Design And Performance Evaluation Of A Parabolic Solar Cooker

Abstract

The design, construction and performance test of a parabolic solar cooker for domestic use are presented. The simple experimental parabolic solar cooker, made of locally available materials, consists of a parabolic dish of thickness 0.3mm, adjustable mechanism, pot, pot holder, base support and a reflecting glass surface. The concave surface of the dish was lagged with reflective glasses which serve as a reflecting surface. Commercially available (3mm) thick glass is used as glazing material. The absorber plate, cylindrical in shape, 0.8mm thickness iron sheet was painted black. Provision is made for one cooking pot, capable of holding up to 5 litres of water. The fully constructed parabolic solar cooker was tested under the meteorological conditions of Federal University of Technology, Owerri (FUTO). Thermometers were inserted at strategic points to measure the ambient and water temperatures while a pyranometer was used to measure the solar radiations for the period of experimentation. The system was manually adjusted to align with the direction of the sun. It was able to heat 5 litres of water from a temperature of 27℃ to 98℃ within 2 hours and also, effectively cooked 2kg of dry rice within 5hrs.The results obtained were deployed in the calculation of the two figures of merit (F1 & F2), efficiency (η), cooking and standard cooking power(Ps) as 0.12, 0.64, 15%, 75W and 80.45W respectively. The total cost of the constructed parabolic solar cooker was eighty thousand naira (N80, 000). The result shows that the device can be of great assistance in the fight against global warming caused by the emission of carbon dioxide into the atmosphere through the use of fossil fuels in cooking. It can also, save considerable amount of resources (money and energy), frees children from the daily and dangerous task of collecting firewood from the forest, conserve our environment and reduce exposure of women to cooking smoke when used in homes as a backup device for cooking purposes.

Keywords: Solar Cooker, Heating, Thermometer, Pyranometer and Efficiency.