Solar cookers:
A solar cooker, or solar oven, is a device which uses
the energy of direct sunlight to heat, cook
or pasteurize food or drink. Over the past many
decades, a number of designs of solar cooker have
been developed. The majority of solar cookers
presently in use are relatively cheap, low-tech devices.
Although solar cookers have been available for many
years, there is continuing interest in their performance
optimization.