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Tllting at offshore wind

Offshore wind is moving ahead rapidly in the UK. There is 1.5GW in place, over 2GW in construction and 1.7GW with approval. And DECC now says that up to 18GW could be installed by around 2020.

So far most of the projects have been in English waters, but now projects are planned off Scotland. However objections have begun to emerge- and have attracted media attention. For example, US tycoon Donald Trump has criticised a proposal to build an 11 turbine offshore wind farm in Aberdeen Bay near his golf resort. He said he would use all legal means to oppose it.

Perhaps more significant have been the objections to the much larger project proposed by ScottishPower Renewables, who want to build a 180 turbine offshore windfarm 5km off the southwest coast of Tiree in the Hebrides. This ‘Argyll Array’, has met with strong local opposition. The No Tiree Array group want it put much further out. But that would be in deeper water, and need longer undersea grid links, adding substantially to the cost. . www.no-tiree-array.org.uk

Visual intrusion is obviously a concern when projects are near shore, but anti-wind project groups have also been moving on to economic viability: e.g. see http://wattsupwiththat.com/2011/08/22/britains-wind-farm-scam-threatens-economic-recovery/

BBC Radio News has been running a series on offshore wind, asking if they were ‘an expensive luxury’, which included coverage of Oxford Prof. Dieter Helm’s view that, while the government should invest in green power, offshore wind farms are far too expensive. www.bbc.co.uk/news/science-environment-14478226

The Daily Telegraph (14/6/11) made much of a National Grid report which noted that by 2020 it was expected that wind generation output might have to be ‘curtailed’ on about 38 days per year, because of excess production over need. The Telegraph commented ‘some experts believe this will cost almost £300m a year by 2020, with the cost passed on to consumers’. However tucked away at the end of the article was a quote from a grid spokesman, who said: ‘Over the past year we have had to reduce output from wind generators on 25 days, amounting to less than half of one per cent of the output of wind generation connected to the high-voltage transmission system over the same period.’ Moreover, new grid balancing, storage and load management techniques should improve e.g. wind forecasting techniques, making it easier/cheaper for gas turbines to load follow: www.nationalgrid.co.uk /Media+Centre/PressReleases/2011/25.05.11+wind+forecasting.htm

Even so, the Telegraph seemed convinced that wind power was a poor option It subsequently quoted from a new report from the Oxford Institute for Energy Studies which had concluded that ‘the maximum feasible level of wind generating capacity is 28 GW. At higher levels than this, the country faces the prospect of short notice intervention to reduce turbine output with the added complication that forecasts of wind speed beyond six hours into the future are inherently uncertain.’ The report commented ‘It would appear that the more ambitious targets for wind generation in the UK have been formulated without a full appreciation of the costs and complexities caused by the intermittency of very substantial levels of wind generation’.

In a more nuanced report from the Cambridge University Electricity Policy Research Group, Prof. John Newbery argues that the main economic problem is likely to be due to the support mechanism planned for future projects- the proposed variable-price market-based ‘Contracts for a Difference’ (CfD) system . He says that the CfD could lead to over £250m of electricity consumers’ money being wasted every year, and rising, as offshore wind develops. He argues that ‘a CfD on metered output will still leave basis risk and volatility risk (having to contract ahead of knowing actual output) on the wind developers, while a classic fixed FiT would transfer all those risks to an agency better placed to bear them, and at lower cost. The financial benefits of this risk reduction and reduced cost of capital for on-shore wind alone might together be £250m per year by 2020… and perhaps £70m p.a by 2020 for on-shore wind’.

There clearly are risks in developing new projects like off shore wind farms. The Crown Estate has just ended an agreement to buy the first 10MW Britannia offshore wind prototype from Clipper Windpower, after Clipper’s parent company, United Technologies Corporation (UTC), halted the project. It was to have been built in Newcastle.

However, it is not all bad news for offshore wind. Siemens, Vestas, Gamesa, GE and Doosan still plan to manufacture large offshore turbines in the UK. Moreover, there have been some very positive reports on environmental impacts. As the Guardian reported, a Dutch study has concluded birds avoid offshore wind turbines, while marine life finds shelter and new habitats, so that, overall, offshore wind turbines have “hardly any negative effects” on wildlife, and may even benefit animals living beneath the sea. The researchers studied a wind farm near Egmond aan Zee, off the Dutch North Sea coast.

Prof. Han Lindeboom from the Institute for Marine Resources and Ecosystem Studies at Wageningen University said ‘At most, a few bird species will avoid such a wind farm. It turns out that a wind farm also provides a new natural habitat for organisms living on the sea-bed such as mussels, anemones and crabs, thereby contributing to increased biodiversity. For fish and marine mammals, it provides an oasis of calm in a relatively busy coastal area’.

The researchers noted that the turbines help to protect schools of cod, and that porpoises are heard more often inside than outside the wind farm. The survey also concluded that sea bird species such as gannets tend to avoid the turbines, while seagulls appear unflustered and local cormorant numbers even increased.

The study noted that, depending on their position, offshore wind farms can contribute to a more diverse habitat and even help nature to recover from the effects of intensive fishing, pollution, oil and gas extraction, and shipping. But it recognised that the rotating blades can have a ‘disruptive impact’ on some bird species, and recommends that wind farms are located to minimise possible impact. http://iopscience.iop.org/1748-9326/6/3/035101

Meanwhile, the Guardian reported, with a major offshore wind programme planned, Germany, is looking to ‘soundproof’ offshore wind underwater construction sites to protect whales and porpoises in Baltic from the noise from pile driving- by installing pipes on the sea bed to produce a ‘bubble curtain’ to absorb the sound.

Posted by Dave Elliott on September 10, 2011 11:35 AM | Permalink