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01378 Power strategies for maximum control structure of a wind energy conversion system with a synchronous machine
13 Altemative energy supplies (others, including economics) 06/01377 Kuwait
Potential wind power generation in the State of
Al-Nassar, W. et al. Renewable Energy, 2005, 30, (14), 2149 2161. The wind characteristics of six locations in the State of Kuwait have been assessed. The a n n u a l average wind speed for the considered sites r a n g e d from 3.7 to 5.5 m/s and a m e a n wind power density from 80 to 167 W / m 2 at standard height of 10 m. The W e i b u l l p a r a m e t e r s and power density of each station have been d e t e r m i n e d using W e i b u l l distribution. The wind data at heights 15, 20, 25 and 30 m were obtained by extrapolation of the 10 m data using the Power-Law. The p o t e n t i a l wind energy at different heights was estimated using W e i b u l l parameters. M a x i m u m power density is found at 30 m height which varies between 130 and 275 W/m 2 with 70% increase from the standard height indicating fairly p o t e n t i a l wind energy especially in the n o r t h e r n p a r t of the country. The highest p o t e n t i a l wind power was found during the s u m m e r season which is the p e a k d e m a n d season of electricity in Kuwait.
06/01378 Power strategies for maximum control structure of a wind energy conversion system with a synchronous machine Bouscayrol, A. et al. Renewable Energy, 2005, 30, (15), 2273 2288. The control of a wind energy conversion system can be d e c o m p o s e d into two parts: a local control d e p e n d i n g on the power structure and a global control (strategy) deduced from global considerations. The local p a r t ensures an efficient energy m a n a g e m e n t of each c o m p o n e n t of the system. The local control structure can be deduced from the E n e r g e t i c Macroscopic R e p r e s e n t a t i o n , which is a graphical description of the system according to action and reaction principle. Using inversion rules, the deduced control structure is composed of a m a x i m u m of control operations and m e a s u r e m e n t s . The global control part is i n d e p e n d e n t of the power structure. This strategy part leads to achieve power objectives (active and reactive power targets) and system constraints (machine efficiency and D C bus limitation). Several strategies can be defined for the same system. These control decompositions are applied to a wind generation system composed of a p e r m a n e n t m a g n e t synchronous generator and two three-phase converters. Simulation results are provided for a 600 k W wind energy conversion system.
06/01379 aspects
Southern spanish windmills: technological
Rojas-Sola, J. I. and Amezcua-Oggtyar, J. M. Renewable Energy, 2005, 30,(13), 1943 1953. This p a p e r shows the study carried out in a doctoral thesis about windmills in south-east Spain, in the area of C a m p o de N/jar in the province of Almeria. It intends to pay h o m a g e to Spanish windmills as a way of c o m m e m o r a t i n g the fourth centenary of the m a s t e r w o r k of Spanish Literature, 'Don Quixote' in which the silhouette of the windmill is a pervading symbol. W h e a t milling has been an i m p o r t a n t factor in the socio-economic d e v e l o p m e n t of rural Spain for centuries. The type of mill used d e p e n d e d on the energy resources available, wind or water. In the C a m p o de N/jar (Almeria, Andalusia, Spain), wind is the principal energy source, and therefore, windmills were widely used, as in other areas of Spain. In this paper, the authors study the technological conditions of these old windmills, carry out a wind evaluation of the area, and calculate the power and m o m e n t u m of these windmills with a discussion of the results.
Others, including economics 06/01380 An application of a combined wind and solar energy system in Izmir Ozdamar, A. et al. Renewable and Sustainable Energy Reviews, 2005, 9, (6), 624 637. In this work, a combined system which is p r o d u c e d electrical energy from both solar radiation via solar cells and wind energy by using wind turbine was studied. For wind energy, m e a s u r e m e n t s of wind velocities at 12 m height were taken. Then, these values were calculated for 42 m by using H e l l m a n n equation. After that, wind energy converted to the electrical energy. However, value of solar radiation from solar cells was t a k e n at the o p t i m u m slope angle of collector which provided higher energy p r o d u c t i o n for each 1 h during this application. Thus, obtained data from each system were used together for finding total energy. For this study, m e a s u r e m e n t s , which would be used in calculation of wind energy and solar energy were taken for four years between 1995 and 1998 in Izmir. As a result, energy of the combined system could support each other w h e n one of them produces energy insufficiently.
