| The over-consumption of fossil fuels has caused a growing energy crises and the continuous reliance on fossil fuels and wood as sources of power has contributed to global warming, extreme health hazards in many places around the world, and the destruction of forests and other precious natural resources. An alternate source of clean, abundant, accessible and renewable energy, often overlooked, is the sun.; The sun is a very large and effective source of energy. The energy provided by the sun can be easily used for domestic, industrial and agricultural applications. The use of solar energy for cooking is one of the important applications of solar energy especially in developing countries where the firewood or oil is used for cooking.; Different models of solar cookers have been built in the past. However, the most efficient and in the same time the safest one is the hot-box. A hot-box gathers energy with the use of the green house effect. By raising the temperature inside the box, it is possible to cook food or make other uses of the heat energy.; In this work, a hot-box solar oven has been designed and constructed. The oven consists of an isolate hot box with four mirror reflectors. The isolation of the box prevents the energy loss from the walls. To increase the efficiency of the oven, the great heat storage capacity of rocks was considered. Heat storage capacity of different rocks was measured and dolerite was chosen to be placed as the bed rock inside the oven. A numerical model has also been developed for heat analysis in the oven. The oven was tested under different working conditions for over two years. It was found that using rocks in the bed of oven increases the efficiency of the oven. |
