Photo credit courtesy of NREL

The first underwater turbine to make use of tidal energy went live last week in Maine, supported by a $10 million investment by the Department of Energy.

The Ocean Renewable Power Company Maine’s Cobscook Bay Tidal Energy Pilot Project received the Energy Department money to build, install, and operate the hydrokinetic energy conversion devices situated at the easternmost tip of the state.

The turbine, with a rated capacity of 180 kW, is expected to generate enough power for 25 to 30 homes.

The electricity produced by the tidal generation will be sold by Ocean Renewable Power Company to Maine’s utilities under a 20-year power purchase agreement, according to The initial price of 21.5 cents per kilowatt hour is almost double the current average price of 11.21 cents per kilowatt hour for electricity in Maine.

Heritage’s Nick Loris, a critic of government subsidies for energy sources, said Washington should stop propping up industries that happen to have good connections in Washington. “Taxpayer-funded programs do not create jobs; they shift them from one sector of the economy to another,” Loris recently wrote. “The opportunity cost of government spending is the lost labor and capital extracted from other sectors of the economy to artificially support the politically preferred ones. If underwater turbines are a good investment, companies shouldn’t need subsidies to build them.”

The power company plans to construct a network of as many as 20 of the seafloor-mounted underwater turbines to eventually produce electricity for approximately 1,200 homes:

The first tidal generator is expected to begin delivering electricity to the regional power grid in September, starting small, with just enough to power 25 homes. It is the product of several years and millions of dollars in investment by Ocean Renewable Power’s backers and the Department of Energy.

The Cobscook Bay Tidal Energy Project cost about $21 million, including research and development, design and fabrication of three turbine units, installation, and environmental monitoring. The systems capture the energy of the moving water, rotating a turbine that powers a generator.

According to Energy Department estimates released in the project’s impact statement, 53 new jobs are expected to be created over the course of the eight-year pilot period. In announcing the project’s culmination this summer, Energy Secretary Steven Chu put the figure slightly higher, at around 100 jobs “supported” by the project.

Generating energy from tidal forces is more predictable and reliable than other forms of renewable energy, especially wind turbines.

Paul Jacobson of the Electric Power Research Institute told that predictability is crucial. “That’s highly valuable to the folks who have to manage the generation and transmission system,” he said. “To know how much power they can expect to get from a system over time is valuable.”

The Electric Power Research Institute is a recipient of approximately $1.5 million in Energy Department funding for a variety of ocean energy assessments, including ocean wave energy resource recoverability, fish injury and mortality, and available hydrokinetic energy from U.S. rivers.

The Energy Department believes the project represents the first step in promoting the development of tidal energy in the United States. Based on its own estimates from early 2012, the Energy Department projects that as much as 15 percent of the nation’s electricity could come from waves and tidal currents and up to one-third of the nation’s electricity demand could be generated along the coast, though it did not provide a specific plan on expanding the energy portfolio in the announcement.

The Energy Department has funded more than $87 million in marine and hydrokinetic projects since fiscal 2008, with more than 45 percent going to three states—Maine, Oregon, and Washington. Private industry received more than $49.4 million of the total, or 60 percent.

The Maine project’s $10 million award was the largest of the Energy Department’s Water Power Program projects.