06•01381 An econometric analysis of energy input-output in Turkish agriculture Hatirli, S. A. et al. Renewable and Sustainable Energy Reviews, 2005, 9, (6), 608 623. This study analyzes energy use and investigates influences of energy inputs and energy forms on o u t p u t levels in Turkish agriculture d u r i n g the period 1975 2000. The o u t p u t level was calculated in the form of a n n u a l grain equivalent at aggregate level for 104 agricultural commodities except livestock products. O u t p u t level was specified as a function of total physical, fertilizer and seed energy, and ordinary least squares was employed to estimate equation parameters. The results show that total energy input has increased from 19.6 GJ/ha in 1975 to 45.7 G J / h a in 2000, whereas total o u t p u t energy has risen from 27.1 GJ/ha to a level of 39.1 GJ/ha. E n e r g y efficiency indicators, i n p u ~ o u t p u t ratio, energy productivity and net energy have declined over the examined period. Total physical and fertilizer energy, particularly nitrogen, significantly contributed to o u t p u t level with elasticities of 0.24 and 0.14, respectively. The results also revealed that nonrenewable, direct and indirect energy forms had a positive i m p a c t on o u t p u t level. Moreover, Turkish agriculture has experienced a substantial increase in non-renewable energy use. This inefficient energy use pattern in the Turkish agriculture can create some e n v i r o n m e n t a l p r o b l e m s such as increase in global warming, CO2 emissions, and non-sustainability. Thus, policy makers should u n d e r t a k e new policy tools to ensure sustainability and efficient energy use.
06•01382 An integrated assessment of energy conversion processes by means of thermodynamic, economic and environmental parameters Tonon, S. et al. Energy, 2006, 31, (1), 149 163. A comprehensive m e t h o d of analysis based on energetic, exergetic, emergetic and economic evaluations is p r o p o s e d in the p a p e r and the application presented. The m e t h o d is applied to selected energy conversion processes (hydroelectric and thermoelectric ones and b i o e t h a n o l production). Results are p r e s e n t e d and c o m p a r e d while general considerations a b o u t the effectiveness of the different approaches are suggested. Emissions to the e n v i r o n m e n t are also evaluated. Suitable p e r f o r m a n c e indicators developed within the p r o p o s e d m e t h o d o l o g i c a l f r a m e w o r k are defined and discussed accordingly. The m e t h o d p r o p o s e d here is addressed to policy makers, operators and designers working in the field of energy supply and conversion. In the authors' opinion, by jointly applying and comparing all of the methods suggested in the paper, valuable information about p l a n t performance and possible areas of i m p r o v e m e n t are obtained. This can be helpful in the decision-making process.
06•01383 Applying multi-objective genetic algorithms in green building design optimization Wang, W. et al. Building and Environment, 2005, 40, (11), 1512 1525. Since buildings have considerable impacts on the environment, it has b e c o m e necessary to pay more attention to e n v i r o n m e n t a l p e r f o r m a n c e in building design. However, it is a difficult task to find better design alternatives satisfying several conflicting criteria, especially, economical and e n v i r o n m e n t a l performance. This p a p e r presents a multiobjective optimization m o d e l that could assist designers in green building design. Variables in the m o d e l include those p a r a m e t e r s that are usually d e t e r m i n e d at the conceptual design stage and that have critical influence on building performance. Life cycle analysis m e t h o d o l o g y is employed to evaluate design alternatives for both economical and e n v i r o n m e n t a l criteria. Life cycle e n v i r o n m e n t a l impacts are evaluated in terms of expanded cumulative exergy consumption, which is the sum of exergy c o n s u m p t i o n due to resource inputs and a b a t e m e n t exergy required to recover the negative impacts due to waste emissions. A multi-objective genetic algorithm is employed to find optimal solutions. A case study is p r e s e n t e d and the effectiveness of the approach is d e m o n s t r a t e d for identifying a n u m b e r of P a r e t o optimal solutions for green building design.
06/01384 Computational analysis of performance and flow investigation on wells turbine for wave energy conversion D h a n a s e k a r a n , T. S. and Govardhan, M. Renewable Energy, 2005, 30, (14), 2129 2147. Wells turbine is a self-rectifying airflow turbine capable of converting p n e u m a t i c power of the periodically reversing air stream in oscillating water column into mechanical energy. This p a p e r reports the c o m p u t a t i o n a l analysis on performance and aerodynamics of Wells turbine with the N A C A 0021 constant chord blades. Studies have been m a d e at various flow coefficients covering the entire range of flow coefficients over which the turbine is operable. The p r e s e n t computational model can predict the performance and aerodynamics of the turbine quantitatively and qualitatively. The m o d e l also predicted the flow coefficient at which the turbine stalls, with reasonable accuracy.
