Engineers say floating offshore is closer than it may seem

Source: Saqib Rahim, E&E reporter • Posted: Thursday, October 27, 2016

WARWICK, R.I. — Elon Musk wants to land on Mars, and scientists want to solve cold fusion. Then there are the engineers who think they can build windmills that float on the high seas.

Judging by what some of those engineers have to say, they think they’ll be first.

In fact, they consider themselves to be at the technological edge of the wind industry, as onshore wind has matured in the United States and offshore wind is emerging in the Northeast.

These turbines, it’s hoped, can sit far off the coast, reaping fierce winds. And while they’re currently more expensive than their cousins that attach to the ocean floor, their partisans think they can cut costs rapidly.

“This advent of new floating turbines does open up some possibilities,” David Hochschild, a member of the California Energy Commission, said at a conference here yesterday. “Thirty miles offshore, your projects are not visible. The avian impact issue goes way down. And I really think that if we can get the cost down, the future is very bright.”

It might be a far-out approach, but it has gotten the attention of the federal government.

Last month, the Department of Energy said “floating technologies have the potential to achieve costs that are equal to or even lower than fixed-bottom technologies by 2030.”

Floating turbines could achieve something current technology cannot: going further out, where the wind is stronger.

In the Northeast, fixed-bottom technology can work because the continental shelf is relatively shallow. But it won’t reach the deeper parts of the ocean floor. Almost 60 percent of the estimated technical wind potential is at depths beyond 60 meters, according to DOE.

But engineers are still playing with design. Not only does the machine have to withstand strong winds, but it needs to keep its balance in waves that can approach 100 feet. And it can’t be too expensive. One project, in Maine, uses cement as ballast. It hired local bridge builders to manufacture it.

Only five commercial-scale prototypes existed as of last year. But some in the industry believe they can scale up more quickly than people expect.

Part of that is because Europe is seeing dramatic cost cuts in conventional offshore-wind technology, and they’re spilling over.

Trine Ulla, head of wind asset management at Statoil ASA, said the company is commissioning a floating wind pilot next year. The Hywind Scotland project will feature five turbines in waters more than 100 meters deep.

It’s cheaper than the company’s last pilot from 2009, she said, and she expects more cost cuts to come.

“This is a market with unlimited potential if we want to make it work,” she said at the American Wind Energy Association’s Offshore WINDPOWER Conference.