Why You Should Care About Small Nuclear Reactors

Nuclear power could become a crucial feature in a world free of fossil fuels.

This is why Rolls-Royce secured financial backing from a consortium of private investors and the U.K. government to build small modular nuclear reactors capable of generating cleaner energy in the region, according to a press release from the company.

As of writing, roughly 16% of the United Kingdom's electricity comes from nuclear power, but this could start dropping soon. "A lot of existing reactors [in the U.K.] are nearing the end of their lifetime," said Professor Michael Fitzpatrick, Pro-Vice-Chancellor for Engineering, Environment, and Computing at the U.K.'s Coventry University, who's also an expert in nuclear energy, to Interesting Engineering. "We have to be replacing these just to stand still in terms of keeping nuclear at its portion of the electricity grid."

And, as more nations face the hard facts of solar and wind's intermittency issues, new investments in nuclear power like Rolls-Royce's small modular reactors could help the world balance the energy gaps left by renewables, and achieve net-zero carbon goals, on time.

Rolls-Royce's new SMR nuclear reactors will help the UK achieve its net-zero carbon goals

Following the roughly $260 million (£195 million) cash injection from private firms, in addition to the roughly $280 million (£210 million) from the U.K. government, the Rolls-Royce Small Modular Reactor (SMR) company was formally announced. And it could generate up to 40,000 jobs by 2050, according to a BBC report. Small Modular Reactors are essentially just like conventional ones; they use fuels like uranium to heat water, and then transfer that thermal energy into electrical energy, releasing only harmless steam (water vapor) into the atmosphere. But SMRs are tailored to suit any economic scenario. "SMRs allow you to do a mix where the endpoint is the same," said Fitzpatrick to IE. "The same ability to meet energy demands, but at different levels of commitment", both financially and in terms of scale. "It's a lower up-front cost, with a shorter build time."

In the release, Rolls-Royce SMR said one of its power stations would take up the space equivalent to roughly one-tenth of the space of conventional nuclear plants, and generate enough power to supply electricity to one million households. One SMR plant could generate 470 MW of power, which could be thrown into the mix of conventionally renewable power, like the more than 150 onshore wind turbines. Each SMR should cost roughly $2.7 billion (£2 billion) to construct, far less than the roughly $27 billion (£20 billion) needed to build conventional (full-scale) reactors. This lower cost makes SMRs a more viable alternative to fossil fuels, on similar financial standing as major wind and solar installations.

Solar and wind lack the means to store adequate power

Critics of the new investment in nuclear and the Rolls-Royce SMR business argue that the focus of the energy industry should be on renewable power, instead of new nuclear. But according to Fitzpatrick, this is a false dilemma. "The question of renewables and nuclear shouldn't be seen as an either/or," he said. "In the same way, we should be investing in many energy storage options, including hydrogen." Still, this raises the question: is nuclear really clean energy? It still produces toxic waste, and that's bad for the environment. But the kind of waste we see from nuclear power isn't driving a global climate catastrophe. "The waste is unpleasant stuff and it's potentially harmful," explained Fitzpatrick to IE. "But stacked against CO2, you're not really comparing like with like." The surge in global temperatures is directly linked to CO2 levels, which are drastically reshaping our atmosphere to the limits of human habitability, almost single-handedly thanks to fossil fuel industries.

"In other words, nuclear waste does not raise the same problem that fossil fuel pollution creates," said Fitzpatrick. And they also address a major issue with solar and wind power, which can't store enough power when there's no wind or sunlight. "Right now renewables suffer from intermittency. When wind speed drops, you need a gas turbine to cover" for wind turbines. "In the U.K. we've restarted coal fire plants to cover the gap. You need a way of storage for what's being generated by renewables (and we're no way near at the scale to do that)." It's difficult to overstate how serious this flaw in solar and wind can be on a practical level. "Would society accept on a calm still winter night that we should be prepared to do without heating in hospitals, or industry in general?" asked Fitzpatrick, rhetorically. The waste from nuclear power is also a flaw, but its effects don't tread water next to the ravages of excess CO2.

France, too, is investing in nuclear power

"Some people say you just can't store waste underground" like it's an absolute ethical principle, added Fitzpatrick to IE. "But carbon storage is exactly that; storing waste underground. And CO2 is the same forever. It has no half-life." The advantages of using nuclear often go unspoken because it simply hasn't shared the same spotlight that renewables have in the last decade or two. But "with nuclear, you're taking a tech that we know works, and investing it to deploy rapidly at scale." And the U.K. is not alone in realizing this.

On Tuesday, President Macron announced that France will build new nuclear reactors, specifically to meet global warming targets and keep energy prices under control, according to a Reuters report. This fits Fitzpatrick's rationale for emphasizing nuclear in national grids throughout the world. "If you're serious about making decarbonization commitments, you have to be investing in nuclear. We need a low-carbon baseload, and I think more governments are going to come to that conclusion, and I think that's going to drive a global nuclear renaissance." Right now, solar and wind power have already reached a serious limit, and it's one that was there all along: when the sun goes down, and the wind calms, there's not enough stored energy to keep an energy grid going. "Right at the moment the way we cover the intermittency gap is by using fossil fuels," said Fitzpatrick. But nuclear can fill these gaps, maintain energy levels, and it's just getting started. "Nuclear should not just be about technologies we have today, but also about the technologies we want to build in 30, 40, or 50 years."