Despite recent scrapping of three plants, experts still feel the energy has stake in future

Ever since Tony Blair rebooted support for nuclear power 13 years ago, British governments have been committed to a new generation of reactors to secure supplies and cut carbon emissions.

However, those ambitions have yielded only one project under construction, Hinkley Point C in Somerset, south-west England.

The past two months have dealt serious blows to hopes for more, with Toshiba abandoning its plans for Moorside in Cumbria and Hitachi scrapping its Wylfa plant on Anglesey. Wylfa’s death means a second Hitachi plant planned for Oldbury, Gloucestershire, is doomed, too.

Together the three projects would have provided 15% of today’s electricity demand.

That begs the question: is it time to rethink plans for new nuclear or redouble our nuclear efforts? With the cost of wind, solar and batteries dropping rapidly, have renewables and smart technologies matured enough to fill the gap?

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What is not in question is the UK’s need for more low-carbon power. Coal and old nuclear plants are shutting in the 2020s and tough climate targets are looming.

The Green party and groups such as Greenpeace advocate ditching nuclear in favour of more renewables, energy efficiency and flexibility through imports, batteries and other technologies.

However, most energy industry experts think the future involves some new nuclear. The government has already restated its commitment to new nuclear power.

“It’s difficult to see a low-carbon energy system in the future which has no new nuclear,” says George Day, the head of policy and regulation at the government-funded Energy Systems Catapult.

“If you try to rely on just renewables and storage, without carbon capture and storage or nuclear, you are looking at a very challenging transition and one that is more costly than a balanced mix [of supplies].”

All of National Grid’s four future energy scenarios envisage some new nuclear, although the amounts differ considerably.

Peter Atherton, an analyst at Cornwall Insight, said it was hard to imagine an energy system without the baseload power – or continuous electricity supply – provided by nuclear.

“There is a school of thought that says baseload is a 20th century thing. They might be right – but it would be a big call by government to bet baseload won’t be a thing by 2025.”

The government has already downgraded the amount of new nuclear it expects to be built in the future. It assumes 13 gigawatts of new nuclear capacity by 2035, implying three further nuclear power stations in addition to the 3.2GW plant at Hinkley.

Facebook Twitter Pinterest The Hinkley Point C nuclear power station under construction near Bridgwater, Somerset, England. Photograph: Matt Cardy/Getty Images

There are now only two firms in the running, which are both involved in plans for two new plants.

French state-owned EDF Energy, which is behind Hinkley, wants to start building a carbon copy of that project at Sizewell, on the Suffolk coast, in 2021. Chinese state-owned CGN, meanwhile, is accelerating work on a Chinese-designed reactor for Bradwell in Essex, with the aim of being operational around 2030.

Hitachi’s withdrawal suggests the financing model used for Hinkley, and proposed for Wylfa, is dead. The government will likely junk that approach – of offering a guaranteed price of power for 35 years – for an alternative known as the “regulated asset base” (RAB) model.

The Department for Business, Energy and Industrial Strategy has created a whole division to develop RAB, where a regulator would set a fixed sum for the power station’s costs and fixed returns for the developer, paid for by energy billpayers or taxpayers. Officials are assessing RAB’s viability, with a decision expected this year.

But critics say the approach loads the risk of nuclear plant construction delays, such as those seen in France and Finland, on citizens. Returns would also be paid for years before any electricity was generated.

EDF Energy backs the RAB model and the Chinese have said they would look at it. The influential government adviser Dieter Helm, professor of energy policy at Oxford University, has called it “plausible and preferable” to the Hinkley approach if the UK wants new nuclear. Day believes it could produce the power stations that ministers want.

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Labour, which is pro-nuclear, has branded the approach risky and reckless but has not put forward an alternative.

Given the uncertainty over new nuclear, could the UK manage without it? Maybe. The obvious route is a lot more renewable power capacity than currently planned.

The government’s climate change advisers last year hiked up the amount of renewables they expected four years ago, to 45-60% of electricity supplies by 2030, up from 40-55% previously. Both are a big increase from the 33% level today.

The Committee on Climate Change said there is evidence the energy system could cope with as much as 60% of supplies coming from intermittent renewables.

Filling the 9.2GW-sized hole left by Moorside, Wylfa and Oldbury would require 14GW of offshore wind power, according to the Energy and Climate Intelligence Unit thinktank. That is equivalent to more than 20 of the world’s biggest offshore windfarm, which consists of 87 turbines.

According to Atherton, the only way renewables and storage could plausibly fill the nuclear gap would be to “spend a vast amount of money on saturating the UK with offshore wind”. That could end up with enough turbines in enough different locations to replicate the “always-on” nature of nuclear.

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Large-scale batteries will help with the variable nature of renewables and are expanding fast. But they will not address the fact that electricity demand is much higher in winter than summer, or solve long windless spells.

The other big techno fix in the arsenal of low-carbon energy options is carbon capture and storage (CCS). However, many years of government efforts to kickstart it failed and ministers have switched their focus away from CCS for power stations to CCS for industrial uses.

Day said gas power stations with CCS still looked “pretty promising” but significant policy changes would be needed to enable firms to invest in it.

Others, however, are more dismissive. Atherton said: “People have been working on CCS gas for 20 years and nobody has got within a mile of it yet. People will tell you the technology works … that doesn’t mean I can do it on a budget.”