UK dumps £2.5 billion into fusion pipe dream that's already cost millions

STEP sucked up £220 million in 2022, and it's still not apparent what that accomplished

UPDATED The UK government has just allocated another £2.5 billion to an ambitious fusion energy project without any indication it's progressed much beyond the planning stages.

The bundle of cash ($3.4 billion) will go towards the Spherical Tokamak for Energy Production (STEP) project planned for construction on the site of a former coal power station in Nottinghamshire, the government announced Thursday.

Tokamaks heat gases until they become plasma, then use powerful magnets to confine the ionized gas. Many experimental machines take the form of a torus – a cylinder with a central axis – and create a donut-shaped plasma loop of plasma. The plasma, which has a tendency to expand, is confined, super heated to increase the probability of collisions, and the boffins try to maintain high particle density to further increase the likelihood of collisions and thus induce a fusion reaction. Spherical tokamaks produce a narrower ring of plasma, more like a cored apple than donut. They are apparently more efficient, cost effective and stable than toroid tokamaks. The STEP prototype is just such a compact spherical tokamak, it will confine plasma gas in a tight magnetic field and use a deuterium-tritium fuel mix.

Fusion reactions produce a lot of energy – they literally make the Sun shine – and could potentially deliver a non-stop stream of clean power. Some might argue that solving the power generation and human pollution problem would be worth trillions to whoever could solve it.

The STEP prototype is planned to include some of the features of a power station, to showcase how a fusion power station will be operated and maintained.

Thursday's announcement marks the second cash injection the UK government has made in STEP - the first coming in 2022 along with the choice of Nottinghamshire to host the facility.

That first lot of funding saw the UK government allot £220 million to the project, meaning this latest investment is a 1,036 percent increase from that first bit of backing.

As for what STEP has done to encourage that added investment, that's anyone's guess - by all accounts it doesn't seem like a lot has happened with the project of late.

STEP's website describes its plans as being divided into three phases: The first, which involves concept design, organizational development, site selection, and regulatory approval.

"We now have a concept design for the powerplant," the STEP team noted on its website. "We also have a site."

Phase one was supposed to wrap up last year, with phase two involving securing planning consent and permission as well as program development, technology demonstrations and component manufacturing.

A couple of recent news items on STEP's press page indicate it's in the process of selecting industry partners for engineering and construction, and has begun collaboration with Seoul National University on the development of high-temperature superconducting magnet cables.

Phase three isn't scheduled to begin until the 2030s and will see construction of the actual STEP plant. The project's goal is to have the facility operational in 2040 "with at least 100MW of net energy demonstrated as soon as practicable," per STEP's website.

Fusion? Future.

"We are now within grasping distance of unlocking the power of the sun and providing families with secure, clean, unlimited energy," UK energy secretary Ed Miliband said during a recent visit to the UK Fusion Research Campus.

Grasping distance, maybe, but holding on is proving to be difficult.

The only known facility to achieve fusion ignition - the point at which the fusion reaction becomes self-sustaining - is the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) in California. The NIF has achieved ignition multiple times since first achieving it in 2022, and technically exceeded the amount of energy that went into the reaction chamber (2.04 megajoules from 192 lasers) by producing 3.15 megajoules of energy as a result. Unfortunately, powering those 192 lasers required 322 megajoules, meaning the reaction still didn't make up for the energy required to get it going.

Chinese researchers also reported a fusion breakthrough in early 2025 with nearly 18 minutes of plasma confinement in a tokamak - quite the achievement, but the researchers made no mention of how hot it was (fusion reactions don't start under 100 million degrees Celsius), whether there was a net energy gain, or anything else specific. European researchers later Indeed, extended China’s tokamak runtime world record by four minutes.

In other words, the UK's latest investment in the fusion dream is still betting on just that - a dream. We may be making advances toward fusion energy, but £2.5 billion is a big ask for a country buried in debt and a Chancellor of the Exchequer struggling to justify spending.

Updated June 13, 16:34 GMT: The folks at the private firm set up to handle the STEP project have been in touch to add some details to the story, including taking umbrage with our characterization of the £2.5 billion as being all for STEP.

UK Industrial Fusion Solutions' head of communications and engagement Ben Bradley told us in an email that the £2.5 billion was for fusion research and development, including funding for STEP, it would also allocate cash to UK Atomic Energy Authority and others.

“The likely STEP funding within this is likely to be less than half of that amount,” Bradley said. We note that the government’s Thursday press release announcing the funding describes it as going “to support the development of the world’s first fusion power plant,” so while it might not all be going right to the Nottinghamshire project, it’s all being spent toward that end.

Bradley added that the funding also shouldn’t be classified as a new investment since it “is simply confirmation of the required funding that has always been in our original business case,” and is being doled out “because the STEP programme is delivering on budget and on schedule.” Bradley said there have been no financial overruns, and that STEP is still on track to begin construction in 2029. The STEP team is currently demolishing the shuttered coal-fired power plant on the future fusion site and performing site characterization work to figure out where precisely STEP will be built, he said.

As for whether residents can still expect fusion to fuel their future by 2040, Bradley said it could be even earlier than that.

“We are [still on track] - though there are circumstances where this could be accelerated with the right technological advancements,” he spokesperson told us.

We'll remind readers the converse is also true, since no one has managed to make fusion actually work yet. ®