3.3.4.4 SOLAR COOKERS AND OVENS

Solar cookers and ovens (fig. 3.13) have been used for over 200 years to cook, bake and purify drinking water.

Source CRES
Figure 3.13 A solar cooking device

There are three basic types of solar oven, namely box, parabolic reflector and multi-reflector. The solar box, which absorbs solar radiation and releases it to the food, is the least expensive and fastest to make - as low as a few dollars and using mostly recycled materials that can be assembled in a few hours - and achieves temperatures as high as 149°C. They are excellent for the slow boiling of foods, such as stews, soups and cereals. The base of the solar oven is a well-insulated wooden box, which attracts, captures, increases and maintains the sun's natural heat.

3.3.4.5 MECHANICAL POWER

One of the major issues of interest nowadays is the conversion of solar energy into mechanical power. Where a small scale direct drive is desired, this may be done by steam engines supplied with steam from a large cylindrical parabolic concentrator, but this is likely to be expensive. Larger scale projects will normally involve electricity generation (see below).