ABSTRACT
The revival of interest in the direct use of solar energy, which followed the 1973 oil crisis, has brought increased research and development activity in a number of areas. Some of these areas are discussed here, namely photocatalysis, photoelectrochemical cells, and photovoltaic devices. Solar cells, which are the photovoltaic devices that convert solar energy directly into electricity, are specially constructed semiconductor diodes. In 1973, the US National Science Foundation held a series of workshops with experts from industry, government, and the academic world to lay the foundation for a national photovoltaic program. The advantages of photovoltaic devices in field applications may be succinctly stated as three: Totally modular, largely maintenance free and without fuel requirement and friendly to the environment. The embryonic photovoltaic industry is entirely based on silicon with the largest proportion of the capacity still resting on single crystal silicon-based panels.
