Wind turbines capture energy and produce electricity using long, rotating blades that drive a generator. Offshore wind resources tend to be stronger and more consistent than onshore wind. There are currently no offshore wind turbines in the United States; though offshore leases have been granted and some projects are nearing construction. The US Department of Energy estimates more than 4,000 GW of energy could be generated in state and federal waters along the coasts and in the Great Lakes. For more information on offshore wind energy technologies, visit the Bureau of Ocean Energy Management or the U.S. Department of Energy's Office of Energy Efficiency and Renewable Energy websites.
While all renewable energy systems impact natural, cultural and historical resources, three unique impacts should be considered when working with offshore wind technologies: underwater noise, turbine strike, and visual impacts.
Underwater Noise: Turbine blades operating at normal speeds can generate noise and vibrations underwater, which may disrupt breeding sites, increase habitat fragmentation, and cause behavioral or physiological disturbance.
Turbine Strike: This term refers to the collision or barotrauma (physical damage to body tissue from changes in air pressure) that birds may experience from offshore wind turbines.
Visual Impacts: Offshore wind turbines may be hundreds of feet tall and can decrease the value of natural viewsheds. Aviation lighting placed on top of turbines may also impact the natural lightscape of the area.
Other Impacts: Impacts from construction and development activities, such as the burial of underwater transmission lines in the sea floor, may affect natural habitat, such as reefs, and impact ocean wildlife.
For more information on potential environmental, cultural, and historic impacts of offshore wind energy technologies, please reference the Outer Continental Shelf Alternative Energy Programmatic Environmental Impact Statement of 2007 or visit the links below.