Commission supports tidal energy project, data collection tower 

Nantucket’s Planning & Economic Development Commission voted unanimously last week to support Edgartown’s proposed tidal generation project between Muskeget and Martha’s Vineyard.

At its Jan. 3 meeting, the NP&EDC endorsed the permit issued to Edgartown by the Federal Energy Regulatory Commission (FERC) to install tidal generators in Muskeget Channel. Commissioners also supported the University of Massachusetts at Dartmouth’s request for a $5 million grant from the Renewable Energy Trust of the Massachusetts Technology Collaborative to establish a Federal Marine Renewable Energy Center for the East Coast.

Such a center could provide technical assistance to Edgartown for tidal generation projects and all other renewable energy projects proposed for the Outer Continental Shelf, said Planning Director Andrew Vorce.

Generically known as in-stream energy conversion devices, tidal generators are set in channels where tidal currents, ideally, turn the rotors of the generators at three to eight knots or 2.6 to 6.9 miles per hour. These underwater turbines are typically unidirectional, meaning that their rotors can change direction with the tides. They come in a variety of configurations, including short tubes, double-ended funnels, or open rotors anchored to the bottom. Generators in a specific location would be connected to a nearby power grid with submarine cables.

The NP&EDC also voted unanimously at the meeting to direct Blue Wave Strategies of Boston, Mass. to xapply to the Minerals Management Service for a lease of one square mile of ocean south of Tuckernuck Island for the installation of a data collection tower to be used to determine the viability of building an offshore wind farm.

Both actions are in line with the Planning Commission’s and Nantucket’s belief that alternative energy installations are good for the Cape and islands, but not for Nantucket Sound.

“We’re working together with them [Edgartown and UMass Dartmouth],” said Vorce. “The whole idea is this is a collaboration with the two islands on the waters between the two islands. They’re applying to FERC and UMass is applying for a grant.

“Out of that funding would be funding for Edgartown and, hopefully, Nantucket to investigate renewable energy alternatives in this area.”

The grant money referred to would go toward such explorations, but would not cover the costs of tidal generator and wind turbine installations.

A data collection tower for potential wind turbines south of Tuckernuck, said Vorce, could start collecting data on wind speed, gusts, direction, wave heights, barometric pressure and air temperature in about three years.

At its July 2007 meeting, the commission had endorsed a plan for Nantucket, Edgartown and the University of Massachusetts at Dartmouth to jointly file an application with the Federal Energy Regulatory Commission to build tidal generators between the two islands. But the Planning Commission is now focusing on wind turbine-generated power south of Tuckernuck, one of several alternative sites suggested for Cape Wind Associates’ 130-turbine installation that is now proposed for Horseshoe Shoal in Nantucket Sound.

Edgartown filed its preliminary permit application on July 30 with FERC and has since received its permit. Edgartown’s reasoning for doing such a project with UMass-Dartmouth is to secure renewable energy for Edgartown at the cheapest possible rate, rather than one set by one of two private companies – Natural Currents Energy Services and the Oceana Energy Company – already surveying island waters for possible tidal energy generation sites.

Natural Currents Energy Services, LLC, a Highland, N.Y.-based firm is proposing to generate three gigawatts of power by installing tidal energy generators in Nantucket Sound between Nantucket and Chappaquiddick on Martha’s Vineyard. That is about 4.2 times the amount of electricity – around 70 megawatts – flowing to Nantucket right now.

Calling it the Nantucket Tidal Energy Plant, Natural Currents Energy Services is in the preliminary permitting phase of the project that – under ideal review and permitting conditions – would have its tidal generators online by 2011.

The Oceana Energy Company of Washington, D.C. received a preliminary permit from the FERC last summer to test the waters of Vineyard Sound in an area bounded by the southwest end of Naushon Island and extending northeast on both sides of Lucas Shoal and Middle Ground, according to Oceana’s preliminary permit filing with FERC.

Oceana, which is going to be building its own underwater turbines, told the FERC it would install 50 to 100 units with propeller diameters of around 35 feet in water as deep as 75 feet.

Theoretically, Oceana would like to generate 25 to 100 megawatts, with each generator producing 500 kilowatts to two megawatts of electricity, enough
power for about 750 homes.

By Peter B. Brace
Independent Writer

The Nantucket Independent

9 January 2008