Insulated Solar Electric Cooker (ISEC)

This project presents the design and fabrication of an insulated solar electric cooker (ISEC) which makes use of a 100 Ah/12 V battery for use during off-sunshine hours. A 30 A solar charge controller regulates how the battery is being charged by the 180 W solar panel. The panel could charge the battery to full capacity in 7 hours of uninterrupted sunlight. The deficiency of sunlight during some days, especially rainy season can delay charging and extend it to longer hours and even days. The system makes use of Nichrome 80 (Ni 80%, Cr 20%) wire of diameter 0.32 mm as heating element. Coiled in three different lengths, the element draws on average 20.4 A to run it. The cooking chamber was insulated with fiberglass to reduce loss of heat to the surrounding. The tests carried out show that the system is 33.1% efficient. The cooker was able to heat 1 liter of water from 31 °C to 92 °C in 50 minutes, with limited sunlight. The system is a good alternative to conventional cooking methods that depend solely on fossil fuels, especially for rural areas where the use of fuel wood is still prevalent. The findings from this study may be the solution to developing a better technology that utilizes only sunlight and is affordable to the poorest households, especially in Nigeria.