Costs

Offshore wind farms are more expensive to build and maintain than onshore wind farms due to the higher cost of larger turbine structures, offshore turbine foundations, and sea transmission cables. DOE estimates that constructing and installing an offshore wind farm costs at least $2,400 per kilowatt of capacity,  compared to $1,650 (in 2006  dollars)  for  an onshore wind farm. In July 2010, the Cape Wind developers and a local utility set a price of 18.7 cents per kilowatt- hour for residential consumers, somewhat higher than the average 2010 residential retail price of 16.6 cents per kilowatt-hour in New England. A 2010 report by the UK Energy  Research Centre  predicted that the  cost of offshore  wind power was likely to drop 25 percent by 2025.