Britain could scrap the $23-billion (£18-billion) nuclear power plant at Hinkley Point and get the same amount of electricity from offshore wind turbines for roughly the same investment.

That’s the assessment of Bloomberg New Energy Finance following Prime Minister Theresa May’s decision to review whether to proceed with the first new atomic plant in more than three decades. For the same capital costs, the UK could install about 830 new turbines at sea, which would generate 25 terawatt hours a year – the same amount of power the Hinkley reactors would produce, according to the London-based researcher.

The findings add to the debate over whether Electricite de France’s (EDF’s) proposal makes economic sense. With the cost of offshore wind turbines falling, developers led by Dong Energy of Denmark are promoting renewables as a better way to get energy without the emissions that cause global warming.

“If we had £18-billion to spend today, we could build 5.7 GW of offshore wind – just under double the capacity and generating the same level of power as Hinkley Point,” said Keegan Kruger, analyst for BNEF.

The BNEF assessment includes only the capital cost of erecting various forms of generation, not operating expenses or the price of fuel. It also sidesteps the question of what would have to be invested to create storage at a giant scale capable of smoothing out power delivered from renewables when the sun isn’t shining and the wind isn’t blowing.

“Hinkley Point C is competitive with all other forms of low-carbon electricity generation,” a spokesman for EDF said by email. “The price of £92.50 per megawatt hour for Hinkley Point’s output compares with an average of £123 per megawatt hour for renewable schemes in the early 2020s without including the extra costs of their intermittency. Recent contracts for offshore wind were agreed at an average of £137 per megawatt hour.”

Government Review
May’s surprise decision last month to review whether to build the Hinkley Point reactors overlooking the Bristol Channel reopened the debate on whether nuclear power represents good value for consumers, who will pay EDF billions of pounds in subsidies to operate the plant for 35 years.

Hinkley would provide power for six-million UK homes at a time when other nuclear reactors are being retired and coal plants are shutting, raising the need for more generators to feed the UK electricity grid.

Matching Hinkley’s 3.2 GW of electricity output with renewables would require wind turbines and solar panels with a much higher capacity, since those forms of clean energy don’t work at night or when there’s no breeze. Nuclear, by contrast, is classed as ‘baseload’ energy, generating 90% of the time it’s switched on.

Since offshore wind farms generate only about half the time, Britain would need double the capacity to deliver the same amount of power as Hinkley, Kruger said. Batteries or hydroelectric storage would also be needed for days when the wind doesn’t blow.

The renewables industry sees the potential demise of Hinkley as an opportunity. Dong, the world’s biggest offshore wind farm installer, has already said it is prepared to step in and build more projects should Hinkley be scrapped. Huub de Rooijen, director of energy at The Crown Estate, which leases out areas of the UK seabed for offshore wind farms, also said the technology could grow in place of Hinkley.

“We have an inexhaustible supply of reliable and clean power right on our doorstep,” he wrote in an article for the Guardian on Sunday.

Kruger said offshore wind farms could be built faster than Hinkley, which, EDF says, could be built within a decade after it gets the final go-ahead. “Not only can we build additional offshore wind capacity for the same level of investment, but we may also create more local jobs,” he said.

If Hinkley were replaced, the cheapest option upfront would be power stations fired by natural gas, according to Janis Hoberg, an analyst at BNEF. Building 3.6 GW of new gas capacity would produce 25 terawatt hours a year and would cost less than £3-billion, compared with the £18-billion required for Hinkley.

Yet using gas would jeopardise Britain’s effort to cut carbon emissions, and the cost of buying fuel would be higher than nuclear, he said.

Onshore Wind or Solar?
Installing wind turbines on land would be even cheaper than placing units offshore, BNEF found. Matching the energy created by Hinkley would require about 3 000 new onshore wind turbines built across the UK. That would cost about £11-billion, compared with Hinkley’s £18-billion.

Onshore wind would conflict with a ban on support for new offshore wind brought in by May’s predecessor, who said some wind towers were a blot on the landscape.

Offshore wind, by contrast, has a stronger backing by the Conservative government. Former Energy Secretary Amber Rudd said 20 GW could be installed by 2030, and the government is planning to this year host the first of three auctions designed to spur the technology. Greg Clark, the current Business and Energy Secretary, gave approval this month to Dong Energy’s 1.8 GW Hornsea Project Two offshore wind farm in the southern North Sea, which will be the biggest facility of its kind once completed.

Matching the energy output of Hinkley with solar power would actually prove more expensive than nuclear and require covering an area equivalent to the cities of Birmingham and Edinburgh in solar panels, BNEF found.

It would cost £19.4-billion to install the 80-million solar panels required to generate 25 terawatt hours a year. That would cover 48 000 ha of land.
Even if swathes of land were given over to photovoltaic panels, replacing nuclear with solar is technically impossible without massive storage batteries, because the UK isn’t very sunny.

“Even if there were no constraints to land and building a solar farm equivalent to Hinkley’s production was feasible, the UK would need to shut down when the sun is not shining, and that would be too many days,” said Lara Hayim, a BNEF analyst.