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02354 A review of energy models
13 Altemative energy supplies (others, including economics) electric power load levelling. The desired outcome would be to show that the costs of generating heat energy with the seawater-source heat pump are significantly less than those with the air-source heat pump and the oil-fired system. Additionally, the carbon dioxide emissions for the seawater-source heat pump compare favourably as they maybe less than those for the other conventional assumed systems described.
06/02354
A review of energy models
Jebaraj, S. and Iniyan, S. Renewable and Sustainable Energy Reriews, 2006, 10. (4), 281 311. Energy is a vital input for social and economic development of any nation. With increasing agricultural and industrial activities in the country, the demand for energy is also increasing. Formulation of an energy model will help in the proper allocation of widely available renewable energy sources such as solar, wind, bioenergy and small hydropower in meeting the future energy demand in India. During the last decade several new concepts of energy planning and management such as decentralized planning, energy conservation through improved technologies, waste recycling, integrated energy planning, introduction of renewable energy sources and energy forecasting have emerged. In this paper an attempt has been made to understand and review the various emerging issues related to the energy modelling. The different types of models such as energy planning models, energy supplydemand models, forecasting models, renewable energy models, emission reduction models, optimization models have been reviewed and presented. Also, models based on neural network and fuzzy theory have been reviewed and discussed. The review paper on energy modelling will help the energy planners, researchers and policy makers widely.
06•02355 An agro-economic analysis of willow cultivation in Poland Ericsson, K. et al. Biomass and Bioenergy, 2006, 30, (l), 16-27. Bioenergy is recognized as the most important renewable energy source in Poland in several national policy documents. This has spurred an in increasing interest in energy crops, particularly willow, due to the large areas of arable land in Poland. However, in order for willow to be adopted by farmers, this crop must be perceived to be at least as profitable as cereal crops, such as wheat and barley, which compete for the same land. The objective of this study was to calculate the economics of growing willow on relatively large farms from a farmer's perspective in Poland. An additional objective was to relate the viability of growing willow to that of growing wheat and barley. The calculations show that growing willow can indeed be an economically viable alternative to wheat and barley. At the current Polish price of wood chips (about 33 PLN/MWh or 7.5 £/MWh), the viability of willow is similar to that of barley given the assumptions on yields, etc. Wheat is the most viable crop of the three crops studied. Willow, however, is more profitable than both wheat and barley assuming a wood chip price of 50 PLN/MWh (11 £/MWh), which better represents the price in Europe as a whole. Despite good viability, willow is unlikely to be adopted by a great number of farmers without active support mechanisms and long-term stability of the status of energy crops in the Polish and the EU common agricultural policy.
06/02356 Design, simulation, and testing of a novel hydraulic power take-off system for the Pelamis wave energy converter Henderson, R. et al. Renewable Energy, 2006, 31, (2), 271 283. The economic viability of a wave energy converter depends largely on its power take-off system. Active control of the power take-off is necessary to maximize power capture across a range of sea-states and can also improve survivability. The high force, low speed regime of wave energy conversion makes it a suitable application for highpressure hydraulics. This paper describes the hydraulic power take-off system employed in the Pelamis wave energy converter. The process of the system's development is presented, including simulation and laboratory tests at 1/7th and fullscale. Results of efficiency measurements are also presented.
