The waters around Scotland are also host to tidal turbine testing by several organizations, including Lunar Energy, Ltd., in East Yorkshire, England, which in March 2007 announced a deal with Germany-based power utility E.On UK, to develop a tidal stream power project of up to eight megawatts off Scotland's west coast.
Meanwhile, Florida researchers may soon be testing both wave- and tide-powered energy technologies that could take advantage of the Gulf Stream, which flows north-northeastward about 15 miles (25 kilometers) off Florida's southern and eastern shores at more than eight billion gallons (30 billion liters) per second. Researchers at Florida Atlantic University's Center of Excellence in Ocean Energy Technology in Dania Beach, Fla., are using a $5-million state research grant awarded in late 2006 to develop air-conditioning technologies that tap into the powerful Gulf Stream and large water temperature differences off Florida's shores. The researchers envision thousands of underwater turbines producing as much energy as 10 nuclear power plants and supplying one third of the state's electricity. The university is working with academic, government and industry partners on the project, including the University of Central Florida in Orlando, the U.S. departments of Navy and Energy, Lockheed Martin, Oceaneering International, Inc., in Hanover, Md., and Verdant Power, which has provided them with a 10-foot (three-meter) diameter rotor system that they used during 2002 East River tests.
Verdant first began testing its three-blade, horizontal-axis turbines from the surface of the East River in 2002. There have been some hitches: Some of the turbines' fiberglass blades broke under the tidal force. (The fiberglass blades will be replaced by the end of April with ones made of a magnesium alloy.)
Still, the site has produced nearly 50,000 kilowatt-hours of energy from December 2006 to May 2007. Verdant's East River testing spot has the potential to support as many as 300 turbines and nearly 10 megawatts of installed capacity. Verdant has been working for the past several years to tweak its tidal turbines so that by the end of 2010 they can deliver up to 1.5 megawatts to the city's electrical grid (800 households use about one megawatt).
The East River is not Verdant's only site. The company is also testing its technology in Canada's St. Lawrence River near Cornwall, Ontario, with the hope of creating a turbine infrastructure capable of producing an output of 15 megawatts. The company is also looking at sites in China and India.
It is unclear just how much it will cost to tap into energy from large bodies of water, since there is no tidal or wave power industry. Verdant's Taylor says his company is at least two years away from being able to quote costs to potential customers. That said, a rough cost estimate for Verdant's marine renewable energy technology is up to $3,600 per kilowatt hour—a higher price tag than wind power, fossil fuels or hydroelectric dams today, he says. However, he also points out that Verdant will be able to lower its costs over time through the mass production of its technology and the reduction of inefficiencies in the licensing and implementation processes.
The next step for Verdant in the U.S. is to apply for a Federal Energy Regulatory Commission (FERC) license that would allow the company to continue its pilot project attempting to prove tidal turbines can be a reliable source of energy for the city's grid. It took four years to secure the necessary permits from the New York State Department of Environmental Conservation and the U.S. Army Corps of Engineers.
That bureaucratic delay speaks to the difficulty of navigating the regulatory processes required to get such turbines into the water. Verdant's Taylor says his company has spent about $9 million getting its East River project to its current state, with one third of that cost going toward studies gauging how the turbines might affect vessel navigation, aquatic life and fish migration. Although the New York State Energy Research and Development Authority (NYSERDA) chipped in $3 million toward the East River project, Taylor says the time and money spent to secure changing, and sometimes redundant, regulatory approval wastes precious time that could be used testing new technologies. "That's got to change," he adds. "The world is burning up, and we're fiddling."