Thermodynamic analysis of energy conversion and transfer in hybrid system consisting of wind turbine and advanced adiabatic compressed air energy storage

International Nuclear Information System (INIS)

Zhang, Yuan; Yang, Ke; Li, Xuemei; Xu, Jianzhong

2014-01-01

A simulation model consisting of wind speed, wind turbine and AA-CAES (advanced adiabatic compressed air energy storage) system is developed in this paper, and thermodynamic analysis on energy conversion and transfer in hybrid system is carried out. The impacts of stable wind speed and unstable wind speed on the hybrid system are analyzed and compared from the viewpoint of energy conversion and system efficiency. Besides, energy conversion relationship between wind turbine and AA-CAES system is investigated on the basis of process analysis. The results show that there are several different forms of energy in hybrid system, which have distinct conversion relationship. As to wind turbine, power coefficient determines wind energy utilization efficiency, and in AA-CAES system, it is compressor efficiency that mainly affects energy conversion efficiencies of other components. The strength and fluctuation of wind speed have a direct impact on energy conversion efficiencies of components of hybrid system, and within proper wind speed scope, the maximum of system efficiency could be expected. - Highlights: • A hybrid system consisting of wind, wind turbine and AA-CAES system is established. • Energy conversion in hybrid system with stable and unstable wind speed is analyzed. • Maximum efficiency of hybrid system can be reached within proper wind speed scope. • Thermal energy change in hybrid system is more sensitive to wind speed change. • Compressor efficiency can affect other efficiencies in AA-CAES system

Economic perspective of hybrid wind-diesel technology for commercial loads of Dhahran Saudi Arabia: A step towards sustainable future

Directory of Open Access Journals (Sweden)

Shaahid S.M.

2015-01-01

Full Text Available The governments world-wide are deliberating to promote renewable energy sources such as wind to mitigate increasing demand of energy and to overcome effects of pollution due to to use of fossil fuels. Integration of wind turbine generators (WTG with the diesel plants is pursued widely to reduce dependence on fossil-fuels and to reduce carbon emissions. Literature indicates that commercial/residential buildings in the Kingdom of Saudi Arabia (K.S.A consume an estimated 10 - 40% of the total electric energy generated. The aim of this study is to analyze wind-speed data of Dhahran (East-Coast, K.S.A. to assess the economic feasibility of utilizing hybrid wind-diesel power systems to meet the load requirements of a typical commercial building (with annual electrical energy demand of 620,000 kWh. The monthly average wind speeds range from 3.3 to 5.6 m/s. The hybrid systems simulated consist of different combinations of 100 kW commercial WTG supplemented with diesel generators. NREL’s (HOMER Energy’s HOMER software has been employed to perform the techno-economic analysis. The simulation results indicate that for a hybrid system comprising of 100 kW wind capacity together with 175 kW diesel system, the wind penetration (at 37 m hub-height, with 0% annual capacity shortage is 25%. The cost of generating energy (COE, $/kWh from this hybrid wind-diesel system has been found to be 0.121 $/kWh (assuming diesel fuel price of 0.1$/liter. The study exhibits that for a given hybrid configuration, the number of operational hours of diesel gensets decreases with increase in wind farm capacity. Emphasis has also been placed on wind penetration, un-met load, energy production and COE, excess electricity generation, percentage fuel savings and reduction in carbon emissions (relative to diesel-only situation of different hybrid systems, cost break-down of wind-diesel systems, COE of different hybrid systems, etc.

Techno-economic Analysis of a Wind-Diesel Hybrid Power System in the South Algeria

Directory of Open Access Journals (Sweden)

Khaireddine Allali

2015-07-01

Full Text Available The electrical energy is often produced with the help of diesel generators in isolated areas in the Saharan region. While the latter requiring relatively little investment because is generally expensive to exploit due to the transportation to remote areas adds extra cost, significant fuel consumption and relatively high maintenance cost, etc. Moreover, the electricity production by the diesel is ineffective, presents significant environmental risks. But these isolated areas have significant wind energy potential; which is good position for the exploitation of clean and sustainable wind energy. The use of wind-diesel power system is widely recommended especially to reduce fuel consumption and in this way to reduce system operating costs and environmental impact. The subject of this paper is to present the techno-economic analysis of a wind-diesel hybrid power system. In this context, the contribution envisaged with this research is to collaborate on the optimal design of a hybrid power system including a wind turbine generator, a diesel generator and an energy storage system for powering a continuous way an isolated site in the South Algerian installed power of 120 kW.This system has a high control strategy for the management of different power sources (wind, diesel, battery that depending to weather conditions, especially wind speed values and the power demanded by the consumer load.

Worldwide wind/diesel hybrid power system study: Potential applications and technical issues

Energy Technology Data Exchange (ETDEWEB)

King, W.R.; Johnson, B.L. III (Science Applications International Corp., McLean, VA (USA))

1991-04-01

The world market potential for wind/diesel hybrid technology is a function of the need for electric power, the availability of sufficient wind resource to support wind/diesel power, and the existence of buyers with the financial means to invest in the technology. This study includes data related to each of these three factors. This study does not address market penetration, which would require analysis of application specific wind/diesel economics. Buyer purchase criteria, which are vital to assessing market penetration, are discussed only generally. Countries were screened for a country-specific market analysis based on indicators of need and wind resource. Both developed countries and less developed countries'' (LDCs) were screened for wind/diesel market potential. Based on the results of the screening, ten countries showing high market potential were selected for more extensive market analyses. These analyses provide country-specific market data to guide wind/diesel technology developers in making design decisions that will lead to a competitive product. Section 4 presents the country-specific data developed for these analyses, including more extensive wind resource characterization, application-specific market opportunities, business conditions, and energy market characterizations. An attempt was made to identify the potential buyers with ability to pay for wind/diesel technology required to meet the application-specific market opportunities identified for each country. Additionally, the country-specific data are extended to corollary opportunities in countries not covered by the study. Section 2 gives recommendations for wind/diesel research based on the findings of the study. 86 refs.

Worldwide wind/diesel hybrid power system study: Potential applications and technical issues

Science.gov (United States)

King, W. R.; Johnson, B. L., III

1991-04-01

The world market potential for wind/diesel hybrid technology is a function of the need for electric power, the availability of sufficient wind resource to support wind/diesel power, and the existence of buyers with the financial means to invest in the technology. This study includes data related to each of these three factors. This study does not address market penetration, which would require analysis of application specific wind/diesel economics. Buyer purchase criteria, which are vital to assessing market penetration, are discussed only generally. Countries were screened for a country-specific market analysis based on indicators of need and wind resource. Both developed countries and less developed countries (LDCs) were screened for wind/diesel market potential. Based on the results of the screening, ten countries showing high market potential were selected for more extensive market analyses. These analyses provide country-specific market data to guide wind/diesel technology developers in making design decisions that will lead to a competitive product. Section 4 presents the country-specific data developed for these analyses, including more extensive wind resource characterization, application-specific market opportunities, business conditions, and energy market characterizations. An attempt was made to identify the potential buyers with ability to pay for wind/diesel technology required to meet the application-specific market opportunities identified for each country. Additionally, the country-specific data are extended to corollary opportunities in countries not covered by the study. Section 2 gives recommendations for wind/diesel research based on the findings of the study.

Economic and technical study of a hybrid system (wind-photovoltaic-diesel) for rural electrification in Algeria

Energy Technology Data Exchange (ETDEWEB)

Saheb-Koussa, D.; Belhamel, M. [Centre of Development of Renewable energies, Route de l' observatoire, BP.62 Bouzareah, Algiers (Algeria); Haddadi, M. [Laboratoire de Dispositif de Communication et de Conversion Photovoltaique E. N. P, 10 Avenue Hassen Badi, El Harrach, Alger (Algeria)

2009-07-15

This paper deals with design of hybrid energy system consisting of wind and photovoltaic with battery storage. A diesel generator is added to ensure continuous power supply and to take care of intermittent nature of wind and photovoltaic. The paper reports results of the technical-economic optimization study of photovoltaic/wind/diesel hybrid with battery storage in Algeria. The primary objective of this study is to estimate the appropriate dimension of stand-alone hybrid photovoltaic/wind/diesel with battery storage that guarantee the energy autonomy of typical remote consumer with lowest cost of energy. A secondary aim is to study the impact of renewable energy potential quality on the system size. The optimum dimensions of the system are defined for six sites in Algeria. In this context, a complete sizing model is developed in Matlab/Simulink V.6.5, able to predict the optimum system configuration. The simulation results indicate that the hybrid system is the best option for all the sites considered in this study. Thus, it provides higher system performance than photovoltaic or wind alone. It s shown that the principal advantage of photovoltaic/wind/diesel hybrid with battery storage are used all together, the reliability of the system is enhanced. The economic analysis has resulted in the calculation of kWh cost of energy for different types of resources and optimized cost of hybrid energy system. It s revealed too that the energy cost depends largely on the renewable energy potential quality. So, our objective for the optimization parameters is not the production cost but the offered service. (author)

Optimisation Sizing of Hybrid Wind-Diesel Systems using Linear Programming Technique

OpenAIRE

Gan, Leong Kit; Shek, Jonathan; Mueller, Markus

2014-01-01

Despite the great potential of hybrid wind-diesel system in supplying energy to remote or island communities, sizing the system components have been a challenging problem for many project managers due to the reliance on various factors. This work considers utilising a fixed speed wind turbine (induction generator) in the hybrid system. It requires energy for start-up operation and this work takes into account for sizing the battery storage. In addition, the trade-off between the number of bat...

Design and evaluation of hybrid wind/PV/diesel power systems for Brazilian applications

Energy Technology Data Exchange (ETDEWEB)

McGowan, J.G.; Manwell, J.F.; Avelar, C. [Univ. of Massachusetts, Amherst, MA (United States); Warner, C. [National Renewable Energy Lab., Golden, CO (United States)

1996-12-31

This paper presents a summary of a study centered on the design and evaluation of hybrid wind/PV/diesel systems for remote locations in Brazil. The objective of this work was to evaluate high reliability hybrid power systems that have been designed for the lowest life cycle costs. The technical and economic analysis of the hybrid wind/PV/diesel systems was carried out using HYBRID2, a computational code developed at the University of Massachusetts in conjunction with the National Renewable Energy Laboratory (NREL). After a summary of a generalized design procedure for such systems based on the use of this code, a systematic parametric evaluation of a representative design case for a village power system in Brazil is presented. As summarized in the paper, the performance and economic effects of key design parameters are illustrated. 8 refs., 10 figs.

Decentralized/stand-alone hybrid Wind-Diesel power systems to meet residential loads of hot coastal regions

International Nuclear Information System (INIS)

Elhadidy, M.A.; Shaahid, S.M.

2005-01-01

In view of rising costs, pollution and fears of exhaustion of oil and coal, governments around the world are encouraging to seek energy from renewable/sustainable energy sources such as wind. The utilization of energy from wind (since the oil embargo of the 1970s) is being widely disseminated for displacement of fossil fuel produced energy and to reduce atmospheric degradation. A system that consists of a wind turbine and Diesel genset is called a Wind-Diesel power system.The literature indicates that the commercial/residential buildings in Saudi Arabia consume an estimated 10-40% of the total electric energy generated. In the present study, the hourly mean wind-speed data of the period 1986-1997 recorded at the solar radiation and meteorological station, Dhahran (26 deg. 32'N, 50 deg. 13'E in the Eastern Coastal Region of Saudi Arabia), has been analyzed to investigate the potential of utilizing hybrid (Wind-Diesel) energy conversion systems to meet the load requirements of a hundred typical two bedroom residential buildings (with annual electrical energy demand of 3512 MWh). The long term monthly average wind speeds for Dhahran range from 4.2 to 6.4 m/s. The hybrid systems considered in the present case study consist of different combinations/clusters of 150 kW commercial wind machines supplemented with battery storage and Diesel back-up. The deficit energy generated by the Diesel generator (for different battery capacities) and the number of operational hours of the Diesel system to meet a specific annual electrical energy demand of 3512 MWh have also been presented. The evaluation of the hybrid system shows that with seven 150 kW wind energy conversion system (WECS) and one day of battery storage, the Diesel back-up system has to provide 21.6% of the load demand. Furthermore, with three days of battery storage, the Diesel back-up system has to provide 17.5% of the load demand. However, in the absence of battery storage, about 37% of the load needs to be

A Novel Hybrid-Fuel Storage System of Compressed Air Energy for China

Directory of Open Access Journals (Sweden)

Wenyi Liu

2014-08-01

Full Text Available Compressed air energy storage (CAES is a large-scale technology that provides long-duration energy storage. It is promising for balancing the large-scale penetration of intermittent and dispersed sources of power, such as wind and solar power, into electric grids. The existing CAES plants utilize natural gas (NG as fuel. However, China is rich in coal but is deficient in NG; therefore, a hybrid-fuel CAES is proposed and analyzed in this study. Based on the existing CAES plants, the hybrid-fuel CAES incorporates an external combustion heater into the power generation subsystem to heat the air from the recuperator and the air from the high-pressure air turbine. Coal is the fuel for the external combustion heater. The overall efficiency and exergy efficiency of the hybrid-fuel CAES are 61.18% and 59.84%, respectively. Given the same parameters, the cost of electricity (COE of the hybrid-fuel CAES, which requires less NG, is $5.48/MW∙h less than that of the gas-fuel CAES. Although the proposed CAES requires a relatively high investment in the current electricity system in North China, the proposed CAES will be likely to become competitive in the market, provided that the energy supplies are improved and the large scale grid-connection of wind power is realized.

A concept of wind-diesel hybrid systems for the electrification of small rural communities in Brazil

Energy Technology Data Exchange (ETDEWEB)

Pinho, J.T.; Bezerra, U.H. [Ag. Nucleo Universitario, Para (Brazil)

1997-12-31

This work presents the concept of a wind-diesel hybrid system for the electrification of a small rural community in the Northern Region of Brazil, which can be used in many other places with similar characteristics. The system consists of two small diesel units and two wind turbines, one of which was designed and developed as a prototype with the purpose of gaining some insight in the field of wind turbine technology. Some considerations about small communities of the Northern Region of Brazil, and about electrification concepts are also made.

Generation of electric power through wind-diesel hybrid system for a hospital; Geracao de energia eletrica atraves de sistema hibrido diesel-eolico para um hospital

Energy Technology Data Exchange (ETDEWEB)

Almeida, Silvio Carlos Anibal de; Freire, Raphael Lopes [Universidade Federal do Rio de Janeiro (DEM/UFRJ), RJ (Brazil). Dept. de Engenharia Mecanica], e-mail: silvioa@gmail.com, e-mail: raphaellfreire@gmail.com

2008-07-01

This paper presents a wind-diesel hybrid power simulation using the software Homer. The model is applied to the case study of Hospital das Clinicas da UNICAMP Analysis of several alternative energy facilities like wind, photovoltaic (PV), and connection of the isolated system with the grid is done. The costs used in the simulation indicated that the best results were obtained with the wind-diesel system. The payback period for the investment in the system is 8 years. (author)

Design of a compressed air energy storage system for hydrostatic wind turbines

Directory of Open Access Journals (Sweden)

Ammar E. Ali

2018-03-01

Full Text Available Integration of Compressed Air Energy Storage (CAES system with a wind turbine is critical in optimally harvesting wind energy given the fluctuating nature of power demands. Here we consider the design of a CAES for a wind turbine with hydrostatic powertrain. The design parameters of the CAES are determined based on simulation of the integrated system model for a combination of these parameter values, namely the compression ratios of the air compressors and the expanders and the air tank size. The results of the simulations were used to choose the best design parameters, which would produce the best stable performance through increased energy output of the integrated CAES and wind turbine based on the intermittent wind profile. Simulation results for a 600 kW rated power wind turbine with integrated CAES indicate that increasing the tank size and compression ratio will improve the overall power quality through increased energy output up to a limit beyond which the power quality exhibits only marginal improvement.

Status and modeling improvements of hybrid wind/PV/diesel power systems for Brazilian applications

Energy Technology Data Exchange (ETDEWEB)

McGowan, J.G.; Manwell, J.F.; Avelar, C. [Univ. of Massachusetts, Amherst, MA (United States); Taylor, R. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-31

This paper present a summary of the ongoing work on the modeling and system design of hybrid wind/PV/diesel systems for two different sites in the Amazonia region of Brazil. The work incorporates the latest resource data and is based on the use of the Hybrid2 simulation code developed by the University of Massachusetts and NREL. Details of the baseline operating hybrid systems are reviewed, and the results of the latest detailed hybrid system evaluation for each site are summarized. Based on the system modeling results, separate recommendations for system modification and improvements are made.

Combustion performance, flame, and soot characteristics of gasoline–diesel pre-blended fuel in an optical compression-ignition engine

International Nuclear Information System (INIS)

Jeon, Joonho; Lee, Jong Tae; Kwon, Sang Il; Park, Sungwook

2016-01-01

Highlights: • Gasoline–diesel pre-blended fuel was investigated in an optical direct-injection diesel engine. • KIVA3V-CHEMKIN code modeled blended fuel spray and combustion with discrete multi-component model. • Flame and soot characteristics in the combustion chamber were shown by optical kits. • Combustion performance and soot emissions for gasoline–diesel blended fuel were discussed. - Abstract: Among the new combustion technologies available for internal combustion engines to enhance performance and reduce exhausted emissions, the homogeneous charge compression ignition method is one of the most effective strategies for the compression-ignition engine. There are some challenges to realize the homogeneous charge compression ignition method in the compression-ignition engine. The use of gasoline–diesel blended fuel has been suggested as an alternative strategy to take advantages of homogeneous charge compression ignition while overcoming its challenges. Gasoline and diesel fuels are reference fuels for the spark-ignition and compression-ignition engines, respectively, both of which are widely used. The application of both these fuels together in the compression-ignition engine has been investigated using a hybrid injection system combining port fuel injection (gasoline) and direct injection (diesel); this strategy is termed reactivity controlled compression ignition. However, the pre-blending of gasoline and diesel fuels for direct injection systems has been rarely studied. For the case of direct injection of pre-blended fuel into the cylinder, various aspects of blended fuels should be investigated, including their spray breakup, fuel/air mixing, combustion development, and emissions. In the present study, the use of gasoline–diesel pre-blended fuel in an optical single-cylinder compression-ignition engine was investigated under various conditions of injection timing and pressure. Furthermore, KIVA-3V release 2 code was employed to model the

Controllable and affordable utility-scale electricity from intermittent wind resources and compressed air energy storage (CAES)

International Nuclear Information System (INIS)

Cavallo, Alfred

2007-01-01

World wind energy resources are substantial, and in many areas, such as the US and northern Europe, could in theory supply all of the electricity demand. However, the remote or challenging location (i.e. offshore) and especially the intermittent character of the wind resources present formidable barriers to utilization on the scale required by a modern industrial economy. All of these technical challenges can be overcome. Long distance transmission is well understood, while offshore wind technology is being developed rapidly. Intermittent wind power can be transformed to a controllable power source with hybrid wind/compressed air energy storage (CAES) systems. The cost of electricity from such hybrid systems (including transmission) is affordable, and comparable to what users in some modern industrial economies already pay for electricity. This approach to intermittent energy integration has many advantages compared to the current strategy of forcing utilities to cope with supply uncertainty and transmission costs. Above all, it places intermittent wind on an equal technical footing with every other generation technology, including nuclear power, its most important long-term competitor

Feasibility study of hybrid retrofits to an isolated off-grid diesel power plant

International Nuclear Information System (INIS)

Rehman, S.; Ahmad, F.; Shaahid, S.M.; Shash, A.; El-Amin, I.M.; Al-Shehri, A.M.; Bakhashwain, J.M.

2007-01-01

The green sources of energy are being encouraged to reduce the environmental pollution and combat the global warming of the planet. A target of 12% usage of wind energy only has been agreed by the UNO country members to achieve by 2020. So, the power of the wind is being used to generate electricity both as grid connected and isolated wind-diesel hybrid power plants. This paper performed a pre-feasibility of wind penetration into an existing diesel plant of a village in north eastern part of Saudi Arabia. For simulation purpose, wind speed data from a near by airport and the load data from the village have been used. The hybrid system design tool HOMER has been used to perform the feasibility study. In the present scenario, for wind speed less than 6.0m/s the, the existing diesel power plant is the only feasible solution over the range of fuel prices used in the simulation. The wind diesel hybrid system becomes feasible at a wind speed of 6.0m/s or more and a fuel price of 0.1$/L or more. If the carbon tax is taken into consideration and subsidy is abolished then it is expected that the hybrid system become feasible. The maximum annual capacity shortage did not have any effect on the cost of energy which may be accounted for larger sizes of wind machines and diesel generators. It is recommended that the wind data must be collected at the village at three different heights using a wind mast of 40m for a minimum of one complete year and then the hybrid system must be re-designed. (author)

Hybrid electrical generation system utilizing wind, diesel and hydropower for operation of an underground zinc mine in southern Chile

Energy Technology Data Exchange (ETDEWEB)

Gridley, Norman [Minera El Toqui (Chile); Banto, Marcelo [Seawind Chile (Chile)

2010-07-01

This paper presents a hybrid electrical generation system used for underground zinc mine operations that utilizes wind, diesel and hydropower. This mine is located in Coyhaique and had a total energy consumption of 32,567 MWh in 2010 which is anticipated to increase by 25% in 2011. Power generation in this mine is independent of the power grid. It consists of four main portals: ventilation, electrical and drainage systems and ramp access to all mining zones. The technical details for all the parts of the mine and the hybrid generation system are given. A tabular form shows the energy consumed every month from 2005-2010 for all three systems involved, namely wind power generation, diesel generation and the hydro generation system. Benefits of this hybrid system include stability and constant power generation under variable loads. This system can also be applied to other mines using a grid. From the study it can be concluded that the hybrid system is environmentally friendly, economical and sustainable.

Optimization of an off-grid hybrid PV-wind-diesel-battery system

Energy Technology Data Exchange (ETDEWEB)

Merei, Ghada [RWTH Aachen Univ. (Germany). Electrochemical Energy Conversion and Storage Systems Group; Juelich Aachen Research Alliance, JARA-Energy (Germany); Sauer, Dirk Uwe [RWTH Aachen Univ. (Germany). Electrochemical Energy Conversion and Storage Systems Group; Juelich Aachen Research Alliance, JARA-Energy (Germany); RWTH Aachen Univ. (Germany). Inst. for Power Generation and Storage Systems (PGS)

2012-07-01

The power supply of remote sites and applications at minimal cost and with low emissions is an important issue when discussing future energy concepts. This paper presents the modelling and optimisation of a stand-alone hybrid energy system. The system consists of photovoltaic (PV) panels and a wind turbine as renewable power sources, a diesel generator for back-up power and batteries to store excess energy and to improve the system reliability. For storage the technologies of lithium-ion, lead-acid, vanadium redox-flow or a combination thereof are considered. In order to use different battery technologies at once, a battery management system (BMS) is needed. The presented BMS minimises operation cost while taking into account different battery operating points and ageing mechanisms. The system is modelled and implemented in Matlab/Simulink. As input, the model uses data of the irradiation, wind speed and air temperature measured in ten minute intervals for ten years in Aachen, Germany. The load is assumed to be that of a rural UMTS/GSM base station for telecommunication. For a timeframe of 20 years, the performance is evaluated and the total costs are determined. Using a genetic algorithm, component sizes and settings are then varied and the system re-evaluated to minimise the overall cost. The optimisation results show that using batteries in combination with the renewables is economic and ecologic. However, the best solution is to combine redox-flow batteries with the renewables. In addition, a power supply system consisting only of batteries, PV and wind generators can satisfy the power demand.

Design and thermodynamic analysis of a hybrid energy storage system based on A-CAES (adiabatic compressed air energy storage) and FESS (flywheel energy storage system) for wind power application

International Nuclear Information System (INIS)

Zhao, Pan; Dai, Yiping; Wang, Jiangfeng

2014-01-01

Electricity generated from renewable wind sources is highly erratic due to the intermittent nature of wind. This uncertainty of wind power can lead to challenges regarding power system operation and dispatch. Energy storage system in conjunction with wind energy system can offset these effects, making the wind power controllable. Moreover, the power spectrum of wind power exhibits that the fluctuations of wind power include various components with different frequencies and amplitudes. Thus, the hybrid energy storage system is more suitable for smoothing out the wind power fluctuations effectively rather than the independent energy storage system. A hybrid energy storage system consisting of adiabatic compressed air energy storage (A-CAES) system and flywheel energy storage system (FESS) is proposed for wind energy application. The design of the proposed system is laid out firstly. The A-CAES system operates in variable cavern pressure, constant turbine inlet pressure mode, whereas the FESS is controlled by constant power strategy. Then, the off-design analysis of the proposed system is carried out. Meanwhile, a parametric analysis is also performed to investigate the effects of several parameters on the system performance, including the ambient conditions, inlet temperature of compressor, storage cavern temperature, maximum and minimum pressures of storage cavern. - Highlights: • A wind-hybrid energy storage system composed of A-CAES and FESS is proposed. • The design of the proposed hybrid energy storage system is laid out. • The off-design analysis of the proposed system is carried out. • A parametric analysis is conducted to examine the system performance

Performance Analysis of Solar-Wind-Diesel-Battery Hybrid Energy System for KLIA Sepang Station of Malaysia

Science.gov (United States)

Shezan, S. K. A.; Saidur, R.; Hossain, A.; Chong, W. T.; Kibria, M. A.

2015-09-01

A large number of populations of the world live in rural or remote areas those are geographically isolated. Power supply and uninterrupted fuel transportation to produce electrical power for these remote areas poses a great challenge. Using renewable energy in hybrid energy system might be a pathway to solve this problem. Malaysia is a large hilly land with the gift of renewable energy resources. There is a good chance to utilize these renewable resources to produce electrical power and to limit the dependency on the fossil fuel as well as reduce the carbon emissions. In this perspective, a research is carried out to analyze the performance of a solar-wind-diesel-battery hybrid energy system for a remote area named “KLIA Sepang station” in the state of Selangor, Malaysia. In this study, a 56 kW hybrid energy system has been proposed that is capable to support more than 50 households and 6 shops in that area. Real time field data of solar radiation and wind speed is used for the simulation and optimization of operations using “Homer” renewable energy software. The proposed system can reduce CO2 emission by about 16 tons per year compared to diesel generator only. In the same time the Cost of energy (COE) of the optimized system is USD 5.126/kWh.The proposed hybrid energy system might be applicable for other parts of the world where the climate conditions are similar.

Optimal allocation and sizing of PV/Wind/Split-diesel/Battery hybrid energy system for minimizing life cycle cost, carbon emission and dump energy of remote residential building

International Nuclear Information System (INIS)

Ogunjuyigbe, A.S.O.; Ayodele, T.R.; Akinola, O.A.

2016-01-01

Highlights: • Genetic Algorithm is used for tri-objective design of hybrid energy system. • The objective is minimizing the Life Cycle Cost, CO_2 emissions and dump energy. • Small split diesel generators are used in place of big single diesel generator. • The split diesel generators are aggregable based on certain set of rules. • The proposed algorithm achieves the set objectives (LCC, CO_2 emission and dump). - Abstract: In this paper, a Genetic Algorithm (GA) is utilized to implement a tri-objective design of a grid independent PV/Wind/Split-diesel/Battery hybrid energy system for a typical residential building with the objective of minimizing the Life Cycle Cost (LCC), CO_2 emissions and dump energy. To achieve some of these objectives, small split Diesel generators are used in place of single big Diesel generator and are aggregable based on certain set of rules depending on available renewable energy resources and state of charge of the battery. The algorithm was utilized to study five scenarios (PV/Battery, Wind/Battery, Single big Diesel generator, aggregable 3-split Diesel generators, PV/Wind/Split-diesel/Battery) for a typical load profile of a residential house using typical wind and solar radiation data. The results obtained revealed that the PV/Wind/Split-diesel/Battery is the most attractive scenario (optimal) having LCC of $11,273, COE of 0.13 ($/kW h), net dump energy of 3 MW h, and net CO_2 emission of 13,273 kg. It offers 46%, 28%, 82% and 94% reduction in LCC, COE, CO_2 emission and dump energy respectively when compared to a single big Diesel generator scenario.

Using simple wind-diesel systems without energy storage to obtain high penetration and market acceptance in the near future

International Nuclear Information System (INIS)

Lundsager, P.; Sherwin, R.W. Jr.

1991-01-01

A wind/diesel hybrid power system combines wind energy technology with diesel generation to provide continous AC electrical power with reduced fuel consumption. The objectives of this paper are to summarize the reasoning behind the simple Wind-Diesel system concept using low or negative load operation of the diesels, including the diesel backdrive technique proposed by Atlantic Orient, and to outline a strategy within an international framework to make simple Wind-Diesel systems with standard induction generator wind turbines commercially available and accepted by the market. (au) (11 refs.)

Progress in energy generation for Canadian remote sites

Science.gov (United States)

Saad, Y.; Younes, R.; Abboudi, S.; Ilinca, A.; Nohra, C.

2016-07-01

Many remote areas around the world are isolated, for various reasons, from electricity networks. They are usually supplied with electricity through diesel generators. The cost of operation and transportation of diesel fuel in addition to its price have led to the procurement of a more efficient and environmentally greener method of supply. Various studies have shown that a wind-diesel hybrid system with compressed air storage (WDCAS) seems to be one of the best solutions, and presents itself as an optimal configuration for the electrification of isolated sites. This system allows significant fuel savings to be made because the stored compressed air is used to supercharge the engine. In order to optimize system performance and minimize fuel consumption, installation of a system for recovering and storing the heat of compression (TES) seems necessary. In addition, the use of hydro-pneumatic energy storage systems that use the same machine as the hydraulic pump and turbine allow us to store energy in tight spaces and, if possible, contribute to power generation. The scrupulous study of this technical approach will be the focus of our research which will validate (or not) the use of such a system for the regulation of frequency of electrical networks. In this article we will skim through the main research that recently examined the wind-diesel hybrid system which addressed topics such as adiabatic compression and hydro-pneumatic storage. Instead, we will offer (based on existing studies) a new ACP-WDCAS (wind-diesel hybrid system with adiabatic air compression and storage at constant pressure), which combines these three concepts in one system for the optimization of wind-diesel hybrid system.

Experimental investigations on performance of liquid desiccant-vapor compression hybrid air conditioner

International Nuclear Information System (INIS)

Mohan, B. Shaji; Tiwari, Shaligram; Maiya, M.P.

2015-01-01

A coupled desiccant column is integrated with a conventional room air conditioner (AC) to enhance dehumidification of the room air. One desiccant column (absorber) is placed after the evaporator the other (regenerator) after the condenser of the AC unit. Such a novel liquid desiccant vapour compression hybrid air conditioning system has been fabricated and tested in a balanced ambient room type calorimeter for very low flow rates of liquid desiccant (lithium bromide solution). The moisture from the cold supply air is transferred to the hot condenser air by the desiccant flowing in the loop, thereby complimenting the dehumidification of the room air at the evaporator. The supply air is also sensibly heated during the dehumidification process by liquid desiccant in the absorber, which together enables the hybrid system to maintain low humidity in the room. Whereas the liquid desiccant is regenerated by the condenser waste heat, the entire cooling is derived only by the AC unit. The experimental results show that an increase of room temperature reduces both dehumidification of process air and regeneration of liquid desiccant, whereas an increase of room specific humidity enhances both these for the flow rate of the liquid desiccant in the range of 0.2–1.6% of the air flow rate through the absorber. - Highlights: • A liquid desiccant vapor compression hybrid system is fabricated and tested. • The liquid desiccant reduces latent load but equally increases sensible load. • Hybrid system performance is studied for varying room temperature and humidity. • Higher room temperature lowers air dehumidification and desiccant regeneration. • Increase of room specific humidity enhances dehumidification and also regeneration

PV-diesel hybrid powers island nature reserve

Energy Technology Data Exchange (ETDEWEB)

Corkish, R. [University of New South Wales (Australia). Centre for Photovoltaic Engineering

2001-03-01

A short paper reports how by replacing a diesel-electric power supply with a PV-diesel-battery hybrid system, the diesel generator running time has been cut by 87%. The system provides all the power needs (including for the lighthouse, the lighthouse keeper's family, and a few visitors) on Montague Island nature reserve off Australia. The old system consisted of a pair of diesel-fuelled generator sets rated at 10 and 20 kVA. The main purposes for the changes were environmental, safety (in terms of transporting diesel fuel), and financial. Liquefied petroleum gas is now used for water heating and cooking. The reasons for not going for wind power are given. A diagram shows load and array power profiles for a May day in 1999.

Preliminary engineering design and cost of Advanced Compressed-Air Storage (ACAS) A-5 hybrid

Science.gov (United States)

Sosnowicz, E. J.; Blackman, J.; Woodhull, A. S.; Zaugg, P.

1981-08-01

The advanced compressed air energy (ACAS) plant investiated operates on a partial adiabatic, partial fuel fired cycle. Only a limited advancement in state-of-the-art technology is projected for this hybrid arrangement. The A-5 hybrid systems stores the heat of compression from the low pressure and intermediate pressure compressors in a thermal energy store (TES). The heat collected in the TES is available for preheating the air from the storage cavern prior to its entering the low pressure turbine combustor. This reduces the amount of fuel consumed during power generation. The fuel heat rate for the hybrid cycle is 2660 Btu/kWh as compared to approximately 4000 Btu/kWh for a conventional CAES plant. A virtual stand-off between the hybrid plant and a conventional CAES plant at 235 mills/kWh in 1990 dollars is shown. With a lower cost and increased fuel cost projections, the hybrid system operating cost is less than that for a conventional CAES plant.

Displacement of diesel fuel with wind energy in rural Alaskan villages. Final progress and project closeout report

Energy Technology Data Exchange (ETDEWEB)

Meiners, Dennis [Alaska Industrial Development and Export Authority, Anchorage, AK (United States); Drouhilet, Steve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Reeve, Brad [Alaska Industrial Development and Export Authority, Anchorage, AK (United States); Bergen, Matt [Kotzebue Electric Association, Kotzebue, AK (United States)

2002-03-11

The basic concept behind this project was to construct a wind diesel hybrid power system which combines and maximizes the intermittent and variable energy output of wind turbine(s) with diesel generator(s) to provide continuous high quality electric power to weak isolated mini-grids.

Using Atmospheric Pressure Tendency to Optimise Battery Charging in Off-Grid Hybrid Wind-Diesel Systems for Telecoms

Directory of Open Access Journals (Sweden)

Stephen Daniels

2013-06-01

Full Text Available Off grid telecom base stations in developing nations are powered by diesel generators. They are typically oversized and run at a fraction of their rated load for most of their operating lifetime. Running generators at partial load is inefficient and, over time, physically damages the engine. A hybrid configuration uses a battery bank, which powers the telecoms’ load for a portion of the time. The generator only operates when the battery bank needs to be charged. Adding a wind turbine further reduces the generator run hours and saves fuel. The generator is oblivious to the current wind conditions, which leads to simultaneous generator-wind power production. As the batteries become charged by the generator, the wind turbine controller is forced to dump surplus power as heat through a resistive load. This paper details how the relationship between barometric pressure and wind speed can be used to add intelligence to the battery charger. A Simulink model of the system is developed to test the different battery charging configurations. This paper demonstrates that if the battery charger is aware of upcoming wind conditions, it will provide modest fuel savings and reduce generator run hours in small-scale hybrid energy systems.

Market penetration of large wind/diesel systems

International Nuclear Information System (INIS)

Kronborg, T.

1992-01-01

Burmeister ampersand Wain is developing a large size wind/diesel package in collaboration with Micon, the Danish wind turbine manufacturer, and the Danish utility NESA. The package comprises an initial calculation of the technical feasibility and the economic viability of an actual project, installing the optimum number of large wind turbines, and service, operation, and maintenance as needed. The concept should be seen as an addition to existing diesel-based power stations. Wind turbines are especially advantageous in smaller diesel-based electrical systems in the 1-20 MW range because such systems can have high fuel costs and expensive maintenance. Analysis of the market for the wind/diesel concept indicates islands and remote areas with limited population are likely candidates for implementation of wind/diesel systems. An example of an economic analysis of a wind/diesel application on an isolated island is presented, showing the cost savings possible. To obtain practical experience and to demonstrate the wind/diesel concept, a MW-size demonstration plant is being constructed in Denmark

Review of wind/diesel strategies

Energy Technology Data Exchange (ETDEWEB)

Infield, D G; Lipman, N H; Musgrove, P J; Slack, G W

1983-12-01

A large potential demand exists for electricity in areas isolated from grid supply. Diesel generation in these usually remote areas is expensive and wind/diesel systems, with the wind turbine viewed primarily as a fuel saver, can be seen as attractive. Integration of wind energy is not straightforward, and in particular can cause operational problems for the diesel generator set. These difficulties are discussed and various approaches, including a twin diesel system, are presented. The role of energy storage is examined, both to deal with operational problems and to improve wind-energy utilisation. An example of battery storage is developed in some detail. A summary of actual installations and their performance is included to highlight some of the problems, and indicate the approaches being taken to deal with them.

A review on the recent development of solar absorption and vapour compression based hybrid air conditioning with low temperature storage

Directory of Open Access Journals (Sweden)

Noor D. N.

2016-01-01

Full Text Available Conventional air conditioners or vapour compression systems are main contributors to energy consumption in modern buildings. There are common environmental issues emanating from vapour compression system such as greenhouse gas emission and heat wastage. These problems can be reduced by adaptation of solar energy components to vapour compression system. However, intermittence input of daily solar radiation was the main issue of solar energy system. This paper presents the recent studies on hybrid air conditioning system. In addition, the basic vapour compression system and components involved in the solar air conditioning system are discussed. Introduction of low temperature storage can be an interactive solution and improved economically which portray different modes of operating strategies. Yet, very few studies have examined on optimal operating strategies of the hybrid system. Finally, the findings of this review will help suggest optimization of solar absorption and vapour compression based hybrid air conditioning system for future work while considering both economic and environmental factors.

The economics of a variable speed wind-diesel

International Nuclear Information System (INIS)

Moll, W.

1992-01-01

A remote community power supply system generating over 1,000 kWH/d will have at least one diesel generator running all the time. If one or more wind turbine generators are added to such a system, the diesel generator will produce less power when wind speeds are adequate, but its fuel efficiency will gradually decrease as load decreases. In the variable speed wind/diesel concept, the diesel rpm is reduced with decreasing load and a high fuel efficiency is maintained over virtually the full power range. The outputs of the diesel and wind turbine generators are fed into an inverter which synthesizes a desired voltage wave-shape with controlled magnitude and frequency. The variable speed wind/diesel concept may make vertical axis wind turbines suitable for remote community power supply because the inverter effectively isolates the power ripple of the wind turbine. A possible wind/diesel system configuration using the variable speed concept is illustrated. The economics of a 50-kW variable speed diesel and a 80-kW variable speed wind turbine generator was analyzed. Going from a constant speed diesel generator to a variable speed generator operating at 55% capacity factor, a 6% fuel saving was achieved. Adding one 80-kW wind turbine increased fuel savings to 32% at 5 m/s wind speed, but the unit energy cost rose 8.5%. At 7 m/s wind speed, fuel savings were 59% and energy savings were 7.8%. Economics are better for a peaking variable speed 50-kW wind/diesel system added to an existing diesel system to extend the installed capacity. At 7 m/s wind speed the fuel savings translate into ca $40,000 over 10 y and purchase of a $150,000 diesel generator is postponed. 7 figs., 1 tab

TRANSIENT ANALYSIS OF WIND DIESEL POWER SYSTEM WITH FLYWHEEL ENERGY STORAGE

Directory of Open Access Journals (Sweden)

S. SUJITH

2017-10-01

Full Text Available Wind-Diesel Hybrid power generation is a viable alternative for generating continuous power to isolated power system areas which have inconsistent but potential wind power. The unpredictable nature of variable power from Wind generator to the system is compensated by Diesel generator, which supplies the deficit in generated power from wind to meet the instantaneous system load. However, one of the major challenges for such a system is the higher probability of transients in the form of wind and load fluctuations. This paper analyses the application of Flywheel Energy storage system (FESS to meet the transients during wind-speed and load fluctuations around high wind operation. The power system architecture, the distributed control mechanism governing the flow of power transfer and the modelling of major system components has been discussed and the system performances have been validated using MATLAB /Simulink software. Two cases of transient stages around the high wind system operation are discussed. The simulation results highlight the effective usage of FESS in reducing the peak overshoot of active power transients, smoothes the active power curves and helps in reducing the diesel consumption during the flywheel discharge period, without affecting the continuous power supply for meeting the instantaneous load demand.

Demand response impacts on off-grid hybrid photovoltaic-diesel generator microgrids

Directory of Open Access Journals (Sweden)

Aaron St. Leger

2015-08-01

Full Text Available Hybrid microgrids consisting of diesel generator set(s and converter based power sources, such as solar photovoltaic or wind sources, offer an alternative to generator based off-grid power systems. The hybrid approach has been shown to be economical in many off-grid applications and can result in reduced generator operation, fuel requirements, and maintenance. However, the intermittent nature of demand and renewable energy sources typically require energy storage, such as batteries, to properly operate the hybrid microgrid. These batteries increase the system cost, require proper operation and maintenance, and have been shown to be unreliable in case studies on hybrid microgrids. This work examines the impacts of leveraging demand response in a hybrid microgrid in lieu of energy storage. The study is performed by simulating two different hybrid diesel generator—PV microgrid topologies, one with a single diesel generator and one with multiple paralleled diesel generators, for a small residential neighborhood with varying levels of demand response. Various system designs are considered and the optimal design, based on cost of energy, is presented for each level of demand response. The solar resources, performance of solar PV source, performance of diesel generators, costs of system components, maintenance, and operation are modeled and simulated at a time interval of ten minutes over a twenty-five year period for both microgrid topologies. Results are quantified through cost of energy, diesel fuel requirements, and utilization of the energy sources under varying levels of demand response. The results indicate that a moderate level of demand response can have significant positive impacts to the operation of hybrid microgrids through reduced energy cost, fuel consumption, and increased utilization of PV sources.

Dual-fuelling of a direct-injection automotive diesel engine by diesel and compressed natural gas

International Nuclear Information System (INIS)

Pirouzpanah, V.; Mohammadi Kosha, A.; Mosseibi, A.; Moshirabadi, J.; Gangi, A.; Moghadaspour, M.

2000-01-01

Application of Compressed Natural Gas in diesel engines has always been important, especially in the field of automotive engineering. This is due to easy accessibility, better mixing quality and good combustion characteristics of the Compressed Natural Gas fuel. In this study the application of Compressed Natural Gas fuel along with diesel oil in a heavy duty direct-injection automotive diesel engine is experimentally investigated. In order to convert a diesel engine into a diesel-gas one, the so called m ixed diesel-gas a pproach has been used and for this purpose a carbureted Compressed Natural Gas fuel system has been designed and manufactured. For controlling quantity of Compressed Natural Gas, the gas valve is linked to the diesel fuel injection system by means of a set of rods. Then, the dual-fuel system is adjusted so that, at full load conditions, the quantity of diesel fuel is reduced to 20% and 80% of its equivalent energy is substituted by Compressed Natural Gas fuel. Also injection pressure of pilot jet is increased by 11.4%. Performance and emission tests are conducted under variation of load and speed on both diesel and diesel-gas engines. Results show that, with equal power and torque, the diesel-gas engine has the potential to improve overall engine performance and emission. For example, at rated power and speed, fuel economy increases by 5.48%, the amount of smoke decreases by 78%, amount of CO decreases by 64.3% and mean exhaust gas temperature decreases by 6.4%

Hybrid Solar – Wind – Diesel Systems for Rural Application in North ...

African Journals Online (AJOL)

Bheema

,Mekelle. University, Mekelle ... used to simulate and generate feasible solution through combinations of photovoltaic, Wind. Turbines and Diesel ... significant impact on preventing problems associated with deforestation, environmental effects.

Experimental study into a hybrid PCCI/CI concept for next-generation heavy-duty diesel engines

NARCIS (Netherlands)

Doosje, E.; Willems, F.P.T.; Baert, R.S.G.; Dijk, M.D. van

2012-01-01

This paper presents the first results of an experimental study into a hybrid combustion concept for next-generation heavy-duty diesel engines. In this hybrid concept, at low load operating conditions, the engine is run in Pre-mixed Charge Compression Ignition (PCCI) mode, whereas at high load

Optimal Design of Wind-PV-Diesel-Battery System using Genetic Algorithm

Science.gov (United States)

Suryoatmojo, Heri; Hiyama, Takashi; Elbaset, Adel A.; Ashari, Mochamad

Application of diesel generators to supply the load demand on isolated islands in Indonesia has widely spread. With increases in oil price and the concerns about global warming, the integration of diesel generators with renewable energy systems have become an attractive energy sources for supplying the load demand. This paper performs an optimal design of integrated system involving Wind-PV-Diesel-Battery system for isolated island with CO2 emission evaluation by using genetic algorithm. The proposed system has been designed for the hybrid power generation in East Nusa Tenggara, Indonesia-latitude 09.30S, longitude 122.0E. From simulation results, the proposed system is able to minimize the total annual cost of the system under study and reduce CO2 emission generated by diesel generators.

Effects of air jet duration and timing on the combustion characteristics of high-pressure air jet controlled compression ignition combustion mode in a hybrid pneumatic engine

International Nuclear Information System (INIS)

Long, Wuqiang; Meng, Xiangyu; Tian, Jiangping; Tian, Hua; Cui, Jingchen; Feng, Liyan

2016-01-01

Highlights: • A 3-D CFD model of the power cylinder in HPE was developed. • High-pressure air JCCI combustion mode includes two-stage high-temperature reaction. • The combustion phasing of the pre-mixture is controllable via the SOJ timing. • There exists an optimum SOJ timing for obtaining the highest combustion efficiency and shortest burning duration. - Abstract: The high-pressure air jet controlled compression ignition (JCCI) combustion mode was employed to control the premixed diesel compression ignition combustion phasing by using the compound thermodynamic cycle under all operating conditions, which is accomplished in a hybrid pneumatic engine (HPE). A three-dimensional computational fluid dynamics (CFD) numerical simulation coupled with reduced n-heptane chemical kinetics mechanism has been applied to investigate the effects of high-pressure air jet duration and the start of jet (SOJ) timing on the combustion characteristics in the power cylinder of HPE. By sweeping the high-pressure air jet durations from 6 to 14 °CA and SOJ timings from −12 °CA ATDC to the top dead center (TDC) under the air jet temperatures of 400 and 500 K, respectively, the low- and high-temperature reactions, combustion efficiency, as well as the combustion phasing and burning duration have been analyzed in detail. The results illustrated that a longer air jet duration results in a higher peak in the first-stage high-temperature reaction, and the short air jet duration of 6 °CA can lead to a higher combustion efficiency. The SOJ timing sweep results showed that there exists an optimum timing for obtaining the highest combustion efficiency and shortest burning duration.

