Experimental determination of energy and exergy efficiency of the solar parabolic-cooker

A simply designed and the low-cost parabolic-type solar cooker (SPC) was made and tested. The energy end exergy efficiencies of the cooker were experimentally evaluated. The experimental time period was from 10:00 to 14:00 solar time. During this period, it was found that the daily average temperature of water in the SPC was 333 K and the daily average difference between the temperature of water in the cooking pot and the ambient air temperature was 31.6 K. The energy output of the SPC varied between 20.9 and 78.1 W, whereas its exergy output was in the range 2.9–6.6 W. The energy and exergy efficiencies of the SPC were in the range, respectively, 2.8–15.7% and 0.4–1.25%. 2004 Elsevier Ltd. All rights reserved