Plans to build the first US undersea transmission system for offshore wind farms advanced on Monday when the federal government said there was no competition for the proposed project, which can now be subject to an environmental review without being delayed by an auction.

The US Department of the Interior issued a finding of no competitive interest on the plan by Atlantic Grid Holdings to build the $5 billion Atlantic Wind Connection, a 300-mile transmission line off five mid-Atlantic states to take as much as 7,000 megawatts of wind-turbine capacity from yet-to-be-built offshore wind farms.

The high-voltage direct-current line would feed power into the regional grid operated by PJM Interconnection at six onshore points, fewer than if wind farms established individual transmission lines, cutting their construction costs by 18%, according to Bob Mitchell, chief executive of AWC.

“This milestone allows the AWC to proceed to intelligently plan for the backbone transmission system that is necessary for an entirely new robust offshore wind industry to develop in America,” Mitchell said in a statement.

In comments to Breaking Energy, Mitchell said he will now be talking with the states, whose support is crucial to PJM’s backing for the AWC project. New Jersey, Delaware and Maryland will be the focus of AWC’s lobbying efforts in coming months, he said.

He will argue that the project will ease the congestion that cost PJM ratepayers $1 billion last year. “AWC will do an awful lot to reduce energy costs,” Mitchell said.

Unlike Europe, the U.S. has no operational offshore wind farms but developers are seeking to build them at various points between Massachusetts and Virginia. Proposals include the long-delayed Cape Wind project off Massachusetts, and the Fishermen’s Energy farm off New Jersey. Another plan to build a wind farm off Delaware was put on hold late last year when its developer, NRG Bluewater Wind, said it was unable to find investors.

AWC may become the world’s first multi-terminal undersea transmission line, contrasting with existing point-to-point lines that currently exist beneath European waters, Mitchell said.

The AWC project would be built in several phases designed to link Offshore Wind Energy Areas identified by the DOI. It is designed to improve system reliability and reduce congestion costs in the mid-Atlantic states. The so-called backbone is planned for 12 to 15 miles off the coasts of New York, New Jersey, Delaware, Maryland and Virginia, and construction would span about 10 years.

Critics say the project would fail to deliver what its backers claim.

While the system is designed to transmit up to 7,000 MW, in reality it would carry only some 2,100 MW about 60% of the time, and its power would be in continuous flux, putting additional strain on PJM’s marginal reserves, argued Jon Boone, a former University of Maryland professor who opposes wind power through his website,

“In short, the project would behave much like a defective machine–a lemon–generating no firm capacity and controllable only through curtailment,” Boone wrote in an email. “From a grid-stability point of view, the only thing worse than wind output is more wind output.”

Still, the DOI’s finding was welcomed by AWC investors including Google.

“Transmission is one of the key constraints to the wider adoption of clean energy, so this project was a natural fit with our corporate goal of investing in attractive renewable energy projects that can have dramatic impact,” said Rick Needham, Google’s Director of Green Business Operations.

Atlantic Grid Holdings now has 60 days to submit its general activities plan, after which DOI will begin its technical and environmental review. The following Environmental Impact Statement is expected to take about two years.