Parabolic Solar cooker Construction-2011
Although these types of solar cookers can cook as well as a conventional oven, they are difficult to construct. Parabolic cookers reach high temperatures and cook quickly, but require frequent adjustment and supervision for safe operation. Several hundred thousand exist, mainly in China. They are especially useful for large-scale institutional cooking.
Parabolic reflectors that have their centers of mass coincident with their focal points are useful. They can be easily turned, to follow the sun's motions in the sky, rotating about an axis that passes through the focus. The cooking pot therefore stays stationary. If the parabolic is axially symmetrical and is made of material of uniform thickness, this condition occurs if the depth of the parabolic is 1.8478 times its focal length.
This project was also covered by ETECH (Express TV) last year.