Status of Wind-Diesel Applications in Arctic Climates: Preprint

Energy Technology Data Exchange (ETDEWEB)

Baring-Gould, I.; Corbus, D.

2007-12-01

The rising cost of diesel fuel and the environmental regulation for its transportation, use, and storage, combined with the clear impacts of increased arctic temperatures, is driving remote communities to examine alternative methods of providing power. Over the past few years, wind energy has been increasingly used to reduce diesel fuel consumption, providing economic, environmental, and security benefits to the energy supply of communities from Alaska to Antarctica. This summary paper describes the current state of wind-diesel systems, reviews the operation of wind-diesel plants in cold climates, discusses current research activities pertaining to these systems, and addresses their technical and commercial challenges. System architectures, dispatch strategies, and operating experience from a variety of wind-diesel systems in Alaska will be reviewed. Specific focus will also be given to the control of power systems with large amounts of wind generation and the complexities of replacing diesel engine waste heat with excess wind energy, a key factor in assessing power plants for retrofit. A brief overview of steps for assessing the viability of retrofitting diesel power systems with wind technologies will also be provided. Because of the large number of isolated diesel minigrids, the market for adding wind to these systems is substantial, specifically in arctic climates and on islands that rely on diesel-only power generation.

Economic and environmental evaluation of compressed-air cars

International Nuclear Information System (INIS)

Creutzig, Felix; Kammen, Daniel M; Papson, Andrew; Schipper, Lee

2009-01-01

Climate change and energy security require a reduction in travel demand, a modal shift, and technological innovation in the transport sector. Through a series of press releases and demonstrations, a car using energy stored in compressed air produced by a compressor has been suggested as an environmentally friendly vehicle of the future. We analyze the thermodynamic efficiency of a compressed-air car powered by a pneumatic engine and consider the merits of compressed air versus chemical storage of potential energy. Even under highly optimistic assumptions the compressed-air car is significantly less efficient than a battery electric vehicle and produces more greenhouse gas emissions than a conventional gas-powered car with a coal intensive power mix. However, a pneumatic-combustion hybrid is technologically feasible, inexpensive and could eventually compete with hybrid electric vehicles.

A study of diesel-hydrogen fuel exhaust emissions in a compression ignition engine/generator assembly

International Nuclear Information System (INIS)

Karri, V.; Hafez, H.A.; Kirkegaard, J.F.

2006-01-01

A compression engine and duel-fuel supply system was studied in order to determine the influence of hydrogen gas on a diesel engine's exhaust system. Commercially available solenoid valves and pulse actuators were used in a customized mechatronic control unit (MICU) to inject the hydrogen gas into the cylinders during the experiments. The MICU was designed as a generic external attachment. Diesel fuel was used to ignite the hydrogen gas-air mixture after compression. Various different electrical loads were then applied using an alternator in order to stimulate the engine governor and control diesel flow. Results of the study showed that measured carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO x ) loads of exhaust emissions increased, while emissions of carbon dioxide (CO 2 ) decreased. Results also showed that higher temperatures and levels of NO x occurred when hydrogen was mixed with the induced air. It was concluded that higher levels of hydrogen may be needed to reduce emissions. 17 refs., 5 tabs., 2 figs

Characterization of Diesel and Gasoline Compression Ignition Combustion in a Rapid Compression-Expansion Machine using OH* Chemiluminescence Imaging

Science.gov (United States)

Krishnan, Sundar Rajan; Srinivasan, Kalyan Kumar; Stegmeir, Matthew

2015-11-01

Direct-injection compression ignition combustion of diesel and gasoline were studied in a rapid compression-expansion machine (RCEM) using high-speed OH* chemiluminescence imaging. The RCEM (bore = 84 mm, stroke = 110-250 mm) was used to simulate engine-like operating conditions at the start of fuel injection. The fuels were supplied by a high-pressure fuel cart with an air-over-fuel pressure amplification system capable of providing fuel injection pressures up to 2000 bar. A production diesel fuel injector was modified to provide a single fuel spray for both diesel and gasoline operation. Time-resolved combustion pressure in the RCEM was measured using a Kistler piezoelectric pressure transducer mounted on the cylinder head and the instantaneous piston displacement was measured using an inductive linear displacement sensor (0.05 mm resolution). Time-resolved, line-of-sight OH* chemiluminescence images were obtained using a Phantom V611 CMOS camera (20.9 kHz @ 512 x 512 pixel resolution, ~ 48 μs time resolution) coupled with a short wave pass filter (cut-off ~ 348 nm). The instantaneous OH* distributions, which indicate high temperature flame regions within the combustion chamber, were used to discern the characteristic differences between diesel and gasoline compression ignition combustion. The authors gratefully acknowledge facilities support for the present work from the Energy Institute at Mississippi State University.

Wind-diesel and distributed diesel co-generation in remote communities

International Nuclear Information System (INIS)

Lodge, M.A.

1995-01-01

One of the most popular and feasible strategies to reduce costs for electrical and other energy supply in remote communities is the development of wind-diesel systems. In these systems, a significant share of the electrical energy requirements of a community can be provided by wind turbines connected to the community electrical distribution system. One of the characteristics of the systems having a relatively large ratio of wind turbine capacity to community load, called High Penetration Wind-Diesel Systems (HPWDS), is that during high wind periods there will be electrical energy available in excess of the net load on the system. An important concept of the HPWDS strategy is that this excess energy can be directed to a practical use, such as heating. The concept of HPWDS was shown to be economically and technically feasible in communities having no heat recovery on the diesel plants. It proved to be even more attractive as a strategy for self sufficiency of electrical supply in communities with waste heat recovery. 1 fig., 1 tab

A low-cost hybrid drivetrain concept based on compressed air energy storage

International Nuclear Information System (INIS)

Brown, T.L.; Atluri, V.P.; Schmiedeler, J.P.

2014-01-01

Highlights: • A new pneumatic hybrid concept is introduced. • A proof-of-concept prototype system is built and tested. • The experimental system has a round-trip efficiency of just under 10%. • A thermodynamics model is used to predict the performance of modified designs. • An efficiency of nearly 50% is possible with reasonable design changes. - Abstract: This paper introduces a new low-cost hybrid drivetrain concept based on compressed air energy storage. In contrast to most contemporary approaches to pneumatic hybridization, which require modification to the primary power plant, this concept is based on a stand-alone pneumatic system that could be readily integrated with existing vehicles. The pneumatic system consists of an air tank and a compressor–expander that is coupled to the rest of the drivetrain via an infinitely variable transmission. Rather than incorporating more expensive technologies such as variable valve timing or a variable compression ratio compressor, a fixed valve system consisting of a rotary valve and passive check valves is optimized to operate efficiently over a range of tank pressures. The feasibility of this approach is established by thermodynamic modeling and the construction of a proof-of-concept prototype, which is also used to fine tune model parameters. While the proof-of-concept system shows a round trip efficiency of just under 10%, modeling shows that a round trip efficiency of 26% is possible with a revised design. If waste heat from the engine is used to maintain an elevated tank temperature, efficiencies of nearly 50% may be possible, indicating that the concept could be effective for practical hybridization of passenger vehicles

Wind diesel systems - design assessment and future potential

DEFF Research Database (Denmark)

Infield, D.G.; Scotney, A.; Lundsager, P.

1992-01-01

Diesels are the obvious form. of back-up electricity generation in small to medium sized wind systems. High wind penetrations pose significant technical problems for the system designer, ranging from component sizing to control specification and dynamic stability. A key role is seen for proven...... system models for assessing both dynamic characteristics and overall performance and economics. An introduction is provided to the Wind Diesel Engineering Design Toolkit currently under development (for implementation on PC) by a consortium of leading wind diesel experts, representing six European...

Main results from Risoe's wind-diesel programme 1984-1990

International Nuclear Information System (INIS)

Lundsager, P.; Christensen, C.J.

1991-12-01

The report presents the results of the wind-diesel work done in projects at Risoe National Laboratory during the years 1984-90, including important earlier publications as appendices. The partners in the original joint project were Risoe National Laboratory, Denmark, and Chalmers University of Technology, Sweden. Chalmers has constructed and laboratory tested an advanced wind-diesel-battery system with variable speed operation of the wind turbine, while Risoe has established a flexible and versatile wind-diesel test facility and field tested Chalmers system. As part of the subsequent EFP projects Risoe designed and constructed a simple wind-diesel system without storage, characterized by several innovative features. This concept was part of a ''simple wind-diesel systems strategy'', in which immediate cost-effectiveness is ensured by the simplicity and reliability of the design. Dynamic computer models were developed for system design and analysis purposes, and a general logistic computer model was developed for the determination of fuel savings and power supply capabilities for a number of system configurations. In addition to a considerable body of experience the main results of activities are: A versatile wind-diesel test facility and a proposed standard wind-diesel test procedure. Two wind-diesel systems at each end of the spectrum of configurations. Computer models for logistic and dynamic modelling. The two systems represent the very simple system concept, believed to be a presently economically optimal configuration, and the very sophisticated concept believed to be a future optimal configuration. (au) (6 tabs., 67 ills., 25 refs.)

Feasibility Study of Standalone PV-Wind-Diesel Energy Systems for Coastal Residential Application in Pekan, Pahang

Directory of Open Access Journals (Sweden)

Zailan Roziah

2017-01-01

Full Text Available Techno economic study is feasible to optimize the usage of renewable energy components that targeting low cost of electricity generation system. The selected case study area is coastal area in Pekan, Pahang, Malaysia. The autonomous system designed in this study is hybrid standalone PV-wind-diesel energy system to fulfil a basic power demand of 20.1 kWh/day. Such power system was designed and optimized further to meet the power demand at a minimum cost of energy using energy optimization software, Hybrid Optimization Model for Electric Renewables (HOMER. The analysis focused on the operational characteristics and economics. The standalone PV-wind-diesel energy system has total net present cost about $61, 911 with cost of energy $0.66/kWh. Apparently, the generation of electricity from both wind turbine and PV can be inflated with the diesel generator. In comparison, return of investment (ROI value turned out lower for Feed in Tariff (FIT as compared to self-sustained house. Payback period also longer for FIT program that makes the selling back of electricity generated to Tenaga National Berhad (TNB is considered not favourable.

Compressed air energy storage system reservoir size for a wind energy baseload power plant

Energy Technology Data Exchange (ETDEWEB)

Cavallo, A.J.

1996-12-31

Wind generated electricity can be transformed from an intermittent to a baseload resource using an oversized wind farm in conjunction with a compressed air energy storage (CAES) system. The size of the storage reservoir for the CAES system (solution mined salt cavern or porous media) as a function of the wind speed autocorrelation time (C) has been examined using a Monte Carlo simulation for a wind class 4 (wind power density 450 W m{sup -2} at 50 m hub height) wind regime with a Weibull k factor of 2.5. For values of C typically found for winds over the US Great Plains, the storage reservoir must have a 60 to 80 hour capacity. Since underground reservoirs account for only a small fraction of total system cost, this larger storage reservoir has a negligible effect on the cost of energy from the wind energy baseload system. 7 refs., 2 figs., 1 tab.

DOE/NREL supported wind energy activities in Indonesia

Energy Technology Data Exchange (ETDEWEB)

Drouilhet, S.

1997-12-01

This paper describes three wind energy related projects which are underway in Indonesia. The first is a USAID/Winrock Wind for Island and Nongovernmental Development (WIND) project. The objectives of this project are to train local nongovernmental organizations (NGOs) in the siting, installation, operation, and maintenance of small wind turbines. Then to install up to 20 wind systems to provide electric power for productive end uses while creating micro-enterprises which will generate enough revenue to sustain the wind energy systems. The second project is a joint Community Power Corporation/PLN (Indonesian National Electric Utility) case study of hybrid power systems in village settings. The objective is to evaluate the economic viability of various hybrid power options for several different situations involving wind/photovoltaics/batteries/diesel. The third project is a World Bank/PLN preliminary market assessment for wind/diesel hybrid systems. The objective is to estimate the size of the total potential market for wind/diesel hybrid power systems in Indonesia. The study will examine both wind retrofits to existing diesel mini-grids and new wind-diesel plants in currently unelectrified villages.

Perspective for Fibre-Hybrid Composites in Wind Energy Applications

Science.gov (United States)

2017-01-01

Increasing the efficiency of wind turbines will be vital for the wind energy sector to continue growing. The drive for increased efficiency is pushing turbine manufacturers to shift from glass fibre composite blades towards carbon/glass fibre-hybrid composite blades. This shift brings significant challenges in terms of optimising the design and understanding the failure of these new blade materials. This review therefore surveys the literature on fibre-hybrid composites, with an emphasis on aspects that are relevant for turbine blade materials. The literature on tensile, flexural, compressive, and fatigue performance is critically assessed and areas for future research are identified. Numerical simulations of fibre-hybrid composites have reached a reasonable maturity for tensile failure, but significant progress is required for flexural, compressive, and fatigue failure. Fatigue failure of fibre-hybrid composites in particular, requires more careful attention from both a modelling and experimental point of view. PMID:29117126

Perspective for Fibre-Hybrid Composites in Wind Energy Applications

Directory of Open Access Journals (Sweden)

Yentl Swolfs

2017-11-01

Full Text Available Increasing the efficiency of wind turbines will be vital for the wind energy sector to continue growing. The drive for increased efficiency is pushing turbine manufacturers to shift from glass fibre composite blades towards carbon/glass fibre-hybrid composite blades. This shift brings significant challenges in terms of optimising the design and understanding the failure of these new blade materials. This review therefore surveys the literature on fibre-hybrid composites, with an emphasis on aspects that are relevant for turbine blade materials. The literature on tensile, flexural, compressive, and fatigue performance is critically assessed and areas for future research are identified. Numerical simulations of fibre-hybrid composites have reached a reasonable maturity for tensile failure, but significant progress is required for flexural, compressive, and fatigue failure. Fatigue failure of fibre-hybrid composites in particular, requires more careful attention from both a modelling and experimental point of view.

Perspective for Fibre-Hybrid Composites in Wind Energy Applications.

Science.gov (United States)

Swolfs, Yentl

2017-11-08

Increasing the efficiency of wind turbines will be vital for the wind energy sector to continue growing. The drive for increased efficiency is pushing turbine manufacturers to shift from glass fibre composite blades towards carbon/glass fibre-hybrid composite blades. This shift brings significant challenges in terms of optimising the design and understanding the failure of these new blade materials. This review therefore surveys the literature on fibre-hybrid composites, with an emphasis on aspects that are relevant for turbine blade materials. The literature on tensile, flexural, compressive, and fatigue performance is critically assessed and areas for future research are identified. Numerical simulations of fibre-hybrid composites have reached a reasonable maturity for tensile failure, but significant progress is required for flexural, compressive, and fatigue failure. Fatigue failure of fibre-hybrid composites in particular, requires more careful attention from both a modelling and experimental point of view.

Multi-objective design of PV-wind-diesel-hydrogen-battery systems

Energy Technology Data Exchange (ETDEWEB)

Dufo-Lopez, Rodolfo; Bernal-Agustin, Jose L. [Department of Electrical Engineering, University of Zaragoza, Calle Maria de Luna 3, 50018-Zaragoza (Spain)

2008-12-15

This paper presents, for the first time, a triple multi-objective design of isolated hybrid systems minimizing, simultaneously, the total cost throughout the useful life of the installation, pollutant emissions (CO{sub 2}) and unmet load. For this task, a multi-objective evolutionary algorithm (MOEA) and a genetic algorithm (GA) have been used in order to find the best combination of components of the hybrid system and control strategies. As an example of application, a complex PV-wind-diesel-hydrogen-battery system has been designed, obtaining a set of possible solutions (Pareto Set). The results achieved demonstrate the practical utility of the developed design method. (author)

In-vehicle measurement of ultrafine particles on compressed natural gas, conventional diesel, and oxidation-catalyst diesel heavy-duty transit buses.

Science.gov (United States)

Hammond, Davyda; Jones, Steven; Lalor, Melinda

2007-02-01

Many metropolitan transit authorities are considering upgrading transit bus fleets to decrease ambient criteria pollutant levels. Advancements in engine and fuel technology have lead to a generation of lower-emission buses in a variety of fuel types. Dynamometer tests show substantial reductions in particulate mass emissions for younger buses (vehicle particle number concentration measurements on conventional diesel, oxidation-catalyst diesel and compressed natural gas transit buses are compared to estimate relative in-vehicle particulate exposures. Two primary consistencies are observed from the data: the CNG buses have average particle count concentrations near the average concentrations for the oxidation-catalyst diesel buses, and the conventional diesel buses have average particle count concentrations approximately three to four times greater than the CNG buses. Particle number concentrations are also noticeably affected by bus idling behavior and ventilation options, such as, window position and air conditioning.

IMPLEMENTATION OF DIOXANE AND DIESEL FUEL BLENDS TO REDUCE EMISSION AND TO IMPROVE PERFORMANCE OF THE COMPRESSION IGNITION ENGINE

OpenAIRE

SENDILVELAN S.; SUNDAR RAJ C.

2017-01-01

Performance of a compression ignition engine fuelled with 1, 4 Dioxane- diesel blends is evaluated. A single-cylinder, air-cooled, direct injection diesel engine developing a power output of 5.2 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel subsequently; five fuel blends namely 90:10, 80:20, 70:30, 60:40 and 50:50 percentages by volume of diesel and dioxane were prepared and tested in the diesel engine. Engine performance and emission data were used to optimize ...

Development of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine

Energy Technology Data Exchange (ETDEWEB)

Shenghua, L.; Ziyan, W.; Jiang, R. [Xi' an Jiaotong Univ. (China). Dept. of Automotive Engineering

2003-09-01

A natural gas and diesel dual-fuel turbocharged compression ignition (CI) engine is developed to reduce emissions of a heavy-duty diesel engine. The compressed natural gas (CNG) pressure regulator is specially designed to feed back the boost pressure to simplify the fuel metering system. The natural gas bypass improves the engine response to acceleration. The modes of diesel injection are set according to the engine operating conditions. The application of honeycomb mixers changes the flowrate shape of natural gas and reduces hydrocarbon (HC) emission under low-load and lowspeed conditions. The cylinder pressures of a CI engine fuelled with diesel and dual fuel are analysed. The introduction of natural gas makes the ignition delay change with engine load. Under the same operating conditions, the emissions of smoke and NO{sub x} from the dual-fuel engine are both reduced. The HC and CO emissions for the dual-fuel engine remain within the range of regulation. (Author)

Integration of Xantrex HY-100 Hybrid Inverter with an AC Induction Wind Turbine

Energy Technology Data Exchange (ETDEWEB)

Corbus, D.; Newcomb, C.; Friedly, S.

2003-05-01

Several issues must be addressed before solid-state inverters can be used in wind-diesel systems with larger wind turbines. This project addresses those issues by using a commercial hybrid inverter designed for PV-diesel systems and modifying the inverter for use with an AC induction wind turbine. Another approach would have entailed building an inverter specifically for use with an AC induction wind turbine, but that was beyond the scope of this project. The inverter chosen for this project was a Xantrex HY-100, an inverter designed for PV systems. The unit consists of an inverter/rectifier bridge, a generator interface contactor, a battery charge controller, a hybrid controller, and the associated control electronics. Details of the inverter may be found in Appendix A. A twofold approach was taken to integrating the existing inverter for use with an AC induction wind turbine: 1) development of a detailed model to model both steady-state and transient behavior of the system, and 2) modification and testing of the inverter with an induction wind turbine based on the modeling results. This report describes these two tasks.

BENEFITS AND CHALLENGES OF VARIABLE COMPRESSION RATIO AT DIESEL ENGINES

Directory of Open Access Journals (Sweden)

Radivoje B Pešić

2010-01-01

Full Text Available The compression ratio strongly affects the working process and provides an exceptional degree of control over engine performance. In conventional internal combustion engines, the compression ratio is fixed and their performance is therefore a compromise between conflicting requirements. One fundamental problem is that drive units in the vehicles must successfully operate at variable speeds and loads and in different ambient conditions. If a diesel engine has a fixed compression ratio, a minimal value must be chosen that can achieve a reliable self-ignition when starting the engine in cold start conditions. In diesel engines, variable compression ratio provides control of peak cylinder pressure, improves cold start ability and low load operation, enabling the multi-fuel capability, increase of fuel economy and reduction of emissions. This paper contains both theoretical and experimental investigation of the impact that automatic variable compression ratios has on working process parameters in experimental diesel engine. Alternative methods of implementing variable compression ratio are illustrated and critically examined.

Some results concerning no-storage wind-diesel systems control

Directory of Open Access Journals (Sweden)

Ciprian VLAD

2006-12-01

Full Text Available This paper deal with the dynamics of an autonomous no storage wind-diesel system, comprising a diesel generator and a controlled wind system with a hypo/hyper synchronous cascade. The objective is to maximize the wind energy penetration rate, by an optimization control system, respecting the quality standard concerning the frequency deviation in the AC local grid. Also, the influence of the diesel drive train on the system’s dynamics performances is discussed.

Hybrid Test Bed of Wind Electric Generator with Photovoltaic Panels

OpenAIRE

G.D.Anbarasi Jebaselvi; S.Paramasivam

2014-01-01

Driven by the increasing costs of power production and decreasing fossil fuel reserves with the addition of global environmental concerns, renewable energy is now becoming significant fraction of total electricity production in the world. Advancements in the field of wind electric generator technology and power electronics help to achieve rapid progress in hybrid power system which mainly involves wind, solar and diesel energy with a good battery back-up. Here the discussion brings about the ...

Design of an off-grid hybrid PV/wind power system for remote mobile base station: A case study

Directory of Open Access Journals (Sweden)

Mulualem T. Yeshalem

2017-01-01

Full Text Available There is a clear challenge to provide reliable cellular mobile service at remote locations where a reliable power supply is not available. So, the existing Mobile towers or Base Transceiver Station (BTSs uses a conventional diesel generator with backup battery banks. This paper presents the solution to utilizing a hybrid of photovoltaic (PV solar and wind power system with a backup battery bank to provide feasibility and reliable electric power for a specific remote mobile base station located at west arise, Oromia. All the necessary modeling, simulation, and techno-economic evaluation are carried out using Hybrid Optimization Model for Electric Renewable (HOMER software. The best optimal system configurations namely PV/Battery and PV/Wind/Battery hybrid systems are compared with the conventional stand-alone diesel generator (DG system. Findings indicated that PV array and battery is the most economically viable option with the total net present cost (NPC of $\\$$57,508 and per unit cost of electricity (COE of $\\$$0.355. Simulation results show that the hybrid energy systems can minimize the power generation cost significantly and can decrease CO2 emissions as compared to the traditional diesel generator only. The sensitivity analysis is also carried out to analysis the effects of probable variation in solar radiation, wind speed, diesel price and average annual energy usage of the system load in the optimal system configurations.

Compressed Air Energy Storage System Control and Performance Assessment Using Energy Harvested Index

Directory of Open Access Journals (Sweden)

Hanif SedighNejad

2014-01-01

Full Text Available In this paper a new concept for control and performance assessment of compressed air energy storage (CAES systems in a hybrid energy system is introduced. The proposed criterion, based on the concept of energy harvest index (HEI, measures the capability of a storage system to capture renewable energy. The overall efficiency of the CAES system and optimum control and design from the technical and economic point of view is presented. A possible application of this idea is an isolated community with significant wind energy resource. A case study reveals the usefulness of the proposed criterion in design, control and implementation of a small CAES system in a hybrid power system (HPM for an isolated community. Energy harvested index and its effectiveness in increasing the wind penetration rate in the total energy production is discussed.

Experimental studies of the air hybrid engine charging operation

OpenAIRE

Zhao, H; Ma, T; Lee, CY

2014-01-01

Over the last few years, theoretical and modelling studies have been carried out on the feasibility and potential of novel mild air hybrid engine concepts based on production components. These mild air hybrid concepts are able to convert vehicle brake energy into pneumatic energy in the form of compressed air stored in the air tank. The compressed air can then be used to crank-start the engine by either injecting and expanding in the cylinder or driving a production air starter. Thus, the reg...

Study of applying a hybrid standalone wind-photovoltaic generation system

Directory of Open Access Journals (Sweden)

Aissa Dahmani

2015-01-01

Full Text Available The purpose of this paper is the study of applying a hybrid system wind/photovoltaic to supply a community in southern Algeria. Diesel generators are always used to provide such remote regions with energy. Using renewable energy resources is a good alternative to overcome such pollutant generators. Hybrid Optimization Model for Electric Renewable (HOMER software is used to determine the economic feasibility of the proposed configuration. Assessment of renewable resources consisting in wind and solar potentials, load profile determination and sensitivity of different parameters analysis were performed. The cost of energy (COE of 0.226 $/kWh is very competitive with those found in literature.

Cost of electricity generated and fuel saving of an optimized wind-diesel electricity supply for village in Tangier-area (Morocco)

International Nuclear Information System (INIS)

Nfaoui, H.; Buret, J.

1996-01-01

In several of the remote areas of Morocco, diesel generators are used to provide electrical power. Such systems are often characterized by poor efficiency and high maintenance costs. The integration of wind turbine with a diesel/battery hybrid system is becoming cost-effective in wind locations. In previous works (Nfaoul et al, 1990, 1994a, 1994b), the wind characteristics in Tangier-area were studied on the basis of 12 years (1978-1989) of hourly average wind speed data. A wind/diesel energy system with battery storage has been modelled using the Tangiers wind regime over a one year period (1989), and synthesized consumer load data based on the characteristics of typical usage of domestic appliances, along with the estimated working patterns of a local isolated community. In this work, we use a more realistic hourly consumer load, which is the result of an experiment realized in a Maroccan village using a diesel engine to provide electricity for lighting and audio-visual. The 1989 wind data were reworked for a large series of measurements (12 years). The optimum wind turbine size and the benefits of a storage system on fuel saving are also reviewed. This work is concerned with diesel fuel consumption: an optimum design of the considered system is to be found which minimises the cost energy generation over the equipments' lifetime. Given the economic assumption made (the most important being a fuel price of 4.5 Dh/litre and an interest rate of 5% net of inflation), the wind/diesel energy system has been shown to be competitive with diesel-only generation in the wind regime of the Tangier location for the cost per unit wind turbine swept area less than 3000 Dh/m 2 (8Dh=1$). (author)

Performance analysis of hybrid photovoltaic/diesel energy system under Malaysian conditions

International Nuclear Information System (INIS)

Lau, K.Y.; Yousof, M.F.M.; Arshad, S.N.M.; Anwari, M.; Yatim, A.H.M.

2010-01-01

Standalone diesel generating system utilized in remote areas has long been practiced in Malaysia. Due to highly fluctuating diesel price, such a system is seemed to be uneconomical, especially in the long run if the supply of electricity for rural areas solely depends on such diesel generating system. This paper would analyze the potential use of hybrid photovoltaic (PV)/diesel energy system in remote locations. National Renewable Energy Laboratory's (NREL) HOMER software was used to perform the techno-economic feasibility of hybrid PV/diesel energy system. The investigation demonstrated the impact of PV penetration and battery storage on energy production, cost of energy and number of operational hours of diesel generators for the given hybrid configurations. Emphasis has also been placed on percentage fuel savings and reduction in carbon emissions of different hybrid systems. At the end of this paper, suitability of utilizing hybrid PV/diesel energy system over standalone diesel system would be discussed mainly based on different solar irradiances and diesel prices. (author)

Uniaxial compression tests on diesel contaminated frozen silty soil specimens

International Nuclear Information System (INIS)

Chenaf, D.; Stampli, N.; Bathurst, R.; Chapuis, R.P.

1999-01-01

Results of a uniaxial, unconfined compression test on artificial diesel-contaminated and uncontaminated frozen silty soils are discussed. The testing program involved 59 specimens. The results show that for the same fluid content, diesel contamination reduced the strength of the frozen specimens by increasing the unfrozen water content. For example, in specimens containing 50 per cent diesel oil of the fluid content by weight the maximum strength was reduced by 95 per cent compared to the strength of an uncontaminated specimen. Diesel contamination was also shown to contribute to the slippage between soil particles by acting as a lubricant, thus accelerating the loss of compressive strength.13 refs., 18 figs

Modelling and automatic reactive power control of isolated wind-diesel hybrid power systems using ANN

International Nuclear Information System (INIS)

Bansal, R.C.

2008-01-01

This paper presents an artificial neural network (ANN) based approach to tune the parameters of the static var compensator (SVC) reactive power controller over a wide range of typical load model parameters. The gains of PI (proportional integral) based SVC are optimised for typical values of the load voltage characteristics (n q ) by conventional techniques. Using the generated data, the method of multi-layer feed forward ANN with error back propagation training is employed to tune the parameters of the SVC. An ANN tuned SVC controller has been applied to control the reactive power of a variable slip/speed isolated wind-diesel hybrid power system. It is observed that the maximum deviations of all parameters are more for larger values of n q . It has been shown that initially synchronous generator supplies the reactive power required by the induction generator and/or load, and the latter reactive power is purely supplied by the SVC

Modelling and automatic reactive power control of isolated wind-diesel hybrid power systems using ANN

Energy Technology Data Exchange (ETDEWEB)

Bansal, R.C. [Electrical and Electronics Engineering Division, School of Engineering and Physics, The University of the South Pacific, Suva (Fiji)

2008-02-15

This paper presents an artificial neural network (ANN) based approach to tune the parameters of the static var compensator (SVC) reactive power controller over a wide range of typical load model parameters. The gains of PI (proportional integral) based SVC are optimised for typical values of the load voltage characteristics (n{sub q}) by conventional techniques. Using the generated data, the method of multi-layer feed forward ANN with error back propagation training is employed to tune the parameters of the SVC. An ANN tuned SVC controller has been applied to control the reactive power of a variable slip/speed isolated wind-diesel hybrid power system. It is observed that the maximum deviations of all parameters are more for larger values of n{sub q}. It has been shown that initially synchronous generator supplies the reactive power required by the induction generator and/or load, and the latter reactive power is purely supplied by the SVC. (author)

Economic Efficiency Assessment of Autonomous Wind/Diesel/Hydrogen Systems in Russia

Directory of Open Access Journals (Sweden)

O. V. Marchenko

2013-01-01

Full Text Available The economic efficiency of harnessing wind energy in the autonomous power systems of Russia is analyzed. Wind turbines are shown to be competitive for many considered variants (groups of consumers, placement areas, and climatic and meteorological conditions. The authors study the possibility of storing energy in the form of hydrogen in the autonomous wind/diesel/hydrogen power systems that include wind turbines, diesel generator, electrolyzer, hydrogen tank, and fuel cells. The paper presents the zones of economic efficiency of the system (set of parameters that provide its competitiveness depending on load, fuel price, and long-term average annual wind speed. At low wind speed and low price of fuel, it is reasonable to use only diesel generator to supply power to consumers. When the fuel price and wind speed increase, first it becomes more economical to use a wind-diesel system and then wind turbines with a hydrogen system. In the latter case, according to the optimization results, diesel generator is excluded from the system.

Power Quality Improvements in Wind Diesel Power Generation System

Directory of Open Access Journals (Sweden)

Omar Feddaoui

2015-08-01

Full Text Available Generation of electricity using diesel is costly for small remote isolated communities. At remote location electricity generation from renewable energy such as wind can help reduce the overall operating costs by reducing the fuel costs. However, the penetration of wind power into small diesel-based grids is limited because of its effect on power quality and reliability. This paper focuses on the combination of Wind Turbine and Diesel Generator systems for sustained power generation, to improve the power quality of wind generation system. The performances of the optimal control structure are assessed and discussed by means of a set of simulations.

Integrated sizing and scheduling of wind/PV/diesel/battery isolated systems

KAUST Repository

Malheiro, André

2015-05-22

In this paper we address the optimal sizing and scheduling of isolated hybrid systems using an optimization framework. The hybrid system features wind and photovoltaic conversion systems, batteries and diesel backup generators to supply electricity demand. A Mixed-Integer Linear Programming formulation is used to model system behavior over a time horizon of one year, considering hourly changes in both the availability of renewable resources and energy demand. The optimal solution is achieved with respect to the minimization of the levelized cost of energy (LCOE) over a lifetime of 20 years. Results for a case study show that the most economical solution features all four postulated subsystems. © 2015 Elsevier Ltd.

Integrated sizing and scheduling of wind/PV/diesel/battery isolated systems

KAUST Repository

Malheiro, André ; Castro, Pedro M.; Lima, Ricardo; Estanqueiro, Ana; Estanqueiro, Ana

2015-01-01

In this paper we address the optimal sizing and scheduling of isolated hybrid systems using an optimization framework. The hybrid system features wind and photovoltaic conversion systems, batteries and diesel backup generators to supply electricity demand. A Mixed-Integer Linear Programming formulation is used to model system behavior over a time horizon of one year, considering hourly changes in both the availability of renewable resources and energy demand. The optimal solution is achieved with respect to the minimization of the levelized cost of energy (LCOE) over a lifetime of 20 years. Results for a case study show that the most economical solution features all four postulated subsystems. © 2015 Elsevier Ltd.

Proposals for Enhancing Frequency Control in Weak and Isolated Power Systems: Application to the Wind-Diesel Power System of San Cristobal Island-Ecuador

Directory of Open Access Journals (Sweden)

Danny Ochoa

2018-04-01

Full Text Available Wind-diesel hybridization has been emerging as common practice for electricity generation in many isolated power systems due to its reliability and its contribution in mitigating environmental issues. However, the weakness of these kind of power systems (due to their small inertia makes the frequency regulation difficult, particularly under high wind conditions, since part of the synchronous generation has to be set offline for ensuring a suitable tracking of the power demand. This reduces the power system’s ability to absorb wind power variations, leading to pronounced grid frequency fluctuations under normal operating conditions. This paper proposes some corrective actions aimed at enhancing the frequency control capability in weak and isolated power systems: a procedure for evaluating the system stability margin intended for readjusting the diesel-generator control gains, a new wind power curtailment strategy, and an inertial control algorithm implemented in the wind turbines. These proposals are tested in the San Cristobal (Galapagos Islands-Ecuador hybrid wind-diesel power system, in which many power outages caused by frequency relays tripping were reported during the windiest season. The proposals benefits have been tested in a simulation environment by considering actual operating conditions based on measurement data recorded at the island.

Analysis of a novel autonomous marine hybrid power generation/energy storage system with a high-voltage direct current link

DEFF Research Database (Denmark)

Wang, L.; Lee, D. J.; Lee, W. J.

2008-01-01

wind turbines andWells turbines to respectively capture wind energy and wave energy from marine wind and oceanwave. In addition to wind-turbine generators(WTGs) andwave-energy turbine generators (WETGs) employed in the studied system, diesel-engine generators (DEGs) and an aqua electrolyzer (AE......This paper presents both time-domain and frequency-domain simulated results of a novel marine hybrid renewable-energy power generation/energy storage system (PG/ESS) feeding isolated loads through an high-voltage direct current (HVDC) link. The studied marine PG subsystems comprise both offshore......) absorbing a part of generated energy from WTGs and WETGs to generate available hydrogen for fuel cells (FCs) are also included in the PG subsystems. The ES subsystems consist of a flywheel energy storage system(FESS) and a compressed air energy storage (CAES) system to balance the required energy...

30 CFR 75.1730 - Compressed air; general; compressed air systems.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air; general; compressed air systems... Compressed air; general; compressed air systems. (a) All pressure vessels shall be constructed, installed... Safety and Health district office. (b) Compressors and compressed-air receivers shall be equipped with...

Smoothing of Grid-connected Wind-Diesel Power Output Using Energy Capacitor System

Directory of Open Access Journals (Sweden)

Adel A. Elbaset

2014-06-01

Full Text Available This paper presents a small hybrid power system consists of two types of power generation; wind turbine and diesel generation, DG connected to power distribution system. The fluctuations like random nature of wind power, turbulent wind, and sudden changes in load demand create imbalances in power distribution that can affect the frequency and the voltage in the power system. So, addition of Energy capacitor System, ECS is useful for compensation of fluctuating power, since it is capable of controlling both active and reactive power simultaneously and can smooth the output power flow. Hence, this paper proposes herein a dynamic model and simulation of a grid connected wind/DG based-ECS with power flow controllers between load and generation. Moreover, the paper presents a study to analyze the leveling of output fluctuation of wind power with the installation of ECS. To control the power exchanged between the ECS system and the AC grid, a load Following Control, LFC based supervisor is proposed with the aim to minimize variations of the power generated by the diesel generator. The interesting performance of the proposed supervisor is shown with the help of simulations. The computer simulation program is confirmed on a realistic circuit model which implemented in the Simulink environment of Matlab and works as if on line.

Hybrid winding concept for toroids

DEFF Research Database (Denmark)

Schneider, Henrik; Andersen, Thomas; Knott, Arnold

2013-01-01

and placement machinery. This opens up the possibility for both an automated manufacturing process and an automated production process of toroidal magnetics such as power inductors, filtering inductors, air core inductors, transformers etc. Both the proposed hybrid and the common wire wound winding...

Gasoline hybrid pneumatic engine for efficient vehicle powertrain hybridization

OpenAIRE

Dimitrova, Zlatina; Maréchal, François

2015-01-01

The largest applied convertors in passenger cars are the internal combustion engines – gasoline, diesel, adapted also for operating on alternative fuels and hybrid modes. The number of components that are necessary to realize modern future propulsion system is inexorably increasing. The need for efficiency improvement of the vehicle energy system induces the search for an innovative methodology during the design process. In this article the compressed air is investigated as an innovative solu...

Economics of compressed air energy storage to integrate wind power: A case study in ERCOT

Energy Technology Data Exchange (ETDEWEB)

Fertig, Emily, E-mail: efertig@andrew.cmu.ed [Carnegie Mellon Electricity Industry Center, Department of Engineering and Public Policy and Tepper School of Business, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States); Apt, Jay [Carnegie Mellon Electricity Industry Center, Department of Engineering and Public Policy and Tepper School of Business, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, PA 15213 (United States)

2011-05-15

Compressed air energy storage (CAES) could be paired with a wind farm to provide firm, dispatchable baseload power, or serve as a peaking plant and capture upswings in electricity prices. We present a firm-level engineering-economic analysis of a wind/CAES system with a wind farm in central Texas, load in either Dallas or Houston, and a CAES plant whose location is profit-optimized. With 2008 hourly prices and load in Houston, the economically optimal CAES expander capacity is unrealistically large - 24 GW - and dispatches for only a few hours per week when prices are highest; a price cap and capacity payment likewise results in a large (17 GW) profit-maximizing CAES expander. Under all other scenarios considered the CAES plant is unprofitable. Using 2008 data, a baseload wind/CAES system is less profitable than a natural gas combined cycle (NGCC) plant at carbon prices less than $56/tCO{sub 2} ($15/MMBTU gas) to $230/tCO{sub 2} ($5/MMBTU gas). Entering regulation markets raises profit only slightly. Social benefits of CAES paired with wind include avoided construction of new generation capacity, improved air quality during peak times, and increased economic surplus, but may not outweigh the private cost of the CAES system nor justify a subsidy. - Research highlights: {yields} Sizes of CAES and transmission paired with a Texas wind farm are optimized for profit. {yields} A profit-maximizing wind farm owner would not invest in a dedicated CAES system. {yields} The social benefit of a wind/CAES system is unlikely to outweigh private cost. {yields} CAES cannot cost-effectively smooth wind power with plausible imminent carbon prices.

Economics of compressed air energy storage to integrate wind power: A case study in ERCOT

International Nuclear Information System (INIS)

Fertig, Emily; Apt, Jay

2011-01-01

Compressed air energy storage (CAES) could be paired with a wind farm to provide firm, dispatchable baseload power, or serve as a peaking plant and capture upswings in electricity prices. We present a firm-level engineering-economic analysis of a wind/CAES system with a wind farm in central Texas, load in either Dallas or Houston, and a CAES plant whose location is profit-optimized. With 2008 hourly prices and load in Houston, the economically optimal CAES expander capacity is unrealistically large - 24 GW - and dispatches for only a few hours per week when prices are highest; a price cap and capacity payment likewise results in a large (17 GW) profit-maximizing CAES expander. Under all other scenarios considered the CAES plant is unprofitable. Using 2008 data, a baseload wind/CAES system is less profitable than a natural gas combined cycle (NGCC) plant at carbon prices less than $56/tCO 2 ($15/MMBTU gas) to $230/tCO 2 ($5/MMBTU gas). Entering regulation markets raises profit only slightly. Social benefits of CAES paired with wind include avoided construction of new generation capacity, improved air quality during peak times, and increased economic surplus, but may not outweigh the private cost of the CAES system nor justify a subsidy. - Research highlights: → Sizes of CAES and transmission paired with a Texas wind farm are optimized for profit. → A profit-maximizing wind farm owner would not invest in a dedicated CAES system. → The social benefit of a wind/CAES system is unlikely to outweigh private cost. → CAES cannot cost-effectively smooth wind power with plausible imminent carbon prices.

Wind/Hybrid Electricity Applications

Energy Technology Data Exchange (ETDEWEB)

McDaniel, Lori [Iowa Department of Natural Resources, Des Moines, IA (United States)

2001-03-01

Wind energy is widely recognized as the most efficient and cost effective form of new renewable energy available in the Midwest. New utility-scale wind farms (arrays of large turbines in high wind areas producing sufficient energy to serve thousands of homes) rival the cost of building new conventional forms of combustion energy plants, gas, diesel and coal power plants. Wind energy is not subject to the inflationary cost of fossil fuels. Wind energy can also be very attractive to residential and commercial electric customers in high wind areas who would like to be more self-sufficient for their energy needs. And wind energy is friendly to the environment at a time when there is increasing concern about pollution and climate change. However, wind energy is an intermittent source of power. Most wind turbines start producing small amounts of electricity at about 8-10 mph (4 meters per second) of wind speed. The turbine does not reach its rated output until the wind reaches about 26-28 mph (12 m/s). So what do you do for power when the output of the wind turbine is not sufficient to meet the demand for energy? This paper will discuss wind hybrid technology options that mix wind with other power sources and storage devices to help solve this problem. This will be done on a variety of scales on the impact of wind energy on the utility system as a whole, and on the commercial and small-scale residential applications. The average cost and cost-benefit of each application along with references to manufacturers will be given. Emerging technologies that promise to shape the future of renewable energy will be explored as well.

A Low Cost Air Hybrid Concept Un concept hybride à air et à bas prix

Directory of Open Access Journals (Sweden)

Lee C. Y.

2010-02-01

Full Text Available The air hybrid engine absorbs the vehicle kinetic energy during braking, stores it in an air tank in the form of compressed air, and reuses it to propel a vehicle during cruising and acceleration. Capturing, storing and reusing this braking energy to give additional power can therefore improve fuel economy, particularly in cities and urban areas where the traffic conditions involve many stops and starts. In order to reuse the residual kinetic energy, the vehicle operation consists of 3 basic modes, i.e. Compression Mode (CM, Expander Mode (EM and normal firing mode. Unlike previous works, a low cost air hybrid engine has been proposed and studied. The hybrid engine operation can be realized by means of production technologies, such as VVT and valve deactivation. In this work, systematic investigation has been carried out on the performance of the hybrid engine concept through detailed gas dynamic modelling using Ricardo WAVE software. Valve timing optimization has been done for the more efficient operation of air hybrid operation and obtaining higher braking and motoring mean effective pressure for CM and EM respectively. Le moteur hybride à air absorbe l’énergie cinétique du véhicule en cas de freinage, la stocke sous forme d’air comprimé, puis la réutilise pour faire avancer le véhicule en circulation ou en accélération. Capter, stocker et réutiliser cette énergie et créer ainsi une puissance plus importante peut donc permettre de plus grandes économies de carburant, surtout en ville et zone urbaine, lorsque les conditions de circulation imposent de nombreux arrêts et démarrages. Pour pouvoir réutiliser l’énergie cinétique, on distingue trois modes de base d’utilisation du véhicule : les modes compression (MC, expansion (ME et standard. Un moteur hybride à air et à bas prix a été proposé et étudié. Un tel moteur peut être opéré par le biais de technologies de production, comme le VVT et la d

Dual mode linguistic hedge fuzzy logic controller for an isolated wind-diesel hybrid power system with superconducting magnetic energy storage unit

International Nuclear Information System (INIS)

Thameem Ansari, M.Md.; Velusami, S.

2010-01-01

A design of dual mode linguistic hedge fuzzy logic controller for an isolated wind-diesel hybrid power system with superconducting magnetic energy storage unit is proposed in this paper. The design methodology of dual mode linguistic hedge fuzzy logic controller is a hybrid model based on the concepts of linguistic hedges and hybrid genetic algorithm-simulated annealing algorithms. The linguistic hedge operators are used to adjust the shape of the system membership functions dynamically and can speed up the control result to fit the system demand. The hybrid genetic algorithm-simulated annealing algorithm is adopted to search the optimal linguistic hedge combination in the linguistic hedge module. Dual mode concept is also incorporated in the proposed controller because it can improve the system performance. The system with the proposed controller was simulated and the frequency deviation resulting from a step load disturbance is presented. The comparison of the proportional plus integral controller, fuzzy logic controller and the proposed dual mode linguistic hedge fuzzy logic controller shows that, with the application of the proposed controller, the system performance is improved significantly. The proposed controller is also found to be less sensitive to the changes in the parameters of the system and also robust under different operating modes of the hybrid power system.

30 CFR 250.510 - Diesel engine air intakes.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.510 Section 250... engine air intakes. Diesel engine air intakes must be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines that are continuously attended must be equipped with...

Analysis on a hybrid desiccant air-conditioning system

International Nuclear Information System (INIS)

Jia, C.X.; Dai, Y.J.; Wu, J.Y.; Wang, R.Z.

