Governors' Wind Energy Coalition

The grants are intended to help the projects, off the coasts of New Jersey, Oregon and Virginia, begin delivering electricity by 2017.

“Offshore wind offers a large, untapped energy resource for the United States that can create thousands of manufacturing, construction and supply chain jobs across the country and drive billions of dollars in local economic investment,” Ernest J. Moniz, the energy secretary, said in a statement.

The announcement represents the next phase of an Energy Department push to invigorate the industry by promoting innovation to help bring the cost of offshore wind power into line with that of conventional electricity production.

It came on the same day that Siemens said it would move the headquarters of its power-generating operations to the United States, not only to capitalize on the booming oil and gas industries but also with an eye on the potential growth of the offshore wind industry.

Far more advanced in Europe, the harnessing of offshore wind has yet to take root in the United States. It has been stymied by engineering, permitting and financing challenges, as well as political and community opposition in some corners.

Near the end of 2012, the Energy Department announced that it would make $4 million grants to seven demonstration projects, which were working through their engineering, site evaluation and planning stages.

Of those, Fishermen’s Energy, a venture to bring five turbines of five megawatts each to the waters near Atlantic City; Principle Power, which seeks to install five six-megawatt turbines off the coast of Coos Bay, Ore.; and Dominion Virginia Power, which hopes to put two six-megawatt turbines off the shores of Virginia Beach, won the larger grants.

The department is also working with two other projects — one planned for Maine near Monhegan Island and the other for Lake Erie — to further develop their technologies.

Getting an Energy Department grant to develop a new technology can be helpful but is certainly no guarantee of success. The department tries to pick the applications most likely to succeed, but sometimes it picks wrong.

In November 2012, the department selected Babcock and Wilcox, a well-established nuclear technology company, to develop a small reactor that could be built in a factory and delivered by truck or barge. The department offered a dollar-for-dollar cost match that could have reached over $200 million. But this year the company backed off on the technology and began laying off workers.

The other recipient of money for small reactor work was NuScale Power, of Corvallis, Ore., which received $226 million in December 2013 and is moving forward with developing a small reactor.