The trials and triumphs of offshore wind
An offshore wind farm under construction off Britain's coast.
When it comes to renewable energy, there’s a new kid on the block and he’s making lots of new friends quickly. We’re talking of course, about offshore wind. While once resisted as too expensive and too unsightly, the technology finally has found its sea legs and is really making a splash.
Europe is where most of the activity has been. It started with Vindeby, the world’s first offshore wind farm, off the Danish coast. Vindeby, commissioned in 1991, has 11 turbines, with a combined capacity of 4.95 MW.
That’s significantly less than the output of just one of 32 8 MW turbines that Danish-based Dong Energy is installing at the Burbo Bank Extension (PDF) wind farm off the English west coast near Liverpool. Dong, which also operates Vindeby, has 3,000 MW of offshore wind online, and plans to grow that to 6,500 MW by 2020. Their 21 existing facilities are off the coasts of Denmark, the Netherlands and the U.K. Dong, which both builds and operates these wind farms, is one of a growing number of players in this market.
Better known perhaps, are the turbine manufacturers. Vestas, the Danish turbine maker, has formed a joint venture with Mitsubishi Heavy Industries of Japan, to compete with Siemens, the longstanding frontrunner. General Electric is getting into the game as well, along with a number of Chinese manufacturers.
Why offshore?
Here are some reasons why offshore wind makes sense. First, it overcomes most of the not-in-my-back-yard (NIMBY) concerns about visual pollution and noise, although there has been resistance from certain upscale seaside communities, notably the Cape Wind project in Nantucket Sound, and Donald Trump’s lawsuit attempting to block a wind farm off the coast of Scotland, near a golf course he owns. (Although Trump lost, Cape Wind is apparently 'dead in the water.')
Winds at sea blow more consistently and with less obstruction than winds traveling across the land.
Second, wind speeds increase the higher you get off the ground. For that reason, larger turbines, with blades that reach hundreds of feet into the air, capture more energy than smaller turbines. This factor also combines with the previous one, as the larger the turbines, the more objectionable they tend to be. This is not an issue when they are far out at sea. (Of course, they generally aren’t that far out because it’s easier to plant them in shallow waters, not to mention the length of undersea cable required.) Also, a substantial portion of most countries' population lives near the sea.
Finally, winds at sea blow more consistently and with less obstruction than winds traveling across the land. That’s why hurricanes lose strength when they make landfall.
Still, until recently, costs were too high, and there was plenty of low-hanging fruit with less costly land-based turbines.
But as builders have come up the learning curve on how to anchor the turbines to the seabed more cost-effectively, and manufacturers have come out with new turbines that are both larger and more efficient, that equation is changing. Just since 2014, the cost of offshore wind has dropped from $166 per megawatt-hour to $82.
According to a recent piece in the Guardian, electricity from offshore wind will be less expensive than that produced by a new wave of nuclear plants currently being built. According to Hugh McNeal, a career civil servant who last year joined RenewableUK from the former Department of Energy and Climate Change, 'I don’t think there’s any doubt about the political commitment of any party, apart from perhaps UKIP, to offshore wind. I think it’s got an incredibly healthy future.'
So, what about the U.S., then?
At present, there is only one wind farm, the Block Island Wind Farm, off the coast of Rhode Island, that just came online last year.
The future beyond that is clearly an unknown given President Trump’s infatuation with fossil fuels.
However, a group of 20 governors from both red and blue states recently sent a letter to the president asking him to support wind and solar. On the question of offshore wind, the letter stated:
The Department of Energy’s 2015 Wind Vision Report predicted that our country’s offshore wind resources could support the installation of 22 GW of new wind by 2030 and 86 GW by 2050. If we capitalized on that potential, a new American offshore wind industry could create thousands of jobs in research and development, engineering, manufacturing, marine construction and other sectors.
Given its location, offshore wind presents greater development challenges than onshore wind, resulting in longer construction times and higher initial costs. In addition, most of the nation’s best offshore wind resources are found in federal waters — requiring federal permits and other logistic efforts that can add years to the construction timeline.
Because of these offshore development challenges, different tax incentives, infrastructure investments, and research are needed for offshore wind projects to be successful. Understanding this, the governors recently informed Congressional leadership that the nation’s offshore wind industry cannot grow without specific federal policy foundations that will encourage offshore wind development in shallow and deep water. The governors have urged Congress to approve comprehensive offshore development legislation as soon as possible.
According to the National Renewable Energy Laboratory (NREL), the gross wind resource along the two coasts of the U.S. amounts to 4,223 GW. That’s an amount roughly four times the entire generating capacity of the current U.S. electric grid.
So, the stage has been set for a massive increase in renewable power, courtesy of offshore wind technology. Governments around the world already are jumping in to take advantage of this opportunity. Hopefully, the U.S. won’t be left too far behind.
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