Tidal energy farm proposed for Vineyard Sound
With little fanfare, an off-Island development company has filed plans to build an underwater tidal energy farm in Vineyard Sound. Representatives of Massachusetts Tidal Energy Company (MATidal), based in Washington, D.C., say their installation could potentially supply power to thousands of New England homes.
MATidal submitted a preliminary permit application on April 12 to the Federal Energy Regulatory Commission (FERC). If approved, the proposal calls for the installation of one or more clusters of underwater turbines, referred to in the application as "tidal in-stream energy conversion devices." The device is much like an aboveground wind turbine, but submerged to harvest power from the flow of the tide.
Each tidal device is expected to produce up to two megawatts of electricity, depending on the power of the current, enough to power 750 homes. The company is looking to install up to 150 units.
A diagram of the experimental tidal turbine in the Bristol Channel near England shows how the submerged mechanism operates. The single propeller device can be raised above water for maintenance, and is capable of generating 300 kilowatts of electricity. Web images from www.bbc.co.uk
Daniel Power, president of Oceana Energy Company, the parent of MATidal, said the project is in the initial planning phase. "This is all a new field," he said. "The way the world is right now, we're going to have to find some way to collect natural energy and convert it to something that people can use."
The application explains that each tidal device would have a rotating propeller between 20 and 50 feet in diameter, a generator, and an anchoring system. Mr. Power said the company is required to put a description of the device in the application. "We are still in the process of evaluating and validating technologies that are out there to collect the energy," he said.
Although it is believed that large amounts of energy could be harvested from Vineyard Sound, Mr. Power said the initial testing phase would determine if the area is suitable for a tidal farm. "We think that there's energy out there to be collected in the waters," he said. "If there's not any energy out there, we're wasting our time. But we'll find out."
The company is evaluating an underwater area between Naushon Island and the shallow regions of Lucas Shoal and Middle Ground, for the tidal farm. The project would connect to an existing underwater cable that runs between Nobska Point in Falmouth and a point on the north shore just west of the opening to Lake Tashmoo. The water depth ranges from 40 to 75 feet in the proposed areas.
MATidal applied for a standard three-year permit in which time the company would conduct environmental testing and build a pilot tidal device.
The tidal generators can be raised to the surface for maintenance.
Mr. Power said the company is studying tidal energy projects both in the development stage and currently in use. He cited a trial now in progress in Lynmouth, Devon on the south side of the Bristol Channel in England, where one experimental turbine was installed three years ago. The single 11-meter-long propeller can be raised above water for maintenance, and it is capable of producing 300 kilowatts of electricity.
Another experimental tidal power station near Hammerfest, Norway, has been operational since November 2003.
"We're trying to assess the strengths and the weaknesses and see how these technologies might be uniquely well suited for the tidal basin there," Mr. Power said. "We are also looking at technologies that are not yet in use."
Researchers say tidal farms are often more reliable than wind because of the general consistency of the tide; the amount of energy harvested doesn't change with the weather or seasons.
If FERC grants the permit, the preliminary study phase would create a three-dimensional image of the ocean floor to collect and analyze data concerning water flow and current speeds. Later studies may include the use of a sled-mounted video camera, remotely operated vehicles, and submerged sonar devices.
In the application, MATidal said they do not believe the project will negatively impact aquatic organisms, or wildlife, because of the slow rotation of the propeller blades. Other experimental turbines turn approximately 20 revolutions per minute.
"We will do it in a way that is, environmentally, about as benign as you can get," Mr. Power said. "And it will cause very minimal impact upon the eyes and the ears of the local populace."
There is a growing demand for energy, especially in the Northeast, the area that would use the tidal farm, according to MATidal's application. The company estimates there will be a 52-percent demand increase for energy in the next 20 years, representing a $17 billion per year market rise. MATidal estimates that renewable sources of energy may be expected to increase nine percent by the year 2020.
Cape Wind, the controversial offshore wind farm proposed for Nantucket Sound, would consist of nearly 130 wind turbines, each producing up to 3.6 megawatts of power on an average day. If installed, and when operating at peak production, the wind farm could supply power to nearly 75 percent of all homes on the Cape and Islands, according to proponents.
After encountering determined opposition among citizens and local politicians, the Cape Wind project is at a standstill.
No part of the tidal farm would be visible above the surface of Vineyard Sound, MATidal states in the application. "The devices generate power from natural marine tidal currents, and therefore are not dependent on fuel," MATidal said in the application. "Removing the fuel component...decreases environmental impacts and production costs tremendously. This form of energy production is essentially emission-free with no adverse impacts on air quality and minimal foreseeable adverse environmental impacts overall."
One of the best sources of energy is the moon's tidal effect, Mr. Power said, adding that water has 840 times the density of air, thus a relatively slow current could produce a large amount of energy. "I don't want to get into a contest with wind," he said, describing his proposal as just a different way of exploring green energy.
The company estimates that planning and studies supporting the project will cost between $1 and $4 million over the duration of the permit period. MATidal and its investors will cover the costs.
Joseph A. Cannon of the Washington-based law firm Pillsbury Winthrop Shaw Pittman, and Charles B. Cooper of TRC, an environmental permitting and planning company in Lowell, are listed as authorized agents for the project.
Jeff Brandt, an environmental consultant for TRC, said once FERC approves the preliminary permit, his company will begin feasibility assessments.
MATidal applied for a license under Part I of the Federal Power Act, which oversees federal regulations on waterpower development.
FERC will ultimately approve or disapprove the application, but other agencies can review the proposal and impose stipulations, Mr. Power said. Typically, FERC takes 60 days to review an application and grant a permit. The project is listed as number 12670 on the FERC web site.