Abstract: A solar energy collector for cooking food or sterilizing liquids or articles is described, which may be fixed in place or portable. The device includes a heating (cooking or sterilization) chamber with a double-walled solar radiation concentrator with an outer transparent wall and an inner radiation absorptive wall, with the walls forming a space therebetween which is partially evacuated, means for retaining the food, liquid or articles within the chamber, an apertured casing attached to and surrounding the concentrator, and a support for the device. There may also be a radiation absorptive coating on the surface of the inner wall facing the evacuated space. Sunlight falling on the concentrator through the casing's aperture generates heat within the chamber to cook food or sterilze the liquid or articles.