This chapter summarizes the significance of renewable energy resources, their technological practices, positive and negative impacts. It also presents current energy scenario and future prospects. Projected demand of energy will increase drastically by 2030 as per findings of International Energy Agency (IEA). Renewable energy sources must be used at a massive scale, as a supplement to conventional energy sources, in order to fulfill the ever-increasing demand of energy. However, renewable forms of energy like solar, wind, hydropower, ocean, geothermal, and biofuels are not completely environment friendly, since they do have their impacts on biodiversity, soil, aquatic environments, marine life, air quality, and even human health. However, in comparison to the conventional sources of energy, their negative impacts on environment are quite meager, in most cases these sources of energy production proved to be carbon neutral and in some cases carbon negative. The chapter concludes that reliance on renewable forms of energy for power generation, will become indispensable for a sustainable future.