermittent supply systems

    Science.gov (United States)

    Rosenberg, David E.; Tarawneh, Tarek; Abdel-Khaleq, Rania; Lund, Jay R.

    2007-07-01

    We apply systems analysis to estimate household water use in an intermittent supply system considering numerous interdependent water user behaviors. Some 39 household actions include conservation; improving local storage or water quality; and accessing sources having variable costs, availabilities, reliabilities, and qualities. A stochastic optimization program with recourse decisions identifies the infrastructure investments and short-term coping actions a customer can adopt to cost-effectively respond to a probability distribution of piped water availability. Monte Carlo simulations show effects for a population of customers. Model calibration reproduces the distribution of billed residential water use in Amman, Jordan. Parametric analyses suggest economic and demand responses to increased availability and alternative pricing. It also suggests potential market penetration for conservation actions, associated water savings, and subsidies to entice further adoption. We discuss new insights to size, target, and finance conservation.

  19. Modeling and analyzing a health care supply chain system

    OpenAIRE

    Al-Thumairi, Ahmed Hamad

    2006-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. A Thesis presented on Improving and Redefining the Supply Chain in Healthcare, defining existing problems with current Supply Chain applications, and reviewing current applications and trends in the Supply Chain culture within the Manufacturing Industries and Healthcare Industries. Research of successful applications of new, and improvements to existing supply chain methodologies are prese...

  20. Nonstationary Heat Conduction in Atomic Systems

    Science.gov (United States)

    Singh, Amit K.

    Understanding heat at the atomistic level is an interesting exercises. It is fascinating to note how the vibration of atoms result into thermodynamic concept of heat. This thesis aims to bring insights into different constitutive laws of heat conduction. We also develop a framework in which the interaction of thermostats to the system can be studied and a well known Kapitza effect can be reduced. The thesis also explores stochastic and continuum methods to model the latent heat release in the first order transition of ideal silicon surfaces into dimers. We divide the thesis into three works which are connected to each other: 1. Fourier's law leads to a diffusive model of heat transfer in which a thermal signal propagates infinitely fast and the only material parameter is the thermal conductivity. In micro- and nano-scale systems, non-Fourier effects involving coupled diffusion and wavelike propagation of heat can become important. An extension of Fourier's law to account for such effects leads to a Jeffreys-type model for heat transfer with two relaxation times. In this thesis, we first propose a new Thermal Parameter Identification (TPI) method for obtaining the Jeffreys-type thermal parameters from molecular dynamics simulations. The TPI method makes use of a nonlinear regression-based approach for obtaining the coefficients in analytical expressions for cosine and sine-weighted averages of temperature and heat flux over the length of the system. The method is applied to argon nanobeams over a range of temperature and system sizes. The results for thermal conductivity are found to be in good agreement with standard Green-Kubo and direct method calculations. The TPI method is more efficient for systems with high diffusivity and has the advantage, that unlike the direct method, it is free from the influence of thermostats. In addition, the method provides the thermal relaxation times for argon. Using the determined parameters, the Jeffreys-type model is able to