Theoretical and experimental analysis of box-type solar cooker with sensible heat storage

The thermal performance of the current box-type solar cooker is limited, and no provision for evening cooking, which could increase its dependability and attract more consumers. The thermal performance and evening cooking capabilities can be enhanced by employing the waste marble pieces as integrated or portable heat storage material. Also, suggested using a matt black coated aluminium sheet placed additionally below the glass cover to reduce the top heat losses. In this work, two arrangements were proposed: (I) a cooking load with heat storage but no aluminum sheet, and (II) a cooking load with both aluminum sheet and heat storage. The scope of improvement is evaluated using the COMSOL Multiphysics 6.0 software tool and experimental testing conducted in an outdoor environment. The cooking times for arrangements I and II are evaluated experimentally as 154-155 min and 175-176 min respectively, corresponding cooking power are measured as 56.62 W and 48.21 W, respectively and the corresponding thermal efficiencies are 25.79 % and 31.19 %, respectively. The optimal time for heating various weights of marble pieces is investigated using an aluminum sheet cover since the thermal performance and temperature availability till late evening are relatively low. The proposed solar cooker has a payback period of 1.24 years. It is concluded that installing a single solar cooker for two members of a family reduces a total of 148.3 kg of carbon dioxide annually.