Suman has cool links, including one to an MIT study about the grid reliability and infrastructure, but I don't have time to read it yet.
However I disagree with Suman and Jane about the crazy idea to have wind turbines off of Nantucket Sound. The Save our Sound website makes excellent points on its FAQ:
130 enormous turbines. These experimental turbines the largest in the world and are not yet in production use.
Covering 24 square miles, the plant will consist of 130, 417' wind turbines and a 100'x100x150' service platform with a helicopter pad and crew quarters. Each turbine blade will be 164 feet long with a total diameter of 328� (a rotating football field). Each 417� turbine will have a base diameter of 16 feet and an above-water profile taller than the Statue of Liberty (305�), the Pilgrim Monument (252�) or the canal bridges (275').
Each turbine will have about 150 gallons of hydraulic oil (19,500 gallons total), and the substation will have at least 30,000 gallons of dielectric oil and diesel fuel.
How far from shore?
The plant will be less than 5 miles from land at its closest point and present miles of variably rotating turbines to the shores of Cape Cod, Martha's Vineyard and Nantucket. As the National Air Traffic Controllers Association noted, the power plant will be within the flight paths of thousands of small planes. Commercial ferry lines have also said it will pose serious navigation hazards. The southern edge of the turbine field will be next to the main shipping channel to Nantucket.
How visible? The power plant will be visible well over 20 miles.
How much power?
Turbines run at just 25-40% efficiency. Maximum predicted output of the power plant is 420 megawatts, but this assumes a constant wind speed of 30 mph, with average output predicted at 170 megawatts (a generous 40% efficiency), assuming a constant wind speed of 19 mph. Maximum rotor speed is 15 mph with a tip speed of around 175 mph. Estimated total power generation of this 24 square-mile facility is .86% of the regional grid�s annual power needs at 2001 rates, although consumption grows at 2-3 percent yearly.
Where will this additional power go?
ISO New England is the regional power authority. Their most recent supply projections show Southeastern Massachusetts will have 3350.3 MWs of capacity in 2006, with a projected summer peak of 2180.0 MWs - yielding a 54 percent reserve margin - a surplus. Cape Cod is a power exporter.
Cape Wind's web site states that "Only when Cape Wind is supplying more electricity than the Cape and Islands can use will some of the electricity go off Cape." The truth is, because Cape Cod does not have a power shortage, generated power will be sold to the regional grid and will not directly benefit the Cape.
How much will we save?
Cape Wind claims $800 million in savings over 20 years, but since only 40% of power in NE is residentially used, this amounts to just 12-24 cent monthly reduction for the average residence.
What's in it for the developers?
Cape Wind will receive a federal tax subsidy, the Production Tax Credit (PTC), which equalizes wind power costs with other forms of power generation. The 2001 subsidy was 1.7 cents per kilowatt hour; this rate translates into an annual credit to Cape Winds of about $25 million of our tax dollars per year. A state subsidy adds another $40 million. And this project is not economically viable without the PTC, which is due to expire at the end of 2003. Clearly, the 'green' in this project will be flowing into the pockets of the wealthy developers, not to the people who live on Cape Cod, Martha's Vineyard and Nantucket.
Won't it reduce our dependence on foreign oil?
Oil used for electric power generation in the U.S. fell from 20 % in 1973 to 2% in 2001. The majority of our oil use, 70-80%, is for transportation, not electricity generation. The U.S. imports about half of its oil, with Canada, Saudi Arabia, Mexico and Venezuela the top sources of oil imports. European countries depend far more heavily on the Persian Gulf and North Africa for oil imports than the U.S. (Source: U.S. Dept. of Energy)
As of August 2002, ISO New England, the regional power authority, had before it proposed projects of 15,000 MWs of non-oil generation - this wind project has considerable non-oil competition. And given the unreliable nature of wind, quick-startup backup power from oil-fired peaking units may have to be used, so the wind farm might actually add to the need for oil.
What are the impacts of Cape Wind on fish and fishing?
Not a single local or national recreational or commercial fishing or shipping group supports this project. Those who use these waters, not power company developers, know the real effects this plant will have on the safety of navigation and fishing. The Sound is one of the richest fishing grounds on the east coast and a hugely popular recreation area. 130 turbines over 24 square miles will present significant obstacles to fishing, navigation and wildlife in all types of weather.
Many local fishermen make up to 60% of their income on Horseshoe Shoals. This project would block off a productive fishing ground to a group of people struggling to make a living. That's why the local and national fishing groups, including the 3000-member Massachusetts Fishermen's Partnership, strongly oppose this project. Other opposed organizations include:
� Mass. Division of Marine Fisheries
� Massachusetts Commercial Fishermen's Association (3,000 members)
� Cape Cod Commercial Hook Fishermen's Association
� Massachusetts Marine Trades Association
� Hy-Line Cruises | statement
� Steamship Authority | statement
� Cape Cod Marine Trades Association
� Mass. Boating and Yacht Clubs Association
� Massachusetts Fishermen's Partnership
� Massachusetts Lobstermen's Association
� Edgartown Charter Fishing Association
� Edgartown Shellfish Organization
� Recreational Fishing Alliance (75, 000 members)
This project basically adds no power independence, generates a tiny fraction of the regional need, has an enormous ecological footprint with potential for disaster in case of failure, poses a threat to shipping and aviation, is opposed by the regional fishing and tourist industry, and appropriates for private use a large public sporting and recreational resource. It also will require federal subsidies and will cost energy to run since wind is a variable source.
For more info on why wind will never be more than a niche energy source, see Steven den Beste's reference article (and followup).