Renewable energy is energy derived from renewable resources that are renewed naturally on a human timeline. It includes sources such as sunlight, wind, rain, tides, waves, and geothermal heat. The reliable use of these resources has the least environmental effect, produces the least secondary waste, and is sustainable in terms of present and future economic and social demands. Renewable energy technologies provide a tremendous potential to reduce greenhouse gas emissions and global warming by substituting traditional energy sources. A lot of countries now rely on renewable energy for more than 20% of their energy supply, with some generating more than half of their power from renewables.