The development of clean energy resources as alternatives to oiI has become one of the most important challenges for modern science and technology. The obvious motivation for these efforts is to reduce the air polIution resulting from the mass consumption of fossil fuels and to protect the ecological cycles of the biosystems on Earth. Analyses of future energy usage envision that the energy structure in the 21st century will be characterized as a "Best Mix Age" involving different renewable energy forms. Among the wide variety of renewable energy projects in progress, photo- voltaics is the...