Solar energy proves to be a promising alternative energy source in providing low grade heat required in many com- mercial and industrial applications, especially in countries where this source is abundantly available. During past three decades, theoretical and experimental investigations of various solar thermal systems have received considerable attention of researchers around the world with objectives of reducing dependence on the energy sources derived from fossil fuels and minimizing their adverse environmental impacts. The most widely studied solar thermal systems include solar water and air heaters, box and focussing type solar cookers, solar dryers, and solar stills. It can be noticed that the thermal test procedures for standardiza- tion of selective solar equipments namely, solar domestic water heaters, solar cookers, etc., have already been devel- oped and adopted in many countries including India