ABSTRACT
Photovoltaic solar energy is the direct conversion of sunlight to electricity. Photovoltaics will suit any small need for lights; for fence charging as has been done for many years; for radio communications; or in some instances, for small dwellings. The traditional alternative to photovoltaics is the use of a generator powered by a gasoline or diesel engine. Perhaps the most practical use for photovoltaics other than communications and small-lighting generation is water pumping. The sizing constraint with photovoltaics to accommodate for cloudy weather or for climate using known solar insolation is possible with data which has been collected by the US Department of Energy for many years. A well-made solar pump will take into consideration the various amounts of sun energy striking the earth that is referred to as insolation, and will match its performance to the available insolation. There are various solar pumping devices on the market.
