Solar photovoltaic cells have been called the ultimate energy technology, environmentally benign and without moving parts, solar cells directly convert sunlight into electricity. Photovoltaic energy conversion is fundamentally different from all other forms of electricity generation. Without turbines, generators or other mechanical equipment, it more closely resembles photosynthesis, the biochemical process that forms the energy basis of life on earth. A product of mid-twentieth century solid-state physics, photovoltaics has attracted a wide range of supporters: back-to-nature homesteaders, environmentalists, politicians, and businessmen. Increasingly, photovoltaics is a world of big business, with oil companies contributing a sizable share of the nearly half-billion dollars invested worldwide in 1982. Although research and development still form much of the solar cell industry, practical use of the technology is growing rapidly. Photovoltaic technology, cost reduction, the photovoltaics industry, government programs and international competition, applications of photovoltaics technology, solar power stations, and the future of solar power are discussed in separate sections. (Author/JN)