Renewable Energy 

What is Renewable Energy? What Role Does Renewable Energy Play in the United States? Why Don't We Use More Renewable Energy? How Do We Measure Renewable Energy? Recent Statistics Renewable Slide Show - watch and listen

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 and 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. Five generations (125 years) ago, wood, which is one form of biomass, supplied up to 90 percent of our energy needs. Due to the convenience and low prices of fossil fuels, wood use has fallen in the United States.

Overall consumption from renewable sources in the United States totaled 6.8 quads (quadrillion Btu) in 2007, or about 7 percent of all energy used nationally. Consumption from renewable sources was at its highest point in 1997, at about 7.2 quads.

The Role of Renewable Energy Consumption
in the Nation's Energy Supply, 2007

Over half of renewable energy goes to producing electricity. The next largest use 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. 

Why Don’t We Use More Renewable Energy?

In the past, renewable energy has generally been more expensive to use than fossil fuels. Plus, renewable resources are often located remote areas and it is expensive to build powerlines to the cities where they are needed. The use of renewable sources is also limited by the fact that they are not always available (for example, cloudy days reduce solar energy, calm days mean no wind blows to drive wind turbines, droughts reduce water availability to produce hydroelectricity).

The production and use of renewable fuels has grown more quickly in recent years due to higher prices for oil and natural gas, and a number of State and Federal Government incentives, including the Energy Policy Acts of 2002 and 2005.  The use of renewable fuels is expected to continue to grow over the next 30 years, although we will still rely on non-renewable fuels to meet most of our energy needs.

How Do We Measure Renewable Energy?

Each of the energy sources we use is measured, purchased, and sold in a different form. Many units of measurement are used to measure the energy we use.  Learn more about converting energy units in the Units of Measurement section.

Last Revised: August 2008
Sources: Energy Information Administration, Energy in Brief, How Much Renewable Energy Do We Use?, May 2008.
Energy Information Administration, Annual Energy Outlook 2008, Tables A2 and A16, June 2008.