First grid-connected floating turbine is launched off Maine’s coast

Source: Katherine Ling, E&E reporter • Posted: Monday, June 3, 2013

Maine’s famous lobster boats have a new water companion: a grid-connected offshore floating wind turbine.

The Energy Department and University of Maine announced today the launch of the nation’s first grid-connected offshore floating wind turbine prototype off the shore of Castine, Maine. The 65-foot-high prototype is the world’s first concrete-composite floating wind turbine to be deployed. It is only one-eighth the size of a planned 6-megawatt, 423-foot rotor diameter design that will anchor a larger wind farm planned by the University of Maine-led DeepCwind Consortium.

The wind farm would generate 5 gigawatts of power by 2030, employing 170 floating turbines located 20 to 50 miles offshore, according to the consortium. That is equivalent to about five nuclear energy power plants.

The goal of the prototype, developed with $12 million in DOE funding over a five-year period, is to collect data to test and prove the ability of the “VolturnUS” prototype to help address technical barriers to bringing down the cost of offshore wind, according to DOE.

The DeepCwind Consortium’s goal is to reduce the cost of offshore wind to 10 cents per kilowatt-hour by 2020, in order to compete with other forms of electricity generation without subsidies, the consortium said in a statement.

Offshore wind energy is expected to cost about 24 cents per kilowatt-hour in 2016, far higher than energy from onshore wind farms or conventional fossil fuels, according to federal economists. The higher costs stem from the lack of an established supply chain in the United States for offshore wind and from the fact that some equipment and ships must be imported from Europe. Installing turbines in the ocean is also more costly, and there is currently no transmission to carry the power to market.

The University of Maine’s concrete-composite floating wind turbine aims to be more efficient and cheaper in part through a unique semi-submersible platform that uses a lower-cost concrete foundation in addition to a lighter-weight composite tower. Current offshore wind turbines, found mostly in Europe, are based on expensive foundations anchored to the ocean floor.

A recent Brattle Group study, commissioned by pro-renewable groups, found that with as little as $18 billion over the next two decades, the offshore wind industry could reach “grid parity” with fossil fuels, with “only a minor impact on electricity rates” (Greenwire, March 1).

Maine Republican Sen. Susan Collins and Delaware Democratic Sen. Tom Carper reintroduced a bill in March that would offer an investment tax credit to the first 3,000 MW of new offshore wind projects, which would likely cover at least the first several offshore wind farms. Companion legislation was introduced in the House by New Jersey Reps. Bill Pascrell (D) and Frank LoBiondo (R).

All four of Maine’s congressional representatives are scheduled to be at the VolturnUS prototype launch, with Collins slated to break a bottle of Madeira to mark the occasion, according to a DeepCwind Consortium agenda.

DOE last year awarded the University of Maine a separate $4 million grant for a larger offshore wind demonstration called Aqua Ventus I as part of funding for seven offshore wind design and engineering projects that could achieve commercial operation by 2017. DOE will choose up to three of these projects for additional funding in 2014, the agency said. DOE said in its original announcement of the funding that these projects could also be eligible for up to $47 million over four years, subject to congressional appropriations.