Renewable energy refers to energy that originates from natural processes which are continuously replenished. It includes a wide range of sources, including solar, wind, geothermal, water and biomass. The main task that renewable energy carries out is to generate electricity, supply heat, and power its own transportation system. All of these are major points in which it actively reduces greenhouse gas emissions. There's not a whole lot of common ground in these physical methods for enabling renewables to contribute anywhere from 5-20% of a society's power supply. The features of renewable energy technologies vary by type but generally include advanced materials, increased efficiency and smart grid interconnection. It is for heating and cooling, the generation of electricity in houses or industry. Uses cover a wide range yet overall it is one that starts at home and extends through an entire enterprise building. In many fields renewables can be thoroughly integrated with the existing infrastructures, to create a future energy system that is both sustainable and healthy.