Hard rocks and basking sharks kill off plans for £5.4bn offshore wind farm

Government plans to become a global wind powerhouse were dealt a further blow today, when a giant £5.4bn project off the west coast of Scotland was scrapped, because the sea bed was too hard, the waves were too strong – and because it would disturb thousands of basking sharks.

In the week after George Osborne sought to boost investment in offshore wind power in his Autumn statement by increasing its subsidy, Scottish Power became the second big-six energy provider to scrap a major project in less than a month.

Scottish Power pulled the plug on the Argyll Array Offshore Windfarm project, to the west of the Island of Tiree, which would have provided enough power for 1m homes, after five years in the planning. It blamed a much-harder than expected sea bed made of volcanic rock, which would have involved an additional and hugely costly drilling programme, and the discovery that the surrounding sea was much wilder than previously thought.

The company made its decision following a series of indepth environmental and technical studies, which threw up an additional new hurdle – it turns out that the basking sharks that had occasionally been spotted off the coast actually numbered in their thousands and would need to be built around.

Jonathan Cole, head of offshore wind at Scottish Power, said that the site had great potential in the longer term, but that the technology to exploit the blustery conditions could be ten to fifteen years away.

“We believe it is possible to develop the Argyll Array site, it has some of the best wind conditions of any offshore zone in the UK.”

“However, the rate of progress in development of foundation and installation technology has been slower than anticipated. The current outlook for offshore wind deployment in the UK suggests this will not significantly improve in the short term,” he added.

The windfarm would have provided enough power to supply up to 1m homes. It would involved the construction of up to 300 turbines, each one up to 662 feet tall.

The decision scrap the project came just three days after the government’s own energy and climate change advisor, the Committee on Climate Change, urged the coalition to clarify its position on renewable energy after making a series of moves many believe are deterring investors from backing renewable power projects. These include scrapping a target to green Britain’s electricity supply by 2030 and reviewing the country’s previously-agreed carbon emissions targets for the 2020s, in the spring.

Lord Debden, chairman of the CCC, said this week: "The Government should confirm the [2020s carbon targets] as a matter of urgency. This would remove the current uncertainty and poor investment climate. It would provide a boost to the wide range of investors who stand ready to invest in low-carbon technologies."

Scottish Power insisted yesterday that its decision to scrap the Argyll project had nothing to do with government policy and was purely “site specific” – an explanation experts said sounded plausible. The company said it was progressing with another, larger, offshore windfarm in East Anglia, where the seabed was much softer and the waves gentler.

Will Straw, associate director of the think tank IPPR, said: “Scottish Power’s explanation does sound reasonable. But it’s still another set back for an industry that has really been feeling the squeeze from a lack of clarity by government. And it’s bad timing – only last week George Osborne announced increased support for offshore wind.”

That increase, saw the guaranteed price that offshore windfarms will receive for the electricity they generate increase from £135 per megawatt hour, to £140, for 2018.

Last month, German-owned RWE npower said it was pulling out of the £4bn Atlantic Array project in the off the North Devon coast because it was so technically difficult that the economics did not stack up.

These cancelled projects are a blow for the Government, which is looking to bigger windfarms in deeper waters to help provide low-carbon power. It wants to generate 15pc of energy from renewable sources by 2020.