Renewable energy is energy which comes from natural resources such as sunlight, wind, rain, tides, and geothermal heat, which are renewable (naturally replenished). Renewable energy can be used again and again, and will never run out. It primarily consists of following subsectors: 1 Solar Solar is the alternative and renewable energy source which involves utilizing the light emitted by Sun and converting it into electrical current and thermal energy. 2 Wind Wind energy is energy collected from motion caused by heavy winds to generate mechanical or electrical energy that can be used for Power or any other similar purpose 3 Biomass Biological matter, such as wood, agricultural crops or wastes, when used as a source of fuel or energy. 4 Hydro Hydro energy is energy that is taken from water and converted to electricity 5 Tidal Tidal energy is the energy produced by utilizing the flow of tides in the ocean. 6 Ethanol Ethanol is made by fermentation of sugar and starch crops and is used as a natural, renewable fuel or as blended fuel with gasoline. 7 Biodiesel Biodiesel is a renewable fuel for diesel engines derived from natural oils like soybean oil , animal fat or algae oils 8 Geo Thermal Geothermal energy is power generated from natural steam, hot water, hot rocks, or lava in the Earth's crust. In general, geothermal power is produced by pumping water into cracks in the Earth's crust and then conveying the heated water or steam back to the surface so that its heat can be extracted through a heat exchanger, or its pressure can be used to drive turbines.