Wind farms were considered a threat to national security:
It could have been the end for UK offshore wind.
Rune Rønvik made sure it wasn’t.
In 2000, the UK was facing an energy shortage. British oil and gas production was diminishing, coal-fired and nuclear plants were becoming obsolete, and demand for energy was spiralling. The government had to do something, fast. But there was one problem they’d overlooked.
After the millennium, European politicians set ambitious goals for improvements in energy efficiency, reductions in CO2 omissions, and a 20% increase in renewables—and in Britain, there were predictions of 70,000 new jobs in the new industry.
And like many other companies at the time, Equinor, then Statoil, saw an opportunity. It was a chance to build on our expertise as an energy company and to put a toe in the water of a new business area—offshore wind.
In 2007, planning for our £1 billion Sheringham Shoal offshore wind farm was well underway.
“It was a massive logistical project that took place offshore in quite demanding conditions, with 90 installations at sea,” says Rune Rønvik. Today, he’s Manager for Operations & Maintenance in Equinor New Energy Solutions—but back then, he was Project Director for the Sheringham Shoal project, just off the Norfolk coast.
Our Sheringham Shoal Offshore Wind farm was a massive logistical project in demanding conditions offshore, with 90 installations at sea
Rune Rønvik, Manager for Operations & Maintenance, New Energy Solutions, Equinor
Interest groups raised objections
As for all such projects, planning permission had to be sought and environmental impact assessments carried out. Objections were raised by local fishermen, ornithologists and air traffic controllers—but workable solutions were found for them all. Everything seemed to be on course for an approval by BERR, the Department for Business, Enterprise and Regulatory Reform.
A THREAT TO THE NATION’S SECURITY
But then, at the last minute, an official objection was received from the Ministry of Defence: the wind turbines would prevent defence radar from working. At stake: the air defences and security of the nation. The giant blades of the wind turbines would cause interference with the ground radar used to detect enemy aircraft approaching British shores at low altitudes, since their rotation can mimic the effect of fast-moving aircraft. The UK would be unable to protect and defend its airspace.
And just inland of the planned site for Sheringham Shoal, lay RAF Trimingham. Equinor’s wind turbines would block the radar’s view.
The rules were clear. Unless the MoD withdrew its formal objection, BERR could not issue consent to Equinor for the wind farm.
It was a severe blow to the Sheringham Shoal team—a showstopper with no apparent solution. And it wasn’t just Equinor's project—in the Greater Wash area, there were five other wind farms totalling 2.5 GW that were in the queue for consent, and still more further north.
There was anger in the British wind industry, with the MoD taking flak for hampering the progress of clean energy. The British Wind Energy Association (now RenewableUK) warned that wind farms, crucial for the UK to reach its renewable energy targets, were being held up by the planning process, while the MoD insisted that their objections were ‘absolutely essential.’
COMPANIES THREATENED LEGAL ACTION
The conflict resulted in delays, public inquiries and the withdrawal of some applications. Some companies began litigation proceedings, and at one point Prime Minister Gordon Brown had to intervene. The issue was becoming a public relations millstone for the MoD.
And for Rønvik and his team, it was a crisis. Although the objections applied to dozens of wind farm projects, Sheringham Shoal was first in the queue for planning permission—and time wasn’t on his side. His team of 40 was at a critical stage of the project, heading for Equinor’s crucial final investment decision in September 2008. The issue had to be solved and the MoD objection withdrawn before that deadline, or the entire project would be in jeopardy.
But then Rune Rønvik had an idea.
“There was talk of a regional or a governmental solution, but we didn’t have time for that. So, we decided to try to find a solution ourselves,” he says.
“We didn’t know how to get in contact with the MoD—we didn’t know where the doorbell was, so to speak.”
He approached BAE Systems, formerly British Aerospace, to get a better understanding of the problem—“to quantify how it looked from an MoD viewpoint.” BAE Systems were the leading suppliers of military radars to the Ministry of Defence—and they had a consultancy division.
“We hired them in in the first instance just to explain the problem to us. How could a construction only 135 metres high represent such a major threat?” recalls Rønvik.
the MoD needed to see fighters 500 km away
“We needed to be able to detect a fighter jet that had with a cross section size of only one square metre, 500 km away, but the wind farm had huge wind turbines only 30 km out to sea,” says radar specialist Dr Clive Jackson of BAE systems.
