PORTLAND, Maine — A Maine tidal energy company says its prototype underwater power system has passed all of its tests, paving the way for a commercial unit to be connected to the region’s grid by year’s end.
Ocean Renewable Power Co. says the unit that finished testing in December produced grid-compatible electricity and appeared to cause no harm to marine life. The company plans to install a larger unit off eastern Maine that will deliver power to the Bangor Hydro Electric Co. grid.
The 150-kilowatt unit will power up to 60 homes, and the company intends to install more of the units in coming years, increasing capacity of 3.2 megawatts by the end of 2014.
“We think that within our next five years, we’re going to be competitive with any renewable power options, and possibly compete with fossil fuel sources,” company President Chris Sauer said.
Another tidal power company, New York-based Verdant Power, hopes this year to put new underwater turbines in New York City’s East River, where they’ll connect to the grid.
In its report completed late last month, Ocean Renewable says its prototype produced electricity on a prolonged and consistent basis, and while unattended.
Furthermore, underwater video cameras and sensors indicate there was no harm to fish, which appeared to go out of their way to avoid the unit, the company said.
The Ocean Renewable unit self-starts when the current reaches 2 knots and produces increasing amounts of electricity as the tidal currents reach up to 6 knots. All told, the unit produces power for 20 to 21 hours a day as the tide comes and goes twice in each 24-hour cycle, the company said.
Like Verdant Power, Ocean Renewable needs approval from the Federal Energy Regulatory Commission to proceed with its plans. The company plans to file its final application for its commercial turbine off Eastport within four to six weeks, Sauer said.
Ocean Renewable holds permits for three sites in the area, one of the world’s best tidal sites, where twice a day the tide rises and falls 20 feet.
Ocean Renewable and Verdant are among the companies racing to harness tidal power. They’re considered to be the most advanced tidal power developers in the U.S. but are trying to catch up with those in Europe.
“It’s a whole new field with daily discoveries. That’s what makes it exciting,” said William “Trey” Taylor, president of Verdant Power.
Tidal power appeals for a number of ways. Water’s greater density, compared to wind, means fewer turbines are needed to create the same amount of power. And tides, unlike the wind, are predictable. But perhaps the greatest advantage is that the underwater gear is hidden from sight, unlike wind turbines, so there are no complaints about aesthetics.
Verdant’s design looks a lot like a wind turbine, only it’s underwater. Ocean Renewable uses rotating foils that lend the appearance of a manual reel mower.
Both companies are making rapid advancements compared to the early development of wind power. But they still face formidable challenges. One problem is that regulations don’t exist; another is that tidal power efforts haven’t drawn large amounts of investor money, observers say.
“Currently, the biggest obstacle to development of the tidal power industry is lack of funding for further development of the technology and for permitting and licensing of demonstration projects,” said Paul Jacobson, water power manager for the Electric Power Research Institute.
Nonetheless, tidal power companies see great potential. Ocean Renewable officials think there’s potential for up to 100 megawatts of tidal power in the Eastport-Lubec area. And Taylor say there’s a lot more potential in neighboring Canada, where he said the Bay of Fundy’s tremendous tides moving through each day carry the daily equivalent energy of four hurricanes.
Ocean Renewable and Fundy Tidal Inc. of Westport, Nova Scotia, have formed a partnership to develop a tidal energy project in the Bay of Fundy off southeastern Nova Scotia.
Next year, the companies plan to begin producing tidal-generated electricity at Petit Passage using Ocean Renewable’s underwater turbine system, the companies announced this month. The Petit Passage is about 50 miles from Ocean Renewable’s three sites off Eastport.