Solar energy is created by sunshine and is a non-depleting renewable form of energy that is not environmentally harmful. The amount of solar energy that enters the earth every hour is sufficient to supply all of the energy needed for a year.The power generated by a single photovoltaic cell is typically only about two watts. Since the intensity of solar radiation is already low, most modern photovoltaic cells only have an energy efficiency of 15 to 20 percent, and in order to generate even modest amounts of power, large and expensive assemblies of these cells are needed. The most plentiful energy source on our planet is the sun's rays.In fact, the sun provides more energy to the earth in an hour than it does in a year