Wind turbines can disturb radar images and put both civil and military aircraft at risk, but research and development of mitigation measures is likely to cost between £5 million and £10 million, before the cost of new technology is rolled out. Who is going to pay is a question currently taxing the wind industry.
Half of all British wind farm proposals are now stymied by civil and military aviation authorities concerned about the radar problem: construction of more than 4.5 GW of clean power capacity is stalled at the starting gate. All parties are working to find a solution to the impasse. The stakes are high-and not only for the industry. The government's carbon reduction goals are in danger too.
The 4.5 GW of stymied development includes both onshore and offshore projects which are crucial to the UK meeting its 2020 renewable energy targets. Furthermore, no one yet knows the affect that objections from aviation interests may have on the huge volume of wind capacity to be developed in the new offshore strategic areas being formally identified around Britain's coast. These areas will house wind farms to be built under the country's third and largest round of offshore site leasing.
The bulk of aviation objections come from NATS En Route Ltd (NERL), the body responsible for civil air traffic throughout the UK's airspace. The rest comes from the Ministry of Defence (MoD) which operates military radar, and from airports. Although dialogue between the British Wind Energy Association (BWEA) and aviation bodies has been ongoing for years, a breakthrough came at the end of last year after Prime Minister Gordon Brown ordered the government ministers involved to "step up their efforts" to find solutions.
In June, the BWEA, NERL, Civil Aviation Authority and the government departments for defence, business and transport signed up to an "aviation plan." According to the plan there is no single solution that will allow wind turbines to co-exist safely with aviation radar. A series of technical fixes is needed.
The plan lays the basis for a co-ordinated approach to a series of tasks. These include defining the performance criteria of radar in the presence of wind farms, technical solutions to reduce the effects of wind farms on air defence and air traffic control radar, and development of "stealth" or radar absorbent turbine technology. Most of the funding for the work is expected to come from the wind industry.
The BWEA's Nicola Vaughan says the Department of Business, Enterprise and Regulatory Reform (BERR), the MoD and the Technology Strategy Board have already committed £2 million. The rest will have to be paid for by wind project developers. "It is going to come from their bottom line," she says, adding that the funding needs to come quickly. "We cannot wait any longer."
BWEA is putting together a case to make it attractive for developers to invest in solving the problems, Vaughan says. Additional funding from government, which has an interest in seeing its targets met, and from other stakeholders is hoped for. One of these is the Crown Estate, the owner of most of the UK seabed, which will earn considerable income from leasing sites for offshore wind farms.
A key task is the "Raytheon" project to mitigate the effect of turbines on NERL's en-route radar across the country. Over half of the 4.5 GW of wind currently on hold is blocked by objections from NERL. Canadian firm Raytheon is supplying NERL's entire new fleet of en route radar and the wind industry is working with the company to develop enhancements to avoid the risk of wind turbines disturbing radar images. It is further understood that NERL is pushing for the mitigation software to be incorporated on its whole fleet -- with the wind industry footing the bill.
For now, BWEA is sticking to its guns, saying the technical fix should only be fitted to those radar that are affected by wind farm developments. The usual procedure is for the wind farm in question to foot the bill. A grey area, however, will be where a number of generators are affected by a single radar, such as NERL's en route radar at Lowther Hill in Scotland. But in most cases, mitigation solutions are specific to the wind project and are developed on a bespoke basis between the radar operator and wind farm developer, which pays.
Signs of light
Although it is early days for the aviation plan, Vaughan sees signs of progress. BERR appears to be taking a more pragmatic approach to determining wind farm applications -- in some cases avoiding delays which planning inquiries inevitably cause and the resulting huge legal bills. This summer, the government department granted consent to two projects -- Middlemoor on land and Sheringham Shoal offshore -- leaving it to the developers to agree mitigation solutions with the MoD.
Vaughan, meanwhile, is receiving reports that new projects are receiving a faster response from the MoD to their initial consultations. "Over the past two months I have had some great feedback from developers saying they are getting a quick turn around," she says. We are starting to see some movement and the MoD are making some good progress."