Fuel and Energy Abstracts
May 2006
205
Potential wind power generation in the State of
Al-Nassar, W. et al. Renewable Energy, 2005, 30, (14), 2149 2161. The wind characteristics of six locations in the State of Kuwait have been assessed. The a n n u a l average wind speed for the considered sites r a n g e d from 3.7 to 5.5 m/s and a m e a n wind power density from 80 to 167 W / m 2 at standard height of 10 m. The W e i b u l l p a r a m e t e r s and power density of each station have been d e t e r m i n e d using W e i b u l l distribution. The wind data at heights 15, 20, 25 and 30 m were obtained by extrapolation of the 10 m data using the Power-Law. The p o t e n t i a l wind energy at different heights was estimated using W e i b u l l parameters. M a x i m u m power density is found at 30 m height which varies between 130 and 275 W/m 2 with 70% increase from the standard height indicating fairly p o t e n t i a l wind energy especially in the n o r t h e r n p a r t of the country. The highest p o t e n t i a l wind power was found during the s u m m e r season which is the p e a k d e m a n d season of electricity in Kuwait.
06/01378 Power strategies for maximum control structure of a wind energy conversion system with a synchronous machine Bouscayrol, A. et al. Renewable Energy, 2005, 30, (15), 2273 2288. The control of a wind energy conversion system can be d e c o m p o s e d into two parts: a local control d e p e n d i n g on the power structure and a global control (strategy) deduced from global considerations. The local p a r t ensures an efficient energy m a n a g e m e n t of each c o m p o n e n t of the system. The local control structure can be deduced from the E n e r g e t i c Macroscopic R e p r e s e n t a t i o n , which is a graphical description of the system according to action and reaction principle. Using inversion rules, the deduced control structure is composed of a m a x i m u m of control operations and m e a s u r e m e n t s . The global control part is i n d e p e n d e n t of the power structure. This strategy part leads to achieve power objectives (active and reactive power targets) and system constraints (machine efficiency and D C bus limitation). Several strategies can be defined for the same system. These control decompositions are applied to a wind generation system composed of a p e r m a n e n t m a g n e t synchronous generator and two three-phase converters. Simulation results are provided for a 600 k W wind energy conversion system.
06/01379 aspects
Southern spanish windmills: technological
Rojas-Sola, J. I. and Amezcua-Oggtyar, J. M. Renewable Energy, 2005, 30,(13), 1943 1953. This p a p e r shows the study carried out in a doctoral thesis about windmills in south-east Spain, in the area of C a m p o de N/jar in the province of Almeria. It intends to pay h o m a g e to Spanish windmills as a way of c o m m e m o r a t i n g the fourth centenary of the m a s t e r w o r k of Spanish Literature, 'Don Quixote' in which the silhouette of the windmill is a pervading symbol. W h e a t milling has been an i m p o r t a n t factor in the socio-economic d e v e l o p m e n t of rural Spain for centuries. The type of mill used d e p e n d e d on the energy resources available, wind or water. In the C a m p o de N/jar (Almeria, Andalusia, Spain), wind is the principal energy source, and therefore, windmills were widely used, as in other areas of Spain. In this paper, the authors study the technological conditions of these old windmills, carry out a wind evaluation of the area, and calculate the power and m o m e n t u m of these windmills with a discussion of the results.
Others, including economics 06/01380 An application of a combined wind and solar energy system in Izmir Ozdamar, A. et al. Renewable and Sustainable Energy Reviews, 2005, 9, (6), 624 637. In this work, a combined system which is p r o d u c e d electrical energy from both solar radiation via solar cells and wind energy by using wind turbine was studied. For wind energy, m e a s u r e m e n t s of wind velocities at 12 m height were taken. Then, these values were calculated for 42 m by using H e l l m a n n equation. After that, wind energy converted to the electrical energy. However, value of solar radiation from solar cells was t a k e n at the o p t i m u m slope angle of collector which provided higher energy p r o d u c t i o n for each 1 h during this application. Thus, obtained data from each system were used together for finding total energy. For this study, m e a s u r e m e n t s , which would be used in calculation of wind energy and solar energy were taken for four years between 1995 and 1998 in Izmir. As a result, energy of the combined system could support each other w h e n one of them produces energy insufficiently.
