With the current increasing population, it is becoming huge necessity for using the sustainable energy. It focuses on the future needs. The objective behind the Sustainable energy is to meet the present need without compromise for the future generation on the energy usage. Renewable energy is the type of sustainable energy which is naturally occurring and easily replenished without getting depleted. It is inexhaustible. Renewable energy and energy efficiency are the two main key components for the sustainable energy. All renewable energy sources like solar, wind, geothermal, hydropower and ocean energy are sustainable as they are stable and available in plenty. Bioenergy is also a kind of sustainable energy which is the energy generated from the biological masses such as straw, corns, manures and other agricultural plants. For the sustainability of energy we can go for energy conservation and its efficiency. Sustainable energy is not only inexhaustible but also causes no damage to the environment as there is no release of pollutants.