
Renewable energy is energy that is collected from renewable resources, which are naturally replenished on a human timescale, such as sunlight, wind, rain, tides, waves, and geothermal heat. Renewable energy often provides energy in four important areas: electricity generation, air and water heating/cooling, transportation, and rural (off-grid) energy services. Renewable energy is generated from natural resources that include wave, wind, biomass, solar, hydro, geothermal, and tidal power. National governments and corporate enterprises are making heavy investments to develop and enhance clean renewable energy sources. These resources produce large quantities of energy and avoid greenhouse gases that contribute to the climate change.