2006-01-01

Hybrid desiccant-assisted preconditioner and split cooling coil system, which combines the merits of moisture removal by desiccant and cooling coil for sensible heat removal, is a potential alternative to conventional vapor compression cooling systems. In this paper, experiments on a hybrid desiccant air-conditioning system, which is actually an integration of a rotary solid desiccant dehumidification and a vapor compression air-conditioning unit, had been carried out. It is found that, compared with the conventional VC (vapor compression) system, the hybrid desiccant cooling system economizes 37.5% electricity powers when the process air temperature and relative humidity are maintained at 30 o C, and 55% respectively. The reason why the hybrid desiccant cooling system features better performance relative to the VC system lies in the improvement brought about in the performance of the evaporator in VC unit due to desiccant dehumidification. A thermodynamic model of the hybrid desiccant system with R-22 as the refrigerant has been developed and the impact of operating parameters on the sensible heat ratio of the evaporator and the electric power saving rate has been analyzed. It is found that a majority of evaporators can operate in the dry condition even if the regeneration temperature is lower (i.e. 80 o C)

Combustion characteristics of compressed natural gas/diesel dual-fuel turbocharged compressed ignition engine

Energy Technology Data Exchange (ETDEWEB)

Shenghua, L.; Longbao, Z.; Ziyan, W.; Jiang, R. [Xi' an Jiaotong Univ. (China). Dept. of Automotive Engineering

2003-09-01

The combustion characteristics of a turbocharged natural gas and diesel dual-fuelled compression ignition (CI) engine are investigated. With the measured cylinder pressures of the engine operated on pure diesel and dual fuel, the ignition delay, effects of pilot diesel and engine load on combustion characteristics are analysed. Emissions of HC, CO, NO{sub x} and smoke are measured and studied too. The results show that the quantity of pilot diesel has important effects on the performance and emissions of a dual-fuel engine at low-load operating conditions. Ignition delay varies with the concentration of natural gas. Smoke is much lower for the developed dual-fuel engine under all the operating conditions. (Author)

30 CFR 250.610 - Diesel engine air intakes.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Diesel engine air intakes. 250.610 Section 250... engine air intakes. No later than May 31, 1989, diesel engine air intakes shall be equipped with a device to shut down the diesel engine in the event of runaway. Diesel engines which are continuously...

Analysis of a diesel-electric hybrid urban bus system

Science.gov (United States)

Marr, W. W.; Sekar, R. R.; Ahlheim, M. C.

A hybrid bus powered by a diesel engine and a battery pack was analyzed over an idealized bus-driving cycle in Chicago. Three hybrid configurations, two parallel and one series, were evaluated. The results indicate that the fuel economy of a hybrid bus, taking into account the regenerative braking, is comparable with that of a conventional diesel bus. Life-cycle costs are slightly higher because of the added weight and cost of the battery.

A comparative experimental study on engine operating on premixed charge compression ignition and compression ignition mode

Directory of Open Access Journals (Sweden)

Bhiogade Girish E.

2017-01-01

Full Text Available New combustion concepts have been recently developed with the purpose to tackle the problem of high emissions level of traditional direct injection Diesel engines. A good example is the premixed charge compression ignition combustion. A strategy in which early injection is used causing a burning process in which the fuel burns in the premixed condition. In compression ignition engines, soot (particulate matter and NOx emissions are an extremely unsolved issue. Premixed charge compression ignition is one of the most promising solutions that combine the advantages of both spark ignition and compression ignition combustion modes. It gives thermal efficiency close to the compression ignition engines and resolves the associated issues of high NOx and particulate matter, simultaneously. Premixing of air and fuel preparation is the challenging part to achieve premixed charge compression ignition combustion. In the present experimental study a diesel vaporizer is used to achieve premixed charge compression ignition combustion. A vaporized diesel fuel was mixed with the air to form premixed charge and inducted into the cylinder during the intake stroke. Low diesel volatility remains the main obstacle in preparing premixed air-fuel mixture. Exhaust gas re-circulation can be used to control the rate of heat release. The objective of this study is to reduce exhaust emission levels with maintaining thermal efficiency close to compression ignition engine.

Techno-economic feasibility of hybrid diesel/PV/wind/battery electricity generation systems for non-residential large electricity consumers under southern Iran climate conditions

International Nuclear Information System (INIS)

Baneshi, Mehdi; Hadianfard, Farhad

2016-01-01

Highlights: • A hybrid electricity generation system for a large electricity consumer was studied. • The PV and wind electricity potentials under given climate conditions were evaluated. • Technical, economical, and environmental issues of different systems were discussed. • The optimum configuration of components was obtained. • The impacts of governmental incentives on economic viability of systems were examined. - Abstract: This paper aims to study the techno-economical parameters of a hybrid diesel/PV/wind/battery power generation system for a non-residential large electricity consumer in the south of Iran. As a case study, the feasibility of running a hybrid system to meet a non-residential community’s load demand of 9911 kWh daily average and 725 kW peak load demand was investigated. HOMER Pro software was used to model the operation of the system and to identify the appropriate configuration of it based on comparative technical, economical, and environmental analysis. Both stand alone and grid connected systems were modeled. The impacts of annual load growth and governmental energy policies such as providing low interest loan to renewable energy projects, carbon tax, and modifying the grid electricity price on viability of the system were discussed. Results show that for off-grid systems the cost of electricity (COE) and the renewable fraction of 9.3–12.6 ₵/kWh and 0–43.9%, respectively, are achieved with photovoltaic (PV) panel, wind turbine, and battery sizes of 0–1000 kW, 0–600 kW, and 1300 kWh, respectively. For on grid systems without battery storage the range of COE and renewable fraction are 5.7–8.4 ₵/kWh and 0–53%, respectively, for the same sizes of PV panel and wind turbine.

Energy savings potential of a hybrid desiccant dehumidification air conditioning system in Beirut

International Nuclear Information System (INIS)

Ghali, Kamel

2008-01-01

In this work, the transient performance of a hybrid desiccant vapor compression air conditioning system is numerically simulated for the ambient conditions of Beirut. The main feature of this hybrid system is that the regenerative heat needed by the desiccant wheel is partly supplied by the condenser dissipated heat while the rest is supplied by an auxiliary gas heater. The hybrid air conditioning system of the present study replaces a 23 kW vapor compression unit for a typical office in Beirut characterized by a high latent load. The vapor compression subsystem size in the hybrid air conditioning system is reduced to 15 kW at the peak load when the regeneration temperature was fixed at 75 deg. C. Also the sensible heat ratio of the combined hybrid system increased from 0.47 to 0.73. Based on hour by hour simulation studies for a wide range of recorded ambient conditions of Beirut city, this paper predicts the annual energy consumption of the hybrid system in comparison with the conventional vapor compression system for the entire cooling season. The annual running costs savings for the hybrid system is 418.39 USD for a gas cost price of 0.141 USD/kg. The pay back period of the hybrid system is less than five years when the initial cost of the hybrid air conditioning system priced an additional 1712.00 USD. Hence, for a 20-year life cycle, the life cycle savings of the hybrid air conditioning system are 4295.19 USD

Modeling and optimization of batteryless hybrid PV (photovoltaic)/Diesel systems for off-grid applications

International Nuclear Information System (INIS)

Tsuanyo, David; Azoumah, Yao; Aussel, Didier; Neveu, Pierre

2015-01-01

This paper presents a new model and optimization procedure for off-grid hybrid PV (photovoltaic)/Diesel systems operating without battery storage. The proposed technico-economic model takes into account the variability of both the solar irradiation and the electrical loads. It allows optimizing the design and the operation of the hybrid systems by searching their lowest LCOE (Levelized Cost of Electricity). Two cases have been investigated: identical Diesel generators and Diesel generators with different sizes, and both are compared to conventional standalone Diesel generator systems. For the same load profile, the optimization results show that the LCOE of the optimized batteryless hybrid solar PV/Diesel (0.289 €/kWh for the hybrid system with identical Diesel generators and 0.284 €/kWh for the hybrid system with different sizes of Diesel generators) is lower than the LCOE obtained with standalone Diesel generators (0.32 €/kWh for the both cases). The obtained results are then confirmed by HOMER (Hybrid Optimization Model for Electric Renewables) software. - Highlights: • A technico-economic model for optimal design and operation management of batteryless hybrid systems is developed. • The model allows optimizing design and operation of hybrid systems by ensuring their lowest LCOE. • The model was validated by HOMER. • Batteryless hybrid system are suitable for off-grid applications

Technology, Performance, and Market Report of Wind-Diesel Applications for Remote and Island Communities: Preprint

Energy Technology Data Exchange (ETDEWEB)

Baring-Gould, I.; Dabo, M.

2009-02-01

This paper describes the current status of wind-diesel technology and its applications, the current research activities, and the remaining system technical and commercial challenges. System architectures, dispatch strategies, and operating experience from a variety of wind-diesel systems will be discussed, as well as how recent development to explore distributed energy generation solutions for wind generation can benefit from the performance experience of operating systems. The paper also includes a detailed discussion of the performance of wind-diesel applications in Alaska, where 10 wind-diesel stations are operating and additional systems are currently being implemented. Additionally, because this application represents an international opportunity, a community of interest committed to sharing technical and operating developments is being formed. The authors hope to encourage this expansion while allowing communities and nations to investigate the wind-diesel option for reducing their dependence on diesel-driven energy sources.

Technology, Performance, and Market Report of Wind-Diesel Applications for Remote and Island Communities: Preprint

Energy Technology Data Exchange (ETDEWEB)

Baring-Gould, I.; Dabo, M.

2009-05-01

This paper describes the current status of wind-diesel technology and its applications, the current research activities, and the remaining system technical and commercial challenges. System architectures, dispatch strategies, and operating experience from a variety of wind-diesel systems will be discussed, as well as how recent development to explore distributed energy generation solutions for wind generation can benefit from the performance experience of operating systems. The paper also includes a detailed discussion of the performance of wind-diesel applications in Alaska, where 10 wind-diesel stations are operating and additional systems are currently being implemented. Additionally, because this application represents an international opportunity, a community of interest committed to sharing technical and operating developments is being formed. The authors hope to encourage this expansion while allowing communities and nations to investigate the wind-diesel option for reducing their dependence on diesel-driven energy sources.

A hybrid reconfigurable solar and wind energy system

Science.gov (United States)

Gadkari, Sagar A.

We study the feasibility of a novel hybrid solar-wind hybrid system that shares most of its infrastructure and components. During periods of clear sunny days the system will generate electricity from the sun using a parabolic concentrator. The concentrator is formed by individual mirror elements and focuses the light onto high intensity vertical multi-junction (VMJ) cells. During periods of high wind speeds and at night, the same concentrator setup will be reconfigured to channel the wind into a wind turbine which will be used to harness wind energy. In this study we report on the feasibility of this type of solar/wind hybrid energy system. The key mechanisms; optics, cooling mechanism of VMJ cells and air flow through the system were investigated using simulation tools. The results from these simulations, along with a simple economic analysis giving the levelized cost of energy for such a system are presented. An iterative method of design refinement based on the simulation results was used to work towards a prototype design. The levelized cost of the system achieved in the economic analysis shows the system to be a good alternative for a grid isolated site and could be used as a standalone system in regions of lower demand. The new approach to solar wind hybrid system reported herein will pave way for newer generation of hybrid systems that share common infrastructure in addition to the storage and distribution of energy.

Feasibility of Hybrid Retrofits to Off-Grid Diesel Power Plants in the Philippines

International Nuclear Information System (INIS)

Abergas, R.L.; Barley, C.D.; Barruela, R.B.

1999-01-01

The Strategic Power Utilities Group (SPUG) of the National Power Corporation (NPC) in the Philippines owns and operates about 100 power plants, mostly fueled by diesel, ranging in energy production from about 15 kilowatt-hours (kWh)/day to 106,000 kWh/day. Reducing the consumption of diesel fuel in these plants, along with the associated financial losses, is a priority for SPUG. The purpose of this study is to estimate the potential fuel and cost savings that might be achieved by retrofitting hybrid power systems to these existing diesel plants. As used in this report, the term ''hybrid system'' refers to any combination of wind turbine generators (WTGs), photovoltaic (PV) modules, lead-acid batteries, and an AC/DC power converter (either an electronic inverter or a rotary converter), in addition to the existing diesel gensets. The resources available for this study did not permit a detailed design analysis for each of the plants. Instead, the following five-step process was used: 1.Tabulate some important characteristics of all the plants. 2.Group the plants into categories (six classes) with similar characteristics. 3.For each class of system, identify one plant that is representative of the class. 4.For each representative plant, perform a moderately detailed prefeasibility analysis of design options. 5.Summarize and interpret the results. The analysis of each representative plant involved the use of time-series computer simulation models to estimate the fuel usage, maintenance expenses, and cash flow resulting from various designs, and to search the domain of possible designs for the one leading to the lowest life-cycle cost. Cost items that would be unaffected by the retrofit, such as operator salaries and the capital cost of existing equipment, were not included in the analysis. Thus, the results are reported as levelized cost of energy (COE) savings: the difference between the cost of the existing diesel-only system and that of an optimized hybrid system

Experimental and Numerical Study of Jet Controlled Compression Ignition on Combustion Phasing Control in Diesel Premixed Compression Ignition Systems

OpenAIRE

Qiang Zhang; Wuqiang Long; Jiangping Tian; Yicong Wang; Xiangyu Meng

2014-01-01

In order to directly control the premixed combustion phasing, a Jet Controlled Compression Ignition (JCCI) for diesel premixed compression ignition systems is investigated. Experiments were conducted on a single cylinder natural aspirated diesel engine without EGR at 3000 rpm. Numerical models were validated by load sweep experiments at fixed spark timing. Detailed combustion characteristics were analyzed based on the BMEP of 2.18 bar. The simulation results showed that the high temperature j...

THE EFFECTS OF INCREASE THE COMPRESSION RATIO ON PERFORMANCE OF A DIESEL ENGINE

Directory of Open Access Journals (Sweden)

Adnan PARLAK

2003-02-01

Full Text Available An optimisation of the Diesel cycle has been performed for power output and thermal efficiency with respect to compression ratio for various extreme temperature ratio. The relation between compression ratio and extreme temperature ratio, which gives optimum performance is derived. As the compression ratio of the diesel engine is increased in comparison to the optimum value of the engine, it is shown that the performance of the engine is decreased. The experimental study agrees with these results. In this study, compression ratio of a single cylinder pre-combustion chamber variable compression ratio Ricardo E6 type engine with the optimum compression ratio of 18.20 was increased to 19.60. As a results of this increase, specific fuel consumption was increased about 8 % and brake thermal efficiency was decreased about 7.5 %.

Hybrid technologies for the remediation of Diesel fuel polluted soil

Energy Technology Data Exchange (ETDEWEB)

Pazos, M.; Alcantara, M.T.; Rosales, E.; Sanroman, M.A. [Department of Chemical Engineering, University of Vigo (Spain)

2011-12-15

Diesel fuel may be released into soil due to anthropogenic activities, such as accidental spills or leaks in underground storage tanks or pipelines. Since diesel fuel is mainly composed of hydrophobic organic compounds, it has low water solubility. Therefore, treating contaminated areas with conventional techniques is difficult. In this study, electrokinetic treatment of soil contaminated with diesel fuel was carried out. Two different hybrid approaches to pollutant removal were tested. A surfactant was used as a processing fluid during electrokinetic treatment to increase desorption and the solubility of diesel fuel. Additionally, a hybrid technology combining a Fenton reaction and electrokinetic remediation (EK-Fenton) was tested in an attempt to generate favorable in situ degradation of pollutants. The efficiency of each treatment was determined based on diesel fuel removal. After 30 days of treatment, the highest removal of diesel fuel was found to be achieved with the EK-Fenton process. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Performance and emission of generator Diesel engine using methyl esters of palm oil and diesel blends at different compression ratio

Science.gov (United States)

Aldhaidhawi, M.; Chiriac, R.; Bădescu, V.; Pop, H.; Apostol, V.; Dobrovicescu, A.; Prisecaru, M.; Alfaryjat, A. A.; Ghilvacs, M.; Alexandru, A.

2016-08-01

This study proposes engine model to predicate the performance and exhaust gas emissions of a single cylinder four stroke direct injection engine which was fuelled with diesel and palm oil methyl ester of B7 (blends 7% palm oil methyl ester with 93% diesel by volume) and B10. The experiment was conducted at constant engine speed of 3000 rpm and different engine loads operations with compression ratios of 18:1, 20:1 and 22:1. The influence of the compression ratio and fuel typeson specific fuel consumption and brake thermal efficiency has been investigated and presented. The optimum compression ratio which yields better performance has been identified. The result from the present work confirms that biodiesel resulting from palm oil methyl ester could represent a superior alternative to diesel fuel when the engine operates with variable compression ratios. The blends, when used as fuel, result in a reduction of the brake specific fuel consumption and brake thermal efficiency, while NOx emissions was increased when the engine is operated with biodiesel blends.

FEASIBILITY STUDY AND OPTIMIZATION OF AN HYBRID SYSTEM (EOLIAN- PHOTOVOLTAIC - DIESEL WITH PROVISION OF ELECTRIC ENERGY COMPLETELY INDEPENDENT

Directory of Open Access Journals (Sweden)

D. Saheb-Koussa

2015-08-01

Full Text Available      In engineering, simulation is an effective and economical, commonly used to make preliminary or comparative studies, both during development (design and normal operation of systems. Currently, several simulation tools, using HOMER, are used in academia. Thus, in this work, we present the principle of feasibility study and optimization of a stand alone hybrid system (wind-photovoltaic-diesel. Furthermore, we determined the price per kWh of electricity supplied by the stand alone hybrid system, which amounts to $ 1417 / kWh. The site considered in this study represents the Adrar site located in the south west Algeria. Thus, we have inferred from this work as part of a configuration of the stand alone hybrid system obviously depends on available energy resources and constraints. On the other hand we have highlighted the role of the renewable energy uses in reducing emissions of greenhouse gas (CO2 rate = 16086 kg / year for a system using only the generator diesel and is 599 kg / year for the stand alone hybrid system studied.

Using a New Modification on Wind Turbine Ventilator for Improving Indoor Air Quality

Directory of Open Access Journals (Sweden)

Louay Abdul salam Rasheed

2018-02-01

Full Text Available This paper describes a newly modified wind turbine ventilator that can achieve highly efficient ventilation. The new modification on the conventional wind turbine ventilator system may be achieved by adding a Savonius wind turbine above the conventional turbine to make it work more efficiently and help spinning faster. Three models of the Savonius wind turbine with 2, 3, and 4 blades' semicircular arcs are proposed to be placed above the conventional turbine of wind ventilator to build a hybrid ventilation turbine. A prototype of room model has been constructed and the hybrid turbine is placed on the head of the room roof. Performance's tests for the hybrid turbine with a different number of blades and different values of wind speeds have been conducted. The experimental test results show that the performance of the improved ventilation turbine with three blades is the best. It is found that the maximum rotation speed of the improved turbine is 107rpm, while the air flow rate is 0.0103m3/s and the air change rate per hour is 32.67hr-1, at a wind speed of 3m/s. The proposed design has been achieved an increase in the turbine rotational speed, increase of the extraction rate of the indoor air and the air-changes per hour, provided the requisite ventilation and improved the quality of the indoor air.

BENEFITS AND CHALLENGES OF VARIABLE COMPRESSION RATIO AT DIESEL ENGINES

OpenAIRE

Radivoje B Pešić; Saša T Milojević; Stevan P Veinović

2010-01-01

The compression ratio strongly affects the working process and provides an exceptional degree of control over engine performance. In conventional internal combustion engines, the compression ratio is fixed and their performance is therefore a compromise between conflicting requirements. One fundamental problem is that drive units in the vehicles must successfully operate at variable speeds and loads and in different ambient conditions. If a diesel engine has a fixed compression ratio, a minim...

Transmission Congestion Management using a Wind Integrated Compressed Air Energy Storage System

Directory of Open Access Journals (Sweden)

S. Gope

2017-08-01

Full Text Available Transmission congestion is a vital problem in the power system security and reliability sector. To ensure the stable operation of the system, a congestion free power network is desirable. In this paper, a new Congestion Management (CM technique, the Wind integrated Compressed Air Energy Storage (WCAES system is used to alleviate transmission congestion and to minimize congestion mitigation cost. The CM problem has been solved by using the Generator Sensitivity Factor (GSF and the Bus Sensitivity Factor (BSF. BSF is used for finding the optimal location of WCAES in the system. GSF with a Moth Flame Optimization (MFO algorithm is used for rescheduling the generators to alleviate congestion and to minimize congestion cost by improving security margin. The impact of the WCAES system is tested with a 39 bus system. To validate this approach, the same problem has been solved with a Particle Swarm Optimization (PSO algorithm and the obtained results are compared with the ones from the MFO algorithm.

The economics of hybrid power systems for sustainable desert agriculture in Egypt

DEFF Research Database (Denmark)

Kamel, S.M.; Dahl, C.

2005-01-01

Egypt has embarked on an ambitious desert land reclamation program in order to increase total food production. Energy planners for these desert agriculture locations have chosen diesel generation power technology because minimization of the initial capital cost of a power supply system is their top...... priority. This heavy reliance on diesel generation has negative effects on the surrounding environment including soil, groundwater, and air pollution. Although good solar and wind resource prospects exist for the use of cleaner hybrid power systems in certain desert locations, little research has been done...... to investigate the economic potential of such systems in Egypt’s desert agriculture sector. Using optimization software, we assess the economics of hybrid power systems versus the present diesel generation technology in a remote agricultural development area. We also consider the emission reduction advantages...

Optimal Control of Hybrid Systems in Air Traffic Applications

Science.gov (United States)

Kamgarpour, Maryam

Growing concerns over the scalability of air traffic operations, air transportation fuel emissions and prices, as well as the advent of communication and sensing technologies motivate improvements to the air traffic management system. To address such improvements, in this thesis a hybrid dynamical model as an abstraction of the air traffic system is considered. Wind and hazardous weather impacts are included using a stochastic model. This thesis focuses on the design of algorithms for verification and control of hybrid and stochastic dynamical systems and the application of these algorithms to air traffic management problems. In the deterministic setting, a numerically efficient algorithm for optimal control of hybrid systems is proposed based on extensions of classical optimal control techniques. This algorithm is applied to optimize the trajectory of an Airbus 320 aircraft in the presence of wind and storms. In the stochastic setting, the verification problem of reaching a target set while avoiding obstacles (reach-avoid) is formulated as a two-player game to account for external agents' influence on system dynamics. The solution approach is applied to air traffic conflict prediction in the presence of stochastic wind. Due to the uncertainty in forecasts of the hazardous weather, and hence the unsafe regions of airspace for aircraft flight, the reach-avoid framework is extended to account for stochastic target and safe sets. This methodology is used to maximize the probability of the safety of aircraft paths through hazardous weather. Finally, the problem of modeling and optimization of arrival air traffic and runway configuration in dense airspace subject to stochastic weather data is addressed. This problem is formulated as a hybrid optimal control problem and is solved with a hierarchical approach that decouples safety and performance. As illustrated with this problem, the large scale of air traffic operations motivates future work on the efficient

Coca-Cola Refreshments Class 8 Diesel Electric Hybrid Tractor Evaluation: 13-Month Final Report

Energy Technology Data Exchange (ETDEWEB)

Walkowicz, K.; Lammert, M.; Curran, P.

2012-08-01

This 13-month evaluation used five Kenworth T370 hybrid tractors and five Freightliner M2106 standard diesel tractors at a Coca Cola Refreshments facility in Miami, Florida. The primary objective was to evaluate the fuel economy, emissions, and operational field performance of hybrid electric vehicles when compared to similar-use conventional diesel vehicles. A random dispatch system ensures the vehicles are used in a similar manner. GPS logging, fueling, and maintenance records and laboratory dynamometer testing are used to evaluate the performance of these hybrid tractors. Both groups drive similar duty cycles with similar kinetic intensity (0.95 vs. 0.69), average speed (20.6 vs. 24.3 mph), and stops per mile (1.9 vs. 1.5). The study demonstrated the hybrid group had a 13.7% fuel economy improvement over the diesel group. Laboratory fuel economy and field fuel economy study showed similar trends along the range of KI and stops per mile. Hybrid maintenance costs were 51% lower per mile; hybrid fuel costs per mile were 12% less than for the diesels; and hybrid vehicle total cost of operation per mile was 24% less than the cost of operation for the diesel group.

Wind data analysis for the design of a hybrid generation system at the Algodoal Island - Brazil

Energy Technology Data Exchange (ETDEWEB)

Bezerra, U.H.; Pinho, J.T.; J.C. da Cunha, D. de; Araujo, A.C.S. [Universidade Federal do Para (Brazil)

1997-12-31

The northeastern coast of the State of Para and the Marajo Island - in Brazil, exhibit a wind potential that seems adequate to the generation of electric energy to supply local demands. These local demands are mostly formed by small towns and villages located invariably far from the big urban centers with little or no possibility to be supplied by the utility grid. In this paper it is intended to report the studies being conducted to design a hybrid wind diesel system to attend a small population center, namely the Algodoal Island, that is a representative sample of this region. It will be described the process of data acquisition and statistical treatment as well as some environmental, social and economic aspects regarding the Algodoal Island. Finally it will be presented a preliminary estimate of energy demand for this locality as well as a probable wind-diesel system arrangement to supply this demand.

Experimental and Numerical Study of Jet Controlled Compression Ignition on Combustion Phasing Control in Diesel Premixed Compression Ignition Systems

Directory of Open Access Journals (Sweden)

Qiang Zhang

2014-07-01

Full Text Available In order to directly control the premixed combustion phasing, a Jet Controlled Compression Ignition (JCCI for diesel premixed compression ignition systems is investigated. Experiments were conducted on a single cylinder natural aspirated diesel engine without EGR at 3000 rpm. Numerical models were validated by load sweep experiments at fixed spark timing. Detailed combustion characteristics were analyzed based on the BMEP of 2.18 bar. The simulation results showed that the high temperature jets of reacting active radical species issued from the ignition chamber played an important role on the onset of combustion in the JCCI system. The combustion of diesel pre-mixtures was initiated rapidly by the combustion products issued from the ignition chamber. Moreover, the flame propagation was not obvious, similar to that in Pre-mixed Charge Compression Ignition (PCCI. Consequently, spark timing sweep experiments were conducted. The results showed a good linear relationship between spark timing in the ignition chamber and CA10 and CA50, which indicated the ability for direct combustion phasing control in diesel PCCI. The NOx and soot emissions gradually changed with the decrease of spark advance angle. The maximum reduction of NOx and soot were both over 90%, and HC and CO emissions were increased.

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XIV, I--MAINTAINING THE AIR SYSTEM, CUMMINS DIESEL ENGINE, II--UNIT REMOVAL--TRANSMISSION.

Science.gov (United States)

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATING PRINCIPLES AND MAINTENANCE OF THE DIESEL ENGINE AIR SYSTEM AND THE PROCEDURES FOR TRANSMISSION REMOVAL. TOPICS ARE (1) DEFINITION OF TERMS RELATED TO THE DIESEL AIR SYSTEM, (2) PRNCIPLES OF DIESEL AIR COMPRESSORS, (3) PRINCIPLES OF AIR STARTING MOTORS, (4)…

Techno-economical analysis of off-grid hybrid systems at Kutubdia Island, Bangladesh

International Nuclear Information System (INIS)

Kumar Nandi, Sanjoy; Ranjan Ghosh, Himangshu

2010-01-01

Kutubdia is an island in the southern coast of Bangladesh where mainland grid electricity is not present or would not feasible in near future. Presently, electricity is generated using a diesel generator by Bangladesh Power Development Board (BPDB) for a limited time and location. Due to its remote location, the fuel cost in Kutubdia is very expensive. In the present study one-year recorded wind by Bangladesh Centre of Advanced Studies (BCAS) location and other three potential locations for hybrid system analysis is discussed. The system configuration of the hybrid is achieved based on a theoretical domestic load at the island. The sizing of the hybrid power systems is discussed with 0% and 5% annual capacity of shortage. This feasibility study indicates that wind-PV-diesel system is feasible with 0% capacity of shortage and wind-diesel system is feasible with 5% annual capacity of shortage at all locations. As 5% annual capacity of shortage can be considered, the wind-diesel hybrid system will reduce net present cost as well as cost of energy to about 20% and the diesel consumption on the island can be reduced to about 50% of its present annual consumption. Such a hybrid system will reduce about 44% green house gases (GHG) from the local atmosphere.

Heavy Duty Diesel Truck and Bus Hybrid Powertrain Study

Science.gov (United States)

2012-03-01

Electric Vehicles to supply battery modules for Smith’s lineup of zero-emission, all-electric commercial vehicles (CVs). A123 expects to begin...hybrids may have generally improved reliability compared to conventional diesel vehicles, their maintenance procedures are specialized. Hybrid

An assessment of the dual-mode reactivity controlled compression ignition/conventional diesel combustion capabilities in a EURO VI medium-duty diesel engine fueled with an intermediate ethanol-gasoline blend and biodiesel

International Nuclear Information System (INIS)

Benajes, Jesús; García, Antonio; Monsalve-Serrano, Javier; Balloul, Iyad; Pradel, Gérard

2016-01-01

Highlights: • Reactivity controlled compression ignition regime utilized from 25% to 35% load. • Dual-mode reduces the regeneration periods of the diesel particulate filter. • The use of near-term available biofuels allows good performance and emissions. • Dual-mode leads to 2% greater efficiency than diesel combustion at high engine speeds. - Abstract: This work investigates the capabilities of the dual-mode reactivity controlled compression ignition/conventional diesel combustion engine operation to cover the full operating range of a EURO VI medium-duty diesel engine with compression ratio of 17.5:1. This concept is based on covering all the engine map switching between the reactivity controlled compression ignition and the conventional diesel combustion operating modes. Specifically, the benefits of reactivity controlled compression ignition combustion are exploited whenever possible according to certain restrictions, while the conventional diesel combustion operation is used to cover the zones of the engine map in which the reactivity controlled compression ignition operation is limited. The experiments were conducted using a single-cylinder research diesel engine derived from the multi-cylinder production engine. In addition, considering the mandatory presence of biofuels in the future context of road transport and the ability of ethanol to be blended with gasoline, the low reactivity fuel used in the study is a blend of 20% ethanol by volume with 80% of 95 octane number gasoline. Moreover, a diesel containing 7% of biodiesel has been used as high reactivity fuel. Firstly, a reactivity controlled compression ignition mapping is performed to check the operational limits of the concept in this engine platform. Later, based on the results, the potential of the dual-mode concept is discussed. Results suggest that, under the constraints imposed, reactivity controlled compression ignition combustion can be utilized between 25% and 35% load. In this region

Economic analysis of hybrid power systems (PV/diesel) in different climatic zones of Tamil Nadu

International Nuclear Information System (INIS)

Suresh Kumar, U.; Manoharan, P.S.

2014-01-01

Highlights: • Investigation on economic feasibility of PV/diesel system in various climatic zones. • HOMER is used to solve economic feasibility analysis. • By the sensitivity analysis, the net present cost is reduced. • Optimum climatic zone in Tamil Nadu, India is recommended. - Abstract: With the increasing threat to environment and the fast depleting fossil fuel resources, hybrid power systems consisting of two or more renewable energy sources such as solar PV, wind, biomass, ocean thermal-with or without the back up of diesel generator have come to the forefront. These hybrid systems are normally integrated with battery banks for total reliability; such systems have brought about better quality of life in remote areas of developing economics. The remote areas in the state of Tamil Nadu in India possess excellent renewable energy sources. These areas fall under different climatic zones, are sparsely populated and are in the process of development. Though these areas are connected to the grid, Tamil Nadu grid is not stable; it is currently experiencing 40% short fall in generation. Thus grid power is available to these remote areas only for 10 h a day and even when available, there are voltage frequency problems. This paper analyses the economic feasibility of installing and operating hybrid systems in these areas. The areas are divided into different climatic zones and the hybrid system economy is analyzed for each climatic zone on the basis of NPC (net present cost), consumption of diesel and renewable fraction for all climate zones. The analysis indicates that the interior climatic zone – the area would be the optimum climatic zone to install HPS PV/diesel. The sensitivity analysis proves that the NPC of such a system can be reduced. It is suggested that due to high initial cost, government subsidy is necessary to adopt the system on a large scale. Such a profit will encourage development of renewable energy utilization and bring about rapid

Studying the effect of compression ratio on an engine fueled with waste oil produced biodiesel/diesel fuel

Directory of Open Access Journals (Sweden)

Mohammed EL_Kassaby

2013-03-01

Full Text Available Wasted cooking oil from restaurants was used to produce neat (pure biodiesel through transesterification, and then used to prepare biodiesel/diesel blends. The effect of blending ratio and compression ratio on a diesel engine performance has been investigated. Emission and combustion characteristics was studded when the engine operated using the different blends (B10, B20, B30, and B50 and normal diesel fuel (B0 as well as when varying the compression ratio from 14 to 16 to 18. The result shows that the engine torque for all blends increases as the compression ratio increases. The bsfc for all blends decreases as the compression ratio increases and at all compression ratios bsfc remains higher for the higher blends as the biodiesel percent increase. The change of compression ratio from 14 to 18 resulted in, 18.39%, 27.48%, 18.5%, and 19.82% increase in brake thermal efficiency in case of B10, B20, B30, and B50 respectively. On an average, the CO2 emission increased by 14.28%, the HC emission reduced by 52%, CO emission reduced by 37.5% and NOx emission increased by 36.84% when compression ratio was increased from 14 to 18. In spite of the slightly higher viscosity and lower volatility of biodiesel, the ignition delay seems to be lower for biodiesel than for diesel. On average, the delay period decreased by 13.95% when compression ratio was increased from 14 to 18. From this study, increasing the compression ratio had more benefits with biodiesel than that with pure diesel.

User acceptance of diesel/PV hybrid system in an island community

International Nuclear Information System (INIS)

Phuangpornpitak, N.; Kumar, S.

2011-01-01

This paper presents the results of a study conducted at a rural (island) community to understand the role of PV hybrid system installed on an island. Until 2004, most islanders had installed diesel generators in their homes to generate electricity, which was directly supplied to appliances or stored in the batteries for later use. A field survey was carried out to study the user satisfaction of the PV hybrid system in the island community. The attitude of islanders to the PV hybrid system was mostly positive. The islanders can use more electricity, the supply of which can meet the demand. A comparison of pollutions before and after installation of the PV hybrid system was made along with the interviews with the users. The data show that the users are highly satisfied with the PV hybrid system which can reduce environmental impact, especially air and noise pollutions. New opportunities as a result of access to electric service include studying and reading at night that were not possible earlier. All the islanders use the PV hybrid system and more importantly, no one found that the system made their life worse as compared to the earlier state of affairs. (author)

Compressed Biogas-Diesel Dual-Fuel Engine Optimization Study for Ultralow Emission

Directory of Open Access Journals (Sweden)

Hasan Koten

2014-06-01

Full Text Available The aim of this study is to find out the optimum operating conditions in a diesel engine fueled with compressed biogas (CBG and pilot diesel dual-fuel. One-dimensional (1D and three-dimensional (3D computational fluid dynamics (CFD code and multiobjective optimization code were employed to investigate the influence of CBG-diesel dual-fuel combustion performance and exhaust emissions on a diesel engine. In this paper, 1D engine code and multiobjective optimization code were coupled and evaluated about 15000 cases to define the proper boundary conditions. In addition, selected single diesel fuel (dodecane and dual-fuel (CBG-diesel combustion modes were modeled to compare the engine performances and exhaust emission characteristics by using CFD code under various operating conditions. In optimization study, start of pilot diesel fuel injection, CBG-diesel flow rate, and engine speed were optimized and selected cases were compared using CFD code. CBG and diesel fuels were defined as leading reactants using user defined code. The results showed that significantly lower NOx emissions were emitted under dual-fuel operation for all cases compared to single-fuel mode at all engine load conditions.

University of Arizona Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Simmons, Joseph [Univ. of Arizona, Tucson, AZ (United States); Muralidharan, Krishna [Univ. of Arizona, Tucson, AZ (United States)

2012-12-31

Boiled down to its essentials, the grant’s purpose was to develop and demonstrate the viability of compressed air energy storage (CAES) for use in renewable energy development. While everyone agrees that energy storage is the key component to enable widespread adoption of renewable energy sources, the development of a viable scalable technology has been missing. The Department of Energy has focused on expanded battery research and improved forecasting, and the utilities have deployed renewable energy resources only to the extent of satisfying Renewable Portfolio Standards. The lack of dispatchability of solar and wind-based electricity generation has drastically increased the cost of operation with these components. It is now clear that energy storage coupled with accurate solar and wind forecasting make up the only combination that can succeed in dispatchable renewable energy resources. Conventional batteries scale linearly in size, so the price becomes a barrier for large systems. Flow batteries scale sub-linearly and promise to be useful if their performance can be shown to provide sufficient support for solar and wind-base electricity generation resources. Compressed air energy storage provides the most desirable answer in terms of scalability and performance in all areas except efficiency. With the support of the DOE, Tucson Electric Power and Science Foundation Arizona, the Arizona Research Institute for Solar Energy (AzRISE) at the University of Arizona has had the opportunity to investigate CAES as a potential energy storage resource.

Diesel engines and air pollution: facts and figures

International Nuclear Information System (INIS)

Chaaban, Farid

1998-01-01

Traffic densities and resulting air pollution, in any country are directly related to the degree of urbanization and the size and characteristics of the transportation sector. In Lebanon, the car ownership rate is among the highest in the world and its consequence is the drastic deterioration in ambient air quality in Greater Beirut and other organized regions. In this article, features of diesel engines are described. The environmental impacts of diesel engines, in relation of petrol engines are briefly presented. Pollutants provocated by diesel fuel, due to its contents in Carbon , Sulfur and gaseous emissions (noise level, smoke, Carbon Monoxide emissions, smell) as well as the economical aspects are given in comparison with petrol engines. Conclusion is given that diesel engines will help in reducing air pollution caused by transport sector in Lebanon, only if some required vehicles conditions are satisfied

Application of a generic superstructure-based formulation to the design of wind-pumped-storage hybrid systems on remote islands

International Nuclear Information System (INIS)

Chen, Cheng-Liang; Chen, Hui-Chu; Lee, Jui-Yuan

2016-01-01

Highlights: • A rigorous model for hybrid power system (HPS) design to support a remote island. • Use pumped hydro storage to store tentative surplus electricity. • Formulate the HPS design problem as a mixed-integer linear program (MILP). - Abstract: This paper aims to present a mathematical model for the design of a hybrid power system (HPS) to support a remote island with 100 thousand citizens. The goal is to reduce diesel fuel consumption by adequate expansion of wind power supply. Pumped hydroelectric storage (PHS) is used in the HPS to buffer the impact of intermittent behavior of wind energy. A superstructure is proposed for HPS design, considering all possible capital decisions (e.g. the number of wind turbines) and hourly-basis operational variables (such as the amount of surplus electricity in storage and its discharge). The HPS design problem can then be formulated as a mixed-integer linear program (MILP) based on the proposed superstructure. For a given total share of wind power, the optimal mix of diesel-based and wind power supplies as well as the required capacity of PHS are determined using a four-step optimization approach, involving minimizing (i) the consumption of diesel fuel, (ii) the number of wind turbines, (iii) the size of the upper water reservoir, and (iv) the charge/discharge rates of the PHS system. In this sequential optimization, the objective value obtained in a previous step is added as an additional constraint to the next step. The proposed HPS design model is applied to a real case study of the remote K Island on the other side of Taiwan Strait using hourly-basis, year-round historical data. Inclusion of other renewable energy sources, such as photovoltaic cells and biomass-fired power plants, as well as economic perspectives will be considered in future work.

Systems Performance Analyses of Alaska Wind-Diesel Projects; Kotzebue, Alaska (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

Baring-Gould, I.

2009-04-01

This fact sheet summarizes a systems performance analysis of the wind-diesel project in Kotzebue, Alaska. Data provided for this project include wind turbine output, average wind speed, average net capacity factor, and optimal net capacity factor based on Alaska Energy Authority wind data, estimated fuel savings, and wind system availability.

Challenges and solutions of implementing and supporting wind diesel applications in remote (AK) locations

Energy Technology Data Exchange (ETDEWEB)

Pingree, B. [Northern Power Systems, Barre, VT (United States)

2010-07-01

This PowerPoint presentation discussed the methods used by Northern Power Systems to install and support wind-diesel applications in remote locations in Alaska. Over 90 wind turbines have been installed in the state over the last 5 years. Drivers behind the increase in wind turbine installations include the recent energy crisis as well as the introduction of several financial incentives for renewable energy. The correct equipment is needed to overcome the technical challenges associated with wind-diesel systems in remote cold temperature areas. Multiple projects are synchronized within regions, and remote energy management software is used. Centralized power production is promoted where possible, and technicians are trained locally. The wind-diesel market has become successful in Alaska as a result of leadership, a streamline grant and permitting process, and a program that supports First Nations empowerment. Photographs of various Northern Power Systems projects in Alaska were included. tabs., figs.

Analysis of the operating behaviour of wind/Diesel systems with short term storage

International Nuclear Information System (INIS)

Beyer, H.G.; Gabler, H.; Stoecklein, A.

1993-01-01

We are examining wind/Diesel systems with batteries and wind turbines of different sizes by simulation calculations. Apart from the fuel consumption and the number of starts of the Diesel engines, we determine the energy flow via the battery. We introduce dimensions of the battery for two special types of batteries and discuss the annual battery charge/discharge cycles to be expected. (orig.) [de

Storage of compressed air. A possibility for an enhanced utilization of wind energy?; Druckluftspeicherung. Ein Weg zur verstaerkten Windenergienutzung?

Energy Technology Data Exchange (ETDEWEB)

Kretschmer, Rutger [DREWAG - Stadtwerke Dresden GmbH, Dresden (Germany). Hauptabt. Vertrieb und Beschaffung

2008-07-01

The high prices for fossil energy sources are due to increasing demand, limited production quotas and exhaustion of strategically positioned deposits. Likewise the electricity prices increase to. High electricity tariffs improve the investment climate for renewable energies independently from the fuel costs. The positive development of the renewable energy is accompanied by serious disadvantages. Thus, the conditions for grid control and for the operation of fossil power stations deteriorate. The author of the contribution under consideration reports on the storage of compressed air as a possibility for the use of wind energy.

Remote power supply by wind/diesel/battery systems - operational experience and economy

International Nuclear Information System (INIS)

Kniehl, R.; Cramer, G.; Toenges, K.H.

1995-01-01

To continuously supply remote villages and settlements not connected to the public grid with electric power is an ambitious technical task considering ecological and economical points of view. The German company SMA has developed a modular supply system as a solution for this task in the range of 30 kW to 5 MW. Meanwhile more than 20 applications of these 'Intelligent Power Systems (IPS)' have proved their technical reliability and economical competitiveness worldwide under different, and also extreme environmental conditions. Actually it is the first commercially available advanced Wind/Diesel/Battery System for remote area electrification. The modular autonomous electric supply systems realized by SMA basically consist of two or more diesel power sets, battery storage with converter, a rotating phaseshifter, and an optional number of wind turbines. All modules are coupled on the 3-phase AC system grid and run in various parallel configurations depending on the wind speed and the consumer power demand. The control system operates fully automatical and offers a very user-friendly graphical interface. This advanced system control also contains a remote control and operating data output via modem and telephone line. SMA and CES have considerable experience with Wind/Diesel/Battery Systems for more than eight years. In many cases wind energy converters in the power range of 30 to 40 kW were used, but it is also possible to use larger wind turbines (e.g. 250 kW). In the following the system technology is described in detail, experience of different system sizes in several countries of application is presented, and economical analyses for power supply by IPS are given in comparison to a conventional fully diesel power supply. (author)

Remote power supply by wind/diesel/battery systems - operational experience and economy

Energy Technology Data Exchange (ETDEWEB)

Kniehl, R [CES - Consulting and Engineering Services, Heidelberg (Germany); Cramer, G; Toenges, K H [SMA Regelsysteme GmbH, Niestetal (Germany)

1996-12-31

To continuously supply remote villages and settlements not connected to the public grid with electric power is an ambitious technical task considering ecological and economical points of view. The German company SMA has developed a modular supply system as a solution for this task in the range of 30 kW to 5 MW. Meanwhile more than 20 applications of these `Intelligent Power Systems (IPS)` have proved their technical reliability and economical competitiveness worldwide under different, and also extreme environmental conditions. Actually it is the first commercially available advanced Wind/Diesel/Battery System for remote area electrification. The modular autonomous electric supply systems realized by SMA basically consist of two or more diesel power sets, battery storage with converter, a rotating phaseshifter, and an optional number of wind turbines. All modules are coupled on the 3-phase AC system grid and run in various parallel configurations depending on the wind speed and the consumer power demand. The control system operates fully automatical and offers a very user-friendly graphical interface. This advanced system control also contains a remote control and operating data output via modem and telephone line. SMA and CES have considerable experience with Wind/Diesel/Battery Systems for more than eight years. In many cases wind energy converters in the power range of 30 to 40 kW were used, but it is also possible to use larger wind turbines (e.g. 250 kW). In the following the system technology is described in detail, experience of different system sizes in several countries of application is presented, and economical analyses for power supply by IPS are given in comparison to a conventional fully diesel power supply. (author)

Remote power supply by wind/diesel/battery systems - operational experience and economy

Energy Technology Data Exchange (ETDEWEB)

Kniehl, R. [CES - Consulting and Engineering Services, Heidelberg (Germany); Cramer, G.; Toenges, K.H. [SMA Regelsysteme GmbH, Niestetal (Germany)

1995-12-31

To continuously supply remote villages and settlements not connected to the public grid with electric power is an ambitious technical task considering ecological and economical points of view. The German company SMA has developed a modular supply system as a solution for this task in the range of 30 kW to 5 MW. Meanwhile more than 20 applications of these `Intelligent Power Systems (IPS)` have proved their technical reliability and economical competitiveness worldwide under different, and also extreme environmental conditions. Actually it is the first commercially available advanced Wind/Diesel/Battery System for remote area electrification. The modular autonomous electric supply systems realized by SMA basically consist of two or more diesel power sets, battery storage with converter, a rotating phaseshifter, and an optional number of wind turbines. All modules are coupled on the 3-phase AC system grid and run in various parallel configurations depending on the wind speed and the consumer power demand. The control system operates fully automatical and offers a very user-friendly graphical interface. This advanced system control also contains a remote control and operating data output via modem and telephone line. SMA and CES have considerable experience with Wind/Diesel/Battery Systems for more than eight years. In many cases wind energy converters in the power range of 30 to 40 kW were used, but it is also possible to use larger wind turbines (e.g. 250 kW). In the following the system technology is described in detail, experience of different system sizes in several countries of application is presented, and economical analyses for power supply by IPS are given in comparison to a conventional fully diesel power supply. (author)

Compressed Air Energy Storage in Denmark

DEFF Research Database (Denmark)

Salgi, Georges Garabeth; Lund, Henrik

2006-01-01

is analysed with regard to the Danish energy system. In Denmark, wind power supplies 20% of the electricity demand and 50% is produced by combined heat and power (CHP). The operation of CAES requires high electricity price volatility. However, in the Nordic region, large hydro capacities have so far kept......Compressed air energy storage system (CAES) is a technology which can be used for integrating more fluctuating renewable energy sources into the electricity supply system. On a utility scale, CAES has a high feasibility potential compared to other storage technologies. Here, the technology...

