Colorado Reader 09/2014 | Seite 6

More Renewable Energy Sources Solar, wind and hydropower are familiar sources of renewable energy, but the earth offers us even more ways to generate electricity from its renewable resources. Geothermal power plants work by tapping into steam or hot water reservoirs underground. The heat is used to drive a generator that produces electricity. Geothermal energy uses the Earth’s internal heat to help heat and cool buildings and make electricity. It’s the same energy that causes volcanoes and geysers to erupt. Biomass energy uses natural materials like wood, paper, plants and even garbage to make electricity. Chemical energy is released from bio- mass as heat when it is burned. The wood you burn in a fireplace or campfire is a biomass fuel. Wood and waste materials made from wood and garbage are burned to produce steam for making electricity. A geothermal system for a home or building uses pipes buried four to six feet underground, where the temperature remains about 50-55 degrees all year long. A geothermal system pumps a liquid through the pipes to absorb the warmth and bring it back indoors. In the summer, it works in reverse to cool the temperature of hot buildings. Burning biomass is not the only way to release its energy. Biomass can be converted to other useable forms of energy like methane gas, or fuels like ethanol and biodiesel that can power cars and trucks. 6 www.growingyourfuture.com