06•02357 Developments in the design of the PS Frog Mk 5 wave energy converter McCabe, A. P. et al. Renewable Energy, 2006, 31, (2), 141 151. This paper describes one of the innovative wave energy converters under development by the Lancaster University Renewable Energy Group. An offshore point-absorber wave energy converter, PS Frog Mk 5 consists of a large buoyant paddle with an integral ballasted 'handle' hanging below it. The waves act on the blade of the paddle and the ballast beneath provides the necessary reaction. When the WEC is pitching, power is extracted by partially resisting the sliding of a powertake-off mass, which moves in guides above sea level. Totally enclosed in a steel hull, with no external moving parts, PS Frog Mk. 5 is at least as robust as a ship and the survivability of the device is currently under investigation, though such work is beyond the scope of this paper. Such a device could be very economic in terms of power output per unit of
358
Fuel and Energy Abstracts September 2006
capital cost. New inventive steps with experimental results and computer studies have led to promising improvements to the hull shape. The WEC is maintained in a resonant state by the use of special means to maintain a high dynamic magnifier in irregular seas. A robust feedback control system has been developed to ensure stability and maintain efficient power take-off. Some of these developments are described and illustrated with the results of computer simulations that show power outputs and device motion over a range of conditions. It is shown that useful advances have been made, with the power capture bordering on 2 MW in an increasing proportion of sea states.
06102358 Dynamic life cycle assessment (LCA) of renewable energy technologies Pehnt, M. Renewable Energy, 2006, 31, (1), 55-71. Before new technologies enter the market, their environmental superiority over competing options must be asserted based on a life cycle approach. However, when applying the prevailing status-quo life cycle assessment (LCA) approach to future renewable energy systems, one does not distinguish between impacts which are 'imported' into the system due to the 'background system' (e.g. due to supply of materials or final energy for the production of the energy system), and what is the improvement potential of these technologies compared to competitors (e.g. due to process and system innovations or diffusion effects). This paper investigates a dynamic approach towards the LCA of renewable energy technologies and proves that for all renewable energy chains, the inputs of finite energy resources and emissions of greenhouse gases are extremely low compared with the conventional system. With regard to the other environmental impacts the findings do not reveal any clear verdict for or against renewable energies. Future development will enable a further reduction of environmental impacts of renewable energy systems, Different factors are responsible for this development, such as progress with respect to technical parameters of energy converters, in particular, improved efficiency; emissions characteristics; increased lifetime, etc.; advances with regard to the production process of energy converters and fuels; and advances with regard to 'external' services originating from conventional energy and transport systems, for instance, improved electricity or process heat supply for system production and ecologically optimized transport systems for fuel transportation. The application of renewable energy sources might modify not only the background system, but also further downstream aspects, such as consumer behaviour. This effect is, however, strongly context and technology dependent.
06•02359 Evaluation of alternative fuels for residential heating in Turkey using analytic network process (ANP) with group decision-making Erdogmus, S. et al. Renewable and Sustainable Energy Reviews, 2006, 10, (3), 269 279. Energy policies require cheap and continuous energy, which is needed in Turkey for further development. Implementation of a successful energy policy requires political and economical institutions to take responsibility and to adopt adapt to changes easily. Energy policy generally consists of institutional structure, in which decisions related to technology, economy and energy are made, and also consists of supply-demand management in short term and planning in long term. Energy demand is closely related to social and economic structure of a society. In the long term development of energy demand, developmental structure of society (economic growth, life style, socio-economic factors), technological development and energy prices play important roles as determining factors. In this study, evaluation of most suitable fuel which can be used for residential heating was made using ANP with group decision-making.
