- Geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity.Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth.
- Biomass energy: Biomass is organic material made microorganisms. Biomass contains stored energy from the sun. Plants absorb the sun's energy in a process called photosynthesis. The chemical energy in plants gets passed on to animals and people that eat them.
- Wind energy: Wind is simply air in motion caused by uneven heating on the surface of the earth. Because the earths surface is made of many different things it absorbs heat at different rates.
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"Renewable". EIA energy kids. <http://www.eia.gov/kids/energy.cfm?page=renewable_home-basics>