Plan For World’s Biggest Tidal Project Dealt Blow

A plan to build a massive tidal barrage on the Severn Estuary – big enough to meet 5 percent of the United Kingdom’s electricity needs in one fell swoop – looks like it could be headed toward the same dismal fate as earlier proposals after a very skeptical parliamentary committee report.

Hafren Power is seeking government support to build a turbine-festooned barrage 11 miles long between Brean, England, and Lavernock Point, Wales, to take advantage of the Severn Estuary’s legendary tidal flows. The company says the project would produce 16.5 terawatt-hours of electricity per year – equivalent to the amount of energy that would be churned out by 1,500 3.6-megawatt offshore wind turbines – and it would do so for at least 120 years (a lot longer than anyone expects wind turbines to last).

image via Hafren Power

image via Hafren Power

The company is looking for government approval to carry out the £25 billion ($40 billion) scheme, as well as price support on the electricity produced. This kind of support in the U.K. often comes through “contracts for difference” that are granted to provide stable and predictable incentives for companies to invest in low-carbon generation.

Despite the company’s forecast that barrage power would be more economical than offshore wind, fear that such support would be substantial and “risk eating up an excessively large proportion of the funds available” to back other clean energy technologies was a key aspect of the Energy and Climate Change Committee’s harsh critique of the Hafren Power plan. The committee said it also remained unconvinced on the environmental front.

“It became clear during the course of this inquiry that more detailed, robust evidence about Hafren Power’s proposal and claims is needed,” committee chairman Tim Yeo said in a statement. “Our inquiry has brought more information into the public domain and furthered the debate, but we cannot recommend the Hafren Power scheme as currently presented to us.”

The Severn Estuary drains Great Britain’s longest river, the Severn, widening into the Bristol Channel as it divides Wales and England. Its attraction as a source of power is obvious: Massive amounts of water flow in and out of the estuary continually. A National Oceanic and Atmospheric Administration list of the 50 locations in the world with the largest tidal ranges includes several spots along the estuary.

Proposals to take advantage of this fact have come and gone, most recently in 2010, when the British government conducted a lengthy review and then announced it did not “see a strategic case for public investment in a tidal energy scheme in the Severn estuary at this time, but wishe(d) to keep the option open for future consideration.”

While the committee report is a blow to the latest Severn barrage plan, it doesn’t de facto kill it. The Cameron government responded that it still has an open mind and Hafren Power said it will fight on. The Welsh environmental group Friends of the Earth Cymru, meanwhile, said the report was spot-on, adding that it wanted to see smaller tidal projects pursued, pointing specifically at the unfolding Swansea Lagoon project.

Sports columnist, newspaper desk guy, website managing editor, wine-industry PR specialist, freelance writer—Pete Danko’s career in media has covered a lot of terrain. The constant along the way has been a fierce dedication to knowing the story and getting it right. Danko's work has appeared in Wired, The New York Times, San Francisco Chronicle and elsewhere.