There are currently 14 U.S. offshore wind projects in advanced development, and the country has sufficient resources to support at least 54 GW of offshore wind capacity, according to new reports released by the U.S. Department of Energy (DOE).
The Offshore Wind Market and Economic Analysis report, produced by Navigant Consulting for the DOE, says there has been steady progress for the U.S. offshore wind energy industry over the past year. The report says 14 projects representing nearly 4.9 GW are in advanced stages of development. This means the projects have either been awarded a lease, conducted site studies or obtained a power purchase agreement.
The report notes that two of the U.S.' most advanced projects – Cape Wind and Deepwater's Block Island project – have moved into their initial stages of construction. In addition, the report says the U.S. government's commercial lease auctions for federal Wind Energy Areas have contributed to more projects moving into advanced stages of development.
The report also finds that globally, developers continue to build offshore wind projects farther from shore in increasingly deeper waters, while increased turbine sizes and hub heights enable higher efficiency and output from turbines. Worldwide, the report says the average capital cost for offshore wind projects completed in 2013 fell 3.7% per kilowatt-hour from 2012, with an additional decrease expected in 2014. Total project installation costs have fallen 6% since 2011, the report adds.
Meanwhile, the National Offshore Wind Energy Grid Interconnection Study has found that the U.S. has sufficient offshore wind energy resources to enable the installation of at least 54 GW of offshore wind capacity. The DOE-commissioned study was led by ABB, AWS Truepower, Duke Energy, the National Renewable Energy Laboratory and the University of Pittsburgh.
The report says at a regional or national level, offshore wind energy may provide significant value. The study estimates that the 54 GW of offshore wind could reduce the national annual electricity production costs by approximately $7.68 billion, which corresponds to approximately $41/MWh of offshore wind added to the grid. The report says these savings can help justify the high initial investment costs.
Furthermore, the report says the appropriate technologies exist for the interconnection of large amounts of wind energy to the U.S. grid. Multiple technologies for both high-voltage AC and high-voltage DC systems already exist that can be used to bring offshore wind electricity to the onshore grid. Some technologies may also help alleviate troublesome congestion in the onshore system, the report adds.