The U.S. Department of Energy (DOE) recently released new estimates of the United States’ wind energy potential, which tripled previous estimates of the size of the nation's wind resources. The new study, which was carried out by the National Renewable Energy Laboratory (NREL) and AWS Truewind, finds that the contiguous 48 states have the potential to generate up to 37 million gigawatt hours annually. To put that in perspective, total U.S. electricity generation from all sources was roughly 4 million gigawatt hours in 2009. The estimates show the total energy yield that could be generated using current wind turbine technology on the nation's windy lands. (The estimates show what is possible, not what will actually be developed.)
Along with the state-by-state estimates of wind energy potential, NREL and AWS Truewind have developed wind resource maps for the United States and for the contiguous 48 states that show the predicted average wind speeds at an 80-meter height. The wind resource maps and estimates provide local, state, and national policymakers with accurate information about the nature of the wind resource in their areas and across the nation, helping them to make informed decisions about wind energy in their communities.
Why Has Wind Energy Potential Gone Up?
The new estimates reflect substantial advances in wind turbine technology that have occurred since the Department of Energy's last national wind resource assessments were conducted in 1993. For example, previous wind resource maps showed predicted average wind speeds at a height of 50 meters, which was the height of most wind turbine towers at the time. The new maps show predicted average wind speeds at an 80-meter height, the height of today's turbines. Because wind speed generally increases with height, turbines built on taller towers can capture more energy and generate more electricity. The new estimates also incorporate updated capacity factors, reflecting improvements in wind turbine design and performance.