Rønvik was surprised when he saw how badly the radar images would be affected.
“We had to admit that the MoD had a case,” he says. “This was clearly an unacceptable situation for them,” he remembers. The wind farm created severe visual disturbance on the radar screen right up to an altitude of 10,000 metres (30,000 feet).
We needed to be able to detect a fighter jet only one square metre cross section in size, 500 km away, but the turbines were only 30 km away
Dr. Clive Jackson, BAE Systems
A ‘Photoshop filter’ for the radar
Rønvik decided to ask BAE to help find a solution. BAE suggested a software modification to the radar—a ‘wind farm mode’ that would filter out some of the noise using antennae and active signals.
“Software lowered the ceiling over the box,” says Jackson, describing how they managed to reduce the airspace affected by the interference. “We needed some firmware too—it was more than just filters. We used very specialised hardware that fired out electromagnetic pulses very rapidly and software that processed the signals in real time,” he explains.
The idea showed promise. If it worked, they might have a solution for mitigating the interference from the wind turbines.
Equinor sent a trial balloon to the MoD
With renewed optimism, Rønvik asked BAE to contact the MoD, since they already had the contacts and security clearance there.
“We sent in a trial balloon with BAE to the MoD, and they were extremely positive. They said we were the first developers who had acknowledged the extent of the problem, and who were also willing to contribute to a solution,” he recalls.
“In April 2008, the MoD got back to us and agreed to participate in a process to explore for a solution. After that we had exclusive access to them—they weren’t talking to any other wind farm developers. That’s because they wanted to see if this could be a template; a solution for resolving future conflicts between the MoD and developers,” he says.
And a solution was found: a new BAE radar on order for RAF Trimingham would be modified with the new software and firmware, reducing the impact area to about 1.6 km laterally and 2300 feet vertically.
There is a clear impact on radar from wind turbines, and in air defence particularly, we need primary radar coverage of non-cooperating aircraft.
Chris Knapman, former Deputy Assistant Chief of Staff of the Royal Air Force Air Command
The MoD subsequently lifted all objections to the wind farms under planning in the area, the developers committed to financing the radar upon their financial investment decisions, the TCE committed to finance the share for those wind farms that had not reached investment decision (which was all except Sheringham Shoal) and be paid back when they were sanctioned, and the DECC contributed towards the financing to reduce some of the burden for the developers and contribute to land the process successfully.
In 2012 the new radar was installed and commissioned at Trimingham, and the model from The Greater Wash has been applied later for other wind farm development areas further north the coast.
facts about sheringham shoal
- The wind farm meets the electricity demand for approximately 220,000 British households. Investments were £1 bn.
- Equinor is the operator of the wind farm
- The wind farm consists of 88 wind turbines standing on the sea bed spaced less than a kilometre apart, each generating 3.6 MW, making a total of 315 MW or 1.1 TWh annually
- Two 132 kV marine cables connect the facility to shore
- The turbine tower height is 80 metres, while the rotors are 51 metres long
- Sheringham Shoal became operational in the autumn of 2012
In January 2012, the MoD announced that contractor Serco had installed and successfully tested a new ‘windfarm-friendly’ Lockheed Martin TPS-77 Air Defence Radar.
Dr Gordon Edge, RenewableUK’s director of policy, hailed the news as “the end of what has been a long-term obstacle for the expansion of wind energy,” and in September 2012, Crown Prince Haakon of Norway conducted the official opening of Sheringham Shoal Wind Farm.
Although Sheringham has now been in operation for five years, the final chapter of this story wasn’t written until February 2016, when the MoD announced that Trimingham had achieved full operating capability and that they were satisfied that the solution provided “sufficient operational mitigation” for Sheringham Shoal. It was the first of five such TPS-77 wind farm radars that were to be installed in the UK.
Paving the way for Dudgeon
Nearly 10 years on, Rune Rønvik is modest of his achievements.
“It was a relief, as we had been looking for a solution to the radar problem for two years. It was big achievement for the wind farm industry as well as for the MoD because this problem with wind turbines and radar was going to happen all along the coast, and we managed to solve it,” he says.
It also paved the way for our next major development, the Dudgeon offshore wind farm, a few miles further out to sea, beyond Sheringham Shoal.