06/02360 GIS-based evaluation of multifarious local renewable energy sources: a case study of the Chigu area of southwestern Taiwan Yue, C.-D. and Wang, S.-S. Energy Policy, 2006, 34, (6), 730-742. The issue of regulating greenhouse gas emissions of developing countries is one of the main reasons for the USA's retreat from ratifying the Kyoto Protocol, and this deserves particular attention in order to ensure that a robust international climate policy exists in the future. Enabling developing countries to move toward low-carbon energy systems would enhance the feasibility for their participation in mitigating greenhouse gas emissions. This study evaluates wind, solar, and biomass energy sources in a rural area of Chigu in south-western Taiwan by means of analysing technical, economic, environmental, and political implications in order to establish an evaluation model for developing local renewable energy sources. The adopted approach evaluates local potentials of renewable energy sources with the aid of a geographic information system according to actual local conditions, and allows the assessment to consider local potentials and restrictions such as climate conditions, land uses, and ecological environments, thus enabling a more-accurate assessment than is possible with evaluations on an approximate basis. These results may help build a
06/02354
A review of energy models
Jebaraj, S. and Iniyan, S. Renewable and Sustainable Energy Reriews, 2006, 10. (4), 281 311. Energy is a vital input for social and economic development of any nation. With increasing agricultural and industrial activities in the country, the demand for energy is also increasing. Formulation of an energy model will help in the proper allocation of widely available renewable energy sources such as solar, wind, bioenergy and small hydropower in meeting the future energy demand in India. During the last decade several new concepts of energy planning and management such as decentralized planning, energy conservation through improved technologies, waste recycling, integrated energy planning, introduction of renewable energy sources and energy forecasting have emerged. In this paper an attempt has been made to understand and review the various emerging issues related to the energy modelling. The different types of models such as energy planning models, energy supplydemand models, forecasting models, renewable energy models, emission reduction models, optimization models have been reviewed and presented. Also, models based on neural network and fuzzy theory have been reviewed and discussed. The review paper on energy modelling will help the energy planners, researchers and policy makers widely.
06•02355 An agro-economic analysis of willow cultivation in Poland Ericsson, K. et al. Biomass and Bioenergy, 2006, 30, (l), 16-27. Bioenergy is recognized as the most important renewable energy source in Poland in several national policy documents. This has spurred an in increasing interest in energy crops, particularly willow, due to the large areas of arable land in Poland. However, in order for willow to be adopted by farmers, this crop must be perceived to be at least as profitable as cereal crops, such as wheat and barley, which compete for the same land. The objective of this study was to calculate the economics of growing willow on relatively large farms from a farmer's perspective in Poland. An additional objective was to relate the viability of growing willow to that of growing wheat and barley. The calculations show that growing willow can indeed be an economically viable alternative to wheat and barley. At the current Polish price of wood chips (about 33 PLN/MWh or 7.5 £/MWh), the viability of willow is similar to that of barley given the assumptions on yields, etc. Wheat is the most viable crop of the three crops studied. Willow, however, is more profitable than both wheat and barley assuming a wood chip price of 50 PLN/MWh (11 £/MWh), which better represents the price in Europe as a whole. Despite good viability, willow is unlikely to be adopted by a great number of farmers without active support mechanisms and long-term stability of the status of energy crops in the Polish and the EU common agricultural policy.
06/02356 Design, simulation, and testing of a novel hydraulic power take-off system for the Pelamis wave energy converter Henderson, R. et al. Renewable Energy, 2006, 31, (2), 271 283. The economic viability of a wave energy converter depends largely on its power take-off system. Active control of the power take-off is necessary to maximize power capture across a range of sea-states and can also improve survivability. The high force, low speed regime of wave energy conversion makes it a suitable application for highpressure hydraulics. This paper describes the hydraulic power take-off system employed in the Pelamis wave energy converter. The process of the system's development is presented, including simulation and laboratory tests at 1/7th and fullscale. Results of efficiency measurements are also presented.
06•02357 Developments in the design of the PS Frog Mk 5 wave energy converter McCabe, A. P. et al. Renewable Energy, 2006, 31, (2), 141 151. This paper describes one of the innovative wave energy converters under development by the Lancaster University Renewable Energy Group. An offshore point-absorber wave energy converter, PS Frog Mk 5 consists of a large buoyant paddle with an integral ballasted 'handle' hanging below it. The waves act on the blade of the paddle and the ballast beneath provides the necessary reaction. When the WEC is pitching, power is extracted by partially resisting the sliding of a powertake-off mass, which moves in guides above sea level. Totally enclosed in a steel hull, with no external moving parts, PS Frog Mk. 5 is at least as robust as a ship and the survivability of the device is currently under investigation, though such work is beyond the scope of this paper. Such a device could be very economic in terms of power output per unit of
358
Fuel and Energy Abstracts September 2006
capital cost. New inventive steps with experimental results and computer studies have led to promising improvements to the hull shape. The WEC is maintained in a resonant state by the use of special means to maintain a high dynamic magnifier in irregular seas. A robust feedback control system has been developed to ensure stability and maintain efficient power take-off. Some of these developments are described and illustrated with the results of computer simulations that show power outputs and device motion over a range of conditions. It is shown that useful advances have been made, with the power capture bordering on 2 MW in an increasing proportion of sea states.
