First Big U.S. Offshore Wind Farm Offers $1.4 Billion to Customers

Massachusetts electricity users will reap $1.4 billion in benefits over 20 years from the first commercial-scale offshore wind farm in the U.S.

Avangrid Inc. and Copenhagen Infrastructure Partners, joint developers of the 800-megawatt project south of Martha’s Vineyard, expect to provide power and renewable energy credits at a levelized price of 6.5 cents per kilowatt hour, in 2017 dollars, over the term of the contracts, according to a letter Aug. 1 from the State Department of Energy Resources.

That makes the Vineyard Wind project about 18 percent cheaper than other alternatives, according to the letter. It’s ...