Consequences of Reducing the Cost of PV Modules on a PV Wind Diesel Hybrid System with Limited Sizing Components

Directory of Open Access Journals (Sweden)

Jones S. Silva

2012-01-01

Full Text Available The use of renewable resources for power supply in family homes has passed the stage of utopia to became a reality, with limits set by technical and economic parameters. This paper presents the results of a project originated from the initiative of a middle-class family to achieve energy independence at home. The starting point was the concept of home with “zero energy” in which the total energy available is equal to the energy consumed. The solution devised to meet the energy demand of the residence in question is a PV wind diesel hybrid system connected to the grid, with the possibility of energy storage in batteries and in the form of heating water and the environment of the house. As a restriction, the family requested that the system would represent little impact to the lifestyle and landscape. This paper aims to assess the consequences of reductions in the cost of the PV modules on the optimization space, as conceived by the software Homer. The results show that for this system, a 50% reduction in the cost of PV modules allows all viable solutions including PV modules.

29 CFR 1917.154 - Compressed air.

Science.gov (United States)

2010-07-01

... 29 Labor 7 2010-07-01 2010-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed a...

Study of Micro Grid Hybrid System of Photovoltaic and Diesel Engine

Directory of Open Access Journals (Sweden)

Novitasari Dwi

2016-01-01

Full Text Available Indonesia has abundant potentials of new and renewable energy that can be used for electricity generation, especially in rural areas which have no access for grid electricity yet. The energy resources can be from solar, water, biomass or biofuel. Many villagers still use diesel generators to produce electricity in their villages. It is considered expensive because fuel price in rural areas increases 2-3 times than the normal price due to transportation cost. Hybrid system using renewable energy resources is one of the solutions to produce electricity in affordable cost for rural area. The idea is to combine diesel generators and photovoltaic toproduce electricity. Moreover, the diesel engine fuel can be replaced with biofuel. This study will analyze the hybrid system in a small scale which consists of 1kWp photovoltaic and 3 kW diesel engine. Electric load power will vary. The system is controlled by a single bidirectional inverter whichconverts power from DC to AC and vice versa

IMPLEMENTATION OF DIOXANE AND DIESEL FUEL BLENDS TO REDUCE EMISSION AND TO IMPROVE PERFORMANCE OF THE COMPRESSION IGNITION ENGINE

Directory of Open Access Journals (Sweden)

SENDILVELAN S.

2017-11-01

Full Text Available Performance of a compression ignition engine fuelled with 1, 4 Dioxane- diesel blends is evaluated. A single-cylinder, air-cooled, direct injection diesel engine developing a power output of 5.2 kW at 1500 rev/min is used. Base data is generated with standard diesel fuel subsequently; five fuel blends namely 90:10, 80:20, 70:30, 60:40 and 50:50 percentages by volume of diesel and dioxane were prepared and tested in the diesel engine. Engine performance and emission data were used to optimize the blends for reducing emission and improving performance. Results show improved performance with B10 blends compared to neat fuel for all conditions of the engine. Other blends recorded marginal decrease in brake thermal efficiency. The maximum efficiency for B30, B50 blends at peak load are 26.3%, 25.2% respectively against 29.1% for sole fuel. NOx emissions were found to be high or the blends. Peak pressure and rate of pressure rise are increased with increase in dioxane ratio due to improved combustion rate. Heat release pattern shows higher premixed combustion rate with the blends. Higher ignition delay and lower combustion duration are found with all blends than neat diesel fuel.

Performance Guaranteed Inertia Emulation forDiesel-Wind System Feed Microgrid via ModelReference Control

Energy Technology Data Exchange (ETDEWEB)

Melin, Alexander M. [ORNL; Zhang, Yichen [University of Tennessee, Knoxville (UTK), Department of Electrical Engineering and Computer Science; Djouadi, Seddik [University of Tennessee, Knoxville (UTK), Department of Electrical Engineering and Computer Science; Olama, Mohammed M. [ORNL

2017-04-01

In this paper, a model reference control based inertia emulation strategy is proposed. Desired inertia can be precisely emulated through this control strategy so that guaranteed performance is ensured. A typical frequency response model with parametrical inertia is set to be the reference model. A measurement at a specific location delivers the information of disturbance acting on the diesel-wind system to the referencemodel. The objective is for the speed of the diesel-wind system to track the reference model. Since active power variation is dominantly governed by mechanical dynamics and modes, only mechanical dynamics and states, i.e., a swing-engine-governor system plus a reduced-order wind turbine generator, are involved in the feedback control design. The controller is implemented in a three-phase diesel-wind system feed microgrid. The results show exact synthetic inertia is emulated, leading to guaranteed performance and safety bounds.

Functional Group Analysis for Diesel-like Mixing-Controlled Compression Ignition Combustion Blendstocks

Energy Technology Data Exchange (ETDEWEB)

Gaspar, Daniel J.; McCormick, Robert L.; Polikarpov, Evgueni; Fioroni, Gina; George, Anthe; Albrecht, Karl O.

2016-12-30

This report addresses the suitability of hydrocarbon and oxygenate functional groups for use as a diesel-like fuel blending component in an advanced, mixing-controlled, compression ignition combustion engine. The functional groups are chosen from those that could be derived from a biomass feedstock, and represent a full range of chemistries. This first systematic analysis of functional groups will be of value to all who are pursuing new bio-blendstocks for diesel-like fuels.

Effect of compression ratio on performance, combustion and emission characteristics of a dual fuel diesel engine run on raw biogas

International Nuclear Information System (INIS)

Bora, Bhaskor J.; Saha, Ujjwal K.; Chatterjee, Soumya; Veer, Vijay

2014-01-01

Highlights: • Maximum brake thermal efficiency of 20.04% was obtained in dual fuel mode. • Compression ratio of 18 produced the maximum brake thermal efficiency. • Maximum replacement of diesel was found to be 79.46% at a compression ratio of 18. • CO gets reduced by 26.22% with the increase of compression ratio from 16 to18. • HC gets reduced by 41.97% with the increase of compression ratio from 16 to18. - Abstract: The energy consumption of the world is increasing at a staggering rate due to population explosion. The extensive use of energy has led to fossil fuel depletion and the rise in pollution. Renewable energy holds the key solution to these aforementioned problems. Biogas, one such renewable fuel, can be used in a diesel engine under dual fuel mode for the generation of power. This work attempts to unfold the effect of compression ratio on the performance, combustion and emission characteristics of a dual fuel diesel engine run on raw biogas. For this investigation, a 3.5 kW single cylinder, direct injection, water cooled, variable compression ratio diesel engine is converted into a biogas run dual fuel diesel engine by connecting a venturi gas mixer at the inlet manifold. Experiments have been conducted at various compression ratios (18, 17.5, 17 and 16) and under different loading conditions fixing the standard injection timing at 23° before top dead centre. At 100% load, the brake thermal efficiencies of the dual fuel mode are found to be 20.04%, 18.25%, 17.07% and 16.42% at compression ratios of 18, 17.5, 17 and 16, respectively, whereas at the same load, the diesel mode shows an efficiency of 27.76% at a compression ratio of 17.5. The maximum replacement of the precious fossil fuel is found to be 79.46%, 76.1%, 74% and 72% at compression ratios of 18, 17.5, 17 and 16, respectively at 100% load. For the dual fuel mode, on an average, there is a reduction in carbon monoxide as well as hydrocarbon emission by 26.22% and 41.97% when compression

Future Potential of Hybrid and Diesel Powertrains in the U.S. Light-duty Vehicle Market

Energy Technology Data Exchange (ETDEWEB)

Greene, D.L.

2004-08-23

Diesel and hybrid technologies each have the potential to increase light-duty vehicle fuel economy by a third or more without loss of performance, yet these technologies have typically been excluded from technical assessments of fuel economy potential on the grounds that hybrids are too expensive and diesels cannot meet Tier 2 emissions standards. Recently, hybrid costs have come down and the few hybrid makes available are selling well. Diesels have made great strides in reducing particulate and nitrogen oxide emissions, and are likely though not certain to meet future standards. In light of these developments, this study takes a detailed look at the market potential of these two powertrain technologies and their possible impacts on light-duty vehicle fuel economy. A nested multinomial logit model of vehicle choice was calibrated to 2002 model year sales of 930 makes, models and engine-transmission configurations. Based on an assessment of the status and outlook for the two technologies, market shares were predicted for 2008, 2012 and beyond, assuming no additional increase in fuel economy standards or other new policy initiatives. Current tax incentives for hybrids are assumed to be phased out by 2008. Given announced and likely introductions by 2008, hybrids could capture 4-7% and diesels 2-4% of the light-duty market. Based on our best guesses for further introductions, these shares could increase to 10-15% for hybrids and 4-7% for diesels by 2012. The resulting impacts on fleet average fuel economy would be about +2% in 2008 and +4% in 2012. If diesels and hybrids were widely available across vehicle classes, makes, and models, they could capture 40% or more of the light-duty vehicle market.

PV-HYBRID and MINI-GRID. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

Within the 3rd European Conference at the Centre de Congres in Aix en Provence (France) between 11th and 12th May, 2006, the following lessons were held: (1) Small electric networks: European drivers and projects for the integration of RES and DG into the electricity grids of the future (Manuel Sanchez-Jimenez); (2) PV hybrid system within mini grids - IEA PVPS programme (Meuch Konraf); (3) Renewables for the developing world (Alvaro Ponce Plaza); (4) Rural electicity supply using photovoltaic / - Diesel hybrid systems: Attractive for investors in the renewable energy sector? (Andreas Hahn); (5) Economic analysis of stand-alone and grid-connected photovoltaic systems under current tariff structure of Taiwan (Yaw-Juen Wang); (6) Using wind-PV-diesel hybrid system for electrification of remote village in Western Libya (N.M. Kreama); (7) Venezuela's renewable energy program for small towns and rural areas ''Sembrando Luz'' (Jorge Torres); (8) AeroSmart5, the professional, sysem-compatible small-scale wind energy converter will be tested in field tests (Fabian Jochem); (9) Lifetime, test procedures and recommendations for optimal operating strategies for lead-acid-batteries in renewable energy systems - A survey on results from European projects from the 5th framework programme (Rudi Kaiser); (10) Prototype of a reversible fuel cell system for autonomous power supplies (Tom Smolinska); (11) Interconnection management in microgrids (Michel Vandenbergh); (12) Control strategy for a small-scale stand-alone power system based on renewable energy and hydrogen (Harald Miland); (13) Standard renewable electricity supply for people in rural areas - mini-grids in western provinces of China (Michael Wollny); (14) The Brava island a ''100% renewable energy'' project (Jean-Christian Marcel); (15) Breakthrough to a new era of PV-hybrid systems with the help of standardised components communication? (Michael Mueller); (16) Standardized

Potential for using a tyre pyrolysis oil-biodiesel blend in a diesel engine at different compression ratios

International Nuclear Information System (INIS)

Sharma, Abhishek; Murugan, S.

2015-01-01

Highlights: • The possibility of operating a compression ignition engine with a non petroleum diesel fuel. • A possible solution to replace certain amount of biodiesel by tyre pyrolysis oil in a biodiesel fueled diesel engine. • The optimum compression ratio for engine fueled with biodiesel-tyre pyrolysis oil blend. - Abstract: This study is aimed at investigating effects of varying the compression ratio at optimum injection timing and nozzle opening pressure on the behaviour of a diesel engine, using a non-petroleum fuel, i.e. a blend of 80% biodiesel, and 20% oil obtained from pyrolysis of waste tyres. The engine was subjected to one lower (16.5) and one higher (18.5) compression ratio in addition to the standard compression ratio of 17.5. At the higher compression ratio of 18.5 and full load, shorter ignition delay, maximum cylinder pressure and higher heat release rate were found for the blend, compared to those of the original compression ratio. The increase in the compression ratio from 17.5 to 18.5 for the blend improved the brake thermal efficiency by about 8% compared to that of the original compression ratio at full load. The experimental results indicated that for the blend at a higher compression ratio of 18.5, the brake specific carbon monoxide (BSCO), brake specific hydrocarbon emission (BSHC) and smoke opacity were reduced by about 10.5%, 32%, and 17.4% respectively, than those of the original compression ratio at full load

Dynamic multi-stage dispatch of isolated wind–diesel power systems

International Nuclear Information System (INIS)

Hu, Yu; Morales, Juan M.; Pineda, Salvador; Sánchez, María Jesús; Solana, Pablo

2015-01-01

Highlights: • Optimal decision-making model for isolated hybrid wind–diesel power system is proposed. • Wind power uncertainty and conditional operating cost are considered. • Battery wear cost of the energy storage system is included in the model. • The results are compared with deterministic dispatch strategies. - Abstract: An optimal dispatch strategy is crucial for an isolated wind–diesel power system to save diesel fuel and maintain the system stability. The uncertainty associated with the stochastic character of the wind is, though, a challenging problem for this optimization. In this paper, a dynamic multi-stage decision-making model is proposed to determine the diesel power output that minimizes the cost of running and maintaining the wind–diesel power system. Optimized operational decisions for each time period are generated dynamically considering the path-dependent nature of the optimal dispatch policy, given the plausible future realizations of the wind power production. A numerical case study is analyzed and it is demonstrated that the proposed stochastic dynamic optimization model significantly outperforms the traditional deterministic dispatch strategies

Wind energy-hydrogen storage hybrid power generation

Energy Technology Data Exchange (ETDEWEB)

Wenjei Yang; Orhan Aydin [University of Michigan, Ann Arbor, MI (United States). Dept. of Mechanical Engineering and Applied Mechanics

2001-07-01

In this theoretical investigation, a hybrid power generation system utilizing wind energy and hydrogen storage is presented. Firstly, the available wind energy is determined, which is followed by evaluating the efficiency of the wind energy conversion system. A revised model of windmill is proposed from which wind power density and electric power output are determined. When the load demand is less than the output of the generation, the excess electric power is relayed to the electrolytic cell where it is used to electrolyse the de-ionized water. Hydrogen thus produced can be stored as hydrogen compressed gas or liquid. Once the hydrogen is stored in an appropriate high-pressure vessel, it can be used in a combustion engine, fuel cell, or burned in a water-cooled burner to produce a very high-quality steam for space heating, or to drive a turbine to generate electric power. It can also be combined with organic materials to produce synthetic fuels. The conclusion is that the system produces no harmful waste and depletes no resources. Note that this system also works well with a solar collector instead of a windmill. (author)

FEASIBILITY STUDY AND OPTIMIZATION OF AN HYBRID SYSTEM ...

African Journals Online (AJOL)

30 juin 2010 ... preliminary or comparative studies, both during development (design) and normal ... year for a system using only the generator diesel and is 599 kg / year for the ... Keywords: Hybrid system- Wind- Photovoltaic-Diesel- storage ...

Kaner biodiesel production through hybrid reactor and its performance testing on a CI engine at different compression ratios

Directory of Open Access Journals (Sweden)

Ashok Kumar Yadav

2017-06-01

Full Text Available The present study deals with development of a hybrid reactor for biodiesel production based on the combined hydrodynamic cavitation and mechanical stirring processes. Biodiesel were produced using Kaner Seed Oil (KSO. The experimental results show that hybrid reactor produces 95% biodiesel yield within 45 min for 0.75% of catalyst and 6:1 M ratio which is significantly higher as compared to mechanical stirring or hydrodynamic cavitation alone. Thus biodiesel production process in hybrid reactor is cheap (high yield, efficient (time saving and environmentally friendly (lower% of catalyst. Performance study on engine shows that an increase in compression ratios (from 16 to 18 improves the engine performance using biodiesel blends as compared to petroleum diesel.

Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

Science.gov (United States)

Azoumah, Y.; Yamegueu, D.; Py, X.

2012-02-01

Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original "flexy energy" concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

International Nuclear Information System (INIS)

Azoumah, Y; Yamegueu, D; Py, X

2012-01-01

Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original 'flexy energy' concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

Combustion Temperature Effect of Diesel Engine Convert to Compressed Natural Gas Engine

OpenAIRE

Semin; Abdul R. Ismail; Rosli A. Bakar

2009-01-01

Effect of combustion temperature in the engine cylinder of diesel engine convert to Compressed Natural Gas (CNG) engine was presents in this study. The objective of this study was to investigate the engine cylinder combustion temperature effect of diesel engine convert to CNG engine on variation engine speed. Problem statement: The hypothesis was that the lower performance of CNG engine was caused by the effect of lower in engine cylinder temperature. Are the CNG engine is lower cylinder temp...

Electricity generating system. [Wind/diesel/flywheel system

Energy Technology Data Exchange (ETDEWEB)

Moody, R.L.

1992-02-05

An electricity generating system is described which includes a water tank with electric heating elements connected to the water cooling system of a diesel engine which is heated by excess output of the system. Power in excess of that required by a load which is generated by a wind turbine driven generator runs up a flywheel and further excess is absorbed in the tank. A fan associated with a radiator connected to the tank may be operated to dissipate further excess power. When the load requirements exceed the output of the generators linked to the wind turbine and the flywheel the engine operates a synchronous alternator. (author).

Baseload wind energy: modeling the competition between gas turbines and compressed air energy storage for supplemental generation

International Nuclear Information System (INIS)

Greenblatt, Jeffery B.; Succar, Samir; Denkenberger, David C.; Williams, Robert H.; Socolow, Robert H.

2007-01-01

The economic viability of producing baseload wind energy was explored using a cost-optimization model to simulate two competing systems: wind energy supplemented by simple- and combined cycle natural gas turbines ('wind+gas'), and wind energy supplemented by compressed air energy storage ('wind+CAES'). Pure combined cycle natural gas turbines ('gas') were used as a proxy for conventional baseload generation. Long-distance electric transmission was integral to the analysis. Given the future uncertainty in both natural gas price and greenhouse gas (GHG) emissions price, we introduced an effective fuel price, p NGeff , being the sum of the real natural gas price and the GHG price. Under the assumption of p NGeff =$5/GJ (lower heating value), 650 W/m 2 wind resource, 750 km transmission line, and a fixed 90% capacity factor, wind+CAES was the most expensive system at cents 6.0/kWh, and did not break even with the next most expensive wind+gas system until p NGeff =$9.0/GJ. However, under real market conditions, the system with the least dispatch cost (short-run marginal cost) is dispatched first, attaining the highest capacity factor and diminishing the capacity factors of competitors, raising their total cost. We estimate that the wind+CAES system, with a greenhouse gas (GHG) emission rate that is one-fourth of that for natural gas combined cycle plants and about one-tenth of that for pulverized coal plants, has the lowest dispatch cost of the alternatives considered (lower even than for coal power plants) above a GHG emissions price of $35/tC equiv. , with good prospects for realizing a higher capacity factor and a lower total cost of energy than all the competing technologies over a wide range of effective fuel costs. This ability to compete in economic dispatch greatly boosts the market penetration potential of wind energy and suggests a substantial growth opportunity for natural gas in providing baseload power via wind+CAES, even at high natural gas prices

Optimal construction and combined wind and diesel power production in a regional power purchase

Energy Technology Data Exchange (ETDEWEB)

Lautala, P.; Antila, H.; Raekkoelaeinen, J.; Heikkilae, H. [Tampere Univ. of Technology (Finland). Automation and Control Inst.

1998-12-31

A weak electricity transmission and distribution network and a wind generator were modelled by a non-linear dynamic model. Energy purchase of a small utility was modelled as a linear mixed integer optimisation problem. The dynamic model was used to simulate the effects of distance between the wind generator and a regional power grid and the effects of changes in the production of the wind generator. The optimisation model was used to investigate the effect of the combined diesel and wind production. In this case the results show that if the distance between the generator and the network grid is more than 70 km, then voltage fluctuations exceed acceptable levels. The optimisation provides the value of the combined diesel and wind production. (orig.)

Influence of Compression Ratio on the Performance and Emission Characteristics of Annona Methyl Ester Operated DI Diesel Engine

Directory of Open Access Journals (Sweden)

Senthil Ramalingam

2014-09-01

Full Text Available This study aims to find the optimum performance and emission characteristics of single cylinder variable compression ratio (VCR engine with different blends of Annona methyl ester (AME as fuel. The performance parameters such as specific fuel consumption (SFC, brake thermal efficiency (BTE, and emission levels of HC, CO, Smoke, and NOx were compared with the diesel fuel. It is found that, at compression ratio of 17: 1 for A20 blended fuel (20% AME + 80% Diesel shows better performance and lower emission level which is very close to neat diesel fuel. The engine was operated with different values of compression ratio (15, 16, and 17 to find out best possible combination for operating engine with blends of AME. It is also found that the increase of compression ratio increases the BTE and reduces SFC and has lower emission without any engine in design modifications.

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT II, MAINTAINING THE AIR SYSTEM--DETROIT DIESEL ENGINES.

Science.gov (United States)

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE AIR SYSTEM. TOPICS ARE (1) OPERATION AND FUNCTION, (2) AIR CLEANER, (3) AIR SHUT-DOWN HOUSING, (4) EXHAUST SYSTEM, (5) BLOWER, (6) TURBOCHARGER, AND (7) TROUBLE-SHOOTING TIPS ON THE AIR SYSTEM. THE MODULE CONSISTS OF A…

Energy Conservation In Compressed Air Systems

International Nuclear Information System (INIS)

Yusuf, I.Y.; Dewu, B.B.M.

2004-01-01

Compressed air is an essential utility that accounts for a substantial part of the electricity consumption (bill) in most industrial plants. Although the general saying Air is free of charge is not true for compressed air, the utility's cost is not accorded the rightful importance due to its by most industries. The paper will show that the cost of 1 unit of energy in the form of compressed air is at least 5 times the cost electricity (energy input) required to produce it. The paper will also provide energy conservation tips in compressed air systems

Performance of compression ignition engine with indigenous castor oil bio diesel in Pakistan

International Nuclear Information System (INIS)

Chakrabarti, M.H.

2009-01-01

Castor oil available indigenously in Pakistan was converted successfully to bio diesel and blended to 10% quantity (by volume) with high speed mineral diesel (HSD) fuel. This fuel was tested in a compression-ignition engine in order to assess its environmental emissions as well as engine performance parameters. The blended fuel was found to give lower environmental emissions in most accounts except for higher CO/sub 2/ and higher NOx. In addition, three engine performance parameters were assessed; which were engine brake power, engine torque and exhaust temperature. In the first two cases, blended bio diesel fuel gave lower figures than pure mineral diesel due to lower calorific value. However, its higher flash point resulted in higher engine exhaust temperatures than pure mineral diesel. Overall, in terms of engine performance, castor oil bio diesel (from non edible oil of castor bean -growing on marginal lands of Pakistan) fared better in comparison to canola oil bio diesel (from expensive edible oil) and can be recommended for further tests at higher blend ratios. (author)

Modelling the economics of combined wind/hydro/diesel power systems

International Nuclear Information System (INIS)

Sinha, A.

1993-01-01

A model that stimulates the performance and economics of a combined wind/hydro/diesel plant with pumped storage has been developed. It is applied to a hypothetical site to demonstrate how a subset of the cheapest configuration of plant sizes may be identified, illustrating in particular the trade-off between the hydro storage capacity and the wind turbine penetration. It seems that, with the wind and water regimes employed, pumped storage is unlikely to have significant benefits, but may be beneficial in areas without natural inflow, in which case the reservoir is used as a store for excess wind output. (author)

Effect of real-time boundary wind conditions on the air flow and pollutant dispersion in an urban street canyon—Large eddy simulations

Science.gov (United States)

Zhang, Yun-Wei; Gu, Zhao-Lin; Cheng, Yan; Lee, Shun-Cheng

2011-07-01

Air flow and pollutant dispersion characteristics in an urban street canyon are studied under the real-time boundary conditions. A new scheme for realizing real-time boundary conditions in simulations is proposed, to keep the upper boundary wind conditions consistent with the measured time series of wind data. The air flow structure and its evolution under real-time boundary wind conditions are simulated by using this new scheme. The induced effect of time series of ambient wind conditions on the flow structures inside and above the street canyon is investigated. The flow shows an obvious intermittent feature in the street canyon and the flapping of the shear layer forms near the roof layer under real-time wind conditions, resulting in the expansion or compression of the air mass in the canyon. The simulations of pollutant dispersion show that the pollutants inside and above the street canyon are transported by different dispersion mechanisms, relying on the time series of air flow structures. Large scale air movements in the processes of the air mass expansion or compression in the canyon exhibit obvious effects on pollutant dispersion. The simulations of pollutant dispersion also show that the transport of pollutants from the canyon to the upper air flow is dominated by the shear layer turbulence near the roof level and the expansion or compression of the air mass in street canyon under real-time boundary wind conditions. Especially, the expansion of the air mass, which features the large scale air movement of the air mass, makes more contribution to the pollutant dispersion in this study. Comparisons of simulated results under different boundary wind conditions indicate that real-time boundary wind conditions produces better condition for pollutant dispersion than the artificially-designed steady boundary wind conditions.

30 CFR 77.412 - Compressed air systems.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air systems. 77.412 Section 77.412... for Mechanical Equipment § 77.412 Compressed air systems. (a) Compressors and compressed-air receivers... involving the pressure system of compressors, receivers, or compressed-air-powered equipment shall not be...

Tomorrow`s diesel engines: towards a new equilibrium; Moteurs diesel de demain: vers un nouvel equilibre

Energy Technology Data Exchange (ETDEWEB)

Bastenhof, D. [SEMT Pielstick, 93 - Saint Denis (France)

1997-12-31

After a review of the main principles governing combustion in diesel engines and the influence of ambient air conditions on pollutant emissions (and more especially NOx), emission level limits concerning NOx, CO, HC and ashes are presented and discussed according to their applications in the various types of diesel engines. The influence of fuel type is also examined and several ways to reduce NOx emissions in liquid fuel diesel engines are reported: mechanical modifications (compression ratio), water injection, exhaust gas recirculation, exhaust gas processing, fume and ash filtration. Cost issues are also discussed, through comparisons with gas turbines

Sensitivity analysis for the energy performance assessment of hybrid compressed air energy storage systems

International Nuclear Information System (INIS)

Briola, Stefano; Di Marco, Paolo; Gabbrielli, Roberto; Riccardi, Juri

2017-01-01

Highlights: •A sensitivity analysis and DOE of the complete hybrid CAES are carried out. •The influence of the storage site volume on performance indicators is negligible. •The performances increase with the decrease of the compressor outlet pressure. •The performances are correlated for each temperature increase in combustion chamber. •Hybridization of Huntorf implies a significant increase of its first law efficiency. -- Abstract: A detailed mathematical model was developed for the complete Hybrid Compressed Air Energy Storage (H-CAES) configuration with underground storage site and liquid thermal energy storage, operating with a sequence of processes (charging, holding and discharging with respective duration) in arbitrary order. A sensitivity analysis was carried out in order to calculate several performance indicators of the complete H-CAES configuration, in relation to the simultaneous change of several process parameters. The methodology “Design of Experiments” was applied to the results of the sensitivity analysis in order to calculate the main effects of each process parameter on each performance indicator. The influence of the storage site volume on each performance indicator is negligible. The reduction of the compressor group outlet pressure and of the turbine group power allows a more effective thermodynamic utilization both of the energy stored by the compressors and of the overall energy supplied to the plant. Furthermore, the former utilization is more effective by an increase of the gas temperature in the combustion chambers, whereas the latter utilization is worsened. Moreover, as case study, the existing diabatic CAES plant of Huntorf was modified by introducing a diathermic oil thermal storage. This plant is suitable to operate according to a partial hybrid configuration by the deactivation of the heat exchanger located upstream of the low pressure turbine. The thermodynamic utilization of the overall energy supplied to the plant

Study on Vibration of Marine Diesel-Electric Hybrid Propulsion System

OpenAIRE

Nengqi Xiao; Ruiping Zhou; Xiang Xu; Xichen Lin

2016-01-01

This study analyzes the characteristics of hybrid propulsion shafting and builds mathematical models and vibration equations of shafting using the lumped parameter method. Main focus is on the asymmetric double diesel propulsion shafting operation process and the impact of the phase angle and motor excitation on torsional vibration of shafting. Model result is validated by testing results conducted on double diesel propulsion shafting bench. Mathematical model and model-building methods of sh...

Compressed Air Production Using Vehicle Suspension

OpenAIRE

Ninad Arun Malpure; Sanket Nandlal Bhansali

2015-01-01

Abstract Generally compressed air is produced using different types of air compressors which consumes lot of electric energy and is noisy. In this paper an innovative idea is put forth for production of compressed air using movement of vehicle suspension which normal is wasted. The conversion of the force energy into the compressed air is carried out by the mechanism which consists of the vehicle suspension system hydraulic cylinder Non-return valve air compressor and air receiver. We are co...

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXI, I--MAINTAINING THE AIR SYSTEM--CATERPILLAR DIESEL ENGINE, II--UNDERSTANDING REAR END SUSPENSION.

Science.gov (United States)

Minnesota State Dept. of Education, St. Paul. Div. of Vocational and Technical Education.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF THE DIESEL ENGINE AIR SYSTEM AND REAR AXLE SUSPENSION USED ON DIESEL POWERED VEHICLES. TOPICS ARE (1) AIR INDUCTION AND EXHAUST SYSTEM, (2) VALVE MECHANISM, (3) TROUBLESHOOTING THE AIR SYSTEM, (4) PURPOSE OF VEHICLE SUSPENSION, (5) TANDEM…

Compressed Air/Vacuum Transportation Techniques

Science.gov (United States)

Guha, Shyamal

2011-03-01

General theory of compressed air/vacuum transportation will be presented. In this transportation, a vehicle (such as an automobile or a rail car) is powered either by compressed air or by air at near vacuum pressure. Four version of such transportation is feasible. In all versions, a ``c-shaped'' plastic or ceramic pipe lies buried a few inches under the ground surface. This pipe carries compressed air or air at near vacuum pressure. In type I transportation, a vehicle draws compressed air (or vacuum) from this buried pipe. Using turbine or reciprocating air cylinder, mechanical power is generated from compressed air (or from vacuum). This mechanical power transferred to the wheels of an automobile (or a rail car) drives the vehicle. In type II-IV transportation techniques, a horizontal force is generated inside the plastic (or ceramic) pipe. A set of vertical and horizontal steel bars is used to transmit this force to the automobile on the road (or to a rail car on rail track). The proposed transportation system has following merits: virtually accident free; highly energy efficient; pollution free and it will not contribute to carbon dioxide emission. Some developmental work on this transportation will be needed before it can be used by the traveling public. The entire transportation system could be computer controlled.

Effects of ethanol added fuel on exhaust emissions and combustion in a premixed charge compression ignition diesel engine

Directory of Open Access Journals (Sweden)

Kim Yungjin

2015-01-01

Full Text Available The use of diesel engines for vehicle has been increasing recently due to its higher thermal efficiency and lower CO2 emission level. However, in the case of diesel engine, NOx increases in a high temperature combustion region and particulate matter is generated in a fuel rich region. Therefore, the technique of PCCI (premixed charge compression ignition is often studied to get the peak combustion temperature down and to make a better air-fuel mixing. However it also has got a limited operating range and lower engine power produced by the wall wetting and the difficulty of the ignition timing control. In this research, the effect of injection strategies on the injected fuel behavior, combustion and emission characteristics in a PCCI engine were investigated to find out the optimal conditions for fuel injection, and then ethanol blended diesel fuel was used to control the ignition timing. As a result, the combustion pressures and ROHR (rate of heat release of the blended fuel became lower, however, IMEP showed fewer differences. Especially in the case of triple injection, smoke could be reduced a little and NOx emission decreased a lot by using the ethanol blended fuel simultaneously without much decreasing of IMEP compared to the result of 100% diesel fuel.

Potential hazards of compressed air energy storage in depleted natural gas reservoirs.

Energy Technology Data Exchange (ETDEWEB)

Cooper, Paul W.; Grubelich, Mark Charles; Bauer, Stephen J.

2011-09-01

This report is a preliminary assessment of the ignition and explosion potential in a depleted hydrocarbon reservoir from air cycling associated with compressed air energy storage (CAES) in geologic media. The study identifies issues associated with this phenomenon as well as possible mitigating measures that should be considered. Compressed air energy storage (CAES) in geologic media has been proposed to help supplement renewable energy sources (e.g., wind and solar) by providing a means to store energy when excess energy is available, and to provide an energy source during non-productive or low productivity renewable energy time periods. Presently, salt caverns represent the only proven underground storage used for CAES. Depleted natural gas reservoirs represent another potential underground storage vessel for CAES because they have demonstrated their container function and may have the requisite porosity and permeability; however reservoirs have yet to be demonstrated as a functional/operational storage media for compressed air. Specifically, air introduced into a depleted natural gas reservoir presents a situation where an ignition and explosion potential may exist. This report presents the results of an initial study identifying issues associated with this phenomena as well as possible mitigating measures that should be considered.

An Environmentally-Friendly Tourist Village in Egypt Based on a Hybrid Renewable Energy System––Part One: What Is the Optimum City?

Directory of Open Access Journals (Sweden)

Fahd Diab

2015-07-01

Full Text Available The main objective of this work is to select the optimum city from five touristic Egyptian cities (Luxor, Giza, Alexandria, Qena and Aswan to establish an environmentally-friendly tourist village. The selection of the city, according to the economic cost (cost of energy (COE, net present cost (NPC and the amount of greenhouse gases (GHG emitted, is carried out with respect to four cases, based on the effects of ambient temperature and applying GHG emission penalties. According to the simulation results, using the well-known Homer software, Alexandria is the economic city for hybrid photovoltaics (PV/wind/diesel/battery and wind/diesel/battery systems, while Aswan is the most economic city for a hybrid PV/diesel/battery system. However, for a diesel/battery system there is no significant economic difference between the cities in the study. On the other hand, according to the amount of GHG emitted from a hybrid PV/wind/diesel/battery system, Qena is the optimum city if the effects of ambient temperature are considered. However, if the GHG emission penalties are applied, Aswan will be the optimum city. Furthermore, Alexandria is the optimum city if the effects of ambient temperature are considered and the GHG emission penalties are applied. Additionally, the effects of ambient temperature and applying GHG emission penalties are studied on hybrid PV/diesel/battery, wind/diesel/battery and diesel/battery systems in this study.

Dynamic performance of self-operated three-way valve used in a hybrid air conditioner

International Nuclear Information System (INIS)

Zhang, Penglei; Zhou, Dehai; Shi, Wenxing; Li, Xianting; Wang, Baolong

2014-01-01

A hybrid air conditioner combining a thermosyphon cycle with a vapor compression refrigeration cycle has a large energy saving potential compared with a common air conditioner for spaces requiring year-round cooling. The performance of the switch between the vapor compression mode and the thermosyphon mode largely impacts the safety and reliability of hybrid air conditioners. Therefore, a self-operated three-way valve is proposed. A thermodynamic model and a kinetic model are developed in this paper to evaluate the dynamic performance of the switch valve. The effects of the spring force constant, compressor discharging volume, fit clearance and piston length on the dynamic performance of the switch valve are analyzed. In conclusion, the proposed self-operated three-way valve can realize the switch operation accurately. - Highlights: •A self-operated three-way valve is proposed for hybrid air conditioners. •The thermodynamic model and kinetic model of the self-operated three-way valve are developed. •The validity of models is verified by experiments. •Effects of four main design parameters on the operating performance of the valve are researched

Experimental investigation on performance characteristics of a diesel engine using diesel-water emulsion with oxygen enriched air

Directory of Open Access Journals (Sweden)

P. Baskar

2017-03-01

Full Text Available Diesel engines occupy a crucial position in automobile industry due to their high thermal efficiency and high power to weight ratio. However, they lag behind in controlling air polluting components coming out of the engine exhaust. Therefore, diesel consumption should be analyzed for future energy consumption and this can be primarily controlled by the petroleum fuel substitution techniques for existing diesel engines, which include biodiesel, alcohol-diesel emulsions and diesel water emulsions. Among them the diesel water emulsion is found to be most suitable fuel due to reduction in particulate matter and NOx emission, besides that it also improves the brake thermal efficiency. But the major problem associated with emulsions is the ignition delay, since this is responsible for the power and torque loss. A reduction in NOx emission was observed due to reduction in combustion chamber temperature as the water concentration increases. However the side effect of emulsified diesel is a reduction in power which can be compensated by oxygen enrichment. The present study investigates the effects of oxygen concentration on the performance characteristics of a diesel engine when the intake air is enriched to 27% of oxygen and fueled by 10% of water diesel emulsion. It was found that the brake thermal efficiency was enhanced, combustion characteristics improved and there is also a reduction in HC emissions.

Thermodynamic characteristics of a novel wind-solar-liquid air energy storage system

Science.gov (United States)

Ji, W.; Zhou, Y.; Sun, Y.; Zhang, W.; Pan, C. Z.; Wang, J. J.

2017-12-01

Due to the nature of fluctuation and intermittency, the utilization of wind and solar power will bring a huge impact to the power grid management. Therefore a novel hybrid wind-solar-liquid air energy storage (WS-LAES) system was proposed. In this system, wind and solar power are stored in the form of liquid air by cryogenic liquefaction technology and thermal energy by solar thermal collector, respectively. Owing to the high density of liquid air, the system has a large storage capacity and no geographic constraints. The WS-LAES system can store unstable wind and solar power for a stable output of electric energy and hot water. Moreover, a thermodynamic analysis was carried out to investigate the best system performance. The result shows that the increases of compressor adiabatic efficiency, turbine inlet pressure and inlet temperature all have a beneficial effect.

Isothermal Kinetics of Catalyzed Air Oxidation of Diesel Soot

Directory of Open Access Journals (Sweden)

R. Prasad

2011-01-01

Full Text Available To comply with the stringent emission regulations on soot, diesel vehicles manufacturers more and more commonly use diesel particulate filters (DPF. These systems need to be regenerated periodically by burning soot that has been accumulated during the loading of the DPF. Design of the DPF requires rate of soot oxidation. This paper describes the kinetics of catalytic oxidation of diesel soot with air under isothermal conditions. Kinetics data were collected in a specially designed mini-semi-batch reactor. Under the high air flow rate assuming pseudo first order reaction the activation energy of soot oxidation was found to be, Ea = 160 kJ/ mol. ©2010 BCREC UNDIP. All rights reserved(Received: 14th June 2010, Revised: 18th July 2010, Accepted: 9th August 2010[How to Cite: R. Prasad, V.R. Bella. (2010. Isothermal Kinetics of Catalyzed Air Oxidation of Diesel Soot. Bulletin of Chemical Reaction Engineering and Catalysis, 5(2: 95-101. doi:10.9767/bcrec.5.2.796.95-101][DOI:http://dx.doi.org/10.9767/bcrec.5.2.796.95-101 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/796]Cited by in: ACS 1 |

Economic Modeling of Compressed Air Energy Storage

Directory of Open Access Journals (Sweden)

Rui Bo

2013-04-01

Full Text Available Due to the variable nature of wind resources, the increasing penetration level of wind power will have a significant impact on the operation and planning of the electric power system. Energy storage systems are considered an effective way to compensate for the variability of wind generation. This paper presents a detailed production cost simulation model to evaluate the economic value of compressed air energy storage (CAES in systems with large-scale wind power generation. The co-optimization of energy and ancillary services markets is implemented in order to analyze the impacts of CAES, not only on energy supply, but also on system operating reserves. Both hourly and 5-minute simulations are considered to capture the economic performance of CAES in the day-ahead (DA and real-time (RT markets. The generalized network flow formulation is used to model the characteristics of CAES in detail. The proposed model is applied on a modified IEEE 24-bus reliability test system. The numerical example shows that besides the economic benefits gained through energy arbitrage in the DA market, CAES can also generate significant profits by providing reserves, compensating for wind forecast errors and intra-hour fluctuation, and participating in the RT market.

Economics of compressed air energy storage employing thermal energy storage

Energy Technology Data Exchange (ETDEWEB)

Schulte, S.C.; Reilly, R.W.

1979-11-01

The approach taken in this study is to adopt system design and capital cost estimates from three independent CAES studies (eight total designs) and, by supplying a common set of fuel/energy costs and economic assumptions in conjunction with a common methodology, to arrive at a series of levelized energy costs over the system's lifetime. In addition, some analyses are provided to gauge the sensitivity of these levelized energy costs to fuel and compression energy costs and to system capacity factors. The systems chosen for comparison are of four generic types: conventional CAES, hybrid CAES, adiabatic CAES, and an advanced-design gas turbine (GT). In conventional CAES systems the heat of compression generated during the storage operation is rejected to the environment, and later, during the energy-generation phase, turbine fuel must be burned to reheat the compressed air. In the hybrid systems some of the heat of compression is stored and reapplied later during the generation phase, thereby reducing turbine fuel requirements. The adiabatic systems store adequate thermal energy to eliminate the need for turbine fuel entirely. The gas turbine is included within the report for comparison purposes; it is an advanced-design turbine, one that is expected to be available by 1985.

Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

OpenAIRE

Hanafi H.; Hasan M.M; Rahman M.M; Noor M.M; Kadirgama K.; Ramasamy D.

2016-01-01

This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend). A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI) engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5) and 10% ethanol (E10) (in vo...

Rectal perforation by compressed air.

Science.gov (United States)

Park, Young Jin

2017-07-01

As the use of compressed air in industrial work has increased, so has the risk of associated pneumatic injury from its improper use. However, damage of large intestine caused by compressed air is uncommon. Herein a case of pneumatic rupture of the rectum is described. The patient was admitted to the Emergency Room complaining of abdominal pain and distension. His colleague triggered a compressed air nozzle over his buttock. On arrival, vital signs were stable but physical examination revealed peritoneal irritation and marked distension of the abdomen. Computed tomography showed a large volume of air in the peritoneal cavity and subcutaneous emphysema at the perineum. A rectal perforation was found at laparotomy and the Hartmann procedure was performed.

PV–wind hybrid power option for a low wind topography

International Nuclear Information System (INIS)

Bhattacharjee, Subhadeep; Acharya, Shantanu

2015-01-01

Highlights: • Optimally harness the wind energy by unification of solar resource. • Analysis of PV–wind hybrid system with tangible experience. • Cost of generation and renewable fraction are $0.488/kWh and 0.90 respectively. • Maximum wind penetration is observed to be 32.75% with installed PV–wind system. • Indicative annual grid electricity conservation is 90%. - Abstract: Solar and wind are clean energy sources with enormous potential to alleviate grid dependence. The paper aims to optimally harness the wind resource with the support of solar energy through hybrid technology for a north-east Indian state Tripura (low wind topography). Techno-economic analysis of a photovoltaic (PV)-wind hybrid simulation model has been performed for small scale application in an educational building. The study also evaluates the tangible performance of a similar plant in practical condition of the site. It has emerged from the study that major energy generation is turning out from PV segment which is promising almost all round the year. Nonetheless, a considerable amount of wind power is found to be generated during half of the year when average PV power production is comparatively less. The cost of electricity from the simulation model is found to be $0.488/kWh while renewable fraction in the total electricity share is obtained to be 0.90. From the actual performance of the plant, maximum wind penetration is observed to be 32.75%

A study on the amount of pilot injection and its effects on rich and lean boundaries of the premixed CNG/air mixture for a CNG/diesel dual-fuel engine

Energy Technology Data Exchange (ETDEWEB)

Zhiqiang Lin; Wanhua Su [Tianjin University (China). State Key Laboratory of Engines

2003-07-01

A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must be made richer, otherwise THC emissions would increase. However, the soot emissions remain almost unchanged at a very low level. (author)

A Novel Pumped Hydro Combined with Compressed Air Energy Storage System

Directory of Open Access Journals (Sweden)

Erren Yao

2013-03-01

Full Text Available A novel pumped hydro combined with compressed air energy storage (PHCA system is proposed in this paper to resolve the problems of bulk energy storage in the wind power generation industry over an area in China, which is characterised by drought and water shortages. Thermodynamic analysis of the energy storage system, which focuses on the pre-set pressure, storage volume capacity, water air volume ratio, pump performance, and water turbine performance of the storage system, is also presented. This paper discovers how such parameters affect the performance of the whole system. The ideal performance of this novel system has the following advantages: a simple, highly effective and low cost structure, which is comparable to the efficiency of a traditional pumped hydro storage system. Research results show a great solution to the current storage constraints encountered in the development of the wind power industry in China, which have been widely recognised as a bottleneck in the wind energy storage industry.

Compressed Air Production Using Vehicle Suspension

Directory of Open Access Journals (Sweden)

Ninad Arun Malpure

2015-08-01

Full Text Available Abstract Generally compressed air is produced using different types of air compressors which consumes lot of electric energy and is noisy. In this paper an innovative idea is put forth for production of compressed air using movement of vehicle suspension which normal is wasted. The conversion of the force energy into the compressed air is carried out by the mechanism which consists of the vehicle suspension system hydraulic cylinder Non-return valve air compressor and air receiver. We are collecting air in the cylinder and store this energy into the tank by simply driving the vehicle. This method is non-conventional as no fuel input is required and is least polluting.

Small wind power plants : results of the Nordic wind diesel projects for large telecommunications companies; Implantation d'une centrale eolienne comme source d'energie d'appoint pour des stations de telecommunications

Energy Technology Data Exchange (ETDEWEB)

Ilinca, A.; Chaumel, J.L. [ATI Eolien, Rimouski, PQ (Canada); Thibault, G. [Entreprises MB, PQ (Canada)

2005-07-01

Two wind-diesel generating stations have been installed at telecommunication towers in the remote communities of Kuujjuarapik and Lac Julien in northern Quebec. The use of wind power contributes to the sustainable development in these remote areas by lowering the reliance on costly helicopter-transported diesel fuel and by reducing the release of greenhouse gases to the atmosphere. The technical characteristics of the Bergey 100 kW turbine with battery charger were presented along with the technical characteristics of the EolDie control panel that controls the supply of electricity from either the wind or diesel power generators. For the first time, the ATI-Wind technology system that was installed can supply the needs of the large telecommunication towers of Bell Canada and Telebec from either the wind or the diesel generators. The system is also capable of shutting down the diesel generators when wind energy is sufficient to take over. Early results from June 2005 showed that the diesel generators could be turned off for 55 per cent of the time. Preliminary results of these 2 projects were discussed by the firms in charge of the diesel and wind aspects and recommendations for improvements to the control systems were presented. 11 figs.

