Since Otto Hahn and Fritz Strassmann achieved nuclear fission in 1938, nuclear energy has gone through cycles of promise, concern, and reinvention.

Early optimism, reflected in US President Eisenhower’s Atoms for Peace speech, gave way to Cold War fears, and later to stagnation following high-profile Chernobyl, Three Mile Island, and Fukushima incidents. The 2000s marked a low point as countries moved to phase out nuclear, and US “renaissance” efforts faltered.

However, today we are at the precipice of a new nuclear age, driven not so much by individual governments as by the insatiable energy needs of data centers. Hyperscalers have been quick to snap up all available power from large-scale reactors, leaving many in the sector looking to a smaller solution to meet their nuclear ambitions. What began as Eisenhower’s vision of “atoms for peace” has evolved into a 21st-century race for “atoms for data,” as the energy needs of AI reshape nuclear’s role in the world.

A small modular solution

For data center developers grappling with unprecedented energy demand from artificial intelligence (AI) data centers, which the International Energy Agency projects will double to 945TWh by 2030, Small Modular Reactors (SMRs) are an attractive concept.

Described by Dr. Tim Gregory, nuclear scientist and author of Going Nuclear, as the “flat pack furniture of the nuclear world,” SMRs are miniaturized nuclear fission reactors, with capacities ranging from 1MW to more than 450MW. At present, more than 127 SMR designs worldwide are at various stages of development, offering a range of capacities and reactor types.

Designs differ substantially, with the central split between Generation III reactors, based on miniaturized versions of current light-water reactor (LWR) designs, and Generation IV, which encompasses next-generation reactor concepts cooled using sodium, lead, molten salt, or gas.

Gen III designs benefit from proven reactor design and a robust fuel and component supply chain. In contrast, Gen IV designs employ advanced fuels and coolants, which can offer higher inherent safety features, greater thermal efficiency potential, and multi-purpose applications. Gen III reactors, adapted from light water reactor designs, cannot scale down to the smallest sizes seen in some Gen IV concepts. Most Gen III designs are at the higher end of the SMR power range, up to 470MW.

In contrast, Gen IV SMRs use entirely novel designs, enabling scalability to very small sizes, even down to 1MW. SMRs are not a new concept. The US first pioneered the technology in the 1950s to power the USS Nautilus, the world’s first nuclear-powered submarine. What is new, Gregory explains, is the private sector’s modular, factory-built approach to the concept, which he says could dramatically cut costs, shorten construction timelines, and reduce political risk by allowing nuclear projects to fit within electoral cycles. In doing so, Gregory says, it could potentially “transform the industry.” For data center developers, this makes SMRs a potential godsend for their power and siting needs, offering a reliable, dispatchable, and flexible energy source, with energy density far exceeding that of other low-carbon alternatives.

For example, SMRs can theoretically deliver about 50 times as much power per square foot as rooftop solar panels. Despite still being years away from commercialization, the promise of SMRs has already led data center operators to flock to sign deals to secure future capacity. Hyperscalers including Google and AWS, as well as colocation providers such as Switch, Endeavour, and Data4, have all penned SMR deals, but no company has been as aggressive as Equinix.

Quiver of energy options

​Equinix is the proverbial cross-bencher of the data center sector, operating both a retail colo-based business and a hyperscale xScale division. Its dual structure has created a uniquely diverse power demand profile, ranging from small single megawatt sites near urban areas to facilities drawing hundreds of megawatts across immense acreage.

​As a result, the company faces a serious challenge: finding an energy source flexible enough to power its portfolio of more than 270 operational sites. The challenge has been exacerbated by prolonged grid-connection timelines across major markets, particularly in the US and Europe, and by demand growth that is now outpacing the power system’s ability to keep up.

​To meet this daunting challenge, Equinix required what its SVP of Global Energy, Adrian Anderson, dubs “a quiver of energy arrows” comprising a range of technologies tailored to each data center site and grid constraint.

​The company has since filled this “quiver” with a mix of energy sources, from renewables to fuel cells. However, with traditional renewables unable to deliver firm baseload power and fuel cells still reliant on natural gas, Equinix has increasingly turned to SMRs as a possible panacea for its long-term energy needs.

