This chapter presents an in-depth examination of major renewable energy technologies, including their installed capacity and energy supply in 2009 , the current state of market and technology development, their economic and financial feasibility in 2009 and in the near future,\ud
as well as major issues they may face relative to their sustainability\ud
or implementation. Renewable energy sources have been important for humankind since the beginning of civilization. For centuries, biomass has been used for heating, cooking, steam generation, and power production;\ud
solar energy has been used for heating and drying; geothermal energy has been used for hot water supplies; hydropower, for movement;\ud
and wind energy, for pumping and irrigation. For many decades renewable energy sources have also been used to produce electricity or\ud
other modern energy carriers