Keywords: energy efficiency, exergy efficiency, solar box-cooker
Energy and exergy efficiencies of a solar box-cooker
A simple and low-cost box-type solar cooker (SBC) was designed and tested. The energy and exergy efficiencies of the SBC were experimentally evaluated. The energy output of the SBC ranges from 2.1 to 61.7 kJ, whereas the exergy output ranges from 0.4 to 6.2 kJ during the same time interval. The average daily energy and exergy outputs of the SBC are 21.6 and 2.5 kJ, respectively. A linear regression is developed to find the relationships between the energy/exergy outputs, and the efficiencies and temperature difference. The energy efficiency of the SBC varies between 1.3 and 55.6%, while the exergy efficiency varies between 0.3 and 6% during the same period. The average daily energy and exergy efficiencies of the SBC are 18.3 and 2.2%, respectively.