U.S. enrichers cover 7% of a nuclear quadruple target, and the clock is ticking

Antares made it to the finish line in June, successfully flipping the switch on its Mark-0 microreactor. This wasn’t just a nice engineering win. It was first to the finish line in the Trump administration’s pilot program race, with a July 4 deadline for the next generation of reactors to achieve criticality.

Now here’s the uncomfortable part: even if reactors accelerate, the nuclear fuel supply chain does not magically scale at the speed of press releases. The U.S. is on the verge of a potential “second nuclear age,” and projects are multiplying to power the AI boom. But nearly the entire North American nuclear fuel supply chain is “woefully lacking,” from uranium mining to fuel-pellet fabrication. Add the policy schedule, and the timeline gets sharper: Congress bans imports of enriched uranium in 2028 from Russia, which dominates the industry. For executives betting their capital on reactor schedules, that means the bottleneck may show up not at the reactor gate, but upstream, in fuel.

Fortune lays out the uncomfortable math of uranium dependence and timing. Roughly 98% of the uranium consumed by U.S. reactors is imported. That includes not just the ore and processing steps, but the whole conversion and enrichment pipeline that turns “yellowcake” into the enriched uranium fuel that reactors actually use. A uranium mine opening is a long-lead operation, not a procurement exercise. Cameco president Grant Isaac told Fortune that bringing a new mine online can take 15 to 20 years. His core concern is classic industrial mismatch: reactor construction timelines are shorter than the timelines required to find, permit, construct, and commission new uranium mining capacity.

The U.S. nuclear capacity target makes the mismatch worse, because growth would be huge. The White House’s goal is to quadruple U.S. nuclear capacity from about 100 gigawatts today to 400 gigawatts by 2050. Fortune notes that is framed as enough to power almost 300 million homes, though for context there are about 150 million homes in the entire country today. Even if those targets come in below ideal, unprecedented growth is still anticipated in the coming decade. And a lot of nuclear fuel will be consumed along the way.

This is where the “race” metaphor gets real. Building reactors is one challenge, but fueling them is another, and the fuel chain has multiple choke points. Fortune summarizes the process as a sequence: uranium ore is mined and milled into yellowcake. Yellowcake is converted into gas for enrichment. Then deconversion turns the enriched uranium back into a solid state for fuel pellets. On the back end, nuclear waste disposal and fuel recycling still need advances too, but the immediate boardroom risk is the early chain.

Cameco is already signaling the supply risk. Fortune reports Cameco, the top North American uranium miner based in Canada, is “ringing the alarm bells” that more investment and long-term contracts are needed to ramp up mining rates. As it stands, some of Cameco’s mines are mothballed because no one is willing to pay for the uranium just yet. Isaac also points to conversion bottlenecks: uranium conversion prices have risen from historic lows, yet many refiners remain underutilized. The reason, he said, is that conversion capability was shut in when prices were low, and not all Western conversion capacity is up and running.

Enrichment is its own battlefield, and the U.S. does not have many players. Fortune reports that for enrichment there is only one active enricher in North America: London-based Urenco’s National Enrichment Facility in Eunice, New Mexico. That facility fulfills about one-third of U.S. enrichment demand. Urenco announced in June it plans to expand the site, increasing capacity nearly 50% by 2036. The expansion includes production of a more potent uranium fuel called high-assay low-enriched uranium, or HALEU, required by next-generation reactors with smaller cores. Still, Liebenberg, co-founder and president of LIS Technologies, told Fortune that this is “a small drop in the ocean of what’s needed.” In other words: expansion helps, but it does not erase the scaling gap.

So why are hyperscalers signing reactor contracts while the uranium upstream is lagging? Fortune reports that AI hyperscalers are signing contracts with nuclear developers for next-generation light-water reactors, plus newly developed small modular reactors (SMRs) and microreactors. But they are not yet investing in the uranium mining and refining required for nuclear power. Liebenberg’s point is blunt: “It doesn’t matter what type of reactor; they all need nuclear fuel.” He added that the supply chain issue “trickles down” to mining, and that hyperscalers need to jump in urgently because reactors need fuel “for their own good.” From an executive perspective, that means contracting strategies that focus on reactor output alone may ignore the fuel availability that determines whether those reactors can run.

The Trump effect is part of the story, and it’s also part of the pressure. Fortune notes the federal government has begun investing more in domestic uranium enrichment, but that it must provide much more support and funding to become energy secure. Several enrichment projects are in motion: LIS Technologies is aiming to bring online its LIST Island facility in Tennessee by the end of 2032. Orano is requesting a federal license to build a $5 billion uranium enrichment facility called Project IKE near Oak Ridge, Tennessee, and the company received a Department of Energy award of $900 million this year. Centrus Energy and General Matter also received $900 million each for enrichment plants in Ohio and Kentucky, respectively. U.S. Energy Secretary Chris Wright said in a statement that President Trump is catalyzing a resurgence to strengthen American security and prosperity.

But even with these awards, the most sensitive issue is still timing, not just funding. Fortune reports that if the U.S. were to quadruple its nuclear power, current U.S. uranium enrichment capacity would only fulfill 7% of the total demand. That is the kind of number that should change how boards underwrite schedules and counterparties. It implies fuel access is not a background risk. It is a primary operational input.

Finally, there is an attempt to address fuel supply through the policy lever of weapons-grade plutonium. Fortune reports the Trump administration is pushing to make old, surplus weapons-grade plutonium available as reactor fuel, despite environmentalists and nuclear energy critics decrying environmental and national security risks. The plutonium is more radioactive and hazardous than mined uranium, and it is not naturally occurring, designed for weaponry. Still, selected companies such as SHINE Technologies argue there are benefits. Whether that accelerates fuel availability or adds regulatory complexity, it underscores the same reality: the industry is trying to expand fuel options while the clock moves toward 2028 and the next wave of reactors reaching criticality.

For executives tracking the “second nuclear age,” the strategic stake is clear. The race to criticality is not the same race as the race to supply. If fuel mining, conversion, enrichment, and contracting do not scale together, reactor milestones can become stranded assets, and power plans can turn into price volatility. The winners will be the teams that treat the uranium supply chain as core infrastructure, not as a background assumption.