PV, the technology which converts sunlight directly into electricity, is among the fastest growing segments of the renewable energy industry. It is already well established in many countries including India, and looks set to become one of the key technologies of the 21st century. Some of the factors driving the growth of this segment are: concerns towards carbon emissions, energy security and the rising prices of fossil fuels.
Traditional solar cells are made from silicon, and are generally the most efficient. Thin-film solar cells made from amorphous silicon or non-silicon materials such as cadmium telluride are the second-generation solar cells, and are gaining a greater share in overall installations.
Third-generation solar cells use a variety of new materials and nanotechnology etc. for designing high efficiency PV materials. These systems are expected to rapidly become cost effective for use by utilities and industry.