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SMRs may not be the holy grail for energy security, net zero

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It’s possible to achieve both energy security and the UK’s climate goals without blowing the budget on next-gen nuclear technologies, according to Andrew Warren.

Electrical Review covered in-depth the array of announcements that were made during the Spring Budget, but there was arguably one announcement above all that was most pertinent to the net zero drive. That was when Chancellor Jeremy Hunt reconfirmed – for the fifth time – that the Government intends to create a new Great British Nuclear agency. 

It is a name that of itself may bring comfort to all those living on the nuclear-free island of Ireland.

So what will this agency do? Well, the Chancellor explained that, when launched, it will run a competition this year for the UK’s first Small Modular Reactor (SMR). The plan is for it to eventually award £1 billion in co-funding to a winner to build out an SMR plan.

This competition has some distinct echoes. Back in March 2016, the Government launched a competition to identify the best value SMR design for the UK. To the best of my knowledge, nobody has ever claimed that prize, of £250 million.

This re-announcement prompted me to consider the background to this Budget announcement.

It comes at a time in which private sector funding for larger nuclear power stations is proving to be extremely difficult. There is a lengthy list of large pension funds that have publicly refused to get involved with providing capital for the hapless Sizewell C pressurised water reactor project in Suffolk. Meanwhile, European Commission President Ursula von der Leyen is rumoured to be promoting the inclusion of SMRs within the European green investment taxonomy, whilst simultaneously excluding pressurised water reactors which make up most of the existing nuclear fleet.

So, if SMRs are the current political flavour of the month, how have we reached this position when there is still no formal approval of the technology from regulators, let alone practical evidence of how it can operate in the real world?

In January, the UK Government announced that six SMR vendors had applied for their designs to be formally assessed with a view to commercialisation in Britain. The companies have joined a much publicised Rolls-Royce-led consortium and will be subjected to an assessment process carried out by the UK’s Office of Nuclear Regulation (ONR), which will look in exhaustive detail at reactor designs proposed for construction.

Designs that successfully complete the Generic Design Assessment (GDA) – which is expected to take between four and five years – will then be ready to be built anywhere in the country, subject to meeting site-specific requirements. 

Why do we need new reactor designs? 

Recent results of orders placed for larger nukes are uniformly poor, with reactors invariably late and over budget. Some of the worst cases, notorious projects in Olkiluoto, Finland and Flamanville, France, have seen construction periods of 18 years and costs of three to four times above the expected level.

So, SMRs are being increasingly seen as the new saviours for the nuclear industry. This category embodies a range of technologies, uses and sizes, but relies heavily on features that were the selling points for larger designs. They are smaller than current stations which produce 1,200MW to 1,700MW of electricity. Instead, sizes range from 3MW to about 500MW. The Rolls-Royce design is a 470MW pressurised water reactor, which is bigger than one of the reactors at Fukushima in Japan that suffered serious damage in the 2011 tsunami.

These advanced designs are not new – sodium-cooled fast reactors and high temperature reactors were built as prototypes in the 1950s and 1960s – but successive attempts to build demonstration plants have been short-lived failures. It is hard to see why these technologies should now succeed given their poor record.

A particular usage envisaged for some of the technologies is production of hydrogen. However, as Professor Stephen Thomas of Greenwich University recently pointed out to me, to produce hydrogen efficiently, reactors would need to provide heat at 900°C. This, he said, is “a temperature not yet achieved in any power reactor, not feasible for a pressurised water reactor or boiling water reactor and one that will require new exotic and expensive materials.”

Developers of SMRs like to give the impression that their designs are ready to build, the technology proven, the economic case established and all that is holding them back is Government inactivity. However, taking a reactor design from conception to commercial availability is a lengthy and expensive process taking more than a decade and certainly costing more than £1 billion.

How can the economics of SMRs be tested?

The main claim for SMRs over their predecessors is that being smaller, they can be made in factories as modules using cheaper production line techniques, rather than one-off component fabrication methods being used at Hinkley Point C. The idea is that the module would be delivered to the site on a truck essentially as a ‘flatpack’. This would avoid much of the on-site work which is notoriously difficult to manage and a major cause of the delays and cost overruns that every European large reactor project suffers from.

However, any savings made from factory-built modules will have to compensate for the scale economies lost. A 1,600MW reactor is likely to be much cheaper than 10 reactors of 160MW.

And it will be expensive to test the claim that production line techniques will compensate for lost scale economies. The first reactor constructed will need to be built using production lines if the economics are to be tested. But once the production lines are switched on, they must be fed. Rolls-Royce assumes its production lines will produce two reactors per year and that costs will not reach the target level until about the fifth order. So, if we assume the first reactor takes five years to build, there will be another nine reactors in various stages of construction before a single unit of electricity has been generated from the first, and the viability of the design tested.

This could mean that perhaps about 15 SMRs will need to be under construction before the so-called ‘nth of a kind’ settled-down cost is demonstrated. But once the initial go ahead is given, there will be pressure on the Government to continue to place orders before the design is technically and economically proven, so the production lines do not sit idle.

It will not be sufficient for SMRs just to be more economic than large reactors. SMRs will need to be competitive with low-carbon technologies such as wind and solar technologies and energy efficiency measures, all of which large reactors compare poorly with.

Will SMRs be a major contributor to meeting the UK’s climate change targets?

The selling point for nuclear power is that it is a relatively low-carbon source of power that can replace fossil fuel electricity generation in the UK and elsewhere. However, by the time SMRs might be deployable in significant numbers, realistically after 2035, it will be too late for them to contribute to reducing greenhouse gas emissions. Electricity is acknowledged to be the easiest sector to decarbonise. If the whole economy is to reach net zero emissions by 2050, then this sector will have to reach that point long before then, probably by 2035. So SMRs appear to be too little, too late.

There is also a fear that SMRs will create more waste than conventional reactors, according to a study recently published in Proceedings of the American National Academy of Sciences. The research notes that SMRs would create far more radioactive waste, per unit of electricity they generate, than conventional reactors by a factor of up to 30. Some of these smaller reactors, with molten salt and sodium-cooled designs, are expected to create waste that needs to go through additional conditioning to make it safe to store in a repository.

And yet, despite the past failures of nuclear power and increasing public scepticism, there remains an appetite within the British Government to give the nuclear industry one more chance.

It remains to be seen whether the Government follows its instinct to continue supporting the sector or whether the amount of public money at risk makes such a decision politically impossible, given the massive underwriting these projects require by consumers and taxpayers.

Nuclear’s specious claims

The claims being made for SMRs will be familiar to long-time observers of the nuclear industry: costs will be dramatically reduced; construction times will be shortened; safety will be improved; there are no significant technical issues to solve; nuclear is an essential element to our energy mix.

In the past such claims have proved hopelessly over-optimistic and there is no reason to believe results would turn out differently this time. Indeed, the nuclear industry may well see itself in this ‘last-chance saloon’.

The risk is not so much that large numbers of SMRs will be built; it is my belief that they won’t be. The risk is that, as in all the previous failed nuclear revivals, the fruitless pursuit of SMRs will divert resources away from options that are cheaper, at least as effective, much less risky, and better able to contribute to energy security and environmental goals. Given the climate emergency we face, surely it is time to finally turn our backs on this failing technology.

Andrew Warren is a former special advisor to the House of Commons environment committee. Special thanks to Greenwich University’s Professor Stephen Thomas for his advice for this piece.

Andrew Warren

Chairman of the British Energy Efficiency Federation

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