Passive Solar System to Store Heat for Cooking
Abstract
A passive solar heat storage system for cooking is constructed and tested. The system is designed to convert excess electricity to high temperature heat (about 250 degrees) and store it for cooking at times when needed. When electrical batteries are full, the PV power is directed to the heat storage. Wind and hydro turbines can provide excess electricity in the same manner, through a diversion controller for a battery. For the AC case, the heat storage can replace dump loads which are used to provide a constant load for generators. The system is based on oil as a heat transfer and storage media. Care has been taken to make it as simple as possible, in order to be produced and maintained in a rural African setting. The flow is gravity driven, and without sensors and pumps a mechanical thermostat valve controls the storage temperature. The prototype system has been tested and is ready for field tests. Key-words: solar heat storage, solar cooking, heat batteries, PV to heat