Greenhouse gas emissions from heavy-duty natural gas, hybrid, and conventional diesel on-road trucks during freight transport

Science.gov (United States)

Quiros, David C.; Smith, Jeremy; Thiruvengadam, Arvind; Huai, Tao; Hu, Shaohua

2017-11-01

Heavy-duty on-road vehicles account for 70% of all freight transport and 20% of transportation-sector greenhouse gas (GHG) emissions in the United States. This study measured three prevalent GHG emissions - carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) - from seven heavy-duty vehicles, fueled by diesel and compressed natural gas (CNG), and compliant to the MY 2007 or 2010 U.S. EPA emission standards, while operated over six routes used for freight movement in California. Total combined (tractor, trailer, and payload) weights were 68,000 ± 1000 lbs. for the seven vehicles. Using the International Panel on Climate Change (IPCC) radiative forcing values for a 100-year time horizon, N2O emissions accounted for 2.6-8.3% of total tailpipe CO2 equivalent emissions (CO2-eq) for diesel vehicles equipped with Diesel Oxidation Catalyst, Diesel Particulate Filter, and Selective Catalytic Reduction system (DOC + DPF + SCR), and CH4 emissions accounted for 1.4-5.9% of CO2-eq emissions from the CNG-powered vehicle with a three-way catalyst (TWC). N2O emissions from diesel vehicles equipped with SCR (0.17-0.30 g/mi) were an order of magnitude higher than diesel vehicles without SCR (0.013-0.023 g/mi) during highway operation. For the vehicles selected in this test program, we measured 11-22% lower CO2-eq emissions from a hybrid compared to conventional diesel vehicles during transport over lower-speed routes of the freight transport system, but 20-27% higher CO2-eq emissions during higher-speed routes. Similarly, a CNG vehicle emitted up to 15% lower CO2-eq compared to conventional diesel vehicles over more neutral-grade highway routes, but emitted up to 12% greater CO2-eq emissions over routes with higher engine loads.

Optimal Photovoltaic System Sizing of a Hybrid Diesel/PV System

Directory of Open Access Journals (Sweden)

Ahmed Belhamadia

2017-03-01

Full Text Available This paper presents a cost analysis study of a hybrid diesel and Photovoltaic (PV system in Kuala Terengganu, Malaysia. It first presents the climate conditions of the city followed by the load profile of a 2MVA network; the system was evaluated as a standalone system. Diesel generator rating was considered such that it follows ISO 8528. The maximum size of the PV system was selected such that its penetration would not exceed 25%. Several sizes were considered but the 400kWp system was found to be the most cost efficient. Cost estimation was done using Hybrid Optimization Model for Electric Renewable (HOMER. Based on the simulation results, the climate conditions and the NEC 960, the numbers of the maximum and minimum series modules were suggested as well as the maximum number of the parallel strings.

Evaluation of thermal energy storage materials for advanced compressed air energy storage systems

Energy Technology Data Exchange (ETDEWEB)

Zaloudek, F.R.; Wheeler, K.R.; Marksberry, L.

1983-03-01

Advanced Compressed-Air Energy Storage (ACAS) plants have the near-term potential to reduce the fuel consumption of compressed-air plants from 33 to 100%, depending upon their design. Fuel is saved by storing some or all of the heat of compression as sensible heat which is subsequently used to reheat the compressed air prior to expansion in the turbine generator. The thermal storage media required for this application must be low cost and durable. The objective of this project was to screen thermal store materials based on their thermal cycle durability, particulate formation and corrosion resistant characteristics. The materials investigated were iron oxide pellets, Denstone pebbles, cast-iron balls, and Dresser basalt rock. The study specifically addressed the problems of particle formation and thermal ratcheting of the materials during thermal cycling and the chemical attack on the materials by the high temperature and moist environment in an ACAS heat storage bed. The results indicate that from the durability standpoint Denstone, cast iron containing 27% or more chromium, and crushed Dresser basalt would possibly stand up to ACAS conditions. If costs are considered in addition to durability and performance, the crushed Dresser basalt would probably be the most desirable heat storage material for adiabatic and hybrid ACAS plants, and more in-depth longer term thermal cycling and materials testing of Dresser basalt is recommended. Also recommended is the redesign and costing analysis of both the hybrid and adiabatic ACAS facilities based upon the use of Dresser basalt as the thermal store material.

The Technical and Economic Study of Solar-Wind Hybrid Energy System in Coastal Area of Chittagong, Bangladesh

Directory of Open Access Journals (Sweden)

Shuvankar Podder

2015-01-01

Full Text Available The size optimization and economic evaluation of the solar-wind hybrid renewable energy system (RES to meet the electricity demand of 276 kWh/day with 40 kW peak load have been determined in this study. The load data has been collected from the motels situated in the coastal areas of Patenga, Chittagong. RES in standalone as well as grid connected mode have been considered. The optimal system configurations have been determined based on systems net present cost (NPC and cost of per unit energy (COE. A standalone solar-wind-battery hybrid system is feasible and economically comparable to the present cost of diesel based power plant if 8% annual capacity shortage is allowed. Grid tied solar-wind hybrid system, where more than 70% electricity contribution is from RES, is economically comparable to present grid electricity price. Moreover, grid tied RES results in more than 60% reduction in greenhouse gases emission compared to the conventional grid. Sensitivity analysis has been performed in this study to determine the effect of capital cost variation or renewable resources variation on the system economy. Simulation result of sensitivity analysis has showed that 20% reduction of installation cost results in nearly 9%–12% reductions in cost of per unit energy.

Optimal scheduling for distributed hybrid system with pumped hydro storage

International Nuclear Information System (INIS)

Kusakana, Kanzumba

2016-01-01

Highlights: • Pumped hydro storage is proposed for isolated hybrid PV–Wind–Diesel systems. • Optimal control is developed to dispatch power flow economically. • A case study is conducted using the model for an isolated load. • Effects of seasons on the system’s optimal scheduling are examined through simulation. - Abstract: Photovoltaic and wind power generations are currently seen as sustainable options of in rural electrification, particularly in standalone applications. However the variable character of solar and wind resources as well as the variable load demand prevent these generation systems from being totally reliable without suitable energy storage system. Several research works have been conducted on the use of photovoltaic and wind systems in rural electrification; however most of these works have not considered other ways of storing energy except for conventional battery storage systems. In this paper, an energy dispatch model that satisfies the load demand, taking into account the intermittent nature of the solar and wind energy sources and variations in demand, is presented for a hybrid system consisting of a photovoltaic unit, a wind unit, a pumped hydro storage system and a diesel generator. The main purpose of the developed model is to minimize the hybrid system’s operation cost while optimizing the system’s power flow considering the different component’s operational constraints. The simulations have been performed using “fmincon” implemented in Matlab. The model have been applied to two test examples; the simulation results are analyzed and compared to the case where the diesel generator is used alone to supply the given load demand. The results show that using the developed control model for the proposed hybrid system, fuel saving can be achieved compared to the case where the diesel is used alone to supply the same load patters.

30 CFR 57.13020 - Use of compressed air.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Use of compressed air. 57.13020 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Compressed Air and Boilers § 57.13020 Use of compressed air. At no time shall compressed air be directed toward a...

30 CFR 56.13020 - Use of compressed air.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Use of compressed air. 56.13020 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Compressed Air and Boilers § 56.13020 Use of compressed air. At no time shall compressed air be directed toward a person...

Lifecycle cost assessment and carbon dioxide emissions of diesel, natural gas, hybrid electric, fuel cell hybrid and electric transit buses

International Nuclear Information System (INIS)

Lajunen, Antti; Lipman, Timothy

2016-01-01

This paper evaluates the lifecycle costs and carbon dioxide emissions of different types of city buses. The simulation models of the different powertrains were developed in the Autonomie vehicle simulation software. The carbon dioxide emissions were calculated both for the bus operation and for the fuel and energy pathways from well to tank. Two different operating environment case scenarios were used for the primary energy sources, which were Finland and California (USA). The fuel and energy pathways were selected appropriately in relation to the operating environment. The lifecycle costs take into account the purchase, operating, maintenance, and possible carbon emission costs. Based on the simulation results, the energy efficiency of city buses can be significantly improved by the alternative powertrain technologies. Hybrid buses have moderately lower carbon dioxide emissions during the service life than diesel buses whereas fully-electric buses have potential to significantly reduce carbon dioxide emissions, by up to 75%. The lifecycle cost analysis indicates that diesel hybrid buses are already competitive with diesel and natural gas buses. The high costs of fuel cell and battery systems are the major challenges for the fuel cell hybrid buses in order to reduce lifecycle costs to more competitive levels. - Highlights: • Alternative powertrains can significantly improve energy efficiency of transit buses. • Operating environment has an important impact on the lifecycle costs of buses. • Diesel hybrid buses are already cost effective solution for public transportation. • The cost of fuel cell technology is the major challenge for fuel cell hybrid buses. • Fully-electric buses have potential to significantly reduce carbon dioxide emissions.

Solar-Diesel Hybrid Power System Optimization and Experimental Validation

Science.gov (United States)

Jacobus, Headley Stewart

As of 2008 1.46 billion people, or 22 percent of the World's population, were without electricity. Many of these people live in remote areas where decentralized generation is the only method of electrification. Most mini-grids are powered by diesel generators, but new hybrid power systems are becoming a reliable method to incorporate renewable energy while also reducing total system cost. This thesis quantifies the measurable Operational Costs for an experimental hybrid power system in Sierra Leone. Two software programs, Hybrid2 and HOMER, are used during the system design and subsequent analysis. Experimental data from the installed system is used to validate the two programs and to quantify the savings created by each component within the hybrid system. This thesis bridges the gap between design optimization studies that frequently lack subsequent validation and experimental hybrid system performance studies.

Pemanfaatan Energi Gas Buang Motor Diesel Stasioner untuk Pemanas Air

OpenAIRE

Rahardjo Tirtoatmodjo

1999-01-01

Exhaust gas from a diesel engine is having a big deal of energy. In a stationer diesel engine, the enthalpy of water will be increased by flowing the water in a spiral pipe which is located in the exhaust manifold of the engine. Using copper pipes in this heat exchanger, it's efficiency is found up to 69,5 %. Abstract in Bahasa Indonesia : Gas buang dari motor diesel masih memiliki sejumlah energi panas yang cukup tinggi. Pada motor diesel stasioner, dengan mengalirkan air pada pipa spiral ya...

Claw-pole Synchronous Generator for Compressed Air Energy Storage

Directory of Open Access Journals (Sweden)

PAVEL Valentina

2013-05-01

Full Text Available This paper presents a claw-poles generator for compressed air energy storage systems. It is presented the structure of such a system used for compensating of the intermittency of a small wind energy system. For equipping of this system it is chosen the permanent magnet claw pole synchronous generator obtained by using ring NdFeB permanentmagnets instead of excitation coil. In such a way the complexity of the scheme is reduced and the generator become maintenance free. The new magnetic flux density in the air-gap is calculated by magneticreluctance method and by FEM method and the results are compared with measured values in the old and new generator.

46 CFR 112.50-7 - Compressed air starting.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Compressed air starting. 112.50-7 Section 112.50-7... air starting. A compressed air starting system must meet the following: (a) The starting, charging... air compressors addressed in paragraph (c)(3)(i) of this section. (b) The compressed air starting...

A hybrid data compression approach for online backup service

Science.gov (United States)

Wang, Hua; Zhou, Ke; Qin, MingKang

2009-08-01

With the popularity of Saas (Software as a service), backup service has becoming a hot topic of storage application. Due to the numerous backup users, how to reduce the massive data load is a key problem for system designer. Data compression provides a good solution. Traditional data compression application used to adopt a single method, which has limitations in some respects. For example data stream compression can only realize intra-file compression, de-duplication is used to eliminate inter-file redundant data, compression efficiency cannot meet the need of backup service software. This paper proposes a novel hybrid compression approach, which includes two levels: global compression and block compression. The former can eliminate redundant inter-file copies across different users, the latter adopts data stream compression technology to realize intra-file de-duplication. Several compressing algorithms were adopted to measure the compression ratio and CPU time. Adaptability using different algorithm in certain situation is also analyzed. The performance analysis shows that great improvement is made through the hybrid compression policy.

Semi-volatile and particulate emissions from the combustion of alternative diesel fuels.

Science.gov (United States)

Sidhu, S; Graham, J; Striebich, R

2001-01-01

Motor vehicle emissions are a major anthropogenic source of air pollution and contribute to the deterioration of urban air quality. In this paper, we report results of a laboratory investigation of particle formation from four different alternative diesel fuels, namely, compressed natural gas (CNG), dimethyl ether (DME), biodiesel, and diesel, under fuel-rich conditions in the temperature range of 800-1200 degrees C at pressures of approximately 24 atm. A single pulse shock tube was used to simulate compression ignition (CI) combustion conditions. Gaseous fuels (CNG and DME) were exposed premixed in air while liquid fuels (diesel and biodiesel) were injected using a high-pressure liquid injector. The results of surface analysis using a scanning electron microscope showed that the particles formed from combustion of all four of the above-mentioned fuels had a mean diameter less than 0.1 microm. From results of gravimetric analysis and fuel injection size it was found that under the test conditions described above the relative particulate yields from CNG, DME, biodiesel, and diesel were 0.30%. 0.026%, 0.52%, and 0.51%, respectively. Chemical analysis of particles showed that DME combustion particles had the highest soluble organic fraction (SOF) at 71%, followed by biodiesel (66%), CNG (38%) and diesel (20%). This illustrates that in case of both gaseous and liquid fuels, oxygenated fuels have a higher SOF than non-oxygenated fuels.

Effect of Variable Compression Ratio on Performance of a Diesel Engine Fueled with Karanja Biodiesel and its Blends

Science.gov (United States)

Mishra, Rahul Kumar; soota, Tarun, Dr.; singh, Ranjeet

2017-08-01

Rapid exploration and lavish consumption of underground petroleum resources have led to the scarcity of underground fossil fuels moreover the toxic emissions from such fuels are pernicious which have increased the health hazards around the world. So the aim was to find an alternative fuel which would meet the requirements of petroleum or fossil fuels. Biodiesel is a clean, renewable and bio-degradable fuel having several advantages, one of the most important of which is being its eco-friendly and better knocking characteristics than diesel fuel. In this work the performance of Karanja oil was analyzed on a four stroke, single cylinder, water cooled, variable compression ratio diesel engine. The fuel used was 5% - 25% karanja oil methyl ester by volume in diesel. The results such obtained are compared with standard diesel fuel. Several properties i.e. Brake Thermal Efficiency, Brake Specific Fuel Consumptions, Exhaust Gas Temperature are determined at all operating conditions & at variable compression ratio 17 and 17.5.

Performance evaluation of stand alone hybrid PV-wind generator

Energy Technology Data Exchange (ETDEWEB)

Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H. [Faculty of Electrical Engineering, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia); Yahaya, M. S. [Faculty of Engineering Technology, Universiti Teknikal Malaysia Melaka (UTeM), Hang Tuah Jaya, 76100 Melaka (Malaysia)

2015-05-15

This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

Performance evaluation of stand alone hybrid PV-wind generator

Science.gov (United States)

Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H.; Yahaya, M. S.

2015-05-01

This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand.

Performance evaluation of stand alone hybrid PV-wind generator

International Nuclear Information System (INIS)

Nasir, M. N. M.; Saharuddin, N. Z.; Sulaima, M. F.; Jali, Mohd Hafiz; Bukhari, W. M.; Bohari, Z. H.; Yahaya, M. S.

2015-01-01

This paper presents the performance evaluation of standalone hybrid system on Photovoltaic (PV)-Wind generator at Faculty of Electrical Engineering (FKE), UTeM. The hybrid PV-Wind in UTeM system is combining wind turbine system with the solar system and the energy capacity of this hybrid system can generate up to charge the battery and supply the LED street lighting load. The purpose of this project is to evaluate the performance of PV-Wind hybrid generator. Solar radiation meter has been used to measure the solar radiation and anemometer has been used to measure the wind speed. The effectiveness of the PV-Wind system is based on the various data that has been collected and compared between them. The result shows that hybrid system has greater reliability. Based on the solar result, the correlation coefficient shows strong relationship between the two variables of radiation and current. The reading output current followed by fluctuate of solar radiation. However, the correlation coefficient is shows moderate relationship between the two variables of wind speed and voltage. Hence, the wind turbine system in FKE show does not operate consistently to produce energy source for this hybrid system compare to PV system. When the wind system does not fully operate due to inconsistent energy source, the other system which is PV will operate and supply the load for equilibrate the extra load demand

Replacing diesel by solar in the Amazon: short-term economic feasibility of PV-diesel hybrid systems

International Nuclear Information System (INIS)

Schmid, A.L.; Hoffmann, C.A.A.

2004-01-01

Energy planning in the Brazilian Amazon faces two major challenges. One is that of helping the off-grid population improve a situation of discomfort, environmental risks and high lighting costs. Another is that of cutting fuel subsidies in the local utility grids supplied by diesel generators. Simulation shows that PV systems with energy storage connected to existing diesel generators, allowing them to be turned of during the day, provide the lowest energy costs. Implementation potential of that choice is evaluated for local grids up to 100 kW, where transportation costs cause maximal wholesale diesel prices for Northern Brazil to be increased of 15% and more, it is economical to convert diesel systems up to 50 kW peak power into hybrid systems. In locations where the costs increase is of 45% and more, systems up to 100 kW turn economical. A new legal mechanism for subrogation of diesel subsidies to renewable energy projects changes those limits to 0% and 21%, respectively. Therefore, the actors in power generation are motivated to consider solar energy. A program with the scope described should give the Brazilian photovoltaic industry a relevant push and launch a transition towards a sustainable power supply for the region

Study of a solar PV-diesel-battery hybrid power system for a remotely located population near Rafha, Saudi Arabia

International Nuclear Information System (INIS)

Rehman, Shafiqur; Al-Hadhrami, Luai M.

2010-01-01

This study presents a PV-diesel hybrid power system with battery backup for a village being fed with diesel generated electricity to displace part of the diesel by solar. The hourly solar radiation data measured at the site along with PV modules mounted on fixed foundations, four generators of different rated powers, diesel prices of 0.2-1.2US$/l, different sizes of batteries and converters were used to find an optimal power system for the village. It was found that a PV array of 2000 kW and four generators of 1250, 750, 2250 and 250 kW; operating at a load factor of 70% required to run for 3317 h/yr, 4242 h/yr, 2820 h/yr and 3150 h/yr, respectively; to produce a mix of 17,640 MWh of electricity annually and 48.33 MWh per day. The cost of energy (COE) of diesel only and PV/diesel/battery power system with 21% solar penetration was found to be 0.190$/kWh and 0.219$/kWh respectively for a diesel price of 0.2$/l. The sensitivity analysis showed that at a diesel price of 0.6$/l the COE from hybrid system become almost the same as that of the diesel only system and above it, the hybrid system become more economical than the diesel only system. (author)

Performance and exhaust emission characteristics of variable compression ratio diesel engine fuelled with esters of crude rice bran oil.

Science.gov (United States)

Vasudeva, Mohit; Sharma, Sumeet; Mohapatra, S K; Kundu, Krishnendu

2016-01-01

As a substitute to petroleum-derived diesel, biodiesel has high potential as a renewable and environment friendly energy source. For petroleum importing countries the choice of feedstock for biodiesel production within the geographical region is a major influential factor. Crude rice bran oil is found to be good and viable feedstock for biodiesel production. A two step esterification is carried out for higher free fatty acid crude rice bran oil. Blends of 10, 20 and 40 % by vol. crude rice bran biodiesel are tested in a variable compression ratio diesel engine at compression ratio 15, 16, 17 and 18. Engine performance and exhaust emission parameters are examined. Cylinder pressure-crank angle variation is also plotted. The increase in compression ratio from 15 to 18 resulted in 18.6 % decrease in brake specific fuel consumption and 14.66 % increase in brake thermal efficiency on an average. Cylinder pressure increases by 15 % when compression ratio is increased. Carbon monoxide emission decreased by 22.27 %, hydrocarbon decreased by 38.4 %, carbon dioxide increased by 17.43 % and oxides of nitrogen as NOx emission increased by 22.76 % on an average when compression ratio is increased from 15 to 18. The blends of crude rice bran biodiesel show better results than diesel with increase in compression ratio.

Combustion and exhaust emission characteristics of a compression ignition engine using liquefied petroleum gas-Diesel blended fuel

International Nuclear Information System (INIS)

Qi, D.H.; Bian, Y.ZH.; Ma, ZH.Y.; Zhang, CH.H.; Liu, SH.Q.

2007-01-01

Towards the effort of reducing pollutant emissions, especially smoke and nitrogen oxides, from direct injection (DI) Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. The use of liquefied petroleum gas (LPG) as an alternative fuel is a promising solution. The potential benefits of using LPG in Diesel engines are both economical and environmental. The high auto-ignition temperature of LPG is a serious advantage since the compression ratio of conventional Diesel engines can be maintained. The present contribution describes an experimental investigation conducted on a single cylinder DI Diesel engine, which has been properly modified to operate under LPG-Diesel blended fuel conditions, using LPG-Diesel blended fuels with various blended rates (0%, 10%, 20%, 30%, 40%). Comparative results are given for various engine speeds and loads for conventional Diesel and blended fuels, revealing the effect of blended fuel combustion on engine performance and exhaust emissions

Compressed air energy storage with waste heat export: An Alberta case study

International Nuclear Information System (INIS)

Safaei, Hossein; Keith, David W.

2014-01-01

Highlights: • Export of compression waste heat from CAES facilities for municipal heating can be profitable. • D-CAES concept has a negative abatement cost of −$40/tCO 2 e under the studied circumstances. • Economic viability of D-CAES highly depends on distance between air storage site and heat load. - Abstract: Interest in compressed air energy storage (CAES) technology has been renewed driven by the need to manage variability form rapidly growing wind and solar capacity. Distributed CAES (D-CAES) design aims to improve the efficiency of conventional CAES through locating the compressor near concentrated heating loads so capturing additional revenue through sales of compression waste heat. A pipeline transports compressed air to the storage facility and expander, co-located at some distance from the compressor. The economics of CAES are strongly dependant on electricity and gas markets in which they are embedded. As a case study, we evaluated the economics of two hypothetical merchant CAES and D-CAES facilities performing energy arbitrage in Alberta, Canada using market data from 2002 to 2011. The annual profit of the D-CAES plant was $1.3 million more on average at a distance of 50 km between the heat load and air storage sites. Superior economic and environmental performance of D-CAES led to a negative abatement cost of −$40/tCO 2 e. We performed a suite of sensitivity analyses to evaluate the impact of size of heat load, size of air storage, ratio of expander to compressor size, and length of pipeline on the economic feasibility of D-CAES

Investigations of effects of pilot injection with change in level of compression ratio in a common rail diesel engine

Directory of Open Access Journals (Sweden)

Gajarlawar Nilesh

2013-01-01

Full Text Available These day diesel engines are gaining lots of attention as prime movers for various source of transportation. It offers better drive ability, very good low end torque and importantly the lower CO2 emission. Diesel engines are bridging the gap between gasoline and diesel engines. Better noise vibration and harshness levels of gasoline engine are realized to great extent in diesel engine, thanks to common rail direct injection system. Common rail injection system is now well known entity. Its unique advantage is flexible in operation. In common rail injection system, number of injection prior and after main injection at different injection pressure is possible. Due to multiple injections, gain in emission reduction as well as noise has been already experienced and demonstrated by researcher in the past. However, stringent emission norms for diesel engine equipped vehicle demands for further lower emission of oxides of nitrogen (NOx and particulate matter (PM. In the present paper, authors attempted to study the effect of multiple injections in combination with two level of compression ratio. The aim was to study the combustion behavior with the reduced compression ratio which is going to be tried out as low temperature combustion concept in near future. The results were compared with the current level of compression ratio. Experiments were carried out in 2.2L cubic capacity engine with two levels of compression ratios. Pilot injection separation and quantities were varied keeping the main injection, rail pressure, boost pressure and EGR rate constant. Cylinder pressure traces and gross heat release rates were measured and analyzed to understand the combustion behavior.

Optimization of combustion chamber geometry and operating conditions for compression ignition engine fueled with pre-blended gasoline-diesel fuel

International Nuclear Information System (INIS)

Lee, Seokhwon; Jeon, Joonho; Park, Sungwook

2016-01-01

Highlights: • Pre-blended gasoline-diesel fuel was used with direct injection system. • KIVA-CHEMKIN code modeled dual-fuel fuel spray and combustion processes with discrete multi-component model. • The characteristics of Combustion and emission on pre-blended fuel was investigated with various fuel reactivities. • Optimization of combustion chamber shape improved combustion performance of the gasoline-diesel blended fuel engine. - Abstract: In this study, experiments and numerical simulations were used to improve the fuel efficiency of compression ignition engine using a gasoline-diesel blended fuel and an optimization technology. The blended fuel is directly injected into the cylinder with various blending ratios. Combustion and emission characteristics were investigated to explore the effects of gasoline ratio on fuel blend. The present study showed that the advantages of gasoline-diesel blended fuel, high thermal efficiency and low emission, were maximized using the numerical optimization method. The ignition delay and maximum pressure rise rate increased with the proportion of gasoline. As the gasoline fraction increased, the combustion duration and the indicated mean effective pressure decreased. The homogeneity of the fuel-air mixture was improved due to longer ignition delay. Soot emission was significantly reduced up to 90% compared to that of conventional diesel. The nitrogen oxides emissions of the blended fuel increased slightly when the start of injection was retarded toward top dead center. For the numerical study, KIVA-CHEMKIN multi-dimensional CFD code was used to model the combustion and emission characteristics of gasoline-diesel blended fuel. The micro genetic algorithm coupled with the KIVA-CHEMKIN code were used to optimize the combustion chamber shape and operating conditions to improve the combustion performance of the blended fuel engine. The optimized chamber geometry enhanced the fuel efficiency, for a level of nitrogen oxides

Wind Generator & Biomass No-draft Gasification Hybrid

Science.gov (United States)

Hein, Matthew R.

or an anticipated 1,766 tonnes of biomass. The levelized cost of electricity (COE) ranged from 65.6/GJ (236/MWh) to 208.9/GJ (752/MWh) with the price of generated electricity being most sensitive to the biomass feedstock cost and the levelized COE being significantly impacted by the high cost of compressed storage. The resulting electrical energy available to the grid has an approximate wholesale value of 13.5/GJ (48.6/MWh) based on year 2007 Midwest Reliability Organization (MRO) regional averages [1]. Therefore, the annual average wholesale value of the generated electricity is lower than the cost to produce the electricity. A significant deficiency of this simple comparison is that it does not consider the fact that the proposed wind and biomass gasification hybrid is now a dispatchable source of electricity with a near net-zero lifetime carbon footprint and storage capability. Dispatchable power can profit from market fluctuations that dramatically increase the value of available electricity so that in addition to providing base power the hybrid facility can store energy during low price points in the market and generate at full capacity during points of high prices. Any financial incentive for energy generated from reduced carbon technologies will also increase the value of electricity produced. Also, alternative operational parameters that do not require the costly storage of synthetic natural gas (SNG) will likely result in a more competitive levelized COE. Additional benefits of the system are in the flexibility of transporting wind and biomass energy produced as well as the end use of the energy. Instead of high-voltage electrical transmission a gas line can now be used to transport energy produced by the wind. Syngas can also be further processed into higher energy density liquefied syngas. Liquid fuels can then be transported via commercial freight on existing road infrastructure.

Environmental assessment: Kotzebue Wind Installation Project, Kotzebue, Alaska

International Nuclear Information System (INIS)

1998-05-01

The DOE is proposing to provide financial assistance to the Kotzebue Electric Association to expand its existing wind installation near Kotzebue, Alaska. Like many rural Alaska towns, Kotzebue uses diesel-powered generators to produce its electricity, the high cost of which is currently subsidized by the Alaska State government. In an effort to provide a cost effective and clean source of electricity, reduce dependence on diesel fuel, and reduce air pollutants, the DOE is proposing to fund an experimental wind installation to test commercially available wind turbines under Arctic conditions. The results would provide valuable information to other Alaska communities experiencing similar dependence on diesel-powered generators. The environmental assessment for the proposed wind installation assessed impacts to biological resources, land use, electromagnetic interference, coastal zone, air quality, cultural resources, and noise. It was determined that the project does not constitute a major Federal action significantly affecting the quality of the human environment. Therefore, the preparation of an environmental impact statement is not required, and DOE has issued a Finding of No Significant Impact

Environmental assessment: Kotzebue Wind Installation Project, Kotzebue, Alaska

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-05-01

The DOE is proposing to provide financial assistance to the Kotzebue Electric Association to expand its existing wind installation near Kotzebue, Alaska. Like many rural Alaska towns, Kotzebue uses diesel-powered generators to produce its electricity, the high cost of which is currently subsidized by the Alaska State government. In an effort to provide a cost effective and clean source of electricity, reduce dependence on diesel fuel, and reduce air pollutants, the DOE is proposing to fund an experimental wind installation to test commercially available wind turbines under Arctic conditions. The results would provide valuable information to other Alaska communities experiencing similar dependence on diesel-powered generators. The environmental assessment for the proposed wind installation assessed impacts to biological resources, land use, electromagnetic interference, coastal zone, air quality, cultural resources, and noise. It was determined that the project does not constitute a major Federal action significantly affecting the quality of the human environment. Therefore, the preparation of an environmental impact statement is not required, and DOE has issued a Finding of No Significant Impact.

A Hybrid Wind-Farm Parametrization for Mesoscale and Climate Models

Science.gov (United States)

Pan, Yang; Archer, Cristina L.

2018-04-01

To better understand the potential impact of wind farms on weather and climate at the regional to global scales, a new hybrid wind-farm parametrization is proposed for mesoscale and climate models. The proposed parametrization is a hybrid model because it is not based on physical processes or conservation laws, but on the multiple linear regression of the results of large-eddy simulations (LES) with the geometric properties of the wind-farm layout (e.g., the blockage ratio and blockage distance). The innovative aspect is that each wind turbine is treated individually based on its position in the farm and on the wind direction by predicting the velocity upstream of each turbine. The turbine-induced forces and added turbulence kinetic energy (TKE) are first derived analytically and then implemented in the Weather Research and Forecasting model. Idealized simulations of the offshore Lillgrund wind farm are conducted. The wind-speed deficit and TKE predicted with the hybrid model are in excellent agreement with those from the LES results, while the wind-power production estimated with the hybrid model is within 10% of that observed. Three additional wind farms with larger inter-turbine spacing than at Lillgrund are also considered, and a similar agreement with LES results is found, proving that the hybrid parametrization works well with any wind farm regardless of the spacing between turbines. These results indicate the wind-turbine position, wind direction, and added TKE are essential in accounting for the wind-farm effects on the surroundings, for which the hybrid wind-farm parametrization is a promising tool.

Energy management system for stand-alone diesel-wind-biomass microgrid with energy storage system

International Nuclear Information System (INIS)

Wang, Chengshan; Liu, Yixin; Li, Xialin; Guo, Li; Qiao, Lei; Lu, Hai

2016-01-01

An energy management system for stand-alone microgrid composed of diesel generators, wind turbine generator, biomass generator and an ESS (energy storage system) is proposed in this paper. Different operation objectives are achieved by a hierarchical control structure with different time scales. Firstly, the optimal schedules of the diesel generators, wind turbine generator, biomass generator and ESS are determined fifteen minutes ahead according to the super short-term forecast of load and wind speed in the optimal scheduling layer. Comprehensive analysis which takes the uncertainty of load and wind speed into account is conducted in this layer to minimize the operation cost of the system and ensure a desirable range of the state of charge of the ESS. Secondly, the operation points of each unit are regulated dynamically to guarantee real-time power balance and safety range of diesel generation in the real-time control layer, based on which the response capability when suffering significant forecast deviation and other emergency issues, e.g. sudden load-up can be improved. Finally, the effectiveness of the proposed energy management strategy is verified on an RT-Lab based real-time simulation platform, and the economic performances with different types of ESS are analyzed as well. - Highlights: • A hierarchical control strategy is proposed for a stand-alone microgrid. • The uncertainties of load and wind speed have been considered. • Better economic performance and high reliability of the system can be achieved. • The influences of different energy storage systems have been analyzed.

Wind turbine aerodynamics

Energy Technology Data Exchange (ETDEWEB)

Johnson, D.A. [Waterloo Univ., ON (Canada). Dept. of Mechanical Engineering, Wind Energy Group

2010-07-01

The need for clean, renewable electricity in remote communities of Canada and the world was discussed in this presentation. The University of Waterloo Wind Energy Laboratory (WEL) performs research in a large scale indoor environment on wind turbines, blade aerodynamics, and aeroacoustics. A key area of research involves developing turbines for remote off-grid communities where climatic conditions are challenging. This presentation outlined research that is underway on wind energy and off-grid renewable energy systems. Many communities in Canada and remote communities in the rest of the world are not connected to the grid and are dependent on other means to supply electrical energy to their community. Remote communities in northern Canada have no road access and diesel is the dominant source of electrical energy for these communities. All of the community supply of diesel comes from brief winter road access or by air. The presentation discussed existing diesel systems and the solution of developing local renewable energy sources such as wind, hydro, biomass, geothermal, and solar power. Research goals, wind energy activities, experimental equipment, and the results were also presented. Research projects have been developed in wind energy; hydrogen generation/storage/utilization; power electronics/microgrid; and community engagement. figs.

Economical and environmental assessments of compressed natural gas for diesel vehicle in Thailand

Directory of Open Access Journals (Sweden)

Prateep Chouykerd

2008-08-01

Full Text Available The economic assessments for the use of compressed natural gas as fuel for several types of diesel vehicles, rarely pick up, non-fixed route truck and private truck, were studied. It is noted that two main technologies of diesel natural gas vehicle (NGV, i.e. dedicated retrofit and diesel dual fuel (DDF, were considered in this work. It was found that the dedicated retrofit needs higher investment costs than dual fuel, but can achieve higher diesel saving than dual fuel. In detail, the payback period of dual fuel non-fixed route truck was found to be identical to dual fuel private truck both in the cases of6 wheel and 10 wheel, while dedicated retrofit non-fixed route truck and private truck are also identical and have longerpay back period than dual fuel due to its higher conversion costs.This work also presents the emissions released from all types of engines especially green house gas CO2. It was found that, in the case of light duty diesel i.e. pickup truck, dedicated retrofit emitted high level of CO2 than both dual fuel and conventional diesel engines. For heavy duty i.e. non-fixed route truck and private truck vehicles, dedicated retrofit emitted a lower level of CO2 than normal diesel engine. Other pollutants from engine emission, i.e. hydrocarbon (HC,nitric oxide (NOx, carbon monoxide (CO and particulate matter, (PM were also observed. The results indicated that, inthe case of light duty diesel, dedicated retrofit engine emits higher levels of HC and CO than diesel engine; in contrast, it emits lower level of NOx and PM than diesel and dual fuel. Dual fuel emits HC and CO higher than diesel and dedicated retrofit but emits lower level of NOx and PM than diesel. Lastly, for heavy duty diesel, it was demonstrated that non-fixed route truck and private truck heavy duty dedicated retrofit have potential to reduce emissions of HC, NOx, CO and PM when compared to normal heavy duty diesel. Engine efficiencies under dual fuel and dedicated

Reducing Diesel Engine Emission Using Reactivity Controlled Approach

Directory of Open Access Journals (Sweden)

Osama Hasib Ghazal

2018-01-01

Full Text Available Several automobile manufacturers are interested in investigating of dual fuel internal combustion engines, due to high efficiencand low emissions. Many alternative fuels have been used in dual fuel mode for IC engine, such as methane, hydrogen, and natural gas. In the present study, a reactivity controlled compression ignition (RCCI engine using gasoline/diesel (G/D dual fuel has been investigated. The effectof mixing gasoline with diesel fuel on combustion characteristic, engine performance and emissions has been studied. The gasoline was injected in the engine intake port, to produce a homogeneous mixture with air. The diesel fuel was injected directly to the combustion chamber during compression stroke to initiate the combustion process. A direct injection compression ignition engine has been built and simulated using ANSYS Forte professional code. The gasoline amount in the simulation varied from (50%-80% by volume. The diesel fuel was injected to the cylinder in two stages. The model has been validated and calibrated for neat diesel fuel using available data from the literature. The results show that the heat release rate and the cylinder pressure increased when the amount of added gasoline is between 50%-60% volume of the total injected fuels, compared to the neat diesel fuel. Further addition of gasoline will have a contrary effect. In addition, the combustion duration is extended drastically when the gasoline ratio is higher than 60% which results in an incomplete combustion. The NO emission decreased drastically as the gasoline ratio increased. Moreover, addition of gasoline to the mixture increased the engine power, thermal efficienc and combustion efficienc compared to neat diesel fuel.

Three-dimensional density and compressible magnetic structure in solar wind turbulence

Science.gov (United States)

Roberts, Owen W.; Narita, Yasuhito; Escoubet, C.-Philippe

2018-03-01

The three-dimensional structure of both compressible and incompressible components of turbulence is investigated at proton characteristic scales in the solar wind. Measurements of the three-dimensional structure are typically difficult, since the majority of measurements are performed by a single spacecraft. However, the Cluster mission consisting of four spacecraft in a tetrahedral formation allows for a fully three-dimensional investigation of turbulence. Incompressible turbulence is investigated by using the three vector components of the magnetic field. Meanwhile compressible turbulence is investigated by considering the magnitude of the magnetic field as a proxy for the compressible fluctuations and electron density data deduced from spacecraft potential. Application of the multi-point signal resonator technique to intervals of fast and slow wind shows that both compressible and incompressible turbulence are anisotropic with respect to the mean magnetic field direction P⟂ ≫ P∥ and are sensitive to the value of the plasma beta (β; ratio of thermal to magnetic pressure) and the wind type. Moreover, the incompressible fluctuations of the fast and slow solar wind are revealed to be different with enhancements along the background magnetic field direction present in the fast wind intervals. The differences in the fast and slow wind and the implications for the presence of different wave modes in the plasma are discussed.

PV-hybrid and mini-grid

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Within the 5th European PV-hybrid and mini-grid conference 29th and 30th April, 2010 in Tarragona (Spain) the following lectures were held: (1) Overview of IEA PVPS Task 11 PV-hybrid systems within mini grids; (2) Photovoltaic revolution for deployment in developing countries; (3) Legal and financial conditions for the sustainable operation of mini-grids; (4) EU instruments to promote renewable energies in developing countries; (5) PV hybridization of diesel electricity generators: Conditions of profitability and examples in differential power and storage size ranges; (6) Education suit of designing PV hybrid systems; (7) Sustainable renewable energy projects for intelligent rural electrification in Laos, Cambodia and Vietnam; (8) Techno-economic feasibility of energy supply of remote villages in Palestine by PV systems, diesel generators and electric grid (Case studies: Emnazeil and Atouf villages); (9) Technical, economical and sustainability considerations of a solar PV mini grid as a tool for rural electrification in Uganda; (10) Can we rate inverters for rural electrification on the basis of energy efficiency?; (11) Test procedures for MPPT charge controllers characterization; (12) Energy storage for mini-grid stabilization; (13) Redox flow batteries - Already an alternative storage solution for hybrid PV mini-grids?; (14) Control methods for PV hybrid mini-grids; (15) Partial AC-coupling in mini-grids; (15) Normative issues of small wind turbines in PV hybrid systems; (16) Communication solutions for PV hybrid systems; (17) Towards flexible control and communication of mini-grids; (18) PV/methanol fuel cell hybrid system for powering a highway security variable message board; (19) Polygeneration smartgrids: A solution for the supply of electricity, potable water and hydrogen as fuel for transportation in remote Areas; (20) Implementation of the Bronsbergen micro grid using FACDS; (21) A revisited approach for the design of PV wind hybrid systems; (22

Dynamic programming for reduction of fuel consumption in a photovoltaic/wind/diesel generating system; Doteki keikakuho ni yoru taiyoko/furyoku/diesel hatsuden system no nenryo shohiryo no sakugen

Energy Technology Data Exchange (ETDEWEB)

Ishikawa, K.; Kenmoku, Y.; Sakakibara, T. [Toyohashi University of Technology, Aichi (Japan); Nakagawa, S. [Maizuru National College of Technology, Kyoto (Japan); Kawamoto, T. [Shizuoka University, Shizuoka (Japan)

1997-11-25

Dynamic programming is employed in the study of the operation of the diesel engine in a photovoltaic/wind-force/diesel-engine power generating system, which aims at reduction in the system fuel consumption and at determining an optimum system constitution. The parameters set in this system are the photovoltaic/wind-force supply rate, photovoltaic/wind-force power generation ratio, and battery capacity. An island in Ise Bay, with an annual load power of approximately 1.59-million kWh and mean daily load power of approximately 4336kWh is assumed as the location for the system. Observation data of Ommaezaki Weather Station are utilized for the calculation of the amount of photovoltaic/wind-force power generation. It is found as the result that the fuel consumption of the diesel engine in this system decreases to 82-84% when the natural energy supply rate is 20%. It is also found that the fuel consumption of the system records the minimum at a photovoltaic/wind-force ratio of 60/40, irrespective of the battery capacity or natural energy supply rate, and this ratio is the optimum ratio. 3 refs., 9 figs., 1 tab.

Lossless medical image compression with a hybrid coder

Science.gov (United States)

Way, Jing-Dar; Cheng, Po-Yuen

1998-10-01

The volume of medical image data is expected to increase dramatically in the next decade due to the large use of radiological image for medical diagnosis. The economics of distributing the medical image dictate that data compression is essential. While there is lossy image compression, the medical image must be recorded and transmitted lossless before it reaches the users to avoid wrong diagnosis due to the image data lost. Therefore, a low complexity, high performance lossless compression schematic that can approach the theoretic bound and operate in near real-time is needed. In this paper, we propose a hybrid image coder to compress the digitized medical image without any data loss. The hybrid coder is constituted of two key components: an embedded wavelet coder and a lossless run-length coder. In this system, the medical image is compressed with the lossy wavelet coder first, and the residual image between the original and the compressed ones is further compressed with the run-length coder. Several optimization schemes have been used in these coders to increase the coding performance. It is shown that the proposed algorithm is with higher compression ratio than run-length entropy coders such as arithmetic, Huffman and Lempel-Ziv coders.

EFFECT OF COMPRESSION RATIO ON ENERGY AND EMISSION OF VCR DIESEL ENGINE FUELLED WITH DUAL BLENDS OF BIODIESEL

Directory of Open Access Journals (Sweden)

R. D. EKNATH

2014-10-01

Full Text Available In recent 10 years biodiesel fuel was studied extensively as an alternative fuel. Most of researchers reported performance and emission of biodiesel and their blends with constant compression ratio. Also all the research was conducted with use of single biodiesel and its blend. Few reports are observed with the use of variable compression ratio and blends of more than one biodiesel. Main aim of the present study is to analyse the effect of compression ratio on the performance and emission of dual blends of biodiesel. In the present study Blends of Jatropha and Karanja with Diesel fuel was tested on single cylinder VCR DI diesel engine for compression ratio 16 and 18. High density of biodiesel fuel causes longer delay period for Jatropha fuel was observed compare with Karanja fuel. However blending of two biodiesel K20J40D results in to low mean gas temperature which is the main reason for low NOx emission.

The Influence of Diesel Fuel Subsidies and Taxes on the Potential for Solar-Powered Hybrid Systems in Africa

Directory of Open Access Journals (Sweden)

Paul Bertheau

2015-08-01

Full Text Available Many people in African countries lack access to sufficient electricity supply due to missing infrastructure of the centralized conventional power generation system. In order to provide electricity to a wider part of the population, it is necessary to exploit the vast renewable resources in African countries. Therefore, this paper scrutinizes the economic advantages of photovoltaic-based hybrid systems over fossil fuel-based power generation. A simulation model is applied in order to calculate the cost advantage of hybrid systems compared to diesel-only systems for the entire continent on a long term basis by applying two scenarios: one based on world market diesel prices and the other one based on national diesel prices. The results indicate that average power generation costs per country can be reduced by up to 0.11 €/kWh considering world market diesel prices and by up to 0.48 €/kWh considering national diesel prices. Furthermore, the effect of diesel fuel subsidies and taxes on the renewable energy potential and the respective savings are examined. These findings may ameliorate the policy development according to fossil fuel subsidies and taxes and demonstrate the advantages of decentralized renewable hybrid systems especially in rural areas of Africa.

Analysis of off-grid hybrid wind turbine/solar PV water pumping systems

Science.gov (United States)

While many remote water pumping systems exist (e.g. mechanical windmills, solar photovoltaic , wind-electric, diesel powered), very few combine both the wind and solar energy resources to possibly improve the reliability and the performance of the system. In this paper, off-grid wind turbine (WT) a...

A hybrid air conditioner driven by a hybrid solar collector

Science.gov (United States)

Al-Alili, Ali

The objective of this thesis is to search for an efficient way of utilizing solar energy in air conditioning applications. The current solar Air Conditioners (A/C)s suffer from low Coefficient of Performance (COP) and performance degradation in hot and humid climates. By investigating the possible ways of utilizing solar energy in air conditioning applications, the bottlenecks in these approaches were identified. That resulted in proposing a novel system whose subsystem synergy led to a COP higher than unity. The proposed system was found to maintain indoor comfort at a higher COP compared to the most common solar A/Cs, especially under very hot and humid climate conditions. The novelty of the proposed A/C is to use a concentrating photovoltaic/thermal collector, which outputs thermal and electrical energy simultaneously, to drive a hybrid A/C. The performance of the hybrid A/C, which consists of a desiccant wheel, an enthalpy wheel, and a vapor compression cycle (VCC), was investigated experimentally. This work also explored the use of a new type of desiccant material, which can be regenerated with a low temperature heat source. The experimental results showed that the hybrid A/C is more effective than the standalone VCC in maintaining the indoor conditions within the comfort zone. Using the experimental data, the COP of the hybrid A/C driven by a hybrid solar collector was found to be at least double that of the current solar A/Cs. The innovative integration of its subsystems allows each subsystem to do what it can do best. That leads to lower energy consumption which helps reduce the peak electrical loads on electric utilities and reduces the consumer operating cost since less energy is purchased during the on peak periods and less solar collector area is needed. In order for the proposed A/C to become a real alternative to conventional systems, its performance and total cost were optimized using the experimentally validated model. The results showed that for an

A simple, robust and reliable wind diesel concept for remote power supply

DEFF Research Database (Denmark)

Lundsager, P.; Bindner, H.

