Renewable energy comes from natural resources like sunlight, wind, rain, tides, and geothermal heat that replenish naturally. Solar panels capture energy from the sun to produce electricity, while wind turbines harness wind power; rain and tidal action also have potential to generate energy. Geothermal energy captures heat from within the earth to produce different forms of energy, while renewable resources currently supply less than 35% of the world's demands but are expected to grow with increasing global energy needs.