Solar cooker with tracking-type bottom reflector: An experimental thermal performance evaluation of a new design

To fulfil the sustainable development goals (SDGs) of the United Nations, the solar cooker is one of the key devices. The objective of this work is to propose a new design of solar cooker equipped with internal reflectors and a tracking-type bottom parabolic reflector (TBPR) which may help in attainment of SDGs. The performance of cooker is determined using Cooker Opto-Thermal Ratio (COR) as a Thermal Performance Parameter (TPP) and glycerine as test load. Also, the effectiveness of the booster reflector is estimated using the Effective Concentration Ratio (ECR). First Figure of Merit (F₁) and overall cooker efficiency (η) are used to comment on performance of the proposed cooker. The real cooking tests are conducted for family of four people which describes usefulness of the proposed solar cooker. Experimental results depict the mean values of COR for the cooker with and without TBPR as 0.165 and 0.123, respectively. Also, the value of F₁ is found to be 0.119 while the value of the ECR for the cooker is 1.34. The overall cooker efficiencies for cooker with and without TBPR are estimated to be 10.7% and 12.5%, respectively. The results show that cooker with TBPR is able attain the intermediate temperatures ~ 140–150 °C. An economic analysis is done using two indicators, Levelized Cost of Heat (LCOH) and Cooking a Meal (LCCM) and there is a reduction of ~ 44% and 18% in the LCOH and LCCM respectively, for the cooker with TBPR compared to the cooker without TBPR.