1994-01-01

The paper introduces a Wind Diesel concept suitable for remote communities, the 'Simple, Robust and Reliable Concept' developed at Riso. All components are standard components, the system is self regulating using the component controllers and there is no power electronics. The paper documents...

Survived ileocecal blowout from compressed air.

Science.gov (United States)

Weber, Marco; Kolbus, Frank; Dressler, Jan; Lessig, Rüdiger

2011-03-01

Industrial accidents with compressed air entering the gastro-intestinal tract often run fatally. The pressures usually over-exceed those used by medical applications such as colonoscopy and lead to vast injuries of the intestines with high mortality. The case described in this report is of a 26-year-old man who was harmed by compressed air that entered through the anus. He survived because of fast emergency operation. This case underlines necessity of explicit instruction considering hazards handling compressed air devices to maintain safety at work. Further, our observations support the hypothesis that the mucosa is the most elastic layer of the intestine wall.

Analysis of the potential for wind energy production in northwestern Ontario

Energy Technology Data Exchange (ETDEWEB)

Brown, C K; Warne, D F

1975-11-01

A study of the feasibility of generating electric power from wind generators at remote sites in Northwestern Ontario has been carried out on behalf of the Ontario Ministry of Energy, with project management from Ontario Hydro. The work included (1) a survey of commercially available wind driven electric plant, both currently available and planned for production, (2) an analysis of existing wind data and preparation of an isovent map for Ontario showing annual mean wind speeds, (3) the selection of suitable sites for a demonstration unit and a prototype system, (4) the matching of available plant to the wind regimes to predict annual energy production, and (5) a systems analysis of pure diesel, hybrid wind/diesel and pure wind electric plants to determine the cost of power from the various alternatives.

Rupture of esophagus by compressed air.

Science.gov (United States)

Wu, Jie; Tan, Yuyong; Huo, Jirong

2016-11-01

Currently, beverages containing compressed air such as cola and champagne are widely used in our daily life. Improper ways to unscrew the bottle, usually by teeth, could lead to an injury, even a rupture of the esophagus. This letter to editor describes a case of esophageal rupture caused by compressed air.

Effect of turbulence intensity on PM emission of heavy duty diesel trucks - Wind tunnel studies

Science.gov (United States)

Littera, D.; Cozzolini, A.; Besch, M.; Carder, D.; Gautam, M.

2017-08-01

Stringent emission regulations have forced drastic technological improvements in diesel aftertreatment systems, particularly in reducing Particulate Matter (PM) emissions. The formation and evolution of PM from modern engines are more sensitive to overall changes in the dilution process, such as rapidity of mixing, background PM present in the air. These technological advancements were made in controlled laboratory environments compliant with measurement standards (i.e. Code of Federal Regulation CFR in the USA) and are not fully representative of real-world emissions from these engines or vehicles. In light of this, a specifically designed and built wind tunnel by West Virginia University (WVU) is used for the study of the exhaust plume of a heavy-duty diesel vehicle, providing a better insight in the dilution process and the representative nanoparticles emissions in a real-world scenario. The subsonic environmental wind tunnel is capable of accommodating a full-sized heavy-duty truck and generating wind speeds in excess of 50mph. A three-dimensional gantry system allows spanning the test section and sample regions in the plume with accuracy of less than 5 mm. The gantry system is equipped with engine exhaust gas analyzers and PM sizing instruments. The investigation involves three different heavy-duty Class-8 diesel vehicles representative of three emission regulation standards, namely a US-EPA 2007 compliant, a US-EPA 2010 compliant, and a baseline vehicle without any aftertreatment technologies as a pre US-EPA 2007, respectively. The testing procedure includes three different vehicle speeds: idling, 20mph, and 35mph. The vehicles were tested on WVU's medium-duty chassis dynamometer, with the load applied to the truck reflecting the road load equation at the corresponding vehicle test speeds. Wind tunnel wind speed and vehicle speed were maintained in close proximity to one another during the entire test. Results show that the cross-sectional plume area

A review on recent size optimization methodologies for standalone solar and wind hybrid renewable energy system

International Nuclear Information System (INIS)

Al-falahi, Monaaf D.A.; Jayasinghe, S.D.G.; Enshaei, H.

2017-01-01

Highlights: • Possible combinations and configurations for standalone PV-WT HES were discussed. • Most recently used assessment parameters for standalone PV-WT HES were explained. • Optimization algorithms and software tools were comprehensively reviewed. • The recent trend of using hybrid algorithms over single algorithms was discussed. • Optimization algorithms for sizing standalone PV-WT HES were critically compared. - Abstract: Electricity demand in remote and island areas are generally supplied by diesel or other fossil fuel based generation systems. Nevertheless, due to the increasing cost and harmful emissions of fossil fuels there is a growing trend to use standalone hybrid renewable energy systems (HRESs). Due to the complementary characteristics, matured technologies and availability in most areas, hybrid systems with solar and wind energy have become the popular choice in such applications. However, the intermittency and high net present cost are the challenges associated with solar and wind energy systems. In this context, optimal sizing is a key factor to attain a reliable supply at a low cost through these standalone systems. Therefore, there has been a growing interest to develop algorithms for size optimization in standalone HRESs. The optimal sizing methodologies reported so far can be broadly categorized as classical algorithms, modern techniques and software tools. Modern techniques, based on single artificial intelligence (AI) algorithms, are becoming more popular than classical algorithms owing to their capabilities in solving complex optimization problems. Moreover, in recent years, there has been a clear trend to use hybrid algorithms over single algorithms mainly due to their ability to provide more promising optimization results. This paper aims to present a comprehensive review on recent developments in size optimization methodologies, as well as a critical comparison of single algorithms, hybrid algorithms, and software tools

Energy Cascade Rate in Compressible Fast and Slow Solar Wind Turbulence

Energy Technology Data Exchange (ETDEWEB)

Hadid, L. Z.; Sahraoui, F.; Galtier, S., E-mail: lina.hadid@lpp.polytechnique.fr [LPP, CNRS, Ecole Polytechnique, UPMC Univ Paris 06, Univ. Paris-Sud, Observatoire de Paris, Université Paris-Saclay, Sorbonne Universités, PSL Research University, F-91128 Palaiseau (France)

2017-03-20

Estimation of the energy cascade rate in the inertial range of solar wind turbulence has been done so far mostly within incompressible magnetohydrodynamics (MHD) theory. Here, we go beyond that approximation to include plasma compressibility using a reduced form of a recently derived exact law for compressible, isothermal MHD turbulence. Using in situ data from the THEMIS / ARTEMIS spacecraft in the fast and slow solar wind, we investigate in detail the role of the compressible fluctuations in modifying the energy cascade rate with respect to the prediction of the incompressible MHD model. In particular, we found that the energy cascade rate (1) is amplified particularly in the slow solar wind; (2) exhibits weaker fluctuations in spatial scales, which leads to a broader inertial range than the previous reported ones; (3) has a power-law scaling with the turbulent Mach number; (4) has a lower level of spatial anisotropy. Other features of solar wind turbulence are discussed along with their comparison with previous studies that used incompressible or heuristic (nonexact) compressible MHD models.

Energy Cascade Rate in Compressible Fast and Slow Solar Wind Turbulence

International Nuclear Information System (INIS)

Hadid, L. Z.; Sahraoui, F.; Galtier, S.

2017-01-01

Estimation of the energy cascade rate in the inertial range of solar wind turbulence has been done so far mostly within incompressible magnetohydrodynamics (MHD) theory. Here, we go beyond that approximation to include plasma compressibility using a reduced form of a recently derived exact law for compressible, isothermal MHD turbulence. Using in situ data from the THEMIS / ARTEMIS spacecraft in the fast and slow solar wind, we investigate in detail the role of the compressible fluctuations in modifying the energy cascade rate with respect to the prediction of the incompressible MHD model. In particular, we found that the energy cascade rate (1) is amplified particularly in the slow solar wind; (2) exhibits weaker fluctuations in spatial scales, which leads to a broader inertial range than the previous reported ones; (3) has a power-law scaling with the turbulent Mach number; (4) has a lower level of spatial anisotropy. Other features of solar wind turbulence are discussed along with their comparison with previous studies that used incompressible or heuristic (nonexact) compressible MHD models.

Wind Solar Hybrid System Rectifier Stage Topology Simulation

OpenAIRE

Anup M. Gakare; Subhash Kamdi

2014-01-01

This paper presents power-control strategies of a grid-connected hybrid generation system with versatile power transfer. The hybrid system allows maximum utilization of freely available renewable sources like wind and photovoltaic energies. This paper presents a new system configuration of the multi input rectifier stage for a hybrid wind and photovoltaic energy system. This configuration allows the two sources to supply the load simultaneously depending on the availability of...

A comparative life cycle assessment of diesel and compressed natural gas powered refuse collection vehicles in a Canadian city

International Nuclear Information System (INIS)

Rose, Lars; Hussain, Mohammed; Ahmed, Syed; Malek, Kourosh; Costanzo, Robert; Kjeang, Erik

2013-01-01

Consumers and organizations worldwide are searching for low-carbon alternatives to conventional gasoline and diesel vehicles to reduce greenhouse gas (GHG) emissions and their impact on the environment. A comprehensive technique used to estimate overall cost and environmental impact of vehicles is known as life cycle assessment (LCA). In this article, a comparative LCA of diesel and compressed natural gas (CNG) powered heavy duty refuse collection vehicles (RCVs) is conducted. The analysis utilizes real-time operational data obtained from the City of Surrey in British Columbia, Canada. The impact of the two alternative vehicles is assessed from various points in their life. No net gain in energy use is found when a diesel powered RCV is replaced by a CNG powered RCV. However, significant reductions (approximately 24% CO 2 -equivalent) in GHG and criteria air contaminant (CAC) emissions are obtained. Moreover, fuel cost estimations based on 2011 price levels and a 5-year lifetime for both RCVs reveal that considerable cost savings may be achieved by switching to CNG vehicles. Thus, CNG RCVs are not only favorable in terms of reduced climate change impact but also cost effective compared to conventional diesel RCVs, and provide a viable and realistic near-term strategy for cities and municipalities to reduce GHG emissions. - Highlights: ► Life cycle analysis is performed on two alternative refuse collection vehicle technologies. ► Real-time operational data obtained by the City of Surrey in British Columbia are utilized. ► The life cycle energy use is similar for diesel and CNG RCVs. ► A 24% reduction of GHG emissions (CO 2 -equivalent) may be realized by switching from diesel to CNG. ► CNG RCVs are estimated to be cost effective and may lead to reduced fuel costs.

Feasibility study for a standalone solar-wind-based hybrid energy system for application in Ethiopia

International Nuclear Information System (INIS)

Bekele, Getachew; Palm, Bjoern

2010-01-01

The aim of this paper is to investigate the possibility of supplying electricity from a solar-wind hybrid system to a remotely located model community detached from the main electricity grid in Ethiopia. The wind energy potential of four typical locations has been assessed in a previous article. The solar potential has also been investigated and the results are presented in detail in an accompanying article awaiting publication. For one of the sites, Addis Ababa, the results of the investigation are given here in detail. For the other sites, the results are given as sensitivity diagrams only. Based on the findings of the studies into energy potential, a feasibility study has been carried out on how to supply electricity to a model community of 200 families, which comprises 1000 people in total. The community is equipped with a community school and a health post. The electric load consists of both primary and deferrable types and comprises lighting, water pumps, radio receivers, and some clinical equipment. A software tool, Hybrid Optimization Model for Electric Renewables (HOMER) is used for the analysis. The result of the analysis is a list of feasible power supply systems, sorted according to their net present cost. Furthermore, sensitivity diagrams, showing the influence of wind speeds, PV costs, and diesel prices on the optimum solutions are also provided. (author)

Feasibility study for a standalone solar-wind-based hybrid energy system for application in Ethiopia

Energy Technology Data Exchange (ETDEWEB)

Bekele, Getachew; Palm, Bjoern [Department of Energy Technology, KTH, Stockholm (Sweden)

2010-02-15

The aim of this paper is to investigate the possibility of supplying electricity from a solar-wind hybrid system to a remotely located model community detached from the main electricity grid in Ethiopia. The wind energy potential of four typical locations has been assessed in a previous article. The solar potential has also been investigated and the results are presented in detail in an accompanying article awaiting publication. For one of the sites, Addis Ababa, the results of the investigation are given here in detail. For the other sites, the results are given as sensitivity diagrams only. Based on the findings of the studies into energy potential, a feasibility study has been carried out on how to supply electricity to a model community of 200 families, which comprises 1000 people in total. The community is equipped with a community school and a health post. The electric load consists of both primary and deferrable types and comprises lighting, water pumps, radio receivers, and some clinical equipment. A software tool, Hybrid Optimization Model for Electric Renewables (HOMER) is used for the analysis. The result of the analysis is a list of feasible power supply systems, sorted according to their net present cost. Furthermore, sensitivity diagrams, showing the influence of wind speeds, PV costs, and diesel prices on the optimum solutions are also provided. (author)

The indigenous Sea Gypsy divers of Thailand's west coast: measurement of carbon monoxide in the breathing air.

Science.gov (United States)

Gold, D; Geater, A; Aiyarak, S; Juengpraert, W

1999-07-01

Approximately 400 indigenous divers live and work on Thailand's west coast. They dive with surface supplied air from primitive compressor units mounted on open boats which measure from seven to 11 meters in length. It was suspected that carbon monoxide was present in the breathing air of at least the gasoline-driven compressor units. To determine the presence of carbon monoxide gas in the breathing air, compressed air from the compressor was pumped through the diver air supply hose through a plenum (monitoring) chamber established on the boat. After a compressor warm-up of 15 minutes, the diving air was measured with the boat at eight different bearings to the wind, each 45 degrees apart at intervals of five minutes. Three of the four gasoline-driven compressor units tested showed presence of carbon monoxide in the breathing air. One diesel-driven unit showed a very low concentration of carbon monoxide (3-4 ppm) and six diesel-driven units showed no detectable carbon monoxide. Although not tested, diesel exhaust emissions could also enter the breathing air by the same route. A locally made modification to the compressor air intake was designed and successfully tested on one gasoline-driven compressor unit. An information sheet on the hazards of carbon monoxide as well as on the modification has been developed for distribution among the villages.

Study into the Potential and Feasibility of a Standalone Solar-Wind Hybrid Electric Energy Supply System

Energy Technology Data Exchange (ETDEWEB)

Bekele, Getachew

2009-12-15

specific to the sites in question. Based on the sunshine duration data, the monthly average daily sunshine amount for each of the places has also been computed and given in a form of plot. Through additional work on the results of the calculations, the solar energy potential has been given in the form of solar radiation plots for each of the selected sites. As expected, the results indicated an abundance of solar energy potential. It is based on the promising findings of these two energy resource potentials, wind and solar, that the feasibility study for a standalone solar-wind hybrid energy supply system has proceeded, targeting the community mentioned earlier. The hybrid system consisted of Wind turbine, Photovoltaic panel, diesel generator and a bank of batteries, with a power conditioning converter included in the system.The hybrid stand-alone supply system is intended to provide electricity toa model community of 200 families with five to six family members in each. The community is equipped with a primary load, a deferrable load, a community school and a health post. An electric load which includes lighting, water pumping, a radio receiver, and some clinical equipment has been suggested. Hybrid Optimization Model for Electric Renewables, HOMER, software has been used for the analysis. The average wind speed and average solar radiation calculated from the data for all of the selected sites has been used to input into the software. The hybrid system design is approached in three different ways. The first approach is to include within the hybrid system those components which are locally available, without giving special attention to their efficiencies and proceed with the design work. The second approach is to thoroughly search the market for the best and most efficient technological products and to select the best components for the analysis. A third approach considered in an attempt of cost minimization is to see if a self-contained type of design can be a better

AIRMaster: Compressed air system audit software

International Nuclear Information System (INIS)

Wheeler, G.M.; Bessey, E.G.; McGill, R.D.; Vischer, K.

1997-01-01

The project goal was to develop a software tool, AIRMaster, and a methodology for performing compressed air system audits. AIRMaster and supporting manuals are designed for general auditors or plant personnel to evaluate compressed air system operation with simple instrumentation during a short-term audit. AIRMaster provides a systematic approach to compressed air system audits, analyzing collected data, and reporting results. AIRMaster focuses on inexpensive Operation and Maintenance (O and M) measures, such as fixing air leaks and improving controls that can significantly improve performance and reliability of the compressed air system, without significant risk to production. An experienced auditor can perform an audit, analyze collected data, and produce results in 2--3 days. AIRMaster reduces the cost of an audit, thus freeing funds to implement recommendations. The AIRMaster package includes an Audit Manual, Software and User's manual, Analysis Methodology Manual, and a Case Studies summary report. It also includes a Self-Guided Tour booklet to help users quickly screen a plant for efficiency improvement potentials, and an Industrial Compressed Air Systems Energy Efficiency Guidebook. AIRMaster proved to be a fast and effective audit tool. In sever audits AIRMaster identified energy savings of 4,056,000 kWh, or 49.2% of annual compressor energy use, for a cost savings of $152,000. Total implementation costs were $94,700 for a project payback period of 0.6 years. Available airflow increased between 11% and 51% of plant compressor capacity, leading to potential capital benefits from 40% to 230% of first year energy savings

Developing a dynamic control system for mine compressed air networks

OpenAIRE

Van Heerden, S.W.; Pelzer, R.; Marais, J.H.

2014-01-01

Mines in general, make use of compressed air systems for daily operational activities. Compressed air on mines is traditionally distributed via compressed air ring networks where multiple shafts are supplied with compressed air from an integral system. These compressed air networks make use of a number of compressors feeding the ring from various locations in the network. While these mines have sophisticated control systems to control these compressors, they are not dynamic systems. Compresso...

A novel hybrid approach for predicting wind farm power production based on wavelet transform, hybrid neural networks and imperialist competitive algorithm

International Nuclear Information System (INIS)

Aghajani, Afshin; Kazemzadeh, Rasool; Ebrahimi, Afshin

2016-01-01

Highlights: • Proposing a novel hybrid method for short-term prediction of wind farms with high accuracy. • Investigating the prediction accuracy for proposed method in comparison with other methods. • Investigating the effect of six types of parameters as input data on predictions. • Comparing results for 6 & 4 types of the input parameters – addition of pressure and air humidity. - Abstract: This paper proposes a novel hybrid approach to forecast electric power production in wind farms. Wavelet transform (WT) is employed to filter input data of wind power, while radial basis function (RBF) neural network is utilized for primary prediction. For better predictions the main forecasting engine is comprised of three multilayer perceptron (MLP) neural networks by different learning algorithms of Levenberg–Marquardt (LM), Broyden–Fletcher–Goldfarb–Shanno (BFGS), and Bayesian regularization (BR). Meta-heuristic technique Imperialist Competitive Algorithm (ICA) is used to optimize neural networks’ weightings in order to escape from local minima. In the forecast process, the real data of wind farms located in the southern part of Alberta, Canada, are used to train and test the proposed model. The data are a complete set of six meteorological and technical characteristics, including wind speed, wind power, wind direction, temperature, pressure, and air humidity. In order to demonstrate the efficiency of the proposed method, it is compared with several other wind power forecast techniques. Results of optimizations indicate the superiority of the proposed method over the other mentioned techniques; and, forecasting error is remarkably reduced. For instance, the average normalized root mean square error (NRMSE) and average mean absolute percentage error (MAPE) are respectively 11% and 14% lower for the proposed method in 1-h-ahead forecasts over a 24-h period with six types of input than those for the best of the compared models.

Efficiency of Compressed Air Energy Storage

DEFF Research Database (Denmark)

Elmegaard, Brian; Brix, Wiebke

2011-01-01

The simplest type of a Compressed Air Energy Storage (CAES) facility would be an adiabatic process consisting only of a compressor, a storage and a turbine, compressing air into a container when storing and expanding when producing. This type of CAES would be adiabatic and would if the machines...... were reversible have a storage efficiency of 100%. However, due to the specific capacity of the storage and the construction materials the air is cooled during and after compression in practice, making the CAES process diabatic. The cooling involves exergy losses and thus lowers the efficiency...... of the storage significantly. The efficiency of CAES as an electricity storage may be defined in several ways, we discuss these and find that the exergetic efficiency of compression, storage and production together determine the efficiency of CAES. In the paper we find that the efficiency of the practical CAES...

Experimental study on combustion and emission characteristics of a diesel engine fueled with 2,5-dimethylfuran–diesel, n-butanol–diesel and gasoline–diesel blends

International Nuclear Information System (INIS)

Chen, Guisheng; Shen, Yinggang; Zhang, Quanchang; Yao, Mingfa; Zheng, Zunqing; Liu, Haifeng

2013-01-01

In the paper, combustion and emissions of a multi-cylinder CI (compression-ignition) engine fueled with DMF–diesel, n-butanol–diesel and gasoline–diesel blends were experimentally investigated, and fuel characteristics of DMF, n-butanol and gasoline were compared. Diesel was used as the base fuel. And 30% of DMF, n-butanol and gasoline were blended with the base fuel by volume respectively, referred to as D30, B30 and G30. Results show that compared to B30 and G30, D30 has longer ignition delay because of lower cetane number, which leads to faster burning rate and higher pressure rise rate. With increasing EGR (exhaust gas recirculation) rate, D30 gets the lowest soot emissions, and extended ignition delay and fuel oxygen are two key factors reducing soot emissions, and ignition delay has greater effects than fuel oxygen on soot reduction. In addition, D30 and B30 improve the trade-off of NO x -soot remarkably and extend low-emission region without deteriorating fuel efficiency by utilizing medium EGR rates ( x , THC and CO emissions and BSFC, but reduce soot greatly. • Fuel oxygen is more efficient than air oxygen while ignition delay has greater effects than fuel oxygen to reduce soot. • As diesel additive, DMF is superior to n-butanol and gasoline for reducing soot emissions. • Using DMF–diesel blends combined with medium EGR may be a better way to meet future emission standards

Oxidative desulfurization of diesel with TBHP/isobutyl aldehyde/air oxidation system

Energy Technology Data Exchange (ETDEWEB)

Guo, Wei; Wang, Chengyong; Lin, Peng; Lu, Xiaoping [Institute of Sonochemical Engineering, Nanjing University of Technology, Nanjing 210009, Jiangsu (China)

2011-01-15

Oxidative desulfurization of hydrogenation diesel (40 mL) was studied using air as oxidant, tert-butyl hydroperoxide (TBHP) as radical initiator at ambient pressure and moderate temperature in the presence of isobutyl aldehyde. TBHP could accelerate the production of carbonyl radical and its peroxidation. When the molar fraction of TBHP was 5 mmol, the conversion of DBT could reach 96.1% in the present of 20 mmol isobutyl aldehyde and air, which was more than that of 85.5% without initiator. The air was an effective oxidant and acetonitrile was an optimal solvent in this process. The sulfur content of the hydrogenation diesel could be reduced from 403 to 13 ppm (96.8% removed) under the synergistic effect of air, TBHP and isobutyl aldehyde. (author)

Adiabatic liquid piston compressed air energy storage

Energy Technology Data Exchange (ETDEWEB)

Petersen, Tage [Danish Technological Institute, Aarhus (Denmark); Elmegaard, B. [Technical Univ. of Denmark. DTU Mechanical Engineering, Kgs. Lyngby (Denmark); Schroeder Pedersen, A. [Technical Univ. of Denmark. DTU Energy Conversion, Risoe Campus, Roskilde (Denmark)

2013-01-15

This project investigates the potential of a Compressed Air Energy Storage system (CAES system). CAES systems are used to store mechanical energy in the form of compressed air. The systems use electricity to drive the compressor at times of low electricity demand with the purpose of converting the mechanical energy into electricity at times of high electricity demand. Two such systems are currently in operation; one in Germany (Huntorf) and one in the USA (Macintosh, Alabama). In both cases, an underground cavern is used as a pressure vessel for the storage of the compressed air. Both systems are in the range of 100 MW electrical power output with several hours of production stored as compressed air. In this range, enormous volumes are required, which make underground caverns the only economical way to design the pressure vessel. Both systems use axial turbine compressors to compress air when charging the system. The compression leads to a significant increase in temperature, and the heat generated is dumped into the ambient. This energy loss results in a low efficiency of the system, and when expanding the air, the expansion leads to a temperature drop reducing the mechanical output of the expansion turbines. To overcome this, fuel is burned to heat up the air prior to expansion. The fuel consumption causes a significant cost for the storage. Several suggestions have been made to store compression heat for later use during expansion and thereby avoid the use of fuel (so called Adiabatic CAES units), but no such units are in operation at present. The CAES system investigated in this project uses a different approach to avoid compression heat loss. The system uses a pre-compressed pressure vessel full of air. A liquid is pumped into the bottom of the vessel when charging and the same liquid is withdrawn through a turbine when discharging. In this case, the liquid works effectively as a piston compressing the gas in the vessel, hence the name &apos

Microbiological contamination of compressed air used in dentistry: an investigation.

Science.gov (United States)

Conte, M; Lynch, R M; Robson, M G

2001-11-01

The purpose of this preliminary investigation was twofold: 1) to examine the possibility of cross-contamination between a dental-evacuation system and the compressed air used in dental operatories and 2) to capture and identify the most common microflora in the compressed-air supply. The investigation used swab, water, and air sampling that was designed to track microorganisms from the evacuation system, through the air of the mechanical room, into the compressed-air system, and back to the patient. Samples taken in the vacuum system, the air space in the mechanical room, and the compressed-air storage tank had significantly higher total concentrations of bacteria than the outside air sampled. Samples of the compressed air returning to the operatory were found to match the outside air sample in total bacteria. It was concluded that the air dryer may have played a significant role in the elimination of microorganisms from the dental compressed-air supply.

ANALYSING SOLAR-WIND HYBRID POWER GENERATING SYSTEM

Directory of Open Access Journals (Sweden)

Mustafa ENGİN

2005-02-01

Full Text Available In this paper, a solar-wind hybrid power generating, system that will be used for security lighting was designed. Hybrid system was installed and solar cells, wind turbine, battery bank, charge regulators and inverter performance values were measured through the whole year. Using measured values of overall system efficiency, reliability, demanded energy cost per kWh were calculated, and percentage of generated energy according to resources were defined. We also include in the paper a discussion of new strategies to improve hybrid power generating system performance and demanded energy cost per kWh.

40 CFR 86.313-79 - Air flow measurement specifications; diesel engines.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Air flow measurement specifications... Procedures § 86.313-79 Air flow measurement specifications; diesel engines. (a) The air flow measurement... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES...

Experimental investigation of gasoline compression ignition combustion in a light-duty diesel engine

Science.gov (United States)

Loeper, C. Paul

Due to increased ignition delay and volatility, low temperature combustion (LTC) research utilizing gasoline fuel has experienced recent interest [1-3]. These characteristics improve air-fuel mixing prior to ignition allowing for reduced emissions of nitrogen oxides (NOx) and soot (or particulate matter, PM). Computational fluid dynamics (CFD) results at the University of Wisconsin-Madison's Engine Research Center (Ra et al. [4, 5]) have validated these attributes and established baseline operating parameters for a gasoline compression ignition (GCI) concept in a light-duty diesel engine over a large load range (3-16 bar net IMEP). In addition to validating these computational results, subsequent experiments at the Engine Research Center utilizing a single cylinder research engine based on a GM 1.9-liter diesel engine have progressed fundamental understanding of gasoline autoignition processes, and established the capability of critical controlling input parameters to better control GCI operation. The focus of this thesis can be divided into three segments: 1) establishment of operating requirements in the low-load operating limit, including operation sensitivities with respect to inlet temperature, and the capabilities of injection strategy to minimize NOx emissions while maintaining good cycle-to-cycle combustion stability; 2) development of novel three-injection strategies to extend the high load limit; and 3) having developed fundamental understanding of gasoline autoignition kinetics, and how changes in physical processes (e.g. engine speed effects, inlet pressure variation, and air-fuel mixture processes) affects operation, develop operating strategies to maintain robust engine operation. Collectively, experimental results have demonstrated the ability of GCI strategies to operate over a large load-speed range (3 bar to 17.8 bar net IMEP and 1300-2500 RPM, respectively) with low emissions (NOx and PM less than 1 g/kg-FI and 0.2 g/kg-FI, respectively), and low

Alternatives to Diesel Fuel in California - Fuel Cycle Energy and Emission Effects of Possible Replacements Due to the TAC Diesel Particulate Decision; FINAL

International Nuclear Information System (INIS)

Christopher L. Saraicks; Donald M. Rote; Frank Stodolsky; James J. Eberhardt

2000-01-01

Limitations on petroleum-based diesel fuel in California could occur pursuant to the 1998 declaration by California's Air Resources Board (CARB) that the particulate matter component of diesel exhaust is a carcinogen, therefore a toxic air contaminant (TAC) subject to the state's Proposition 65. It is the declared intention of CARB not to ban or restrict diesel fuel, per se, at this time. Assuming no total ban, Argonne National Laboratory (ANL) explored two feasible ''mid-course'' strategies, each of which results in some degree of (conventional) diesel displacement. In the first case, with substantial displacement of compression ignition by spark ignition engines, diesel fuel is assumed admissible for ignition assistance as a pilot fuel in natural gas (NG)-powered heavy-duty vehicles. Gasoline demand in California increases by 32.2 million liters (8.5 million gallons) per day overall, about 21 percent above projected 2010 baseline demand. Natural gas demand increases by 13.6 million diesel liter (3.6 million gallon) equivalents per day, about 7 percent above projected (total) consumption level. In the second case, ressionignition engines utilize substitutes for petroleum-based diesel having similar ignition and performance properties. For each case we estimated localized air emission plus generalized greenhouse gas and energy changes. Fuel replacement by di-methyl ether yields the greatest overall reduction in NOx emissions, though all scenarios bring about PM10 reductions relative to the 2010 baseline, with greatest reductions from the first case described above and the least from fuel replacement by Fischer-Tropsch synthetic diesel. Economic implications of vehicle and engine replacement were not formally evaluated

Ultrafine particle air pollution inside diesel-propelled passenger trains.

Science.gov (United States)

Abramesko, Victoria; Tartakovsky, Leonid

2017-07-01

Locomotives with diesel engines are used worldwide and are an important source of air pollution. Pollutant emissions by locomotive engines affect the air quality inside passenger trains. This study is aimed at investigating ultrafine particle (UFP) air pollution inside passenger trains and providing a basis for assessing passenger exposure to this pollutant. The concentrations of UFPs inside the carriages of push-pull trains are dramatically higher when the train operates in pull mode. This clearly shows that locomotive engine emissions are a dominant factor in train passengers' exposure to UFPs. The highest levels of UFP air pollution are observed inside the carriages of pull trains close to the locomotive. In push mode, the UFP number concentrations were lower by factors of 2.6-43 (depending on the carriage type) compared to pull mode. The UFP concentrations are substantially lower in diesel multiple-unit trains than in trains operating in pull mode. A significant influence of the train movement regime on the UFP NC inside a carriage is observed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Techno-economic analysis of an optimized photovoltaic and diesel generator hybrid power system for remote houses in a tropical climate

International Nuclear Information System (INIS)

Ismail, M.S.; Moghavvemi, M.; Mahlia, T.M.I.

2013-01-01

Highlights: ► We analyzed solar data in the location under consideration. ► We developed a program to simulate the operation of the PV-diesel generator hybrid system. ► We analyzed different scenarios to select and design the optimal system. ► It is cost effective to power houses in remote areas with such hybrid systems. ► The hybrid system had lower CO 2 emissions compared to a diesel generator only operation. - Abstract: A techno-economic analysis and the design of a complete hybrid system, consisting of photovoltaic (PV) panels, a battery system and a diesel generator as a backup power source for a typical Malaysian village household is presented in this paper. The specifications of the different components constructing the hybrid system were also determined. A scenario depending on a standalone PV and other scenario depending on a diesel generator only were also analyzed. A simulation program was developed to simulate the operation of these different scenarios. The scenario that achieves the minimum cost while meeting the load requirement was selected. The optimal tilt angle of the PV panels in order to increase the generated energy was obtained using genetic algorithm. In addition, sensitivity analysis was undertaken to evaluate the effect of change of some parameters on the cost of energy. The results indicated that the optimal scenario is the one that consists of a combination of the PV panels, battery bank and a diesel generator. Powering a rural house using this hybrid system is advantageous as it decreases operating cost, increases efficiencies, and reduces pollutant emissions

Energy performance analysis for a photovoltaic, diesel, battery hybrid power supply system

CSIR Research Space (South Africa)

Tazvinga, Henerica

2010-03-01

Full Text Available This paper looks at an energy performance analysis for a photovoltaic, diesel, and battery hybrid power supply system. The procedure starts by the identification of the hourly load requirements for a typical target consumer and the concept of load...

Trigenerative micro compressed air energy storage: Concept and thermodynamic assessment

International Nuclear Information System (INIS)

Facci, Andrea L.; Sánchez, David; Jannelli, Elio; Ubertini, Stefano

2015-01-01

Highlights: • The trigenerative-CAES concept is introduced. • The thermodynamic feasibility of the trigenerative-CAES is assessed. • The effects of the relevant parameter on the system performances are dissected. • Technological issues on the trigenerative-CAES are highlighted. - Abstract: Energy storage is a cutting edge front for renewable and sustainable energy research. In fact, a massive exploitation of intermittent renewable sources, such as wind and sun, requires the introduction of effective mechanical energy storage systems. In this paper we introduce the concept of a trigenerative energy storage based on a compressed air system. The plant in study is a simplified design of the adiabatic compressed air energy storage and accumulates mechanical and thermal (both hot and cold) energy at the same time. We envisage the possibility to realize a relatively small size trigenerative compressed air energy storage to be placed close to the energy demand, according to the distributed generation paradigm. Here, we describe the plant concept and we identify all the relevant parameters influencing its thermodynamic behavior. Their effects are dissected through an accurate thermodynamic model. The most relevant technological issues, such as the guidelines for a proper choice of the compressor, expander and heat exchangers are also addressed. Our results show that T-CAES may have an interesting potential as a distributed system that combines electricity storage with heat and cooling energy production. We also show that the performances are significantly influenced by some operating and design parameters, whose feasibility in real applications must be considered.

Feasibility of waste to Bio-diesel production via Nuclear-Biomass hybrid model. System dynamics analysis

International Nuclear Information System (INIS)

Nam, Hoseok; Kasada, Ryuta; Konishi, Satoshi

2017-01-01

Nuclear-Biomass hybrid system which takes waste biomass from municipal, agricultural area, and forest as feedstock produces Bio-diesel fuel from synthesis gas generated by endothermic pyrolytic gasification using high temperature nuclear heat. Over 900 degree Celsius of exterior thermal heat from nuclear reactors, Very High Temperature Reactor (VHTR) and some other heat sources, bring about waste biomass gasification to produce maximum amount of chemical energy from feedstock. Hydrogen from Biomass gasification or Bio-diesel as the product of Fischer-Tropsch reaction following it provide fuels for transport sector. Nuclear-Biomass hybrid system is a new alternatives to produce more energy generating synergy effects by efficiently utilizing the high temperature heat from nuclear reactor that might be considerably wasted by thermal cycle, and also energy loss from biomass combustion or biochemical processes. System Dynamics approach is taken to analyze low-carbon synthesis fuel, Bio-diesel, production with combination of carbon monoxide and hydrogen from biomass gasification. Feedstock cost considering collection, transportation, storage and facility for biomass gasification impacts the economic feasibility of this model. This paper provides the implication of practical nuclear-biomass hybrid system application with feedstock supply chain through evaluation of economic feasibility. (author)

Conceptual evaluation of hybrid energy system comprising wind-biomass-nuclear plants for load balancing and for production of renewable synthetic transport fuels

International Nuclear Information System (INIS)

Carlsson, Johan; Purvins, Arturs; Papaioannou, Ioulia T.; Shropshire, David; Cherry, Robert S.

2014-01-01

Future energy systems will increasingly need to integrate variable renewable energy in order to reduce greenhouse gas emissions from power production. Addressing this trend the present paper studies how a hybrid energy systems comprising aggregated wind farms, a biomass processing plant, and a nuclear cogeneration plant could support high renewable energy penetration. The hybrid energy system operates so that its electrical output tends to meet demand. This is achieved mainly through altering the heat-to-power ratio of the nuclear reactor and by using excess electricity for hydrogen production through electrolysis. Hybrid energy systems with biomass treatment processes, i.e. drying, torrefaction, pyrolysis and synthetic fuel production were evaluated. It was shown that the studied hybrid energy system comprising a 1 GWe wind farm and a 347 MWe nuclear reactor could closely follow the power demand profile with a standard deviation of 34 MWe. In addition, on average 600 m"3 of bio-gasoline and 750 m"3 bio-diesel are produced daily. The reduction of greenhouse gas emissions of up to 4.4 MtCO_2eq annually compared to power generation and transport using conventional fossil fuel sources. (author)

Improved hybrid isolator with maglev actuator integrated in air spring for active-passive isolation of ship machinery vibration

Science.gov (United States)

Li, Yan; He, Lin; Shuai, Chang-geng; Wang, Chun-yu

2017-10-01

A hybrid isolator consisting of maglev actuator and air spring is proposed and developed for application in active-passive vibration isolation system of ship machinery. The dynamic characteristics of this hybrid isolator are analyzed and tested. The stability and adaptability of this hybrid isolator to shock and swing in the marine environment are improved by a compliant gap protection technique and a disengageable suspended structure. The functions of these new engineering designs are proved by analytical verification and experimental validation of the designed stiffness of such a hybrid isolator, and also by shock adaptability testing of the hybrid isolator. Finally, such hybrid isolators are installed in an engineering mounting loaded with a 200-kW ship diesel generator, and the broadband and low-frequency sinusoidal isolation performance is tested.

Real world CO2 and NOx emissions from 149 Euro 5 and 6 diesel, gasoline and hybrid passenger cars.

Science.gov (United States)

O'Driscoll, Rosalind; Stettler, Marc E J; Molden, Nick; Oxley, Tim; ApSimon, Helen M

2018-04-15

In this study CO 2 and NO x emissions from 149 Euro 5 and 6 diesel, gasoline and hybrid passenger cars were compared using a Portable Emissions Measurement System (PEMS). The models sampled accounted for 56% of all passenger cars sold in Europe in 2016. We found gasoline vehicles had CO 2 emissions 13-66% higher than diesel. During urban driving, the average CO 2 emission factor was 210.5 (sd. 47) gkm -1 for gasoline and 170.2 (sd. 34) gkm -1 for diesel. Half the gasoline vehicles tested were Gasoline Direct Injection (GDI). Euro 6 GDI engines cars. The average urban NO x emission from Euro 6 diesel vehicles 0.44 (sd. 0.44) gkm -1 was 11 times higher than for gasoline 0.04 (sd. 0.04) gkm -1 . We also analysed two gasoline-electric hybrids which out-performed both gasoline and diesel for NO x and CO 2 . We conclude action is required to mitigate the public health risk created by excessive NO x emissions from modern diesel vehicles. Replacing diesel with gasoline would incur a substantial CO 2 penalty, however greater uptake of hybrid vehicles would likely reduce both CO 2 and NO x emissions. Discrimination of vehicles on the basis of Euro standard is arbitrary and incentives should promote vehicles with the lowest real-world emissions of both NO x and CO 2 . Copyright © 2017 Elsevier B.V. All rights reserved.

A Novel Numerical Algorithm for Optimal Sizing of a Photovoltaic/Wind/Diesel Generator/Battery Microgrid Using Loss of Load Probability Index

Directory of Open Access Journals (Sweden)

Hussein A. Kazem

2013-01-01

Full Text Available This paper presents a method for determining optimal sizes of PV array, wind turbine, diesel generator, and storage battery installed in a building integrated system. The objective of the proposed optimization is to design the system that can supply a building load demand at minimum cost and maximum availability. The mathematical models for the system components as well as meteorological variables such as solar energy, temperature, and wind speed are employed for this purpose. Moreover, the results showed that the optimum sizing ratios (the daily energy generated by the source to the daily energy demand for the PV array, wind turbine, diesel generator, and battery for a system located in Sohar, Oman, are 0.737, 0.46, 0.22, and 0.17, respectively. A case study represented by a system consisting of 30 kWp PV array (36%, 18 kWp wind farm (55%, and 5 kVA diesel generator (9% is presented. This system is supposed to power a 200 kWh/day load demand. It is found that the generated energy share of the PV array, wind farm, and diesel generator is 36%, 55%, and 9%, respectively, while the cost of energy is 0.17 USD/kWh.

Accidental fatal lung injury by compressed air: a case report.

Science.gov (United States)

Rayamane, Anand Parashuram; Pradeepkumar, M V

2015-03-01

Compressed air is being used extensively as a source of energy at industries and in daily life. A variety of fatal injuries are caused by improper and ignorant use of compressed air equipments. Many types of injuries due to compressed air are reported in the literature such as colorectal injury, orbital injury, surgical emphysema, and so on. Most of these injuries are accidental in nature. It is documented that 40 pounds per square inch pressure causes fatal injuries to the ear, eyes, lungs, stomach, and intestine. Openings of body are vulnerable to injuries by compressed air. Death due to compressed air injuries is rarely reported. Many cases are treated successfully by conservative or surgical management. Extensive survey of literature revealed no reports of fatal injury to the upper respiratory tract and lungs caused by compressed air. Here, we are reporting a fatal event of accidental death after insertion of compressed air pipe into the mouth. The postmortem findings are corroborated with the history and discussed in detail.

Hybrid Automotive Engine Using Ethanol-Burning Miller Cycle

Science.gov (United States)

Weinstein, Leonard

2004-01-01

A proposed hybrid (internal-combustion/ electric) automotive engine system would include as its internal-combustion subsystem, a modified Miller-cycle engine with regenerative air preheating and with autoignition like that of a Diesel engine. The fuel would be ethanol and would be burned lean to ensure complete combustion. Although the proposed engine would have a relatively low power-to-weight ratio compared to most present engines, this would not be the problem encountered if this engine were used in a non-hybrid system since hybrid systems require significantly lower power and thus smaller engines than purely internal-combustion-engine-driven vehicles. The disadvantage would be offset by the advantages of high fuel efficiency, low emission of nitrogen oxides and particulate pollutants, and the fact that ethanol is a renewable fuel. The original Miller-cycle engine, named after its inventor, was patented in the 1940s and is the basis of engines used in some modern automobiles, but is not widely known. In somewhat oversimplified terms, the main difference between a Miller-cycle engine and a common (Otto-cycle) automobile engine is that the Miller-cycle engine has a longer expansion stroke while retaining the shorter compression stroke. This is accomplished by leaving the intake valve open for part of the compression stroke, whereas in the Otto cycle engine, the intake valve is kept closed during the entire compression stroke. This greater expansion ratio makes it possible to extract more energy from the combustion process without expending more energy for compression. The net result is greater efficiency. In the proposed engine, the regenerative preheating would be effected by running the intake air through a heat exchanger connected to the engine block. The regenerative preheating would offer two advantages: It would ensure reliable autoignition during operation at low ambient temperature and would help to cool the engine, thereby reducing the remainder of the

Roofbolters with compressed-air rotators

Science.gov (United States)

Lantsevich, MA; Repin Klishin, AA, VI; Kokoulin, DI

2018-03-01

The specifications of the most popular roofbolters of domestic and foreign manufacture currently in operation in coal mines are discussed. Compressed-air roofbolters SAP and SAP2 designed at the Institute of Mining are capable of drilling in hard rocks. The authors describe the compressed-air rotator of SAP2 roofbolter with alternate motion rotors. From the comparative analysis of characteristics of SAP and SAP 2 roofbolters, the combination of high-frequency axial and rotary impacts on a drilling tool in SAP2 ensure efficient drilling in rocks with the strength up to 160 MPa.

Sistem Kontrol Frekuensi Optimal Pada Pembangkit Hibrid Wind-Diesel Dengan Imperialist Competitive Algorithm

Directory of Open Access Journals (Sweden)

Muhammad Ruswandi Djalal

2017-10-01

Full Text Available Frequency load arrangement on wind-diesel hybrid power plants (PLTH becomes a very important thing in order to support the performance of the plant. One method of setting the load frequency is to use additional controllers such as Proportional Integral Derivative (PID. The use of PID also has its own problems, such as adjusting the value of unoptimal gain. In practice the PID gain is observed by trial-error, making it difficult to obtain the optimal value of the PID. In this research, we proposed an intelligent method of Imperialist Competitive Algorithm (ICA in finding the optimal value of PID. The ICA is a smart method inspired by the competition in power struggles. ICA works based on the objective function, which minimizes Integral Time Absolute Error (ITAE. From the results of ICA optimization obtained value Kp = 63.1087, Ki = 43.2682, Kd = 9.6038. Response system, among others, for the settling time of 5.8 and overshoot of -9.098e-05 to 1.111e-09 pu which is the smallest settling time and overshoot value. Pengaturan frekuensi beban pada pembangkit listrik tenaga hibrid wind-diesel (PLTH menjadi hal yang sangat penting agar dapat menunjang kinerja pembangkit. Salah satu metode pengaturan frekuensi beban adalah menggunakan kontroler tambahan seperti Proporsional Integral Derivatif (PID. Penggunaan PID juga mempunyai permasalahan tersendiri, seperti penyetelan nilai gain yang tidak optimal. Dalam penerapannya gain PID ditala secara trial-error, sehingga sulit untuk mendapatkan nilai optimal dari PID. Dalam penelitian ini, diusulkan sebuah metode cerdas yaitu Imperialist Competitive Algorithm (ICA dalam mencari nilai optimal dari PID. ICA merupakan metode cerdas yang terinspirasi dari kompetisi dalam memperebutkan kekuasaan. ICA bekerja berdasarkan fungsi objektif, yaitu meminimalkan Integral Time Absolute Error (ITAE. Dari hasil optimasi ICA didapatkan nilai Kp = 63.1087, Ki = 43.2682, Kd = 9.6038. Respons sistem yang diperoleh antara lain

A hybrid measure-correlate-predict method for long-term wind condition assessment

International Nuclear Information System (INIS)

Zhang, Jie; Chowdhury, Souma; Messac, Achille; Hodge, Bri-Mathias

2014-01-01

Highlights: • A hybrid measure-correlate-predict (MCP) methodology with greater accuracy is developed. • Three sets of performance metrics are proposed to evaluate the hybrid MCP method. • Both wind speed and direction are considered in the hybrid MCP method. • The best combination of MCP algorithms is determined. • The developed hybrid MCP method is uniquely helpful for long-term wind resource assessment. - Abstract: This paper develops a hybrid measure-correlate-predict (MCP) strategy to assess long-term wind resource variations at a farm site. The hybrid MCP method uses recorded data from multiple reference stations to estimate long-term wind conditions at a target wind plant site with greater accuracy than is possible with data from a single reference station. The weight of each reference station in the hybrid strategy is determined by the (i) distance and (ii) elevation differences between the target farm site and each reference station. In this case, the wind data is divided into sectors according to the wind direction, and the MCP strategy is implemented for each wind direction sector separately. The applicability of the proposed hybrid strategy is investigated using five MCP methods: (i) the linear regression; (ii) the variance ratio; (iii) the Weibull scale; (iv) the artificial neural networks; and (v) the support vector regression. To implement the hybrid MCP methodology, we use hourly averaged wind data recorded at five stations in the state of Minnesota between 07-01-1996 and 06-30-2004. Three sets of performance metrics are used to evaluate the hybrid MCP method. The first set of metrics analyze the statistical performance, including the mean wind speed, wind speed variance, root mean square error, and mean absolute error. The second set of metrics evaluate the distribution of long-term wind speed; to this end, the Weibull distribution and the Multivariate and Multimodal Wind Distribution models are adopted. The third set of metrics analyze

Volatile organic compounds in a residential and commercial urban area with a diesel, compressed natural gas and oxygenated gasoline vehicular fleet.

