You’ll be hearing it up and down the UK: the future of nuclear power will be small and flexible. Of course, people have been claiming for years that small modular reactors (SMRs) are almost ready. Like so many technological breakthroughs, reality has lagged behind optimism.
Scale is not simply a matter of technical preference, as the heated debate over the Sizewell C proposal indicates.
Alison Downes is a campaigner for Stop Sizewell Sea, an organization attempting to put the brakes on a nuclear mega-project on the east coast of England. Like the controversial Hinkley Point C nuclear plant, Sizewell C will also be a two-reactor, 3.2-gigawatt power station. It will be located near the smaller Sizewell B plant currently in operation. According to the operator, EDF, Sizewell C will produce enough electricity for approximately 6 million homes. EDF hopes it will be operational in 2034, but construction has already fallen behind expectations.
Stop Sizewell C has several reasons to oppose the proposed Sizewell C plant. First of all, the project is expensive. The estimated cost is £20 to £30 billion, and the estimated expenditure is rising steadily.
Then there are ecological concerns. The plant will be established in a picturesque conservation area next to a bird sanctuary. Some people are concerned about coastal erosion. There are also uncertainties about the exact source of water that will be critical to the operation of the plant, which has led to legal challenges.
Compared to large-scale nuclear power in an ecologically fragile region, Downs argues that “there are alternative ways to make progress on our climate objectives”. He is in favor of cheap, rapid investment in renewable energy.
An alternative could simply be small-scale nuclear reactors, although these are also likely to be expensive methods of energy production compared to renewables. And there is ongoing debate over whether it will be possible for countries like the UK to go completely renewable given the dependence of wind and solar power on weather. (However, nuclear plants are also subject to downtime; in 2022, half of France’s nuclear fleet was offline.)
One advantage of SMR is public opinion: for example, Downs says SMR will face less opposition than the huge Sizewell C plant in Suffolk. The consequences on the coastal environment will be lower, as well as the costs. SMRs will be more portable and agile, gaining efficiency by being able to start and stop them more easily than huge, immovable power stations.
Yet Downs also believes that the massive Sizewell C project is politically popular partly because of its size. As she explains, “Any big infrastructure project creates jobs.”
The UK government is supporting nuclear energy in ways both big and small. At the launch of the Net Zero Nuclear initiative on 7 September, Andrew Bowie, UK Minister for Nuclear and Networks, said, “We have launched a nuclear energy revival in the UK with projects such as Hinkley and Sizewell C, as well as Great Britain.” “British Nuclear supports the latest cutting-edge technologies such as small modular reactors.”
Great British Nuclear is not an energy-focused reality show, but a young government entity that has started its work with the technical selection process for SMRs. It is expected that these will become operational in the mid-2030s. In other words, early SMRs may come online around the same time as Sizewell C, complicating the discussion about which will be developed faster.
Once they become viable, SMRs will be cheaper and faster to build, while using less fuel and producing less waste (although this is disputed). Nuclear waste remains a major concern for nuclear skeptics like Downs, given the almost unimaginably long time scale and uncertainty about exactly what to do with the material.
Of course, the trade-off is that SMRs will produce less power – about 1/3 the capacity of conventional large nuclear reactors. The sheer volume of energy supplies is undoubtedly important. Yet the conversation about scaling up nuclear power generation has lacked a parallel discussion on how to encourage energy consumption and energy conservation.
According to Hannah Ritchie, author of the Sustainability by Numbers newsletter, large-scale nuclear reactors typically take six to eight years to build – although there can be huge variations, with some overruns lasting decades. More than technical aspects such as reactor design, it is the political and economic situation that shapes these timelines.
As Ritchie says, a common reason why scale matters is this: “Big projects are riskier than small projects, and they give us far fewer opportunities to learn how to build them better”. .
Ritchie believes this is one of the reasons, “If there is to be a renaissance of nuclear fission technology, it is going to be modular… recent reactors have had bad press and long construction times. [certain] “The chances of countries returning are even slimmer.”
For now, the UK is hedging its bets by investing in both large (controversial) and small (non-existent) nuclear reactors. Other countries are looking to this corner of Europe for clues as to whether they too should increase or decrease their nuclear prospects.
Of course, this is not an either/or situation, as the UK’s diverse nuclear options suggest. But there are limits to both budget and political room for maneuver, as well as limited time to get the energy mix right as the climate changes for the worse.