Wind Power Sails
Ahead Off Cape Cod

Nantucket Morning

Cape Wind, the first U.S. offshore wind project appears poised for construction. In October 2010, after nine years of political wrangling, public opposition and countless government reviews, U.S. Interior Secretary Ken Salazar and Cape Wind President Jim Gordon signed the first lease for an offshore wind farm in federal waters. During his signature speech, Salazar predicted that high priority areas for wind development would be identified along in Atlantic states by the end of the year and that the government would take steps to shorten the permitting process.

Located off historic Nantucket, Cape Wind offers the ideal conditions that developers seek when looking to exploit wind power—proximity to power markets and the make-or-break variable, sustained wind speed. To be profitable, a wind farm must operate in an area with strong, dependable winds.

Wind Turbines

This wind farm off Nysted in southern Denmark supplies as much as 166 MW of electricity. European countries are planning to add much more offshore wind capacity in the coming decade.

As it turns out, the best winds are found offshore, away from topographical obstructions such as hills and forests. Data from the Department of Energy has identified the wind potential for most locations in the United States. Aside from activity along some narrow ridgelines, the strongest, most sustained winds in the eastern half of the country are found off the coast of New England and in the waters of the Great Lakes.

The situation is similar in Europe, where the North Sea winds are superior to those on shore. For nations such as Denmark, Germany, and the Netherlands, which depend on wind power to supply an increasingly large fraction of their electricity demand, the high winds in shallow waters offshore have become an attractive resource. Indeed, according to the European Wind Energy Association, a trade group based in Brussels, as of June 2010, there were 2396 megawatts of offshore wind turbine capacity around Europe with another 16 wind farms totally 3972 MW under construction.

The situation in the United States is quite different. At present, there are no offshore wind farms.

The Cape Wind project will be impressive once completed: 130 turbines spread across 24 square miles of water between Nantucket and mainland Cape Cod, with the highest turbine blade tip stretching 440 ft. above the water. The peak generating capacity will be 420 MW, or enough, its backers say, to power three-quarters of the average demand on Cape Cod, Nantucket, and Martha's Vineyard.

Considering the concerns in the Northeast about conventional electrical generation from coal-fired boilers and nuclear plants, it would be easy to believe that a large, emissions-free generating facility would be widely welcomed. But while the Cape Wind project lined up quite a bit of local support (including a number of local town councilmen and state assemblymen), the opposition was surprisingly fierce.

One group that came against the wind farm was commercial fishermen. Boating and fishing groups contended that the 130 towers would be a navigation hazard and offshore construction could imperil the fisheries. A much more high-profile opponent has been made up of wealthy homeowners along the shore, including the late Massachusetts Sen. Edward Kennedy and environmental activist Robert F. Kennedy, Jr. The visual impact of the turbines against the horizon, they feared, could hurt both tourism and property values.

Though the proponents of Cape Wind appear to have won the war, the battle is not entirely over. Even after the signing of the federal lease, The Alliance to Protect Nantucket Sound filed a lawsuit seeking to force the Massachusetts to release documents it claims would reveal behind-the-scenes wheeling and dealing between the wind farm developers and the governor’s office. It appears the battle won’t cease until the turbines start turning.

[Adapted from “Wind Out of Their Sails,” by Jeffrey Winters, Associate Editor, Mechanical Engineering, June 2006.]

As it turns out, the best winds are found offshore, away from topographical obstructions such as hills and forests.


March 2011

Jeffery Winters

by Jeffery Winters