Most of the world's energy is derived from the sun, whether it be stored fossilfuel deposits, wind power, water power or the conversion of agricultural organicproducts into useful mechanical power through combustion or through thefeeding of horses, other animals and humans. Tidal power is a minor exception,but even this is based upon planetary motion involving the sun and moon. Nuclearpower is perhaps the one major exception.

This paper discusses the history of the use of solar power for various applications and the burgeoning interest in its use during the energy crises of the 1970s.