Solar air Heater

There are three main methods of active cooling. First of all, the use of electric compressors, which are now standard cooling device in Europe. Secondly, the use of absorption air conditioners powered by using thermal energy. There is a third possibility for air conditioning - using evaporative cooling. All systems can operate on solar energy.

Solar collector, which heats the air, can serve as a cheap source of heat for drying crops - grains, fruits or vegetables.

Using simple and cheap solar collectors for heating the air used to dry the crop is promising to reduce the huge crop losses in developing countries.