​Deal count

​While most data center companies have partnered with a single SMR provider – Google with Kairos Power and AWS with X-energy – Equinix has signed agreements with no fewer than four different companies to date.

​Its first foray into the wide world of SMRs came in April 2024, when it announced a non-binding agreement with US SMR developer Oklo for up to 500MW of future capacity. It followed this up in August with a trio of agreements with Radiant Industries, ULC Energy, and Stellaria, which brought the company’s total commitments to more than a gigawatt of future SMR capacity.

​What made these deals notable is not only the sheer capacity involved but also the diversity of reactor types, reflecting Equinix’s need for varying power options. The agreements spanned more conventional reactor types, such as Rolls-Royce’s 470MW SMR, which utilizes pressurised water reactor (PWR) technology, to Stellaria’s 250MW Gen IV fast-molten-salt reactor (FMSR), and Radiant’s 1MW microreactor design.

​“Microreactors or small SMRs could work well for localized deployments, while larger SMRs could support our hyperscale campuses,” says Anderson. “It’s about matching the right technology to the right context.”

​Another notable aspect of the agreements is their international scope, spanning US and European markets and multiple reactor types, highlighting that deployment strategies and development philosophies differ across regions.

​According to Anderson, Equinix’s agreements were not just power purchases, but efforts to incubate the SMR sector. He argues this responsibility should not rest only with the hyperscalers, and says Equinix aims to show that colocation providers can also foster innovation and help democratize access to advanced, carbon-free power.

Anderson identifies three main levers that he says could have a tangible impact on supporting the technology’s commercialization, namely: “Signaling the market through long-term offtake commitments, enabling financing with PPAs as bankable annuities, and fostering collaboration through targeted investments and partnerships.”

Taking a closer look at each agreement and deployment model of each SMR developer provides insight into how the company expects these technologies to evolve and how they may ultimately power the sector.

​AI Era

Unlike traditional data centers running task-specific software, AI training clusters experience sharp, unpredictable spikes in consumption, necessitating a stable, energy-dense, always-available power source. For Equinix’s xScale division, this is a clear and present need, exacerbated by constrained grids and the inability of intermittent renewables to meet these requirements.

​This need led Equinix to Stellaria, a French SMR startup founded by Technip Energy and Schneider Electric in 2023 to deliver an SMR ideally suited for the AI data center market. Its partnership with Equinix was not only one of the largest deals in the space, representing a 500MW pre-Power Purchase Agreement (PPA), but also one of the first binding deals in a sector where non-binding but headline-capturing MoUs and LOIs have become commonplace. The companies followed this up in November, signing a pre-order agreement, with Equnix securing the first energy capacity reservation from Stellaria’s inaugural commercial reactor.

​So what drew Equinix to Stellaria? According to Stellaria CEO Nicolas Breyton, the relationship emerged through Stellaria’s industrial network, especially its ties with Schneider, Equinix’s primary power systems supplier. That introduction quickly evolved into a collaboration focused on developing a decarbonized, high-density baseload power solution capable of responding to the sharp fluctuations in GPU-driven workloads.

​In response to the challenge, Stellaria designed a 250MW Generation IV FMSR, which Breyton claims is “perfectly suited for xScale AI data centers that demand continuous, high-density power.”

The Stellarium reactor not only matches the power scale and continuity needed by modern AI campuses but also addresses another challenge, namely that low-carbon power sources often lack grid-stabilizing inertia. Most conventional power sources provide inertia via spinning turbines that slow down the rate of frequency change during a sudden supply or demand imbalance. Breyton claims Stellaria’s SMR can provide a “shock absorber” through the reactor’s thermal inertia.

​“AI data centers don’t consume power like classic ones,” he says. “GPUs surge and fall — they need inertia, flexibility, and stability. That’s exactly what molten salt reactors can provide.”

Stellaria and Equinix are evaluating several deployment models, including behind-the-meter installations and utility-operated configurations. Each site is expected to use SMRs in redundant pairs, backed by gas turbines and grid interconnection, to achieve full N+1 availability. In this setup, Breyton argues that data centers can become power producers, as well as consumers, with the ability to inject excess power back into the grid when needed.

