The Block Island Wind Farm

The first turbine of the Block Island Wind Farm is installed. Photo: Deepwater Wind.

By George Harvey

Construction at the Block Island Wind Farm, off the coast of Rhode Island, is nearing completion. The developer, Deepwater Wind, has not yet given a date for completion, but the foundations are already in place and waiting for masts. The nacelles, turbines, and blades have arrived from Europe. Everything is set for final assembly and the project is expected to be completed during the summer, followed by testing and commissioning in the fall.

The Block Island Wind Farm is not impressively large, by world standards. It has five turbines with a combined capacity of 30 megawatts. It will cover the needs of about 18,000 residents, including those on the island and others on the mainland. In one sense, however, it is an undertaking of huge importance. It will be the first offshore wind farm in the United States.

The wind farm will be of even greater importance to the residents of Block Island itself. Historically, the cost of cables to the mainland were prohibitive, so the island has always depended on locally burned fossil fuels for electric power. That has meant use of diesel generators, whose noise and pollution were not the only thing to complain about. On top of everything else, electric power has cost up to 54¢ per kilowatt hour (kWh).

One major benefit of the wind farm is that since power is being sent both to the mainland and the island, Block Island is now tied to the grid. Since the cost of the submarine cable from the wind farm to the island will have to be paid down, the rate reduction will not be to a low level, but it will go down by 40%.

The costs of offshore wind power have been declining sharply of late. A consortium of businesses recently joined the government of Scotland to fund research aimed at getting it down to $130 per megawatt hour (MWh), or 13¢/kWh, wholesale. Surprisingly, the same week that was announced, the Danish utility DONG signed a contract at just over $80 per MWh. When transmission costs are added to that cost, the price was still less than $100/MWh.

There are more installations under way, though all are in pre-construction stages. Deepwater Wind has made progress getting permits for the 90-MW Deepwater One South Fork, thirty miles east of Montauk, New York. The Lake Erie Energy Development Corporation, or LEED-CO, says it will have completed Ohio’s first offshore wind farm, six turbines off the coast of Cleveland, by the end of 2018. With the decline in prices for wind power, we will doubtless see more coming.

Massachusetts is mandating up to 1600 MW in a law passed in early August. Denmark’s DONG Energy is already interested in developing an offshore wind farm of up to 1000 megawatts in the waters off the coast of Massachusetts.