Image copyright Getty Images Image caption Experts say the government should be frank about the inter-dependence of civilian and military nuclear

Energy bills in the UK are inflated partly because households are subsidising nuclear submarines, MPs have been told.

Experts think one government motive for backing civilian nuclear power is to cross-subsidise the defence industry.

They say nuclear power is so expensive that it should be scrapped in favour of much cheaper renewable energy.

Others argue that nuclear still plays a key role in keeping on the lights, so the military aspect is not significant.

But in evidence to MPs on the Business Select Committee, researchers from the University of Sussex said the government should be frank about the inter-dependence of the civilian nuclear programme and the nuclear defence industry.

Supply chain

Prof Andy Stirling from Sussex argues that one reason the government is willing to burden householders with the expense of nuclear energy is because it underpins the supply chain and skills base for firms such as Rolls Royce and Babcock that work on nuclear submarines.

He said: “It is clear that the costs of maintaining nuclear submarine capabilities are insupportable without parallel consumer-funded civil nuclear infrastructures.

Image copyright EDF Image caption The government gave its approval for the Hinkley Point C nuclear power station in 2016

“The accelerating competitiveness of renewable energy and declining viability of nuclear power are making this continuing dependency increasingly difficult to conceal.”

Rolls Royce, which makes reactors for nuclear submarines, has been pressing the government to agree a fleet of small modular reactors for power generation in the UK. This civilian technology would be transferable to submarines.

'Persuasive' evidence

A spokesperson for the Department for Business, Energy & Industrial Strategy (BEIS) said: "We believe having a diverse energy mix is the best way of ensuing energy security while allowing us to meet our climate commitments.

"Nuclear has an important role to play as we transition to a low-carbon economy, but as with any technology, it must represent good value for money for the taxpayer and consumer."

A committee source told BBC News the researchers' evidence appeared persuasive and well-researched.

The committee is expected to release the evidence in coming days as it prepares to discuss whether the UK really needs nuclear power for energy security.

The debate has taken on greater significance as the true costs of nuclear power have been revealed.

It was once forecast that nuclear energy would be too cheap to meter. But it's clear now that bill-payers will give price support to the Hinkley Point C nuclear station at a cost of £92.50 per megawatt hour, compared with the cheapest agreed future subsidy of £57.50 for offshore wind.

Ministers expect that, before long, wind energy will operate without support.

Prof Stirling says the issue of nuclear inter-dependence is addressed openly in the US.

In 2017, the former US Energy Secretary Ernest Moniz (a nuclear scientist) said: “A strong domestic (nuclear) supply chain is needed to provide for Navy requirements. This has a very strong overlap with commercial nuclear energy.”

Prof Stirling told BBC News: "We need this sort of transparency in the UK."

Catch-22

But the government faces a Catch-22 situation on this issue.

If it continues to decline to admit the inter-dependence of civil and military nuclear, it will stand accused of hiding a self-evident truth.

But if it accepts that decisions on nuclear power are influenced with half an eye on manufacturing jobs and nuclear deterrent, it will face resistance from consumer groups unwilling to cross-subsidise submarines.

The MPs’ hearing is timely, as the government will shortly publish an energy white paper outlining how the UK will supply electricity in a zero carbon economy.

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