Science.gov (United States)

Martins, Eduardo Monteiro; Arbilla, Graciela; Gatti, Luciana Vanni

2010-02-01

Air samples were collected in a typical residential and commercial area in Rio de Janeiro, Brazil, where buses and trucks use diesel and light duty vehicles use compressed natural gas, ethanol, and gasohol (gasoline blended with ethanol) as fuel. A total of 66 C3-C12 volatile organic compounds (VOCs) were identified. The most abundant compounds, on a mass concentration basis, included propane, isobutane, i-pentane, m,p-xylene, 1,3,5-trimethylbenzene, toluene, styrene, ethylbenzene, isopropylbenzene, o-xylene and 1,2,4-trimethylbenzene. Two VOCs photochemical reactivity rankings are presented: one involves reaction with OH and the other involves production of ozone.

Theoretical modeling of combustion characteristics and performance parameters of biodiesel in DI diesel engine with variable compression ratio

Energy Technology Data Exchange (ETDEWEB)

Al-Dawody, Mohamed F.; Bhatti, S.K. [Department of Mechanical Engineering, Andhra University (India)

2013-07-01

Increasing of costly and depleting fossil fuels are prompting researchers to use edible as well as non-edible vegetable oils as a promising alternative to petro-diesel fuels. A comprehensive computer code using ''Quick basic'' language was developed for the diesel engine cycle to study the combustion and performance characteristics of a single cylinder, four stroke, direct injection diesel engine with variable compression ratio. The engine operates on diesel fuel and 20% (mass basis) of biodiesel (derived from soybean oil) blended with diesel. Combustion characteristics such as cylinder pressure, heat release fraction, heat transfer and performance characteristics such as brake power; and brake specific fuel consumption (BSFC) were analyzed. On the basis of the first law of thermodynamics the properties at each degree crank angle was calculated. Wiebe function is used to calculate the instantaneous heat release rate. The computed results are validated through the results obtained in the simulation Diesel-rk software.

FY 1998 Report on development of large-scale wind power generation systems. Research of wind turbines for storm worthy and easy construction; 1998 nendo ogata furyoku hatsuden system kaihatsu. Taikyofu kensetsu yoigata fusha ni kansuru chosa kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

The research and development statuses in various countries are surveyed, to have useful information to draw the future R and D directions for wind turbines resistant to storms and easy construction. Greece has sites suitable for wind power generation in mountainous districts, and is developing the systems while taking the characteristic weather conditions into consideration. The country provides information regarding aerodynamic/structural design methods for wind turbine blades applicable to turbulent wind generated by complex terrain, and wind assessment and analyses in complex terrain. In India, on-the-spot surveys are made at the cyclone-attacked wind farms. One of the areas on which the USA is putting emphasis is development of small-size wind turbines and wind-diesel hybrid systems for developing countries and independent grid systems in remote areas. Australia is constructing wind-diesel hybrid systems to be connected to a number of independent grid systems in its western area. In Europe, information is collected for the advanced aerodynamic analysis, construction of offshore wind turbines, and production engineering and facilities for blades and other components from Vestas and N.E.G. Micon as the leading wind turbine makers. (NEDO)

Feasibility study of renewable energy resources and optimization of electrical hybrid energy systems: Case study for Islamic Azad University, South Tehran Branch, Iran

Directory of Open Access Journals (Sweden)

Fazelpour Farivar

2017-01-01

Full Text Available Renewable energies are increasingly seen as the best solution to a growing global population demanding affordable access to electricity while reducing the need for fossil fuels. Country of Iran has vast untapped solar, wind, geothermal and hydroelectric sources that hold the potential to meet domestic needs. Renewable energy is also essential to Iran as it will curb massive air pollution. In this paper economical and feasibility study of various hybrid systems are performed by using HOMER software model for supplying electricity to the Engineering Department of Islamic Azad University. For this study, annual electricity demand of the university is 1,174,935 kWh with a peak demand of about 331 kW, average wind speeds, based on hourly data during the period of eleven years (2000-2010, are between 3 to 5 m/s in all months of the year. For solar radiation, six models are evaluated to select the best model for estimation of the daily global solar radiation (GSR on a horizontal surface in the study location. Among these six models, H/HO=a+b (S/S0+ c(S/S02 is chosen as the most optimum model for estimating solar irradiation. The results indicate that among the three hybrid systems for fulfilling electrical energy needs, the Wind/Diesel/Battery hybrid system with 9 wind turbines (20 kW, one diesel generator (300 kW, 50 batteries, and 50 kW power converters with net present cost of $4,281,800 and cost of energy of 0.285 $/kWh is the most economically efficient hybrid system. (based on 2015 US dollar.

41 CFR 50-204.8 - Use of compressed air.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 1 2010-07-01 2010-07-01 true Use of compressed air. 50-204.8 Section 50-204.8 Public Contracts and Property Management Other Provisions Relating to Public... General Safety and Health Standards § 50-204.8 Use of compressed air. Compressed air shall not be used for...

A Coupled Thermo-Hydro-Mechanical Model of Jointed Hard Rock for Compressed Air Energy Storage

Directory of Open Access Journals (Sweden)

Xiaoying Zhuang

2014-01-01

Full Text Available Renewable energy resources such as wind and solar are intermittent, which causes instability when being connected to utility grid of electricity. Compressed air energy storage (CAES provides an economic and technical viable solution to this problem by utilizing subsurface rock cavern to store the electricity generated by renewable energy in the form of compressed air. Though CAES has been used for over three decades, it is only restricted to salt rock or aquifers for air tightness reason. In this paper, the technical feasibility of utilizing hard rock for CAES is investigated by using a coupled thermo-hydro-mechanical (THM modelling of nonisothermal gas flow. Governing equations are derived from the rules of energy balance, mass balance, and static equilibrium. Cyclic volumetric mass source and heat source models are applied to simulate the gas injection and production. Evaluation is carried out for intact rock and rock with discrete crack, respectively. In both cases, the heat and pressure losses using air mass control and supplementary air injection are compared.

Analysis of hybrid energy systems for application in southern Ghana

International Nuclear Information System (INIS)

Adaramola, Muyiwa S.; Agelin-Chaab, Martin; Paul, Samuel S.

2014-01-01

Highlights: • The option of using hybrid energy for electricity in remote areas of Ghana is examined. • The cost of electricity produced by the hybrid system is found to be $0.281/kW h. • The levelized cost of electricity increase by 9% when the PV price is increased from $3000/kW to $7500/kW. - Abstract: Due to advances in renewable energy technologies and increase in oil price, hybrid renewable energy systems are becoming increasingly attractive for power generation applications in remote areas. This paper presents an economic analysis of the feasibility of utilizing a hybrid energy system consisting of solar, wind and diesel generators for application in remote areas of southern Ghana using levelized cost of electricity (LCOE) and net present cost of the system. The annual daily average solar global radiation at the selected site is 5.4 kW h/m 2 /day and the annual mean wind speed is 5.11 m/s. The National Renewable Energy Laboratory’s Hybrid Optimization Model for Electric Renewable (HOMER) software was employed to carry out the present study. Both wind data and the actual load data have been used in the simulation model. It was found that a PV array of 80 kW, a 100 kW wind turbine, two generators with combined capacity of 100 kW, a 60 kW converter/inverter and a 60 Surrette 4KS25P battery produced a mix of 791.1 MW h of electricity annually. The cost of electricity for this hybrid system is found to be $0.281/kW h. Sensitivity analysis on the effect of changes in wind speed, solar global radiation and diesel price on the optimal energy was investigated and the impact of solar PV price on the LCOE for a selected hybrid energy system was also presented

Compressed air massage hastens healing of the diabetic foot.

Science.gov (United States)

Mars, M; Desai, Y; Gregory, M A

2008-02-01

The management of diabetic foot ulcers remains a problem. A treatment modality that uses compressed air massage has been developed as a supplement to standard surgical and medical treatment. Compressed air massage is thought to improve local tissue oxygenation around ulcers. The aim of this study was to determine whether the addition of compressed air massage influences the rate of healing of diabetic ulcers. Sixty consecutive patients with diabetes, admitted to one hospital for urgent surgical management of diabetic foot ulcers, were randomized into two groups. Both groups received standard medical and surgical management of their diabetes and ulcer. In addition, one group received 15-20 min of compressed air massage, at 1 bar pressure, daily, for 5 days a week, to the foot and the tissue around the ulcer. Healing time was calculated as the time from admission to the time of re-epithelialization. Fifty-seven patients completed the trial; 28 received compressed air massage. There was no difference in the mean age, Wagner score, ulcer size, pulse status, or peripheral sensation in the two groups. The time to healing in the compressed air massage group was significantly reduced: 58.1 +/- 22.3 days (95% confidence interval: 49.5-66.6) versus 82.7 +/- 30.7 days (95% confidence interval: 70.0-94.3) (P = 0.001). No adverse effects in response to compressed air massage were noted. The addition of compressed air massage to standard medical and surgical management of diabetic ulcers appears to enhance ulcer healing. Further studies with this new treatment modality are warranted.

Enhancement of Satellite Image Compression Using a Hybrid (DWT-DCT) Algorithm

Science.gov (United States)

Shihab, Halah Saadoon; Shafie, Suhaidi; Ramli, Abdul Rahman; Ahmad, Fauzan

2017-12-01

Discrete Cosine Transform (DCT) and Discrete Wavelet Transform (DWT) image compression techniques have been utilized in most of the earth observation satellites launched during the last few decades. However, these techniques have some issues that should be addressed. The DWT method has proven to be more efficient than DCT for several reasons. Nevertheless, the DCT can be exploited to improve the high-resolution satellite image compression when combined with the DWT technique. Hence, a proposed hybrid (DWT-DCT) method was developed and implemented in the current work, simulating an image compression system on-board on a small remote sensing satellite, with the aim of achieving a higher compression ratio to decrease the onboard data storage and the downlink bandwidth, while avoiding further complex levels of DWT. This method also succeeded in maintaining the reconstructed satellite image quality through replacing the standard forward DWT thresholding and quantization processes with an alternative process that employed the zero-padding technique, which also helped to reduce the processing time of DWT compression. The DCT, DWT and the proposed hybrid methods were implemented individually, for comparison, on three LANDSAT 8 images, using the MATLAB software package. A comparison was also made between the proposed method and three other previously published hybrid methods. The evaluation of all the objective and subjective results indicated the feasibility of using the proposed hybrid (DWT-DCT) method to enhance the image compression process on-board satellites.

Geothermally Coupled Well-Based Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Davidson, C L [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-01

Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

Geothermally Coupled Well-Based Compressed Air Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Davidson, Casie L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bearden, Mark D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Horner, Jacob A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cabe, James E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Appriou, Delphine [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); McGrail, B. Peter [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-12-20

Previous work by McGrail et al. (2013, 2015) has evaluated the possibility of pairing compressed air energy storage with geothermal resources in lieu of a fossil-fired power generation component, and suggests that such applications may be cost competitive where geology is favorable to siting both the geothermal and CAES components of such a system. Those studies also note that the collocation of subsurface resources that meet both sets of requirements are difficult to find in areas that also offer infrastructure and near- to mid-term market demand for energy storage. This study examines a novel application for the compressed air storage portion of the project by evaluating the potential to store compressed air in disused wells by amending well casings to serve as subsurface pressure vessels. Because the wells themselves would function in lieu of a geologic storage reservoir for the CAES element of the project, siting could focus on locations with suitable geothermal resources, as long as there was also existing wellfield infrastructure that could be repurposed for air storage. Existing wellfields abound in the United States, and with current low energy prices, many recently productive fields are now shut in. Should energy prices remain stagnant, these idle fields will be prime candidates for decommissioning unless they can be transitioned to other uses, such as redevelopment for energy storage. In addition to the nation’s ubiquitous oil and gas fields, geothermal fields, because of their phased production lifetimes, also may offer many abandoned wellbores that could be used for other purposes, often near currently productive geothermal resources. These existing fields offer an opportunity to decrease exploration and development uncertainty by leveraging data developed during prior field characterization, drilling, and production. They may also offer lower-cost deployment options for hybrid geothermal systems via redevelopment of existing well-field infrastructure

Recoil Experiments Using a Compressed Air Cannon

Science.gov (United States)

Taylor, Brett

2006-01-01

Ping-Pong vacuum cannons, potato guns, and compressed air cannons are popular and dramatic demonstrations for lecture and lab. Students enjoy them for the spectacle, but they can also be used effectively to teach physics. Recently we have used a student-built compressed air cannon as a laboratory activity to investigate impulse, conservation of…

Effect of the Ethanol Injection Moment During Compression Stroke on the Combustion of Ethanol - Diesel Dual Direct Injection Engine

Science.gov (United States)

Liang, Yu; Zhou, Liying; Huang, Haomin; Xu, Mingfei; Guo, Mei; Chen, Xin

2018-01-01

A set of GDI system is installed on a F188 single-cylinder, air-cooled and direct injection diesel engine, which is used for ethanol injection, with the injection time controlled by the crank angle signal collected by AVL angle encoder. The injection of ethanol amounts to half of the thermal equivalent of an original diesel fuel. A 3D combustion model is established for the ethanol - diesel dual direct injection engine. Diesel was injected from the original fuel injection system, with a fuel supply advance angle of 20°CA. The ethanol was injected into the cylinder during compression process. Diesel injection began after the completion of ethanol injection. Ethanol injection starting point of 240°CA, 260°CA, 280°CA, 300°CA and 319.4°CA were simulated and analyzed. Due to the different timing of ethanol injection, the ignition of the ethanol mixture when diesel fires, results in non-uniform ignition distribution and flame propagation rate, since the distribution and concentration gradients of the ethanol mixture in the cylinder are different, thus affecting the combustion process. The results show that, when ethanol is injected at 319.4°CA, the combustion heat release rate and the pressure rise rate during the initial stage are the highest. Also, the maximum combustion pressure, with a relatively advance phase, is the highest. In case of later initial ethanol injection, the average temperature in the cylinder during the initial combustion period will have a faster rise. In case of initial injection at 319.4°CA, the average temperature in the cylinder is the highest, followed by 240°CA ethanol injection. In the post-combustion stage, the earlier ethanol injection will result in higher average temperature in the cylinder and more complete fuel combustion. The injection of ethanol at 319.4°CA produces earlier and highest NOX emissions.

Energy storage by compressed air. [using windpowered pumps

Science.gov (United States)

Szego, G. C.

1973-01-01

The feasibility of windpower energy storage by compressed air is considered. The system is comprised of a compressor, a motor, and a pump turbine to store air in caverns or aquifiers. It is proposed that storage of several days worth of compressed air up to 650 pounds per square inch can be used to push the aquifier up closer to the container dome and thus initiate piston action by simply compressing air more and more. More energy can be put into it by pressure increase or pushing back the water in the aquifier. This storage system concept has reheat flexibility and lowest cost effectiveness.

Lower operating cost due to compressed-air recirculation

Energy Technology Data Exchange (ETDEWEB)

Schauwecker, F

1979-01-01

Compressed air containing dirt and aggressive substances may cause damage in pipelines and pneumatic tools, equipment and systems. In consequence, operating costs can be greatly reduced by cleaning and recirculation of compressed air. Compressed-air driers are among the most common systems used for this purpose. Most of these driers are refrigeration driers; adsorption driers are less common. Refrigeration driers consist of a heat exchanger system, a separation system, and a power-controlled refrigerator. The water vapour concentration is proportional to the air temperature; for this reason, the pressure dew point should be as low as possible, i.e. about 1.5/sup 0/C.

Sizing PV-wind hybrid energy system for lighting

Directory of Open Access Journals (Sweden)

Mustafa Engin

2012-09-01

Full Text Available Sizing of wind and photovoltaic generators ensures lower operational costs and therefore, is considered as an important issue. An approach for sizing along with a best management technique for a PV-wind hybrid system with batteries is proposed in this paper, in which the best size for every component of the system could be optimized according to the weather conditions and the load profile. The average hourly values for wind speed and solar radiation for Izmir, Turkey has been used in the design of the systems, along with expected load profile. A hybrid power model is also developed for battery operation according to the power balance between generators and loads used in the software, to anticipate performances for the different systems according to the different weather conditions. The output of the program will display the performance of the system during the year, the total cost of the system, and the best size for the PV-generator, wind generator, and battery capacity. Using proposed procedure, a 1.2 kWp PV-wind hybrid system was designed for Izmir, and simulated and measured results are presented.

Compressed air energy storage system

Science.gov (United States)

Ahrens, Frederick W.; Kartsounes, George T.

1981-01-01

An internal combustion reciprocating engine is operable as a compressor during slack demand periods utilizing excess power from a power grid to charge air into an air storage reservoir and as an expander during peak demand periods to feed power into the power grid utilizing air obtained from the air storage reservoir together with combustible fuel. Preferably the internal combustion reciprocating engine is operated at high pressure and a low pressure turbine and compressor are also employed for air compression and power generation.

Ultra-Short-Term Wind Power Prediction Using a Hybrid Model

Science.gov (United States)

Mohammed, E.; Wang, S.; Yu, J.

2017-05-01

This paper aims to develop and apply a hybrid model of two data analytical methods, multiple linear regressions and least square (MLR&LS), for ultra-short-term wind power prediction (WPP), for example taking, Northeast China electricity demand. The data was obtained from the historical records of wind power from an offshore region, and from a wind farm of the wind power plant in the areas. The WPP achieved in two stages: first, the ratios of wind power were forecasted using the proposed hybrid method, and then the transformation of these ratios of wind power to obtain forecasted values. The hybrid model combines the persistence methods, MLR and LS. The proposed method included two prediction types, multi-point prediction and single-point prediction. WPP is tested by applying different models such as autoregressive moving average (ARMA), autoregressive integrated moving average (ARIMA) and artificial neural network (ANN). By comparing results of the above models, the validity of the proposed hybrid model is confirmed in terms of error and correlation coefficient. Comparison of results confirmed that the proposed method works effectively. Additional, forecasting errors were also computed and compared, to improve understanding of how to depict highly variable WPP and the correlations between actual and predicted wind power.

Comparative evaluation of the effect of sweet orange oil-diesel blend on performance and emissions of a multi-cylinder compression ignition engine

Science.gov (United States)

Rahman, S. M. Ashrafur; Hossain, F. M.; Van, Thuy Chu; Dowell, Ashley; Islam, M. A.; Rainey, Thomas J.; Ristovski, Zoran D.; Brown, Richard J.

2017-06-01

In 2014, global demand for essential oils was 165 kt and it is expected to grow 8.5% per annum up to 2022. Every year Australia produces approximately 1.5k tonnes of essential oils such as tea tree, orange, lavender, eucalyptus oil, etc. Usually essential oils come from non-fatty areas of plants such as the bark, roots, heartwood, leaves and the aromatic portions (flowers, fruits) of the plant. For example, orange oil is derived from orange peel using various extraction methods. Having similar properties to diesel, essential oils have become promising alternate fuels for diesel engines. The present study explores the opportunity of using sweet orange oil in a compression ignition engine. Blends of sweet orange oil-diesel (10% sweet orange oil, 90% diesel) along with neat diesel fuel were used to operate a six-cylinder diesel engine (5.9 litres, common rail, Euro-III, compression ratio 17.3:1). Some key fuel properties such as: viscosity, density, heating value, and surface tension are presented. Engine performance (brake specific fuel consumption) and emission parameters (CO, NOX, and Particulate Matter) were measured to evaluate running with the blends. The engine was operated at 1500 rpm (maximum torque condition) with different loads. The results from the property analysis showed that sweet orange oil-diesel blend exhibits lower density, viscosity and surface tension and slightly higher calorific value compared to neat diesel fuel. Also, from the engine test, the sweet orange oil-diesel blend exhibited slightly higher brake specific fuel consumption, particulate mass and particulate number; however, the blend reduced the brake specific CO emission slightly and brake specific NOX emission significantly compared to that of neat diesel.

Hybrid biomass-wind power plant for reliable energy generation

International Nuclear Information System (INIS)

Perez-Navarro, A.; Alfonso, D.; Alvarez, C.; Ibanez, F.; Sanchez, C.; Segura, I.

2010-01-01

Massive implementation of renewable energy resources is a key element to reduce CO 2 emissions associated to electricity generation. Wind resources can provide an important alternative to conventional electricity generation mainly based on fossil fuels. However, wind generators are greatly affected by the restrictive operating rules of electricity markets because, as wind is naturally variable, wind generators may have serious difficulties on submitting accurate generation schedules on a day ahead basis, and on complying with scheduled obligations in real-time operation. In this paper, an innovative system combining a biomass gasification power plant, a gas storage system and stand-by generators to stabilize a generic 40 MW wind park is proposed and evaluated with real data. The wind park power production model is based on real data about power production of a Spanish wind park and a probabilistic approach to quantify fluctuations and so, power compensation needs. The hybrid wind-biomass system is analysed to obtain main hybrid system design parameters. This hybrid system can mitigate wind prediction errors and so provide a predictable source of electricity. An entire year cycle of hourly power compensations needs has been simulated deducing storage capacity, extra power needs of the biomass power plant and stand-by generation capacity to assure power compensation during critical peak hours with acceptable reliability. (author)

76 FR 45741 - Approval and Promulgation of Air Quality Implementation Plans; Pennsylvania; Diesel-Powered Motor...

Science.gov (United States)

2011-08-01

... Promulgation of Air Quality Implementation Plans; Pennsylvania; Diesel-Powered Motor Vehicle Idling Act AGENCY... the Commonwealth's Diesel-Powered Motor Vehicle Idling Act (Act 124 of 2008, or simply Act 124) into... allowable time that heavy-duty, commercial highway diesel vehicles of over 10,000 pounds gross vehicle...

Improving compressed air system performance: A sourcebook for industry

OpenAIRE

Mckane, Aimee T.

2003-01-01

Compressed air is used widely throughout industry and is often considered the "fourth utility" at many facilities. Almost every industrial plant, from a small machine shop to an immense pulp and paper mill, has some type of compressed air system. In many cases, the compressed air system is so vital that the facility cannot operate without it. Plant air compressor systems can vary in size from a small unit of 5 horsepower (hp) to huge systems with more than 50,000 hp. In many industrial facili...

Health and efficiency in trimix versus air breathing in compressed air workers.

Science.gov (United States)

Van Rees Vellinga, T P; Verhoeven, A C; Van Dijk, F J H; Sterk, W

2006-01-01

The Western Scheldt Tunneling Project in the Netherlands provided a unique opportunity to evaluate the effects of trimix usage on the health of compressed air workers and the efficiency of the project. Data analysis addressed 318 exposures to compressed air at 3.9-4.4 bar gauge and 52 exposures to trimix (25% oxygen, 25% helium, and 50% nitrogen) at 4.6-4.8 bar gauge. Results revealed three incidents of decompression sickness all of which involved the use of compressed air. During exposure to compressed air, the effects of nitrogen narcosis were manifested in operational errors and increased fatigue among the workers. When using trimix, less effort was required for breathing, and mandatory decompression times for stays of a specific duration and maximum depth were considerably shorter. We conclude that it might be rational--for both medical and operational reasons--to use breathing gases with lower nitrogen fractions (e.g., trimix) for deep-caisson work at pressures exceeding 3 bar gauge, although definitive studies are needed.

Comportamento de um motor de ignição por compressão trabalhando com óleo Diesel e gás natural A dual fuel compression ignition engine performance, running with Diesel fuel and natural gas

Directory of Open Access Journals (Sweden)

José F. Schlosser

2004-12-01

Full Text Available A previsível escassez de petróleo aliada a uma consciência ecológica está levando pesquisadores a procurar novas fontes de energia e processos de combustão mais eficientes e menos poluentes. Entre os combustíveis menos poluentes está o gás natural, cujo consumo aumenta ano a ano. Os motores de combustão interna são transformadores de energia que têm baixa eficiência de conversão. Este trabalho avaliou um motor Diesel, bicombustível, movido a Diesel e gás natural. Nesse motor, a energia provém, basicamente, da combustão do gás natural. O Diesel tem a função de produzir o início da combustão do gás, que é o combustível principal. Assim, haverá uma substituição parcial de óleo Diesel por gás natural, aumentando o rendimento da combustão. Inicialmente, foi feito um ensaio-testemunha, somente com óleo Diesel e após foram feitos ensaios, com três repetições, para variadas proporções de óleo Diesel, gás natural e ângulos de avanço da injeção. O melhor desempenho foi obtido para 22% de óleo Diesel em relação ao máximo débito da bomba injetora e 13 L min-1 de gás natural com ângulo de avanço de injeção original (21º. Nesse caso, a potência média aumentou 14%, e o consumo específico (medido em valores monetários diminuiu 46% em relação ao ensaio-testemunha.The foresight of a petroleum shortage and an ecological conscience is moving scientists to look for new sources of energy and to develop more efficient combustion processes and reduced emissions. Natural gas is a reduced emission fuel, whose consumption increases every year. The present work evaluates a dual fuel compression ignition engine. The major portion of the fuel burned is natural gas. The Diesel fuel acts as combustion starter, which ignites under the compression heat. Diesel fuel is used only as an ignition source. The partial substitution of Diesel fuel by natural gas increases the combustion efficiency and achieves significant

Estimation of CO2 reduction by parallel hard-type power hybridization for gasoline and diesel vehicles.

Science.gov (United States)

Oh, Yunjung; Park, Junhong; Lee, Jong Tae; Seo, Jigu; Park, Sungwook

2017-10-01

The purpose of this study is to investigate possible improvements in ICEVs by implementing fuzzy logic-based parallel hard-type power hybrid systems. Two types of conventional ICEVs (gasoline and diesel) and two types of HEVs (gasoline-electric, diesel electric) were generated using vehicle and powertrain simulation tools and a Matlab-Simulink application programming interface. For gasoline and gasoline-electric HEV vehicles, the prediction accuracy for four types of LDV models was validated by conducting comparative analysis with the chassis dynamometer and OBD test data. The predicted results show strong correlation with the test data. The operating points of internal combustion engines and electric motors are well controlled in the high efficiency region and battery SOC was well controlled within ±1.6%. However, for diesel vehicles, we generated virtual diesel-electric HEV vehicle because there is no available vehicles with similar engine and vehicle specifications with ICE vehicle. Using a fuzzy logic-based parallel hybrid system in conventional ICEVs demonstrated that HEVs showed superior performance in terms of fuel consumption and CO 2 emission in most driving modes. Copyright © 2017 Elsevier B.V. All rights reserved.

Adiabatic Liquid Piston Compressed Air Energy Storage

DEFF Research Database (Denmark)

Petersen, Tage; Elmegaard, Brian; Pedersen, Allan Schrøder

the system. The compression leads to a significant increase in temperature, and the heat generated is dumped into the ambient. This energy loss results in a low efficiency of the system, and when expanding the air, the expansion leads to a temperature drop reducing the mechanical output of the expansion......), but no such units are in operation at present. The CAES system investigated in this project uses a different approach to avoid compression heat loss. The system uses a pre-compressed pressure vessel full of air. A liquid is pumped into the bottom of the vessel when charging and the same liquid is withdrawn through......-CAES system is significantly higher than existing CAES systems due to a low or nearly absent compression heat loss. Furthermore, pumps/turbines, which use a liquid as a medium, are more efficient than air/gas compressors/turbines. In addition, the demand for fuel during expansion does not occur. •The energy...

Design of a Reliable Hybrid (PV/Diesel Power System with Energy Storage in Batteries for Remote Residential Home

Directory of Open Access Journals (Sweden)

Vincent Anayochukwu Ani

2016-01-01

Full Text Available This paper reports the experience acquired with a photovoltaic (PV hybrid system simulated as an alternative to diesel system for a residential home located in Southern Nigeria. The hybrid system was designed to overcome the problem of climate change, to ensure a reliable supply without interruption, and to improve the overall system efficiency (by the integration of the battery bank. The system design philosophy was to maximize simplicity; hence, the system was sized using conventional simulation tool and representative insolation data. The system includes a 15 kW PV array, 21.6 kWh (3600 Ah worth of battery storage, and a 5.4 kW (6.8 kVA generator. The paper features a detailed analysis of the energy flows through the system and quantifies all losses caused by PV charge controller, battery storage round-trip, rectifier, and inverter conversions. In addition, simulation was run to compare PV/diesel/battery with diesel/battery and the results show that the capital cost of a PV/diesel hybrid solution with batteries is nearly three times higher than that of a generator and battery combination, but the net present cost, representing cost over the lifetime of the system, is less than one-half of the generator and battery combination.

Dimethyl Ether in Diesel Fuel Injection Systems

DEFF Research Database (Denmark)

Sorenson, Spencer C.; Glensvig, M.; Abata, D. L.

1998-01-01

A study of the behaviour of DME in diesel injection systems. A discussion of the effects of compressibility of DME on compression work and wave propagation.DME spray shapes and penetration rates......A study of the behaviour of DME in diesel injection systems. A discussion of the effects of compressibility of DME on compression work and wave propagation.DME spray shapes and penetration rates...

Compressed air system audit in a chemical company

Energy Technology Data Exchange (ETDEWEB)

Radgen, P. [Fraunhofer ISI, Karlsruhe (Germany)

2005-07-01

This paper describes the results achieved during a compressed air system audit at a chemical company in Switzerland. The aim of the audit conducted in Muttenz at the site of Clariant Schweiz AG was to analyse the installed compressed air system and its operation in order to identify energy and cost saving potentials. Because there was measurement equipment already installed, it was not necessary to install a new meter. Instead the existing data had to be extracted from the controlled system and regrouped for the analysis. Aggregated data for 2003 and 2004 and a set of detailed data acquired in the course of one week were used for the analysis. The audit identified a number of measures to improve the compressed air system, but had to conclude that the saving potentials at this site are below average. The audit included the compressors, the air treatment and air distribution up to production or storage buildings. The saving potential identified was quantified as about 300 000 kWh/a, or 13.3% of the compressed air energy demand. The cost savings were calculated to be around 41 852 Swiss Franks. (orig.)

Efficiency at Sorting Cards in Compressed Air

Science.gov (United States)

Poulton, E. C.; Catton, M. J.; Carpenter, A.

1964-01-01

At a site where compressed air was being used in the construction of a tunnel, 34 men sorted cards twice, once at normal atmospheric pressure and once at 3½, 2½, or 2 atmospheres absolute pressure. An additional six men sorted cards twice at normal atmospheric pressure. When the task was carried out for the first time, all the groups of men performing at raised pressure were found to yield a reliably greater proportion of very slow responses than the group of men performing at normal pressure. There was reliably more variability in timing at 3½ and 2½ atmospheres absolute than at normal pressure. At 3½ atmospheres absolute the average performance was also reliably slower. When the task was carried out for the second time, exposure to 3½ atmospheres absolute pressure had no reliable effect. Thus compressed air affected performance only while the task was being learnt; it had little effect after practice. No reliable differences were found related to age, to length of experience in compressed air, or to the duration of the exposure to compressed air, which was never less than 10 minutes at 3½ atmospheres absolute pressure. PMID:14180485

The system design and performance test of hybrid vertical axis wind turbine

Science.gov (United States)

Dwiyantoro, Bambang Arip; Suphandani, Vivien

2017-04-01

Vertical axis wind turbine is a tool that is being developed to generate energy from wind. One cause is still little use of wind energy is the design of wind turbines that are less precise. Therefore in this study will be developed the system design of hybrid vertical axis wind turbine and tested performance with experimental methods. The design of hybrid turbine based on a straight bladed Darrieus turbine along with a double step Savonius turbine. The method used to design wind turbines is by studying literature, analyzing the critical parts of a wind turbine and the structure of the optimal design. Wind turbine prototype of the optimal design characteristic tests in the wind tunnel experimentally by varying the speed of the wind. From the experimental results show that the greater the wind speed, the greater the wind turbine rotation and torque is raised. The hybrid vertical axis wind turbine has much better self-starting and better conversion efficiency.

An insight on advantage of hybrid sun–wind-tracking over sun-tracking PV system

International Nuclear Information System (INIS)

Rahimi, Masoud; Banybayat, Meisam; Tagheie, Yaghoub; Valeh-e-Sheyda, Peyvand

2015-01-01

Graphical abstract: Real photograph of hybrid sun–wind-tracking system. - Highlights: • Novel hybrid sun–wind-tracking system proposed to enhance PV cell performance. • The wind tracker can cool down the PV cell as sun-tracking system work. • The hybrid tracker achieved 7.4% increase in energy gain over the sun tracker. • The overall daily output energy gain was increased by 49.83% by using this system. - Abstract: This paper introduces the design and application of a novel hybrid sun–wind-tracking system. This hybrid system employs cooling effect of wind, besides the advantages of tracking sun for enhancing power output from examined hybrid photovoltaic cell. The principal experiment focuses on comparison between dual-axes sun-tracking and hybrid sun–wind-tracking photovoltaic (PV) panels. The deductions based on the research tests confirm that the overall daily output energy gain was increased by 49.83% compared with that of a fixed system. Moreover, an overall increase of about 7.4% in the output power was found for the hybrid sun–wind-tracking over the two-axis sun tracking system.

Emissions from Medium-Duty Conventional and Diesel-Electric Hybrid Vehicles; NREL (National Renewable Energy Laboratory)

Energy Technology Data Exchange (ETDEWEB)

Ragatz, A.; Duran, A.; Thornton, M.; Walkowicz, K.

2014-04-02

This presentation discusses the results of emissions testing for medium-duty conventional and diesel-electric hybrid vehicles. Testing was based on a field evaluation approach that utilized the Fleet DNA drive cycle database and NREL’s Renewable Fuels and Lubricants (ReFUEL) Laboratory chassis dynamometer. Vehicles tested included parcel delivery (Class 6 step vans), beverage delivery (Class 8 tractors), and parcel delivery (Class 7 box trucks) vehicles, all with intended service class medium/heavy heavy-duty diesel (MHDD).
Results for fuel economy and tailpipe NOx emissions included: diesel hybrid electric vehicles showed an average fuel economy advantage on identified test cycles: Class 6 Step Vans: 26%; Class 7 Box Trucks: 24.7%; Class 8 Tractors: 17.3%. Vehicle miles traveled is an important factor in determining total petroleum and CO2 displacement. Higher NOx emissions were observed over some test cycles: highly drive cycle dependent; engine-out differences may result from different engine operating point; and selective catalyst reduction temperature may play a role, but does not explain the whole story.

Health and efficiency in trimix versus air breathing in compressed air workers

NARCIS (Netherlands)

van Rees Vellinga, T. P.; Verhoeven, A. C.; van Dijk, F. J. H.; Sterk, W.

2006-01-01

The Western Scheldt Tunneling Project in the Netherlands provided a unique opportunity to evaluate the effects of trimix usage on the health of compressed air workers and the efficiency of the project. Data analysis addressed 318 exposures to compressed air at 3.9-4.4 bar gauge and 52 exposures to

Working characteristics of variable intake valve in compressed air engine.

Science.gov (United States)

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

Probabilistic Wind Power Forecasting with Hybrid Artificial Neural Networks

DEFF Research Database (Denmark)

Wan, Can; Song, Yonghua; Xu, Zhao

2016-01-01

probabilities of prediction errors provide an alternative yet effective solution. This article proposes a hybrid artificial neural network approach to generate prediction intervals of wind power. An extreme learning machine is applied to conduct point prediction of wind power and estimate model uncertainties...... via a bootstrap technique. Subsequently, the maximum likelihood estimation method is employed to construct a distinct neural network to estimate the noise variance of forecasting results. The proposed approach has been tested on multi-step forecasting of high-resolution (10-min) wind power using...... actual wind power data from Denmark. The numerical results demonstrate that the proposed hybrid artificial neural network approach is effective and efficient for probabilistic forecasting of wind power and has high potential in practical applications....

Hybrid system power generation'wind-photovoltaic' connected to the ...

African Journals Online (AJOL)

Hybrid system power generation'wind-photovoltaic' connected to the ... from Hybrid System, power delivered to or from grid and phase voltage of the inverter leg. ... Renewable Energy, Electrical Network 220 kV, Hybrid System, Solar, MPPT.

Total Particle Number Emissions from Modern Diesel, Natural Gas, and Hybrid Heavy-Duty Vehicles During On-Road Operation.

Science.gov (United States)

Wang, Tianyang; Quiros, David C; Thiruvengadam, Arvind; Pradhan, Saroj; Hu, Shaohua; Huai, Tao; Lee, Eon S; Zhu, Yifang

2017-06-20

Particle emissions from heavy-duty vehicles (HDVs) have significant environmental and public health impacts. This study measured total particle number emission factors (PNEFs) from six newly certified HDVs powered by diesel and compressed natural gas totaling over 6800 miles of on-road operation in California. Distance-, fuel- and work-based PNEFs were calculated for each vehicle. Distance-based PNEFs of vehicles equipped with original equipment manufacturer (OEM) diesel particulate filters (DPFs) in this study have decreased by 355-3200 times compared to a previous retrofit DPF dynamometer study. Fuel-based PNEFs were consistent with previous studies measuring plume exhaust in the ambient air. Meanwhile, on-road PNEF shows route and technology dependence. For vehicles with OEM DPFs and Selective Catalytic Reduction Systems, PNEFs under highway driving (i.e., 3.34 × 10 12 to 2.29 × 10 13 particles/mile) were larger than those measured on urban and drayage routes (i.e., 5.06 × 10 11 to 1.31 × 10 13 particles/mile). This is likely because a significant amount of nucleation mode volatile particles were formed when the DPF outlet temperature reached a critical value, usually over 310 °C, which was commonly achieved when vehicle speed sustained over 45 mph. A model year 2013 diesel HDV produced approximately 10 times higher PNEFs during DPF active regeneration events than nonactive regeneration.

Economics of a small wind pump system based on estimated petrol and diesel cost savings from use in Northern Nigeria

Directory of Open Access Journals (Sweden)

C. J. Ejieji

2013-08-01

Full Text Available Eleven years of daily wind records were analyzed for the estimation of available wind energy for water pumping at three selected locations in Northern Nigeria, namely Jos, Kano and Sokoto. This formed the basis for investigating the economics of the use of an imported small wind pump under a deregulated energy market environment. The estimated available energy for water pumping at the installation height of 9m was 190 kwh/m2/yr for Jos, 225 kwh/m2/yr for Kano and 348 kwh/m2/yr for Sokoto. The monetary value of the available wind energy was considered as saved energy cost. The saved cost was obtained in terms of the unsubsidized cost of the petrol and diesel that an internal combustion engine (ICE would consume to produce energy equivalent to the available wind energy. At the prevailing interest and inflation rates of 21.96 % and 12.1% respectively, and unsubsidized prices of N 131.32/l and N 140.23/l for petrol and diesel respectively, investment in the wind pump was not found to be economically competitive relative to using a pump with ICE prime mover at the three locations unless the cost of the pump was subsidized. For Sokoto, the estimated subsidy for initial cost of the wind pump required for the investment to be competitive relative to the use of a pump driven by a petrol ICE was 16%. Relative to a pump driven by a diesel ICE, the required subsidy was 24%. The corresponding subsidy estimates for Kano were 48 % and 51 % respectively. For Jos, it was 56% relative to the use of a pump driven by a petrol ICE and 60 % relative to that driven by a diesel ICE. Considering the potential environmental and social and environmental benefits however, subsidy support by government for local manufacturing of the pumps was recommended since shipping cost and custom tariff constituted over 36% of the initial cost of the wind pump.

Statistics-Based Compression of Global Wind Fields

KAUST Repository

Jeong, Jaehong

2017-02-07

Wind has the potential to make a significant contribution to future energy resources. Locating the sources of this renewable energy on a global scale is however extremely challenging, given the difficulty to store very large data sets generated by modern computer models. We propose a statistical model that aims at reproducing the data-generating mechanism of an ensemble of runs via a Stochastic Generator (SG) of global annual wind data. We introduce an evolutionary spectrum approach with spatially varying parameters based on large-scale geographical descriptors such as altitude to better account for different regimes across the Earth\\'s orography. We consider a multi-step conditional likelihood approach to estimate the parameters that explicitly accounts for nonstationary features while also balancing memory storage and distributed computation. We apply the proposed model to more than 18 million points of yearly global wind speed. The proposed SG requires orders of magnitude less storage for generating surrogate ensemble members from wind than does creating additional wind fields from the climate model, even if an effective lossy data compression algorithm is applied to the simulation output.

Statistics-Based Compression of Global Wind Fields

KAUST Repository

Jeong, Jaehong; Castruccio, Stefano; Crippa, Paola; Genton, Marc G.

2017-01-01

Wind has the potential to make a significant contribution to future energy resources. Locating the sources of this renewable energy on a global scale is however extremely challenging, given the difficulty to store very large data sets generated by modern computer models. We propose a statistical model that aims at reproducing the data-generating mechanism of an ensemble of runs via a Stochastic Generator (SG) of global annual wind data. We introduce an evolutionary spectrum approach with spatially varying parameters based on large-scale geographical descriptors such as altitude to better account for different regimes across the Earth's orography. We consider a multi-step conditional likelihood approach to estimate the parameters that explicitly accounts for nonstationary features while also balancing memory storage and distributed computation. We apply the proposed model to more than 18 million points of yearly global wind speed. The proposed SG requires orders of magnitude less storage for generating surrogate ensemble members from wind than does creating additional wind fields from the climate model, even if an effective lossy data compression algorithm is applied to the simulation output.

Performance of a hydraulic air compressor for use in compressed air energy storage power systems

Energy Technology Data Exchange (ETDEWEB)

Berghmans, J. A.; Ahrens, F. W.

1978-01-01

A fluid mechanical analysis of a hydraulic air compression system for Compressed Air Energy Storage (CAES) application is presented. With this compression concept, air is charged into an underground reservoir, for later use in power generation, by entraining bubbles into a downward flow of water from a surface reservoir. Upon releasing the air in the underground reservoir, the water is pumped back to the surface. The analytical model delineated is used to predict the hydraulic compressor performance characteristics (pumping power, pump head, compression efficiency) as a function of water flow rate and system geometrical parameters. The results indicate that, although large water pumps are needed, efficiencies as high as 90% (relative to ideal isothermal compression) can be expected. This should result in lower compression power than for conventional compressor systems, while eliminating the need for the usual intercoolers and aftercooler.

PV-wind hybrid system performance. A new approach and a case study

International Nuclear Information System (INIS)

Arribas, Luis; Cano, Luis; Cruz, Ignacio; Mata, Montserrat; Llobet, Ermen

2010-01-01

Until now, there is no internationally accepted guideline for the measurement, data exchange and analysis of PV-Wind Hybrid Systems. As there is a need for such a tool, so as to overcome the barrier that the lack of confidence due to the absence of reliability means for the development of the market of Hybrid Systems, an effort has been made to suggest one tool for PV-Wind Hybrid Systems. The suggested guidelines presented in this work are based on the existing guidelines for PV Systems, as a PV-Wind Hybrid system can be roughly thought of as a PV System to which wind generation has been added. So, the guidelines for PV Systems are valid for the PV-Wind System, and only the part referred to wind generation should be included. This has been the process followed in this work. The proposed method is applied to a case study, the CICLOPS Project, a 5 kW PV, 7.5 kW Wind Hybrid system installed at the Isolated Wind Systems Test Site that CIEMAT owns in CEDER (Soria, Spain). This system has been fully monitored through a year and the results of the monitoring activity, characterizing the long-term performance of the system are shown in this work. (author)

PV-wind hybrid system performance. A new approach and a case study

Energy Technology Data Exchange (ETDEWEB)

Arribas, Luis; Cano, Luis; Cruz, Ignacio [Departamento de Energias Renovables, CIEMAT, Avda. Complutense 22, 28040 Madrid (Spain); Mata, Montserrat; Llobet, Ermen [Ecotecnia, Roc Boronat 78, 08005 Barcelona (Spain)

2010-01-15

Until now, there is no internationally accepted guideline for the measurement, data exchange and analysis of PV-Wind Hybrid Systems. As there is a need for such a tool, so as to overcome the barrier that the lack of confidence due to the absence of reliability means for the development of the market of Hybrid Systems, an effort has been made to suggest one tool for PV-Wind Hybrid Systems. The suggested guidelines presented in this work are based on the existing guidelines for PV Systems, as a PV-Wind Hybrid system can be roughly thought of as a PV System to which wind generation has been added. So, the guidelines for PV Systems are valid for the PV-Wind System, and only the part referred to wind generation should be included. This has been the process followed in this work. The proposed method is applied to a case study, the CICLOPS Project, a 5 kW PV, 7.5 kW Wind Hybrid system installed at the Isolated Wind Systems Test Site that CIEMAT owns in CEDER (Soria, Spain). This system has been fully monitored through a year and the results of the monitoring activity, characterizing the long-term performance of the system are shown in this work. (author)

Working Characteristics of Variable Intake Valve in Compressed Air Engine

Science.gov (United States)

Yu, Qihui; Shi, Yan; Cai, Maolin

2014-01-01

A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine. PMID:25379536

Working Characteristics of Variable Intake Valve in Compressed Air Engine

Directory of Open Access Journals (Sweden)

Qihui Yu

2014-01-01

Full Text Available A new camless compressed air engine is proposed, which can make the compressed air energy reasonably distributed. Through analysis of the camless compressed air engine, a mathematical model of the working processes was set up. Using the software MATLAB/Simulink for simulation, the pressure, temperature, and air mass of the cylinder were obtained. In order to verify the accuracy of the mathematical model, the experiments were conducted. Moreover, performance analysis was introduced to design compressed air engine. Results show that, firstly, the simulation results have good consistency with the experimental results. Secondly, under different intake pressures, the highest output power is obtained when the crank speed reaches 500 rpm, which also provides the maximum output torque. Finally, higher energy utilization efficiency can be obtained at the lower speed, intake pressure, and valve duration angle. This research can refer to the design of the camless valve of compressed air engine.

