Successive governments have hyped up the potential of SMRs, claiming they could “play an important role alongside large nuclear as a low-carbon energy source to support a secure, affordable decarbonised energy system”. The most recent support came yesterday (13 January) as Keir Starmer announced plans to “mainline AI into the veins of this enterprising nation”, with SMRs mooted as a potential solution to power electricity-hungry datacentres.
It could seem that they will play an important part in the government’s Clean Power 2030 target, which is under pressure from planning, supply chain and skills issues with just five years to go. But, speaking before yesterday’s announcement, experts told Professional Engineering that SMRs are not yet ready to be deployed, even though they could theoretically be built and deployed much quicker than conventional options.
“SMRs will not play a significant role by 2030,” said Matt Rooney, IMechE head of policy. “However, we expect the demand for low-carbon electricity to keep increasing into the 2030s and 2040s as transport and heat are increasingly electrified. Investments in technologies like SMRs and floating offshore wind are still important but they will have most impact beyond the 2030 target.”
As with SMRs, floating offshore wind turbines have received significant attention for their potential benefits over conventional options, including deployment in deeper waters and accessing higher wind speeds further from shore. But they too are unlikely to see significant deployment before the target for 95% clean energy in five years’ time.
“Other relatively new-generation technologies are unlikely to be deployed at significant scale,” said Frankie Mayo, senior energy and climate analyst at clean energy thinktank Ember. “However, with power demand forecast to rise beyond 2030, work is necessary now to develop technologies with longer timescales.”
With delays to these new sources, a less glamorous set of technologies could get much more attention in the coming years – batteries and long-duration storage.
As well as major investments in offshore and onshore wind energy and solar power, the Clean Power 2030 Action Plan also calls for 23-27 gigawatts (GW, thousand megawatts) of battery capacity (up from 5 GW).
The total battery storage pipeline far exceeds the 23-27GW target, said Barnaby Wharton, director of future electricity systems at trade organisation RenewableUK, with some planned projects representing 0.5GW of new capacity on their own.
“The great thing about batteries is they are really quick to deploy,” he said. “They can get through that planning and the connections process. I think we'll be able to see them come online in time for 2030 and they're going to play a really important role in managing the system, particularly with high [levels of] renewables.”
The Action Plan also targets 4-6GW of long-duration storage. “We've currently got half that, so we need to get more pumped hydro or liquefied air systems or projects on the system by 2030 – and that is going to be tight, but deliverable,” Wharton said.
“It's those individual and new technologies that we need on the system by 2030 that we need to really be focusing on. And that's why a lot of effort is going into it from the government.”
The cost of batteries has fallen by more than 90% in 15 years and is now around $65 per kilowatt-hour (kWh). “In terms of economics, it seems like that’s actually quite feasible and attractive,” said Stuart Bradley, principal engineer at the University of Warwick’s WMG.
Other promising options could include synchronous condensers and flywheels attached to the grid, he added. “We actually have a couple of really, really big flywheels in the UK down at Culham (in Oxfordshire); each one is 770 tonnes. Now if we repurpose those things, because Jet (Joint European Torus) has been closed down and decommissioned, we could get some tremendous grid support from those.”
Hydrogen is also a promising vector for excess wind energy, Bradley said, with potential to store it in geological deposits and use it in hydrogen-powered turbines.
“You could make aluminium – now that takes a lot of embodied energy,” he said. “Or you could just make steel as well. Of course, we'll have some electric arc furnaces soon as well. It's a really exciting time because we can see these opportunities – and, of course, the business opportunities as well – to lead the way and export those technologies.”
Other long-term energy storage could eventually include gravity-based technologies and compressed air storage, he added.
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.