Types of Renewable Electricity

• Wind turbines are a clean form of renewable electricity production. Paul Edmondson/Photodisc/Getty Images

  Natural resources such as oil, coal and natural gas have a limited lifespan. The constant demand for power and electricity has placed a strain upon these dwindling resources, while pollution has further promoted the drive for cleaner energy. The development of renewable energy sources offers a potential solution to these key problems. A combination of renewable electricity production methods could one day replace the need for non-renewable resources altogether.

Hydropower

• The kinetic energy contained within moving river water is used to produce electricity. This renewable form of energy production is known as hydropower. Hydropower systems range from massive dams built across entire rivers to small-scale hydroelectric turbines placed directly in the river flow. According to the Pollution Issues website, hydropower is the leading renewable energy source in the United States, generating approximately nine percent of the nation's electricity.

Tidal Power

• Tidal power, or ocean energy, can be used to produce electricity. Like hydropower, tidal power harnesses the movement of water, in this case coastal water, to rotate turbines. Gates and turbines are installed along a dam that goes across a tidal bay or an estuary, says the New Energy Portal website. The gates are opened when the tide is in and then closed when the tide starts to go out, channeling the receding water past the turbines.

Geothermal

• According to the Learn About Energy website, geothermal energy is produced from naturally occurring steam and hot water from under the Earth's surface. Steam is brought towards the Earth's surface where it is used to power turbines. These turbines are then used to power electrical generators. Geothermal energy production is clean and reliable, but it is limited to specific sites where hot water and steam occur naturally.

Wind

• The kinetic energy of the wind can be harnessed using wind turbines. Propeller-like blades attached to a drive shaft are set in motion when the wind blows. The spinning drive shaft then turns a generator, producing electricity. This type of energy production is obviously ineffective when there is no wind, but when placed in an exposed, wind-swept area the production level is fairly constant. In 2009, wind power accounted for about 1.8 percent of total U.S. electricity generation, says the U.S. Energy Information Administration Energy Kids website.

Solar

• Solar power plants use photovoltaic cells to convert sunlight directly into electricity. These cells also can be used to generate electricity for small-scale, stand-alone units such as houses, street lamps and earth-orbiting satellites. Initial set-up costs are high, but the subsequent energy supply is clean and easy to maintain.

Biomass

• Biomass energy can be used to provide renewable electricity, heat and transport fuels, says the Institution of Mechanical Engineers website. Plant material is the basic source of biomass energy, whether in the form of organic waste, agricultural residue or energy crops grown specifically for the task. This material can be burned to produce heat or power directly, or converted into a combustible liquid or gas for use in electrical power stations.