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Wind PowerEarth and Environment
BACKGROUND REPORT ADDITIONAL FEATURES
Sources of Energy in the United States Updated: May 23, 2007
1975 1985 1995 2000 2004 2005 2006
Coal 16.73% 22.82% 22.03% 22.82% 22.42% 22.67% 22.59%
Natural Gas 26.35% 23.29% 24.98% 24.17% 22.95% 22.77% 22.58%
Petroleum 43.23% 40.38% 37.89% 38.80% 40.51% 40.53% 40.36%
Nuclear Electric 2.51% 5.32% 7.76% 7.94% 8.21% 8.12% 8.24%
Hydroelectric 4.17% 3.88% 3.51% 2.84% 2.68% 2.69% 2.90%
Biomass* 1.98% 3.88% 3.31% 2.94% 2.80% 2.85% 2.99%
Geothermal^ 0.09% 0.26% 0.32% 0.32% 0.34% 0.34% 0.35%
Solar N/A 0.00% 0.08% 0.07% 0.06% 0.07% 0.07%
Wind N/A 0.00% 0.04% 0.06% 0.14% 0.18% 0.26%

Source: Energy Information Administration, April 2007 Monthly Review

*-- Biomass resources exist in three forms: wood, waste and plant-derived alcohol fuels. Wood chips or harvested wood can be burned to produce energy. Waste energy comes from industrial waste, landfill gases or plant and animal waste. Ethanol is the main form of alcohol fuel.

^-- Geothermal energy comes from natural steam or hot water reservoirs in the Earth's crust. Steam turbines produce energy for low-to-moderate demand use.


  Main: Wind Power
REPORTS
  Wind Power Basics
  Land- vs. Sea-based Wind Farms
  Assessing the Threat to Birds
RESOURCES
  Animation: Wind Turbine
  Chart: Sources of Energy
FOR STUDENTS AND TEACHERS
  Lesson Plan
  Alternative Energy