06•01381 An econometric analysis of energy input-output in Turkish agriculture Hatirli, S. A. et al. Renewable and Sustainable Energy Reviews, 2005, 9, (6), 608 623. This study analyzes energy use and investigates influences of energy inputs and energy forms on o u t p u t levels in Turkish agriculture d u r i n g the period 1975 2000. The o u t p u t level was calculated in the form of a n n u a l grain equivalent at aggregate level for 104 agricultural commodities except livestock products. O u t p u t level was specified as a function of total physical, fertilizer and seed energy, and ordinary least squares was employed to estimate equation parameters. The results show that total energy input has increased from 19.6 GJ/ha in 1975 to 45.7 G J / h a in 2000, whereas total o u t p u t energy has risen from 27.1 GJ/ha to a level of 39.1 GJ/ha. E n e r g y efficiency indicators, i n p u ~ o u t p u t ratio, energy productivity and net energy have declined over the examined period. Total physical and fertilizer energy, particularly nitrogen, significantly contributed to o u t p u t level with elasticities of 0.24 and 0.14, respectively. The results also revealed that nonrenewable, direct and indirect energy forms had a positive i m p a c t on o u t p u t level. Moreover, Turkish agriculture has experienced a substantial increase in non-renewable energy use. This inefficient energy use pattern in the Turkish agriculture can create some e n v i r o n m e n t a l p r o b l e m s such as increase in global warming, CO2 emissions, and non-sustainability. Thus, policy makers should u n d e r t a k e new policy tools to ensure sustainability and efficient energy use.
06•01382 An integrated assessment of energy conversion processes by means of thermodynamic, economic and environmental parameters Tonon, S. et al. Energy, 2006, 31, (1), 149 163. A comprehensive m e t h o d of analysis based on energetic, exergetic, emergetic and economic evaluations is p r o p o s e d in the p a p e r and the application presented. The m e t h o d is applied to selected energy conversion processes (hydroelectric and thermoelectric ones and b i o e t h a n o l production). Results are p r e s e n t e d and c o m p a r e d while general considerations a b o u t the effectiveness of the different approaches are suggested. Emissions to the e n v i r o n m e n t are also evaluated. Suitable p e r f o r m a n c e indicators developed within the p r o p o s e d m e t h o d o l o g i c a l f r a m e w o r k are defined and discussed accordingly. The m e t h o d p r o p o s e d here is addressed to policy makers, operators and designers working in the field of energy supply and conversion. In the authors' opinion, by jointly applying and comparing all of the methods suggested in the paper, valuable information about p l a n t performance and possible areas of i m p r o v e m e n t are obtained. This can be helpful in the decision-making process.
06•01383 Applying multi-objective genetic algorithms in green building design optimization Wang, W. et al. Building and Environment, 2005, 40, (11), 1512 1525. Since buildings have considerable impacts on the environment, it has b e c o m e necessary to pay more attention to e n v i r o n m e n t a l p e r f o r m a n c e in building design. However, it is a difficult task to find better design alternatives satisfying several conflicting criteria, especially, economical and e n v i r o n m e n t a l performance. This p a p e r presents a multiobjective optimization m o d e l that could assist designers in green building design. Variables in the m o d e l include those p a r a m e t e r s that are usually d e t e r m i n e d at the conceptual design stage and that have critical influence on building performance. Life cycle analysis m e t h o d o l o g y is employed to evaluate design alternatives for both economical and e n v i r o n m e n t a l criteria. Life cycle e n v i r o n m e n t a l impacts are evaluated in terms of expanded cumulative exergy consumption, which is the sum of exergy c o n s u m p t i o n due to resource inputs and a b a t e m e n t exergy required to recover the negative impacts due to waste emissions. A multi-objective genetic algorithm is employed to find optimal solutions. A case study is p r e s e n t e d and the effectiveness of the approach is d e m o n s t r a t e d for identifying a n u m b e r of P a r e t o optimal solutions for green building design.
06/01384 Computational analysis of performance and flow investigation on wells turbine for wave energy conversion D h a n a s e k a r a n , T. S. and Govardhan, M. Renewable Energy, 2005, 30, (14), 2129 2147. Wells turbine is a self-rectifying airflow turbine capable of converting p n e u m a t i c power of the periodically reversing air stream in oscillating water column into mechanical energy. This p a p e r reports the c o m p u t a t i o n a l analysis on performance and aerodynamics of Wells turbine with the N A C A 0021 constant chord blades. Studies have been m a d e at various flow coefficients covering the entire range of flow coefficients over which the turbine is operable. The p r e s e n t computational model can predict the performance and aerodynamics of the turbine quantitatively and qualitatively. The m o d e l also predicted the flow coefficient at which the turbine stalls, with reasonable accuracy.
Fuel and Energy Abstracts
May 2006
205