What Is Renewable Energy?
Renewable energy sources can be replenished in a short period of time. The five renewable sources used most often are:

• Biomass — including wood and wood waste, municipal solid waste, landfill gas, biogas, ethanol and biodiesel
• Water (hydropower)
• Geothermal
• Wind
• Solar

What Role Does Renewable Energy Play in the United States?
The use of renewable energy is not new. More than 150 years ago, wood, which is one form of biomass, supplied up to 90% of our energy needs. As the use of coal, petroleum and natural gas expanded, the United States became less reliant on wood as an energy source. Today, we are looking again at renewable sources to find new ways to use them to help meet our energy needs.

In 2009, consumption of renewable sources in the United States totaled 7.4 quadrillion Btu — 1 quadrillion is the number 1 followed by 15 zeros — or about 7% of all energy used nationally.

The Role of Renewable Energy Consumption in the Nation's Energy Supply
About 8% of U.S. electricity was generated from renewable sources in 2009, with over half going towards the production of electricity. The next largest use of renewable energy is the production of heat and steam for industrial purposes. Renewable fuels, such as ethanol, are also used for transportation and to provide heat for homes and businesses.

Renewable energy plays an important role in the supply of energy. When renewable energy sources are used, the demand for fossil fuels is reduced. Unlike fossil fuels, non-biomass renewable sources of energy (hydropower, geothermal, wind, and solar) do not directly emit greenhouse gases or other pollutants such as sulfur dioxide, mercury and carbon monoxide.

Facts about Renewables
As the impact of fossil fuels on our environment becomes ever more stark, renewable energy - with its non-polluting qualities and infinite capacity - is just what we need to save our fragile planet. Thanks to the work of engineers and scientists we are able to harness the renewable energy available to us and make it useful. Prepare yourself for our top 10 must-know renewable energy facts...

1. There are five main forms of renewable energy: solar, wind, water, biofuel and geothermal (heat from the earth).
2. If it could be properly harnessed, enough sunlight falls on the earth in just one hour to meet world energy demands for a whole year!
3. Ever the innovator, Albert Einstein won the Nobel Prize in Physics 1921 for his ground-breaking experiments with solar power and photovoltaics.
4. The geothermal energy from the core of the Earth is closer to the surface in some areas than in others. Where hot underground steam or water can be tapped and brought to the surface it can be used to generate electricity.
5. A world record was set in 1990 when a solar-powered aircraft flew across the USA in 21 stages, using no fuel at all.
6. One wind turbine can produce enough electricity to power up to 300 homes.
7. The largest wind turbine in the world, soon to be located in the North Sea, has blades almost the length of a football field.
8. An average wind speed of just 14mph is needed to convert wind energy into electricity; that shouldn't be too hard to come by in breezy Britain!
9. Water is the most commonly used renewable energy resource, providing enough power to meet the needs of 28.3 million people.
10. Those clever old Romans not only gave us the modern drainage system and many of our roads, they were also among the first to use geothermal energy to heat houses.