Developers unveil plans for 24 underwater turbines off coast near Eastport

By Tom Walsh, BDN Staff
Posted Oct. 26, 2012, at 5:27 p.m.

BANGOR, Maine — Portland-based Ocean Renewable Power Company officials met Friday morning at the Maine Department of Environmental Protection’s regional office in Bangor with a small group of state and federal regulators to outline plans to place 24 underwater turbines in the Western Passage of the Bay of Fundy in 2014.

The project would be the next phase of Ocean Renewable’s ongoing Washington County pilot project involving the first generation of its TidGen turbine, which was submerged at a 60-acre Cobscook Bay test site near Eastport in mid-August. Deployment of the 80,000-pound turbine assembly followed millions of dollars of investment during eight years of design, fabrication and testing.

After being underwater for 12 weeks and transmitting electricity since mid-September from the pilot project unit to an on-shore Bangor Hydro substation, the turbine array was pulled from the water Thursday for an onshore quarterly inspection required under the terms of a $10 million Department of Energy federal grant. The unit is expected to remain in dry dock at the Eastport Boat School pier for the next two weeks. Two other similar turbines will be submerged some time next year.

Nathan Johnson, ORPC’s manager of environmental affairs, said Friday that an initial inspection showed “no surprises” and that the unit has been performing within design specifications. The rectangular turbine resembles an elongated paddle wheel that is 98 feet wide and almost 20 feet high. When submerged in a 6-knot tidal current, the turbine can generate as many as 150 kilowatts, enough electricity to supply 20 to 25 homes.

Herbert Scribner, ORPC’s director of environmental affairs, said Friday that the planned deployment of next-generation turbine technology in a 170-acre area of Western Passage of Paris Point represents “Chapter Two in Maine’s tidal energy effort.”

“The technology for Western Passage evolved from the work we are doing in Cobscook Bay,” Scribner said. “The plans are far more mature, because we know more and are learning more on a continuing basis because we are operating now.”

While the Cobscook Bay unit is submerged at a depth of less than 100 feet and is anchored to the sea floor, the technology being planned for deployment in Western Passage will operate in fast-flowing waters at depths ranging from 150 to 400 feet and will be tethered to the bottom. In some areas, turbine arrays will be stacked vertically.

Unlike Cobscook Bay, the Western Passage is a busy commercial shipping lane and an active fisherypopulated by a variety of whales, dolphins and seals.

“Western Passage is a very different place,” Scribner said. “This is a pilot project in which we are trying to identify the best way to design a hydrokinetic device for deeper, faster water and to get power to shore. When we’re ready, we’ll come back with a commercial application.”

Scribner said the lessons learned in the Cobscook Bay pilot project are being shared with other tidal-generation researchers, not only on the West Coast, but internationally as well.

“Our success has bred success,” said Glen Marquis, ORPC’s project development manager. “We’ve have had a lot of interest globally.”

ORPC plans to submit its draft pilot license application for its Western Passage project to the Federal Energy Regulatory Commission in June of next year, with a final application to be submitted by year’s end.

The company expects to continue to grow its Washington County generation capacity in the coming years to eventually meet the 5 megawatt maximum output authorized by the Maine Public Utilities Commission. ORPC is now negotiating 20-year power purchase agreements with Maine’s public utility companies.

http://bangordailynews.com/2012/10/26/news/down-east/developers-unveil-plans-for-24-underwater-turbines-off-coast-near-eastport/ printed on September 19, 2014