Renewable energy sources are sources of energy that are theoretically inexhaustible and not derived from fossil fuels or nuclear sources. Examples of renewable energy sources are wind, the sun, water, geothermal and biomass.
In the United States, the availability and cost-effectiveness of renewable energy sources can vary widely. Many of these resources, such as water and wind, may seem inexpensive, but there can be significant costs in harnessing these resources, collecting the energy and transporting it for use. In order for water to be used for energy purposes, a dam must be constructed, electric generators must be installed and transmission lines must be built to take advantage of the energy. It may also be important to understand that even these resources can cause environmental issues. Dams can effect migration of fish native to the river where a dam is built, for example.
Renewable energy sources are very different from non-renewable resources. Oil, coal and natural gas are examples of non renewable resources. Deposits of these fuels cannot be replaced once they are used. Instead, people must find new deposits to continue creating energy from these sources. Both renewable and non renewable energy sources have the capability of powering vehicles, generating electricity and providing cooling and heating.