Solar PV (photovoltaic) systems generate electricity when sunlight falls on solar panels which are normally made of crystalline silicon and mounted on the roof of the home or other building. Although a great deal of energy is consumed in the manufacture of PV systems, one installed they should continue to produce virtually free electricity for up to 20 years. - Description added by: www.microchap.info

Renewable and alternative energy sources are set to play an increasingly important role in providing the electricity, heat, cooling and fuels that society needs. There is a wide range of energy sources such as solar (both photovoltaic and solar thermal), wind, bio-fuels and biomass, hydro-electric, geothermal and heat pumps. - Description added by: David Lockie

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