December 16, 2010 | 12:00 PM | By

Cape Wind and Deepwater Wind side-by-side

FILED UNDER: Mitigation, Cape Wind, wind energy

flickr/Nick Treby

Offshore wind turbines in the U.K.

At my request, my colleague (and local Cape Wind expert) Sean Corcoran has put together a side-by-side comparison of two proposed offshore wind projects in our proverbial backyard: Cape Wind (slated to be first offshore wind farm in the U.S.) and the Deepwater Wind Energy Center (which would be the largest offshore wind farm in the U.S.). I’ve taken the liberty of turning it into a table:

Cape Wind (MA) Deepwater Wind Energy Center(RI)
Developer Energy Management Inc. Deepwater Wind, LLC
Location Nantucket Sound, about 5.2 miles away from the mainland. Rhode Island Sound, about 18 miles away from mainland
Footprint 24 square miles 270 square miles
Number of turbines 170-turbine proposal reduced by developer to 130-turbines 100-turbine proposal increased to a 200-turbine proposal
Power transmission Connects to the New England grid, coming ashore on Cape Cod Connects to both the New England and the New York grids, coming shore on Rhode Island and Long Island
Turbine height Rise about 440 feet above the water Rise about 525 feet above the water
Distance between turbines Parallel rows about .54 miles apart, with turbines in a row .34 nautical miles apart Approximately .8 mile
Energy production Rated to produce 468 megawatts. According to Cape Wind, average expected production will be almost 75% of Cape and Islands usage. Rated to produce 1,000 megawatts. According to the New York Times, one megawatt is enough to run a Super Walmart.
Price of energy 18.7 cents per kilowatt hour for the first year, increasing 3.5% each year over 15 year contract Estimated by developer to be in the “mid-teens” per kilowatt hour
Construction costs Cape Wind is not saying how much the project will cost, but government estimates fall around $2.5 billion Estimated at $4.5-$5 billion
Status Project and lease in Nantucket Sound approved by the Department of the Interior; Power purchase agreement approved by state Application for lease filed with the Department of the Interior
Begin construction 2011 2014
Turbines spinning 2012 2015

The only thing I would add to this extensive comparison is an emerging parallel in opposition to the projects coming from fishermen who fear that insurance companies will bar them from fishing within the leased areas – both major fishing grounds.

  • Jen

    Is there any possibility that Cape Wind will want to change to the higher towers since they generate more power?

  • Heather Goldstone

    I asked Sean Corcoran, and he said that would almost certainly trigger more permitting so seems unlikely at this late stage.

  • Silfox

    Cape Wind is a terrible idea.It will destroy Horseshoe Shoals as a prime sport fishing area, known throughout the East coast. Cape Cod is famous as a recreational destination. Why are the fishermen and the tourist industry not objecting to this? –Elliott Taylor

  • Robertscott_2

    why not one new england project to produce the maximum power for the cheapest price-too many hands out for thier piece of the pie. this should be a single regionwide project whose goal is to benefit all the residents of the region equaly.