06102358 Dynamic life cycle assessment (LCA) of renewable energy technologies Pehnt, M. Renewable Energy, 2006, 31, (1), 55-71. Before new technologies enter the market, their environmental superiority over competing options must be asserted based on a life cycle approach. However, when applying the prevailing status-quo life cycle assessment (LCA) approach to future renewable energy systems, one does not distinguish between impacts which are 'imported' into the system due to the 'background system' (e.g. due to supply of materials or final energy for the production of the energy system), and what is the improvement potential of these technologies compared to competitors (e.g. due to process and system innovations or diffusion effects). This paper investigates a dynamic approach towards the LCA of renewable energy technologies and proves that for all renewable energy chains, the inputs of finite energy resources and emissions of greenhouse gases are extremely low compared with the conventional system. With regard to the other environmental impacts the findings do not reveal any clear verdict for or against renewable energies. Future development will enable a further reduction of environmental impacts of renewable energy systems, Different factors are responsible for this development, such as progress with respect to technical parameters of energy converters, in particular, improved efficiency; emissions characteristics; increased lifetime, etc.; advances with regard to the production process of energy converters and fuels; and advances with regard to 'external' services originating from conventional energy and transport systems, for instance, improved electricity or process heat supply for system production and ecologically optimized transport systems for fuel transportation. The application of renewable energy sources might modify not only the background system, but also further downstream aspects, such as consumer behaviour. This effect is, however, strongly context and technology dependent.
06•02359 Evaluation of alternative fuels for residential heating in Turkey using analytic network process (ANP) with group decision-making Erdogmus, S. et al. Renewable and Sustainable Energy Reviews, 2006, 10, (3), 269 279. Energy policies require cheap and continuous energy, which is needed in Turkey for further development. Implementation of a successful energy policy requires political and economical institutions to take responsibility and to adopt adapt to changes easily. Energy policy generally consists of institutional structure, in which decisions related to technology, economy and energy are made, and also consists of supply-demand management in short term and planning in long term. Energy demand is closely related to social and economic structure of a society. In the long term development of energy demand, developmental structure of society (economic growth, life style, socio-economic factors), technological development and energy prices play important roles as determining factors. In this study, evaluation of most suitable fuel which can be used for residential heating was made using ANP with group decision-making.
06/02360 GIS-based evaluation of multifarious local renewable energy sources: a case study of the Chigu area of southwestern Taiwan Yue, C.-D. and Wang, S.-S. Energy Policy, 2006, 34, (6), 730-742. The issue of regulating greenhouse gas emissions of developing countries is one of the main reasons for the USA's retreat from ratifying the Kyoto Protocol, and this deserves particular attention in order to ensure that a robust international climate policy exists in the future. Enabling developing countries to move toward low-carbon energy systems would enhance the feasibility for their participation in mitigating greenhouse gas emissions. This study evaluates wind, solar, and biomass energy sources in a rural area of Chigu in south-western Taiwan by means of analysing technical, economic, environmental, and political implications in order to establish an evaluation model for developing local renewable energy sources. The adopted approach evaluates local potentials of renewable energy sources with the aid of a geographic information system according to actual local conditions, and allows the assessment to consider local potentials and restrictions such as climate conditions, land uses, and ecological environments, thus enabling a more-accurate assessment than is possible with evaluations on an approximate basis. These results may help build a