Best Bet For U.K. Wave Power: Way Offshore

To get the most bang for their buck, U.K. wave energy developers need to look well offshore, according to a new study that aims to pinpoint the nation’s most economically attractive spots for development.

Carbon Trust said the most cost-effective wave resources can be found 100 kilometers or more from shore on the edge of the United Kingdom’s continental shelf. In particular, areas at the edge of the Rockall Trough to the west of Scotland and off Cornwall in southwest England, where the waters are a few hundred meters deep, could yield energy at half the cost of current, nearer-to-shore sites that are being considered.

carbon trust uk wave energy

image via Carbon Trust

What makes the sites more economical isn’t that building and setting up wave devices farther out at sea is less expensive; it’s that the sheer power of the waves in these areas offers vastly greater payoff.

The analysis by Carbon Trust – a “not-for-dividend” company that researches, analyzes, strategizes and invests in carbon-reducing technologies – sets up a fascinating new scenario for wave development in the U.K., where the technology is young and largely untested, but is farther along than anywhere else.

“It is technically possible to extract a significant proportion of this energy at the attractive sites by using farms of wave energy devices,” the report summarizes. “To do this many rows of long farms facing the Atlantic would be required. These might total around 1,000 km in length and average 180 km from shore. They need not necessarily be placed in a single continuous line. If all of these were built then around 95 TWh/y could be extracted from the offshore sites identified.”

carbon trust uk wave power study

With much greater production, the cost of energy decreases away from shore until waters become very deep. (image via Carbon Trust)

That figure, 95 terawatt-hours per year, gets scaled down to what Carbon Trust calls a realistic 32-42 TWh/year “taking into account practical and economic constraints,” such as making space for shipping lanes, and leaving gaps for fishing and to mitigate a “barrier” effect on sea mammals. But 42 TWh is still a hefty 11 percent of the U.K.’s current annual power generation under this scenario, which imagines wave farms totaling around 500 km in length.

“This new research identifies the major wave frontages for commercial development in the coming years,” Stephen Wyatt of the Carbon Trust, who wrote the report, said in a statement. “If we can continue to innovate to prove the technology at scale and to bring down costs then there is every reason to believe that wave power can be providing a significant contribution to our energy needs out to 2050.”

A 66-page PDF of the full report, “UK wave energy resource,” is available here.

Pete Danko is a writer and editor based in Portland, Oregon. His work has appeared in Breaking Energy, National Geographic's Energy Blog, The New York Times, San Francisco Chronicle and elsewhere.