This text book Renewable energy is very much useful for the undergraduate students who opted renewable energy as elective and for solar energy in all universities of Andhra Pradesh and other Universities. Now a day renewable energy is one of the biggest sources to get relief from the pollution arises by conventional energy sources. This book covers solar energy, wind energy, ocean energy, hydrogen energy and biomass energy along with different energy sources available in India and throughout the world. All suggestions are heart fully welcome for the further improvement of the book.