Revival of interest in nuclear power gives hope to start-ups
Investment in both fission and fusion suggests attitudes are changing
Forty years since the meltdown of Reactor 4 in the Ukrainian town of Chernobyl in 1986, the world is experiencing what analysts have called a “nuclear renaissance”.
Targets to reach net zero carbon emissions coupled with the ever-increasing power demand from data centres have prompted Morgan Stanley to predict that global nuclear capacity will more than double by 2050 and that investments in the nuclear value chain will reach $2.2tn.
Meanwhile, executive orders signed by US President Donald Trump have committed to expanding American nuclear energy capacity from 100 to 400 gigawatts by 2050, and to having 10 new large reactors with complete designs under construction by 2030.
“Trump’s executive orders tear down decades of sclerosis in the nuclear sector in America. It was the firing gun for what some people are calling the nuclear renaissance,” says Will Dufton, a partner at venture capital firm Giant Ventures in London.
In Europe, too, attitudes towards nuclear energy are changing. Nuclear power already generates roughly a quarter of the bloc’s total energy and half of its carbon-free power. In 2023, the Nuclear Alliance of Member States set a target of 150GW of nuclear capacity across the EU by 2050 in a push for cheaper, cleaner power and energy sovereignty.
Dufton joined Giant Ventures in 2024 to lead second-round investment in start-ups in Europe and the US that were looking to scale up, and immediately began looking at the nuclear sector. “I felt like there was a shift happening, spearheaded by AI. The US is in a race against China to get to artificial intelligence supremacy, and energy is the bottleneck,” he says.
Giant Ventures led the investment into Los Angeles-based Radiant, which manufactures one-megawatt nuclear microreactors for use by the US military in remote locations. In May 2025, Radiant raised $165mn in third-round funding and six months later an additional $300mn, bringing its total value to more than $1.8bn.
“We got very lucky,” Dufton says of the deal.
For decades, nuclear innovation has been held back by the historic disasters in the sector: Chernobyl, in 1986, and Fukushima, in 2011. But more recently, the wars in Ukraine and Iran have forced fossil fuel prices up and disrupted energy supply chains, pushing governments towards reliable, low-cost sources of energy and to reconsider nuclear power.
The UK government, for example, promised in March to speed up the construction of nuclear power stations, following recommendations in a review by John Fingleton, former head of the Office of Fair Trading.
The Radiant deal is just one example of where geopolitical shifts are filtering down into nuclear technology and innovation. TerraPower, founded by Microsoft co-founder Bill Gates, has raised $1.7bn with backers including chip giant Nvidia. The company is making small modular nuclear reactors (SMRs), which are easily transportable and designed for use in the field.
But while SMRs are attracting considerable investment, they still produce nuclear waste and are yet to be tested at scale, or tested at all outside war zones. These, and all nuclear power plants, use nuclear fission — the splitting of a heavy, unstable atom into smaller ones — which carries the risk of the reaction getting out of hand (as in Chernobyl).
Meanwhile, nuclear fusion is also attracting European and American venture capital investors. The process, where two light atoms combine to form a heavier one, poses no risk of meltdown and produces no radioactive waste.
Supporters of nuclear fusion say it is a theoretically totally limitless and safe energy source. Yet if it becomes a reality, it would be decades in the future and the technology is, at present, unproven.
That has not stopped investors. Founded in 2023, German start-up Proxima Fusion has raised €200mn to build a Stellarator Model Coil (SMC) in 2027, the first step towards building a functioning fusion power plant.
Another company, Helion Energy, raised $425mn in a late stage funding round last year from investors including SoftBank and OpenAI’s Sam Altman.
“There was always this strong backlash against fission, which was politically driven, but fusion seems like the Holy Grail: clean and abundant energy,” says Sebastian Becker, general partner at Redalphine, a European venture capital firm that was a seed investor in Proxima Fusion.
While Europe and the US pour money into the sector, China is estimated to have spent as much as $6.5bn on commercially viable fusion projects since 2023 alone.
“China is building fusion cities, entire cities focused on developing this technology,” says Peter Roos, chief executive of Novatron Fusion Group in Stockholm. “They are pushing the limits. They don’t have the technology yet but they are definitely doing all they can to make it happen. They want to be the first.”