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Energy, exergy, and Second Law performance criteria
Lior, Noam; Zhang, Na - In: Energy 32 (2007) 4, pp. 281-296
and use of energy and exergy based performance criteria, and of the Second Law efficiency, with an aim at the advancement …Performance criteria, such as efficiencies and coefficients of performance, for energy systems, are commonly used but …
Persistent link: https://www.econbiz.de/10010807607
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Measuring efficiency and productivity change in power electric generation management companies by using data envelopment analysis: A case study
Fallahi, Alireza; Ebrahimi, Reza; Ghaderi, S.F. - In: Energy 36 (2011) 11, pp. 6398-6405
This paper provides an empirical analysis of the determinants of energy efficiency in 32 power electric generation … relative technical efficiency and productivity change of these companies. In order to verify the stability of our DEA model and … technical efficiency of companies decreased during the study period. Nearly half of the companies (14) are below this average …
Persistent link: https://www.econbiz.de/10010810971
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A non-parametric Data Envelopment Analysis approach for improving energy efficiency of grape production
Khoshroo, Alireza; Mulwa, Richard; Emrouznejad, Ali; … - In: Energy 63 (2013) C, pp. 189-194
Grape is one of the world's largest fruit crops with approximately 67.5 million tonnes produced each year and energy is an important element in modern grape productions as it heavily depends on fossil and other energy resources. Efficient use of these energies is a necessary step toward reducing...
Persistent link: https://www.econbiz.de/10010811362
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Study on energy efficiency in corn production of Iran
Banaeian, Narges; Zangeneh, Morteza - In: Energy 36 (2011) 8, pp. 5394-5402
energy efficiency by Data Envelopment Analysis (DEA) in corn production of Iran during a seven years period. Results … results showed that average energy use efficiency, energy productivity, specific energy and net energy gain in the studied … that average energy efficiency score was 90.26%. There is impermanent trend in growth of energy efficiency in corn …
Persistent link: https://www.econbiz.de/10011053940
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Environmental benchmarking of wind farms according to their operational performance
Iribarren, Diego; Martín-Gamboa, Mario; Dufour, Javier - In: Energy 61 (2013) C, pp. 589-597
facilities. In this work, the LCA + DEA methodology was used to benchmark the operational and environmental performance of a …, potential relationships between efficiency and annual power generation, location or average wind speed were discussed. …
Persistent link: https://www.econbiz.de/10011055453
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Using compressor discharge air bypass to enhance power generation of a steam-injected gas turbine for combined heat and power
Kang, Do Won; Jang, Hyuck Jun; Kim, Tong Seop - In: Energy 76 (2014) C, pp. 390-399
In gas turbine combined heat and power systems, steam injection is a good way to cope with seasonal variations in electricity and heat demands. However, even though thermal energy demand decreases considerably in cooling seasons, the surplus exhaust heat cannot be fully utilized for steam...
Persistent link: https://www.econbiz.de/10010939821
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Numerical investigation of impeller trimming effect on performance of an axial flow fan
Li, Chunxi; Li, Xinying; Li, Pengmin; Ye, Xuemin - In: Energy 75 (2014) C, pp. 534-548
To study the performance variations of an axial fan after impeller trimming, numerical simulations are executed under …. The effects of trimming quantity and tip clearance on flow field and performance of the axial fan are investigated, and … before and after impeller trimming. The simulated results show that the performance curves after impeller trimming tend to …
Persistent link: https://www.econbiz.de/10010931382
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Combustion, performance and emission characteristics of direct injection diesel engine fueled by Jatropha hydrogen peroxide emulsion
Nguyen, Kim-Bao; Dan, Tomohisa; Asano, Ichiro - In: Energy 74 (2014) C, pp. 301-308
Recently, Jatropha, a fast growing tropical plant, has caught the attention of researchers because the oil produced from Jatropha is a non-edible. However, worse emissions, when using raw Jatropha oil in diesel engines, have been reported in the literature due to its higher viscosity and lower...
Persistent link: https://www.econbiz.de/10010931391
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Numerical investigation of blade tip grooving effect on performance and dynamics of an axial flow fan
Ye, Xuemin; Li, Pengmin; Li, Chunxi; Ding, Xueliang - In: Energy 82 (2015) C, pp. 556-569
Appropriate changes to the blade tip structure can effectively improve fan performance. The performance of the OB-84 …, both the total pressure rise and shaft power of the fan decrease, but the efficiency improves distinctly; the grooved blade … efficiency with an increase of 1.07% at design volume flow rate, and case 7 obtains the lowest shaft power compared with the …
Persistent link: https://www.econbiz.de/10011209474
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Thermoelectric mini cooler coupled with micro thermosiphon for CPU cooling system
Liu, Di; Zhao, Fu-Yun; Yang, Hong-Xing; Tang, Guang-Fa - In: Energy 83 (2015) C, pp. 29-36
between the maximal COP (Coefficient of Performance) and Qc with the figure of merit. Full-scale experiments have been … number on the performance of the cooling system. Experimental results indicated that the cooling production increases with … performance of this cooling system could be enhanced when the total dimension of thermoelectric module matched well with the …
Persistent link: https://www.econbiz.de/10011264368