Mathematical modeling of compression processes in air-driven boosters

International Nuclear Information System (INIS)

Li Zeyu; Zhao Yuanyang; Li Liansheng; Shu Pengcheng

2007-01-01

The compressed air in normal pressure is used as the source of power of the air-driven booster. The continuous working of air-driven boosters relies on the difference of surface area between driven piston and driving piston, i.e., the different forces acting on the pistons. When the working surface area of the driving piston for providing power is greater than that of the driven piston for compressing gas, the gas in compression chamber will be compressed. On the basis of the first law of thermodynamics, the motion regulation of piston is analyzed and the mathematical model of compression processes is set up. Giving a calculating example, the vary trends of gas pressure and pistons' move in working process of booster have been gotten. The change of parameters at different working conditions is also calculated and compared. And the corresponding results can be referred in the design of air-driven boosters

Experimental investigations of the hydrogen addition effects on diesel engine performance

Science.gov (United States)

Mirica, I.; Pana, C.; Negurescu, N.; Cernat, A.; Nutu, C.

2016-08-01

In the global content regarding the impact on the environmental of the gases emissions resulted from the fossil fuels combustion, an interest aspect discussed on the 21st Session of the Conference of the Parties from the 2015 Paris Climate Conference and the gradual diminution of the worldwide oil reserves contribute to the necessity of searching of alternative energy from durable and renewable resources. At the use of hydrogen as addition in air to diesel engine, the level of CO, HC and smoke from the exhaust gases will decrease due to the improvement of the combustion process. At low and medium partial loads and low hydrogen energetic ratios used the NOX emission level can decrease comparative to classic diesel engine. The hydrogen use as fuel for diesel engine leads to the improving of the energetic and emissions performance of the engine due to combustion improvement and reduction of carbon content. The paper presents, in a comparative way, results of the experimental researches carried on a truck compression ignition engine fuelled with diesel fuel and with hydrogen diesel fuel and hydrogen as addition in air at different engine operation regimes. The results obtained during experimental investigations show better energetic and pollution performance of the engine fuelled with hydrogen as addition in air comparative to classic engine. The influences of hydrogen addition on engine operation are shown.

Electrical Energy Forecasting and Optimal Allocation of ESS in a Hybrid Wind-Diesel Power System

Directory of Open Access Journals (Sweden)

Hai Lan

2017-02-01

Full Text Available Due to the increasingly serious energy crisis and environmental pollution problem, traditional fossil energy is gradually being replaced by renewable energy in recent years. However, the introduction of renewable energy into power systems will lead to large voltage fluctuations and high capital costs. To solve these problems, an energy storage system (ESS is employed into a power system to reduce total costs and greenhouse gas emissions. Hence, this paper proposes a two-stage method based on a back-propagation neural network (BPNN and hybrid multi-objective particle swarm optimization (HMOPSO to determine the optimal placements and sizes of ESSs in a transmission system. Owing to the uncertainties of renewable energy, a BPNN is utilized to forecast the outputs of the wind power and load demand based on historic data in the city of Madison, USA. Furthermore, power-voltage (P-V sensitivity analysis is conducted in this paper to improve the converge speed of the proposed algorithm, and continuous wind distribution is discretized by a three-point estimation method. The Institute of Electrical and Electronic Engineers (IEEE 30-bus system is adopted to perform case studies. The simulation results of each case clearly demonstrate the necessity for optimal storage allocation and the efficiency of the proposed method.

Energy storage technologies and hybrid architectures for specific diesel-driven rail duty cycles: Design and system integration aspects

International Nuclear Information System (INIS)

Meinert, M.; Prenleloup, P.; Schmid, S.; Palacin, R.

2015-01-01

Highlights: • We assessed integration of energy storage systems into hybrid system architectures. • We considered mechanical and electrical energy storage systems. • Potential of different combinations has been analyzed by standardized duty cycles. • Most promising are diesel-driven suburban, regional and shunting operations. • Double-layer capacitors and Lithium-ion batteries have the highest potential. - Abstract: The use of diesel-driven traction is an intrinsic part of the functioning of railway systems and it is expected to continue being so for the foreseeable future. The recent introduction of more restrictive greenhouse gas emission levels and other legislation aiming at the improvement of the environmental performance of railway systems has led to the need of exploring alternatives for cleaner diesel rolling stock. This paper focuses on assessing energy storage systems and the design of hybrid system architectures to determine their potential use in specific diesel-driven rail duty cycles. Hydrostatic accumulators, flywheels, Lithium-ion batteries and double-layer capacitors have been assessed and used to design hybrid system architectures. The potential of the different technology combinations has been analyzed using standardized duty cycles enhanced with gradient profiles related to suburban, regional and shunting operations. The results show that double-layer capacitors and Lithium-ion batteries have the highest potential to be successfully integrated into the system architecture of diesel-driven rail vehicles. Furthermore, the results also suggest that combining these two energy storage technologies into a single hybridisation package is a highly promising design that draws on their strengthens without any significant drawbacks.

Establishment of Combustion Model for Isooctane HCCI Marine Diesel Engine and Research on the Combustion Characteristic

Directory of Open Access Journals (Sweden)

Li Biao

2016-01-01

Full Text Available The homogeneous charge compression ignition (HCCI combustion mode applied in marine diesel engine is expected to be one of alternative technologies to decrease nitrogen oxide (NOX emission and improve energy utilization rate. Applying the chemical-looping combustion (CLC mechanism inside the cylinder, a numerical study on the HCCI combustion process is performed taking a marine diesel engine as application object. The characteristic feature of combustion process is displayed. On this basis, the formation and emission of NOX are analyzed and discussed. The results indicate that the HCCI combustion mode always exhibit two combustion releasing heats: low-temperature reaction and high-temperature reaction. The combustion phase is divided into low-temperature reaction zone, high-temperature reaction zone and negative temperature coefficient (NTC zone. The operating conditions of the high compression ratio, high intake air temperature, low inlet pressure and small excess air coefficient would cause the high in-cylinder pressure which often leads engine detonation. The low compression ratio, low intake air temperature and big excess air coefficient would cause the low combustor temperature which is conducive to reduce NOX emissions. These technological means and operating conditions are expected to meet the NOX emissions limits in MARPOL73/78 Convention-Annex VI Amendment.

Canadian Wind Energy Association small wind conference proceedings : small wind policy developments (turbines of 300 kW or less)

International Nuclear Information System (INIS)

2005-01-01

The small wind session at the Canadian Wind Energy Association's (CanWEA) annual conference addressed policies affecting small wind, such as net metering, advanced renewable tariffs and interconnections. It also addressed CanWEA's efforts in promoting small wind turbines, particularly in remote northern communities, small businesses and within the residential sector. Small wind systems are typically installed in remote communities to offset utility supplied electricity at the retail price level. In certain circumstances, small wind and hybrid systems can produce electricity at less than half the cost of traditional electricity sources, which in remote communities is typically diesel generators. Small wind turbines require different materials and technologies than large wind turbines. They also involve different local installation requirements, different by-laws, tax treatment and environmental assessments. Small wind turbines are typically installed for a range of factors, including energy independence, energy price stability and to lower environmental impacts of traditional power generation. The small wind session at the conference featured 14 presentations, of which 4 have been catalogued separately for inclusion in this database. tabs., figs

A cost-effective compressed air generation for manufacturing using modified microturbines

International Nuclear Information System (INIS)

Eret, Petr

2016-01-01

Highlights: • A new cost-effective way of compressed air generation for manufacturing in SME is proposed. • The approach is based on a modified microturbine configuration. • Thermodynamic and life cycle analyses are presented and economic benefit is demonstrated. - Abstract: Compressed air is an irreplaceable energy source for some manufacturing processes, and is also common in applications even when there are alternatives. As a result, compressed air is a key utility in manufacturing industry, but unfortunately the cost of compressed air production is one of the most expensive processes in a manufacturing facility. In order to reduce the compressed air generation cost an unconventional way using a microturbine configuration is proposed. The concept is based on an extraction of a certain amount of compressed air from/after the compressor with the residual air flowing to the turbine to produce sufficient back power to drive the compressor. A thermodynamic and life cycle analysis are presented for several system variations, including a simple cycle without a recuperator and a complex configuration with an intercooler, recuperator and reheating. The study is based on the typical requirements (i.e. quantity, pressure) for a small to medium sized industrial compressed air system. The analysis is focused on the North American market due to the low price of natural gas. The lowest life cycle cost alternative is represented by a microturbine concept with a recuperator, air extraction after partial compression, intercooler and aftercooler. A comparison of an electric motor and conventional microturbine prime movers demonstrates the economic benefit of the proposed compressed air generation method, for the design parameters and utility prices considered.

Hybrid wind–photovoltaic–diesel–battery system sizing tool development using empirical approach, life-cycle cost and performance analysis: A case study in Scotland

International Nuclear Information System (INIS)

Gan, Leong Kit; Shek, Jonathan K.H.; Mueller, Markus A.

2015-01-01

Highlights: • Methods of sizing a hybrid wind–photovoltaic–diesel–battery system is described. • The hybrid system components are modelled using empirical data. • Twenty years lifecycle cost of the hybrid system is considered. • The trade-offs between battery storage capacity and diesel fuel usage is studied. • A hybrid system sizing tool has been developed as a graphical user interface (GUI). - Abstract: The concept of off-grid hybrid wind energy system is financially attractive and more reliable than stand-alone power systems since it is based on more than one electricity generation source. One of the most expensive components in a stand-alone wind-power system is the energy storage system as very often it is oversized to increase system autonomy. In this work, we consider a hybrid system which consists of wind turbines, photovoltaic panels, diesel generator and battery storage. One of the main challenges experienced by project managers is the sizing of components for different sites. This challenge is due to the variability of the renewable energy resource and the load demand for different sites. This paper introduces a sizing model that has been developed and implemented as a graphical user interface, which predicts the optimum configuration of a hybrid system. In particular, this paper focuses on seeking the optimal size of the batteries and the diesel generator usage. Both of these components are seen to be trade-offs from each other. The model simulates real time operation of the hybrid system, using the annual measured hourly wind speed and solar irradiation. The benefit of using time series approach is that it reflects a more realistic situation; here, the peaks and troughs of the renewable energy resource are a central part of the sizing model. Finally, load sensitivity and hybrid system performance analysis are demonstrated.

Evaluation of the wind pumped hydropower storage integrated flood mitigation system

Science.gov (United States)

Safi, Aishah; Basrawi, Firdaus

2018-04-01

As Wind Pumped Hydropower Storage (WPHS) need high cost to construct, it is important to study their impacts on economic and environmental aspects. Thus, this research aims to evaluate their economic and environmental performances. First, Hybrid Optimization Model for Electric Renewable (HOMER) was used to simulate power generation system with and without the flood reservoir. Next, the total amount of emitted air pollutant was used to evaluate the environmental impacts. It was found the wind-diesel with reservoir storage system (A-III) will have much lower NPC than other systems that do not include reservoir for flood mitigation when the cost of flood losses are included in the total Net Present Cost (NPC). The NPC for system A-III was RM 1.52 million and for diesel standalone system (A-I) is RM 10.8 million when the cost of flood losses are included in the total NPC. Between both energy systems, the amount of pollutants emitted by the A-III system was only 408 kg-CO2/year which is much less than the A-I system which is 99, 754 kg of carbon dioxide per year. To conclude, the WPHS integrated with flood mitigation system seems promising in the aspects of economic and environment.

Free-beam soliton self-compression in air

Science.gov (United States)

Voronin, A. A.; Mitrofanov, A. V.; Sidorov-Biryukov, D. A.; Fedotov, A. B.; Pugžlys, A.; Panchenko, V. Ya; Shumakova, V.; Ališauskas, S.; Baltuška, A.; Zheltikov, A. M.

2018-02-01

We identify a physical scenario whereby soliton transients generated in freely propagating laser beams within the regions of anomalous dispersion in air can be compressed as a part of their free-beam spatiotemporal evolution to yield few-cycle mid- and long-wavelength-infrared field waveforms, whose peak power is substantially higher than the peak power of the input pulses. We show that this free-beam soliton self-compression scenario does not require ionization or laser-induced filamentation, enabling high-throughput self-compression of mid- and long-wavelength-infrared laser pulses within a broad range of peak powers from tens of gigawatts up to the terawatt level. We also demonstrate that this method of pulse compression can be extended to long-range propagation, providing self-compression of high-peak-power laser pulses in atmospheric air within propagation ranges as long as hundreds of meters, suggesting new ways towards longer-range standoff detection and remote sensing.

Optimalisasi Desain Sistem Pembangkit Listrik Tenaga Hybrid Diesel Generator  Photovoltaic Array Menggunakan Homer (Studi Kasus : Desa Sirilogui, Kabupaten Kepulauan Mentawai

Directory of Open Access Journals (Sweden)

Dewi Purnama Sari

2015-03-01

Full Text Available Hybrid Power Plant is one of the solutions to overcome the shortage of electricity in underdeveloped and isolated areas not covered by PLN electricity network, due to underdeveloped regions generally have the geography and topography that does not allow for expansion of PLN electricity network. Integration of the two power plants is a conventional power plant (diesel generator that comes from fuel oil (BBM with power plants sourced from renewable energy (photovoltaic arrays is an advantageous solution to meet the needs of daily electricity load in remote areas such as the Village Sirilogui located in the District of North Siberut Mentawai Islands, because the integration of photovoltaic arrays diesel generator can provide 24 hour lighting solution for 310 households (families in the village Sirilogui which at first only enjoy the lighting for 4 hours, and even then only at night days, from 06.00 to 10.00 pm o'clock sourced from 3 units of diesel generator. With the integration of these two power plants, diesel generator operation can be minimized so it saves fuel consumption and reduce CO2 emissions caused by the operation of the diesel generator. This study focuses the discussion on Design Optimization of Hybrid Power Plant System Diesel Generator-Photovoltaic Array by using HOMER as a tool for simulation. HOMER software is used to help simplify the task of the modeler in evaluating the design of hybrid power plant system that allows to sort based on the total net present cost (TNPC, the lowest for the most optimal system. In this study, the results of the design for the system with the daily electricity load of 479,280 kWh most optimal based on the simulation results using HOMER ie photovoltaic capacity of 65 kW, 3 units of diesel generators with a capacity of each 15 kW, 156 units of battery and bidirectional converter with a capacity of 78 kW TNPC amounted to $ 1.362.474 and the cost of energy (COE of $ 1,485/kWh. Hybrid Power Plant System

Impacts of compressed air energy storage plant on an electricity market with a large renewable energy portfolio

International Nuclear Information System (INIS)

Foley, A.; Díaz Lobera, I.

2013-01-01

Renewable energy generation is expected to continue to increase globally due to renewable energy targets and obligations to reduce greenhouse gas emissions. Some renewable energy sources are variable power sources, for example wind, wave and solar. Energy storage technologies can manage the issues associated with variable renewable generation and align non-dispatchable renewable energy generation with load demands. Energy storage technologies can play different roles in each of the step of the electric power supply chain. Moreover, large scale energy storage systems can act as renewable energy integrators by smoothing the variability. Compressed air energy storage is one such technology. This paper examines the impacts of a compressed air energy storage facility in a pool based wholesale electricity market in a power system with a large renewable energy portfolio

Village power hybrid systems development in the United States

Energy Technology Data Exchange (ETDEWEB)

Flowers, L.; Green, J. [National Renewable Energy Lab., Golden, CO (United States); Bergey, M. [Bergey Windpower Co., Norman, OK (United States); Lilley, A. [Westinghouse Electric Corp., Pittsburgh, PA (United States); Mott, L. [Northern Power Systems, Moretown, VT (United States)

1994-11-01

The energy demand in developing countries is growing at a rate seven times that of the OECD countries, even though there are still 2 billion people living in developing countries without electricity. Many developing countries have social and economic development programs aimed at stemming the massive migration from the rural communities to the overcrowded, environmentally problematic, unemployment-bound urban centers. To address the issue of providing social, educational, health, and economic benefits to the rural communities of the developing world, a number of government and nongovernment agencies are sponsoring pilot programs to install and evaluate renewable energy systems as alternatives to line extension, diesels, kerosene, and batteries. The use of renewables in remote villages has yielded mixed results over the last 20 years. However, recently, photovoltaics, small wind turbines, and microhydro system shave gained increasing recognition as reliable, cost-effective alternatives to grid extension and diesel gensets for village-electricity applications. At the same time, hybrid systems based on combinations of PV/wind/batteries/diesel gensets have proven reliable and economic for remote international telecommunications markets. With the growing emphasis on environmentally and economically sustainable development of international rural communities, the US hybrid industry is responding with the development and demonstration of hybrid systems and architectures that will directly compete with conventional alternatives for village electrification. Assisting the US industry in this development, the National Renewable Energy Laboratory (NREL) has embarked on a program of collaborative technology development and technical assistance in the area of hybrid systems for village power. Following a brief review of village-power hybrid systems application and design issues, this paper presents the present industry development activities of three US suppliers and the NREL.

A Novel Constant-Pressure Pumped Hydro Combined with Compressed Air Energy Storage System

Directory of Open Access Journals (Sweden)

Erren Yao

2014-12-01

Full Text Available As intermittent renewable energy is receiving increasing attention, the combination of intermittent renewable energy with large-scale energy storage technology is considered as an important technological approach for the wider application of wind power and solar energy. Pumped hydro combined with compressed air energy storage system (PHCA is one of the energy storage systems that not only integrates the advantages but also overcomes the disadvantages of compressed air energy storage (CAES systems and pumped hydro energy storage systems to solve the problem of energy storage in China’s arid regions. Aiming at the variable working conditions of PHCA system technology, this study proposes a new constant-pressure PHCA. The most significant characteristics of this system were that the water pump and hydroturbine work under stable conditions and this improves the working efficiency of the equipment without incurring an energy loss. In addition, the constant-pressure PHCA system was subjected to energy and exergy analysis, in expectation of exploring an attractive solution for the large-scale storage of existing intermittent renewable energy.

Thermodynamic analysis of a variable compression ratio diesel engine running with palm oil methyl ester

International Nuclear Information System (INIS)

Debnath, Biplab K.; Sahoo, Niranjan; Saha, Ujjwal K.

2013-01-01

Highlights: ► Energy and exergy analysis of palm oil methyl ester (POME) run diesel engine. ► Engine was run at various compression ratios (CRs) and injection timings (ITs). ► POME can recover around 26% of the energy supplied by the fuel. ► CR rise and IT change cause shaft energy per unit fuel supply to increase. ► CR of 18 and IT of 20°BTDC reduce more entropy generation. - Abstract: The present work is set to explore the effect of compression ratio (CR) and injection timing (IT) on energy and exergy potential of a palm oil methyl ester (POME) run diesel engine. Experiments are carried out in a single cylinder, direct injection, water cooled variable compression ratio diesel engine at a constant peed of 1500 rpm under a full load of 4.24 bar brake mean effective pressure (BMEP). The study involves four different CRs of 16, 17, 17.5 and 18; and three different ITs of 20°, 23° and 28°BTDC. Here, the CR of 17.5 and IT of 23°BTDC are the standard ones. The energy analysis performed for the experimental data includes shaft power, energy input through fuel, output by cooling water and exhaust, uncounted loss per unit time. Side by side, the effects of varying CR and IT on peak pressure, peak heat release rate, brake thermal efficiency and exhaust gas temperature are also studied. The exergy analysis is carried out for availability input, shaft, cooling water and exhaust availability, availability destruction and entropy generation. It shows that higher values of CR increase the shaft availability and cooling water availability, however, they decrease the exhaust flow availability. The retardation and advancement of IT give similar results. The exergy analysis also shows that with the increase of CR, the injection retardation and advancement increase the shaft availability and exergy efficiency, while it reduces the exergy destruction. The entropy generation is also reduced for the similar CR and IT modifications.

Study of emissions for a compression ignition engine fueled with a mix of DME and diesel

Science.gov (United States)

Jurchiş, Bogdan; Nicolae, Burnete; Călin, Iclodean; Nicolae Vlad, Burnete

2017-10-01

Currently, there is a growing demand for diesel engines, primarily due to the relatively low fuel consumption compared to spark-ignition engines. However, these engines have a great disadvantage in terms of pollution because they produce solid particles that ultimately form particulate matter (PM), which has harmful effects on human health and also on the environment. The toxic emissions from the diesel engine exhaust, like particulate matter (PM) and NOx, generated by the combustion of fossil fuels, lead to the necessity to develop green fuels which on one hand should be obtained from regenerative resources and on the other hand less polluting. In this paper, the authors focused on the amount of emissions produced by a diesel engine when running with a fuel mixture consisting of diesel and DME. Dimethyl ether (DME) is developed mainly by converting natural gas or biomass to synthesis gas (syngas). It is an extremely attractive resource for the future used in the transport industry, given that it can be obtained at low costs from renewable resources. Using DME mixed with diesel for the combustion process, besides the fact that it produces less smoke, the emission levels of particulate matter is reduced compared to diesel and in some situations, NOx emissions may decrease. DME has a high enough cetane number to perform well as a compression-ignition fuel but due to the poor lubrication and viscosity, it is difficult to be used as the main fuel for combustion

Modelling and experimentation on air hybrid engine concepts for automotive applications

OpenAIRE

Psanis, Christodoulos

2007-01-01

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University. Hybrid powertrains that use compressed air to help power a vehicle could dramatically improve the fuel economy, particularly in cities and urban areas where the traffic conditions involve a lot of starts and stops. In such conditions, a large amount of fuel is needed to accelerate the vehicle, and much of this is converted to heat in brake friction during decelerations. Capturing, storing and...

Sizing wind/photovoltaic hybrids for households in inner Mongolia

Energy Technology Data Exchange (ETDEWEB)

Barley, C.D.; Lew, D.J.; Flowers, L.T. [National Renewable Energy Lab., Golden, CO (United States)

1997-12-31

Approximately 140,000 wind turbines currently provide electricity to about one-third of the non-grid-connected households in Inner Mongolia. However, these households often suffer from a lack of power during the low-wind summer months. This report describes an analysis of hybrid wind/photovoltaic (PV) systems for such households. The sizing of the major components is based on a subjective trade-off between the cost of the system and the percent unmet load, as determined by the Hybrid2 software in conjunction with a simplified time-series model. Actual resource data (wind speed and solar radiation) from the region are processed so as to best represent the scenarios of interest. Small wind turbines of both Chinese and U.S. manufacture are considered in the designs. The results indicate that combinations of wind and PV are more cost-effective than either one alone, and that the relative amount of PV in the design increases as the acceptable unmet load decreases and as the average wind speed decreases.

Development of intelligent MPPT (maximum power point tracking) control for a grid-connected hybrid power generation system

International Nuclear Information System (INIS)

Hong, Chih-Ming; Ou, Ting-Chia; Lu, Kai-Hung

2013-01-01

A hybrid power control system is proposed in the paper, consisting of solar power, wind power, and a diesel-engine. To achieve a fast and stable response for the real power control, an intelligent controller was proposed, which consists of the Wilcoxon (radial basis function network) RBFN and the improved (Elman neural network) ENN for (maximum power point tracking) MPPT. The pitch angle control of wind power uses improved ENN controller, and the output is fed to the wind turbine to achieve the MPPT. The solar array is integrated with an RBFN control algorithm to track the maximum power. MATLAB (MATrix LABoratory)/Simulink was used to build the dynamic model and simulate the solar and diesel-wind hybrid power system. - Highlights: ► To achieve a fast and stable response for the real power control. ► The pitch control of wind power uses improved ENN (Elman neural network) controller to achieve the MPPT (maximum power point tracking). ► The RBFN (radial basis function network) can quickly and accurately track the maximum power output for PV (photovoltaic) array. ► MATLAB was used to build the dynamic model and simulate the hybrid power system. ► This method can reach the desired performance even under different load conditions

Hybrid Optimization for Wind Turbine Thick Airfoils

Energy Technology Data Exchange (ETDEWEB)

Grasso, F. [ECN Wind Energy, Petten (Netherlands)

2012-06-15

One important element in aerodynamic design of wind turbines is the use of specially tailored airfoils to increase the ratio of energy capture and reduce cost of energy. This work is focused on the design of thick airfoils for wind turbines by using numerical optimization. A hybrid scheme is proposed in which genetic and gradient based algorithms are combined together to improve the accuracy and the reliability of the design. Firstly, the requirements and the constraints for this class of airfoils are described; then, the hybrid approach is presented. The final part of this work is dedicated to illustrate a numerical example regarding the design of a new thick airfoil. The results are discussed and compared to existing airfoils.

Analysis of the solar/wind resources in Southern Spain for optimal sizing of hybrid solar-wind power generation systems

Science.gov (United States)

Quesada-Ruiz, S.; Pozo-Vazquez, D.; Santos-Alamillos, F. J.; Lara-Fanego, V.; Ruiz-Arias, J. A.; Tovar-Pescador, J.

2010-09-01

A drawback common to the solar and wind energy systems is their unpredictable nature and dependence on weather and climate on a wide range of time scales. In addition, the variation of the energy output may not match with the time distribution of the load demand. This can partially be solved by the use of batteries for energy storage in stand-alone systems. The problem caused by the variable nature of the solar and wind resources can be partially overcome by the use of energy systems that uses both renewable resources in a combined manner, that is, hybrid wind-solar systems. Since both resources can show complementary characteristics in certain location, the independent use of solar or wind systems results in considerable over sizing of the batteries system compared to the use of hybrid solar-wind systems. Nevertheless, to the day, there is no single recognized method for properly sizing these hybrid wind-solar systems. In this work, we present a method for sizing wind-solar hybrid systems in southern Spain. The method is based on the analysis of the wind and solar resources on daily scale, particularly, its temporal complementary characteristics. The method aims to minimize the size of the energy storage systems, trying to provide the most reliable supply.

[Experimental study on spectra of compressed air microwave plasma].

Science.gov (United States)

Liu, Yong-Xi; Zhang, Gui-Xin; Wang, Qiang; Hou, Ling-Yun

2013-03-01

Using a microwave plasma generator, compressed air microwave plasma was excited under 1 - 5 atm pressures. Under different pressures and different incident microwave power, the emission spectra of compressed air microwave plasma were studied with a spectra measuring system. The results show that continuum is significant at atmospheric pressure and the characteristic will be weakened as the pressure increases. The band spectra intensity will be reduced with the falling of the incident microwave power and the band spectra were still significant. The experimental results are valuable to studying the characteristics of compressed air microwave plasma and the generating conditions of NO active groups.

Emissions of toxic pollutants from compressed natural gas and low sulfur diesel-fueled heavy-duty transit buses tested over multiple driving cycles.

Science.gov (United States)

Kado, Norman Y; Okamoto, Robert A; Kuzmicky, Paul A; Kobayashi, Reiko; Ayala, Alberto; Gebel, Michael E; Rieger, Paul L; Maddox, Christine; Zafonte, Leo

2005-10-01

The number of heavy-duty vehicles using alternative fuels such as compressed natural gas (CNG) and new low-sulfur diesel fuel formulations and equipped with after-treatment devices are projected to increase. However, few peer-reviewed studies have characterized the emissions of particulate matter (PM) and other toxic compounds from these vehicles. In this study, chemical and biological analyses were used to characterize the identifiable toxic air pollutants emitted from both CNG and low-sulfur-diesel-fueled heavy-duty transit buses tested on a chassis dynamometer over three transient driving cycles and a steady-state cruise condition. The CNG bus had no after-treatment, and the diesel bus was tested first equipped with an oxidation catalyst (OC) and then with a catalyzed diesel particulate filter (DPF). Emissions were analyzed for PM, volatile organic compounds (VOCs; determined on-site), polycyclic aromatic hydrocarbons (PAHs), and mutagenic activity. The 2000 model year CNG-fueled vehicle had the highest emissions of 1,3-butadiene, benzene, and carbonyls (e.g., formaldehyde) of the three vehicle configurations tested in this study. The 1998 model year diesel bus equipped with an OC and fueled with low-sulfur diesel had the highest emission rates of PM and PAHs. The highest specific mutagenic activities (revertants/microg PM, or potency) and the highest mutagen emission rates (revertants/mi) were from the CNG bus in strain TA98 tested over the New York Bus (NYB) driving cycle. The 1998 model year diesel bus with DPF had the lowest VOCs, PAH, and mutagenic activity emission. In general, the NYB driving cycle had the highest emission rates (g/mi), and the Urban Dynamometer Driving Schedule (UDDS) had the lowest emission rates for all toxics tested over the three transient test cycles investigated. Also, transient emissions were, in general, higher than steady-state emissions. The emissions of toxic compounds from an in-use CNG transit bus (without an oxidation

Performance analysis of hybrid PV/diesel/battery system using HOMER: A case study Sabah, Malaysia

International Nuclear Information System (INIS)

Halabi, Laith M.; Mekhilef, Saad; Olatomiwa, Lanre; Hazelton, James

2017-01-01

Highlights: • The performance of two decentralized power stations in Malaysia has been studied. • All possible scenarios of hybrid PV/diesel/battery system have been analyzed. • A comparison with the optimum design was included in this work using HOMER. • Sensitivity analysis showing the impact of main factors on the system was examined. • The advantages/disadvantages of utilizing each scenario are showed and clarified. - Abstract: This study considered two decentralized power stations in Sabah, Malaysia; each contains different combination of photovoltaic (PV), diesel generators, system converters, and storage batteries. The work was built upon previous related site surveys and data collections from each site. Verification of the site data sets, simulation of different operational scenarios, and a comparison with the optimum design were all considered in the work. This includes all possible standalone diesel generators, hybrid PV/diesel/battery, and 100% PV/battery scenarios for the proposed stations. HOMER software has been used in the modeling entire systems. The operational behaviors of different PV penetration levels were analyzed to accurately quantify the impact of PV integration. The performance of these stations was analyzed based on technical, economic and environmental constraints, besides, placing emphasis on comparative cost analysis between different operational scenarios. The results satisfied the load demand with the minimum total net present cost (NPC) and levelized cost of energy (LCOE). Moreover, sensitivity analysis was carried out to represents the effects of changing main parameters, such as; fuel, PV, battery prices, and load demand (load growth) on the system performance. Comparison of all operational behaviors scenarios was carried out to elucidate the advantages/disadvantages of utilizing each scenario. The impact of different PV penetration levels on the system performance and the generation of harmful emissions is also

Tension-Compression Fatigue Behavior of Plain Woven Kenaf/Kevlar Hybrid Composites

Directory of Open Access Journals (Sweden)

Suhad D. Salman

2016-02-01

Full Text Available The applications of hybrid natural/synthetic reinforced polymer composites have been rapidly gaining market share in structural applications due to their remarkable characteristics and the fact that most of the components made of these materials are subjected to cyclic loading. Their fatigue properties have received a lot of attention because predicting their behavior is a challenge due to the effects of the synergies between the fibers. The purpose of this work is to characterize the tension, compression, and tensile-compression fatigue behavior of six layers of Kevlar hybridized with one layer of woven kenaf reinforced epoxy, at a 35% weight fraction. Fatigue tests were carried out and loaded cyclically at 60%, 70%, 80%, and 90% of their ultimate compressive stress. The results give a complete description for tensile and compression properties and could be used to predict fatigue-induced failure mechanisms.

Compressibility of air in fibrous materials

DEFF Research Database (Denmark)

Tarnow, Viggo

1996-01-01

The dynamic compressibility of air in fibrous materials has been computed for two assumed configurations of fibers which are close to the geometry of real fiber materials. Models with parallel cylinders placed in a regular square lattice and placed randomly are treated. For these models...... the compressibility is computed approximately from the diameter and mean distances between cylinders. This requires calculation of the air temperature, which is calculated for cylinders in a regular lattive by the Wigner-Seitz cell approximation. In the case of random placement, the calculation is done by a summation...... over thermal waves from all fibers, and by a self-consistent procedure. Figuren of the compressibility in the frequency range 10-100 000 Hz, are given for diameter of the cylinders of 6.8 µm, and mean distances between them from 50 to 110 µm, which corresponds to glass wool with a density of 40 to 16...

Effect of compression ratio, nozzle opening pressure, engine load, and butanol addition on nanoparticle emissions from a non-road diesel engine.

Science.gov (United States)

Maurya, Rakesh Kumar; Saxena, Mohit Raj; Rai, Piyush; Bhardwaj, Aashish

2018-05-01

Currently, diesel engines are more preferred over gasoline engines due to their higher torque output and fuel economy. However, diesel engines confront major challenge of meeting the future stringent emission norms (especially soot particle emissions) while maintaining the same fuel economy. In this study, nanosize range soot particle emission characteristics of a stationary (non-road) diesel engine have been experimentally investigated. Experiments are conducted at a constant speed of 1500 rpm for three compression ratios and nozzle opening pressures at different engine loads. In-cylinder pressure history for 2000 consecutive engine cycles is recorded and averaged data is used for analysis of combustion characteristics. An electrical mobility-based fast particle sizer is used for analyzing particle size and mass distributions of engine exhaust particles at different test conditions. Soot particle distribution from 5 to 1000 nm was recorded. Results show that total particle concentration decreases with an increase in engine operating loads. Moreover, the addition of butanol in the diesel fuel leads to the reduction in soot particle concentration. Regression analysis was also conducted to derive a correlation between combustion parameters and particle number emissions for different compression ratios. Regression analysis shows a strong correlation between cylinder pressure-based combustion parameters and particle number emission.

Experimental investigation on dual fuel operation of acetylene in a DI diesel engine

Energy Technology Data Exchange (ETDEWEB)

Lakshmanan, T. [Department of Mechanical Engineering, Rajarajeswari Engineering College, Adayalampattu, Chennai, 600095 (India); Nagarajan, G. [Internal Combustion Engineering Division, College of Engineering, Anna University, Chennai, 600025 (India)

2010-05-15

Depletion of fossils fuels and environmental degradation have prompted researchers throughout the world to search for a suitable alternative fuel for diesel engine. One such step is to utilize renewable fuels in diesel engines by partial or total replacement of diesel in dual fuel mode. In this study, acetylene gas has been considered as an alternative fuel for compression ignition engine, which has excellent combustion properties. Investigation has been carried out on a single cylinder, air cooled, direct injection (DI), compression ignition engine designed to develop the rated power output of 4.4 kW at 1500 rpm under variable load conditions, run on dual fuel mode with diesel as injected primary fuel and acetylene inducted as secondary gaseous fuel at various flow rates. Acetylene aspiration resulted in lower thermal efficiency. Smoke, HC and CO emissions reduced, when compared with baseline diesel operation. With acetylene induction, due to high combustion rates, NO{sub x} emission significantly increased. Peak pressure and maximum rate of pressure rise also increased in the dual fuel mode of operation due to higher flame speed. It is concluded that induction of acetylene can significantly reduce smoke, CO and HC emissions with a small penalty on efficiency. (author)

A new hybrid model optimized by an intelligent optimization algorithm for wind speed forecasting

International Nuclear Information System (INIS)

Su, Zhongyue; Wang, Jianzhou; Lu, Haiyan; Zhao, Ge

2014-01-01

Highlights: • A new hybrid model is developed for wind speed forecasting. • The model is based on the Kalman filter and the ARIMA. • An intelligent optimization method is employed in the hybrid model. • The new hybrid model has good performance in western China. - Abstract: Forecasting the wind speed is indispensable in wind-related engineering studies and is important in the management of wind farms. As a technique essential for the future of clean energy systems, reducing the forecasting errors related to wind speed has always been an important research subject. In this paper, an optimized hybrid method based on the Autoregressive Integrated Moving Average (ARIMA) and Kalman filter is proposed to forecast the daily mean wind speed in western China. This approach employs Particle Swarm Optimization (PSO) as an intelligent optimization algorithm to optimize the parameters of the ARIMA model, which develops a hybrid model that is best adapted to the data set, increasing the fitting accuracy and avoiding over-fitting. The proposed method is subsequently examined on the wind farms of western China, where the proposed hybrid model is shown to perform effectively and steadily

Impact of Spanish electricity mix, over the period 2008–2030, on the Life Cycle energy consumption and GHG emissions of Electric, Hybrid Diesel-Electric, Fuel Cell Hybrid and Diesel Bus of the Madrid Transportation System

International Nuclear Information System (INIS)

García Sánchez, Juan Antonio; López Martínez, José María; Lumbreras Martín, Julio; Flores Holgado, María Nuria; Aguilar Morales, Hansel

2013-01-01

Highlights: • We assess the performance of 4 buses that run on different alternative fuel types and technologies. • The buses assessed are Fuel Cell-Hybrid Bus, Hybrid Diesel-Electric Bus, Battery Electric Bus, and a Diesel Bus. • We examine the environmental impact caused by the Life Cycle of each vehicle technology, fossil fuel and energy carrier. • Life Cycle of Battery Electric Bus shows that it has a big potential of improvement in terms of environmental impact. - Abstract: In spite of the advanced research in automotive technology, and the improvement of fuels, the road transport sector continues to be an environmental concern, since the increase in transport demand is offsetting the effects of these technological improvements. Therefore, this poses the following question: what combination of technology and fuel is more efficient in terms of energy consumption and green house gas (GHG) emissions? To fully address this question it is necessary to carry out a Life Cycle Assessment (LCA). This paper presents a global LCA of 4 buses that run on the following fuel types and technologies: (1) Fuel Cell- Hybrid Bus, (2) Hybrid Diesel-Electric Bus (series configuration), (3) Battery Electric Bus and (4) Combustion Ignition Engine Bus. The impact categories assessed are: primary energy consumption, fossil energy and GHG emissions. Among the principal results, we can conclude that the Global LCA of buses (3) and (1) (which are the more sensitive pathways to the electricity mix variation) have for the 2008–2030 period a room for improvement of 25.62% and 28.16% in terms of efficiency of fossil energy consumption and a potential GHG emission reduction of 28.70% and 30.88% respectively

4D Trajectory Estimation for Air Traffic Control Automation System Based on Hybrid System Theory

Directory of Open Access Journals (Sweden)

Xin-Min Tang

2012-03-01

Full Text Available To resolve the problem of future airspace management under great traffic flow and high density condition, 4D trajectory estimation has become one of the core technologies of the next new generation air traffic control automation system. According to the flight profile and the dynamics models of different aircraft types under different flight conditions, a hybrid system model that switches the aircraft from one flight stage to another with aircraft state changing continuously in one state is constructed. Additionally, air temperature and wind speed are used to modify aircraft true airspeed as well as ground speed, and the hybrid system evolution simulation is used to estimate aircraft 4D trajectory. The case study proves that 4D trajectory estimated through hybrid system model can image the flight dynamic states of aircraft and satisfy the needs of the planned flight altitude profile.KEY WORDSair traffic management, 4D trajectory estimation, hybrid system model, aircraft dynamic model

Numerical modeling on homogeneous charge compression ignition combustion engine fueled by diesel-ethanol blends

Directory of Open Access Journals (Sweden)

Hanafi H.

2016-01-01

Full Text Available This paper investigates the performance and emission characteristics of HCCI engines fueled with oxygenated fuels (ethanol blend. A modeling study was conducted to investigate the impact of ethanol addition on the performance, combustion and emission characteristics of a Homogeneous Charge Compression Ignition (HCCI engine fueled by diesel. One dimensional simulation was conducted using the renowned commercial software for diesel and its blend fuels with 5% (E5 and 10% ethanol (E10 (in vol. under full load condition at variable engine speed ranging from 1000 to 2750 rpm with 250 rpm increment. The model was then validated with other researcher’s experimental result. Model consists of intake and exhaust systems, cylinder, head, valves and port geometries. Performance tests were conducted for volumetric efficiency, brake engine torque, brake power, brake mean effective pressure, brake specific fuel consumption, and brake thermal efficiency, while exhaust emissions were analyzed for carbon monoxide (CO and unburned hydrocarbons (HC. The results showed that blending diesel with ethanol increases the volumetric efficiency, brake specific fuel consumption and brake thermal efficiency, while it decreases brake engine torque, brake power and brake mean effective pressure. In term of emission characteristics, the CO emissions concentrations in the engine exhaust decrease significantly with ethanol as additive. But for HC emission, its concentration increase when apply in high engine speed. In conclusion, using Ethanol as fuel additive blend with Diesel operating in HCCI shows a good result in term of performance and emission in low speed but not recommended to use in high speed engine. Ethanol-diesel blends need to researched more to make it commercially useable.

Organizational forms promoting wind power development. Organizational and legal evaluation, energy- and environmental analysis and socio-economic analysis of wind turbine location along railways

International Nuclear Information System (INIS)

1997-12-01

Modernization of the train material and transition from diesel-driven to el-driven trains result in reduced air pollution in Denmark. The purpose of this study is to define, concretize and compare organizational forms for use of wind power as the 'green' electric power for train operation. An investment into an wind turbine array with 500 kW wind turbines in roughness class 2 would be repaid in 7.9 year period. Air pollution abatement together with improved socio-economic structure due to growing employment would be achieved. Several models of 'green' electrification of the national railways are given, both for state- and privately owned wind power plants. (EG)

Multiple time-scale optimization scheduling for islanded microgrids including PV, wind turbine, diesel generator and batteries

DEFF Research Database (Denmark)

Xiao, Zhao xia; Nan, Jiakai; Guerrero, Josep M.

2017-01-01

A multiple time-scale optimization scheduling including day ahead and short time for an islanded microgrid is presented. In this paper, the microgrid under study includes photovoltaics (PV), wind turbine (WT), diesel generator (DG), batteries, and shiftable loads. The study considers the maximum...... efficiency operation area for the diesel engine and the cost of the battery charge/discharge cycle losses. The day-ahead generation scheduling takes into account the minimum operational cost and the maximum load satisfaction as the objective function. Short-term optimal dispatch is based on minimizing...

A Novel 1D Hybrid Chaotic Map-Based Image Compression and Encryption Using Compressed Sensing and Fibonacci-Lucas Transform

Directory of Open Access Journals (Sweden)

Tongfeng Zhang

2016-01-01

Full Text Available A one-dimensional (1D hybrid chaotic system is constructed by three different 1D chaotic maps in parallel-then-cascade fashion. The proposed chaotic map has larger key space and exhibits better uniform distribution property in some parametric range compared with existing 1D chaotic map. Meanwhile, with the combination of compressive sensing (CS and Fibonacci-Lucas transform (FLT, a novel image compression and encryption scheme is proposed with the advantages of the 1D hybrid chaotic map. The whole encryption procedure includes compression by compressed sensing (CS, scrambling with FLT, and diffusion after linear scaling. Bernoulli measurement matrix in CS is generated by the proposed 1D hybrid chaotic map due to its excellent uniform distribution. To enhance the security and complexity, transform kernel of FLT varies in each permutation round according to the generated chaotic sequences. Further, the key streams used in the diffusion process depend on the chaotic map as well as plain image, which could resist chosen plaintext attack (CPA. Experimental results and security analyses demonstrate the validity of our scheme in terms of high security and robustness against noise attack and cropping attack.

Analysis of Engine Parameters at Using Diesel-LPG and Diesel-CNG Mixture in Compression-ignition Engine

Directory of Open Access Journals (Sweden)

Michal Jukl

2014-01-01

Full Text Available This work is aimed on influence of diesel engine parameters that is used with mixture of gas and diesel fuel. The first part of the article describes diesel fuel systems where small part of diesel fuel is replaced by LPG or CNG fuel. These systems are often called as Diesel-Gas systems. Next part of the article focuses on tested car and measurement equipment. Measurement was performed by common-rail diesel engine in Fiat Doblň. Tests were carried out in laboratories of the Department of Engineering and Automobile Transport at the Mendel University in Brno. They were observed changes between emissions of used fuels – diesel without addition of gas, diesel + LPG and diesel + CNG mixture. It was found that that the addition of gas had positive effect on the performance parameters and emissions.

Life cycle air quality impacts of conventional and alternative light-duty transportation in the United States.

Science.gov (United States)

Tessum, Christopher W; Hill, Jason D; Marshall, Julian D

2014-12-30

Commonly considered strategies for reducing the environmental impact of light-duty transportation include using alternative fuels and improving vehicle fuel economy. We evaluate the air quality-related human health impacts of 10 such options, including the use of liquid biofuels, diesel, and compressed natural gas (CNG) in internal combustion engines; the use of electricity from a range of conventional and renewable sources to power electric vehicles (EVs); and the use of hybrid EV technology. Our approach combines spatially, temporally, and chemically detailed life cycle emission inventories; comprehensive, fine-scale state-of-the-science chemical transport modeling; and exposure, concentration-response, and economic health impact modeling for ozone (O3) and fine particulate matter (PM2.5). We find that powering vehicles with corn ethanol or with coal-based or "grid average" electricity increases monetized environmental health impacts by 80% or more relative to using conventional gasoline. Conversely, EVs powered by low-emitting electricity from natural gas, wind, water, or solar power reduce environmental health impacts by 50% or more. Consideration of potential climate change impacts alongside the human health outcomes described here further reinforces the environmental preferability of EVs powered by low-emitting electricity relative to gasoline vehicles.

30 CFR 77.411 - Compressed air and boilers; general.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Compressed air and boilers; general. 77.411 Section 77.411 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... COAL MINES Safeguards for Mechanical Equipment § 77.411 Compressed air and boilers; general. All...