Author Mark Richards

The cost of offshore wind continues to fall – and by 2030 it has the potential to power 75% of the homes in the UK. Do we really need to continue with costly investments in nuclear power?

30 years ago this week Michael Fish famously presented the weather forecast on the BBC. “Good afternoon,” he started. “Early on today apparently a woman rang the BBC and said she’d heard there was a hurricane on the way. Well, if you’re watching, don’t worry, there isn’t.”

“The weather will become very windy,” he said, “But don’t worry, most of the strong winds will be over Spain.”

It was later described on the ITV news as ‘Southern England’s worst night since the war’ with millions of pounds of damage caused and – tragically – 13 people being killed.

Thirty years on…

Today, thousands of homes across the UK are again without power and commuters are being warned to expect chaos as – according to the tabloids – ‘Storm Aileen blasts in today’ and a ‘75mph hurricane is set to batter Britain.’

Leaving aside the small point that people in the Caribbean may now regard a 75mph wind as little more than a light breeze, Storm Aileen and her winds might not be all bad news. Thirty years on from Michael Fish’s understatement, the UK is rather more prepared for wind – and ready to make the most of it.

Offshore wind farms

You cannot have driven anywhere in the UK without seeing a wind turbine. They are now on seemingly every hill as landowners and local authorities look to generate clean renewable electricity. But by and large, onshore wind farms tend to be small: the really big ones are at sea, with Danish company Dong Energy recently announcing plans to build the world’s biggest offshore wind farm in the North Sea: the Hornsea Project 2 will be built 89km off the East Yorkshire and will create 2,000 jobs.

The wind farm will have a capacity of 1.4 gigawatts – a gigawatt is one billion watts, but if you paid as little attention in Science lessons as I did you will still be baffled. The real significance is that Hornsea Project 2 will have the capacity to power 1.3m homes in the UK, and will be operational by 2022, in just five years’ time.

Even more important than those numbers is the economics of the wind farm. Companies building wind farms receive a guaranteed price for the energy they will supply: the price is set at an ‘auction’ with the contract going to the lowest bidder. The strike price for Hornsea Project 2 is £57.50 per megawatt hour (MWh). What is a megawatt hour? According to the Clean Energy Authority, it is the amount of electricity used in an hour by approximately 330 homes (assuming they do not have teenage boys who are clinically incapable of turning a light off…)

offshore wind

The good news is that the strike price is 50% lower than the previous auction, held just two years ago, when offshore wind farm projects were receiving guaranteed prices of between £114 and £120 per megawatt hour. As wind farm technology continues to improve, so the price continues to come down: bigger turbines, higher voltage cables and lower cost foundations have all contributed to the falling price.

Emma Pinchbeck, from the wind energy trade body, Renewable UK, said the latest figure was “truly astonishing.” Matthew Wright, MD of Dong Energy in the UK described it as “Massive step forward for the industry. Hornsea will deliver low-cost, clean energy to the UK and high-quality jobs.”

Comparisons with North Sea oil

Michael Grubb, professor of energy policy at University College, London, called the latest cost reduction a “huge step forward in the energy revolution.” He said, “It shows Britain’s biggest energy resource – and least politically problematic – is available at a reasonable cost.”

He made the point that comparisons with the North Sea oil and gas industry were valid. “North Sea oil started off expensive,” he said. “But as the industry expanded costs fell. We can expect offshore wind costs to fall more too.”

So how many of our homes could wind farms power?

With the cost of ‘clean electricity’ coming down, how many homes in the UK could be powered in this way?

A recent report in City AM suggested that the UK could expand its offshore wind capacity to almost five times its current level by 2030, giving the potential to power 75% of all the homes. The report, commissioned by trade body WindEurope, estimated a total capacity of 25 gigawatts could be installed in UK waters, compared to the current level of 5.33 GW – enough to power more than 20m homes and see the UK retain its status as the world leader in offshore wind.

Looking further afield, offshore wind is expected to power 7 to 11% of Europe’s electricity demands by 2030 – although WindEurope said that was only a fraction of the potential power available from European sea basins.

Do we still need nuclear power?

Given the success – and falling costs – of offshore wind it is the obvious question to ask: do we still need to make a substantial investment of public money in the nuclear power industry?

‘No,’ says Caroline Lucas, co-leader of the Green Party. ‘Yes,’ say the representatives of the nuclear industry.

“This massive price drop for offshore wind is a huge boost for the renewables industry,” said Ms Lucas. “It should be the nail in the coffin for new nuclear. The government’s commitment to nuclear locks us into sky high prices for years to come. This should be the death knell for the Hinkley Point C nuclear station.”

Sky high prices? Given the falling cost of offshore wind, Ms Lucas has a point. While we are paying £57.50 per gigawatt hour for offshore wind, Hinkley C secured a subsidy of £92.50 per gigawatt hour – with that price due to apply for 35 years.

EDF Energy, who are building Hinkley Point C, said that the UK still needed a “diverse, well-balanced mix” of low-carbon energy. “New nuclear remains competitive for consumers who face extra costs in providing backup power when the wind doesn’t blow or the sun doesn’t shine,” they said. Giving a fine demonstration of wanting it both ways, they added, “There are also the costs of dealing with excess electricity when there is too much wind or too much sun.”

Too much sun? They have clearly never visited the coast of East Yorkshire…

One final question

I have often wondered as I have driven around the countryside or flown over an offshore wind farm: just how big is an offshore wind turbine? Showing there are no limits to our research I found an article in Windpower Monthly. Yes, there is such a magazine: please try and contain your excitement.

The article listed the ‘ten biggest wind turbines.’ Top of the charts is the MHI Vestas V164 9.5MW. This bad boy has a rotor diameter of 164m – not quite twice the length of a football pitch but not far off. There you are: in the world of the wind turbine, size really does matter…