The biggest challenge in solar cooking is to be able to cook after hours or in cloudy conditions. Solar cookers and ovens around the world focus on solar cooking while the sun is shining and have reached a high level of efficiency over the years.
Experiments with molten salts, gravel and all sorts of heat retention materials have been tested, but with very little success.
Solar Geysers and electrical elements
The convenience of added electricity changed the solar geyser industry forever. Solar box cookers are the only solar cooker type suitable for the installation of backup electricity.
Sungenius added a specially designed low wattage electrical element to all solar box cookers. It is therefore now possible to cook a meal from solar power in all weather conditions, day and night.