ABSTRACT
The photovoltaic effect, the direct conversion of light energy into electricity by solar cells, was first observed in 1839, but until the mid-1950’s it remained largely a laboratory curiosity with relatively few practical uses. Following the 1973 oil crisis, interest in photovoltaics as a terrestrial source of power increased greatly and many countries, including several developing countries, instituted photovoltaic research, development and demonstration programmes. Photovoltaic arrays for space satellites are assembled to very exacting standards, as low weight and high reliability are of the utmost importance. Photovoltaic systems provide a convenient and cost-effective solution for the provision of relatively small amounts of power needed for a wide range of applications. Photovoltaic refrigerators have been under development for many years and several types are now available commercially.