“Data centers will not only become a data hub, but also an energy hub thanks to the installation of the SMRs onsite,” contends Breyton.

​This is especially important within the European market, where many grids are reaching a breaking point, stifling data center development. Through placing reliable, abundant nuclear power at the center of industrial campuses, Stellaria aims to enable clusters of data centers and other energy-intensive industries to form self-sufficient energy islands. And it is not the only company to be pursuing this idea.

Energy Islands

​Nowhere in Europe is facing the same level of power constraints as the Netherlands. Once the interconnectivity center of the world, the country’s position as a data center hub is slipping, with its grid stretched to near breaking point.

As a result, grid fees in the country have risen by up to 95x for large baseload users, with large-scale data centers unable to secure firm grid connections. For ULC Energy, nuclear project developer and exclusive Dutch vendor for Rolls-Royce SMR, powering the data center sector in the Netherlands is increasingly taking a behind-the-meter flavor.

“When you look at the grids in the European mainland, the Dutch grid is probably closest to getting really constrained,” ULC CEO Dirk Rabelink says. “We have a relatively small country, a very high dependency on natural gas, and our electricity system is undersized versus the energy activity that we have.”

Consequently, ULC is aiming to deploy its SMRs as part of “energy islands” that can serve as self-contained clean-power hubs, delivering dedicated electricity to a range of offtakers. Underwriting such a large project required an anchor offtaker willing to take up the bulk of the energy through a long-term supply agreement. This is where Equinix stepped into the fold, agreeing to a (non-binding) PPA for 250MW of capacity. The agreement has benefits for both parties, giving ULC a large, creditworthy offtaker to improve plant economics and attract investment, and Equinix future baseload power for one of its facilities.

Underpinning these energy islands will be the largest SMR planned for commercial deployment. Developed by Rolls-Royce SMR, the reactor is based on established PWR technology and is expected to exceed 470MWe. For ULC, the choice came down to proven technology.

​“Rolls-Royce’s SMR stood out because it combined proven light-water technology, standard low-enriched uranium fuel, and a vendor with real manufacturing depth,” says Rabenik. “For us, it wasn’t enough to have a clever design – we needed a partner that could actually deliver a full power plant with a clear supply chain and modules sized for practical transport.”

Though the deal with Equinix is likely to see ULC supply power to the company behind-the-meter, the firm ultimately aims to make each energy island a hybrid power node, connected to the grid but capable of operating independently when required. That flexibility is central to its appeal for data centers, Anderson notes. “I really believe hybrid solutions are going to be essential. Staying connected to the grid allows us to sell power into it, draw power from it when needed, and ultimately enhance its reliability and capacity,” he asserts.

Although data centers are considered the ideal anchor offtaker for ULC, the company was careful to ensure it was not the sole offtaker. Instead, ULC hopes to power a range of other industries, such as hydrogen developers, small and medium enterprises, and potentially district heating systems. This is a model endorsed by Equinix, with Anderson contending that the perfect configuration would position “the data center as the SMR’s anchor off-taker, while retaining the ability to deliver power to additional customers, the public grid, and nearby communities.”

Middle Ground

​While Equinix’s deals in the European market have focused on larger SMR companies, its US agreements have reflected a smaller, more modularized approach.

Compared to Rolls-Royce’s 470MW behemoth, Santa Clara-based Oklo’s Powerhouse reactor is relatively small, boasting a capacity of 75MW. However, for the company, which has signed by far the most deals within data center space of any SMR vendor, boasting a customer pipeline exceeding 14GW of mostly non-binding capacity, it is this size that it says makes it best suited to the needs of the data center market.

The modular nature of Oklo’s fast fission reactor is designed specifically to “mirror the way data centers grow hall by hall, in 100MW increments,” said Brian Gitt, the company’s SVP and head of business development. This can enable greater flexibility, Oklo says, allowing reactors to be colocated with major data centers or connected via the grid under a PPA. Operators will have flexibility to match supply with demand and reduce exposure to grid bottlenecks, a significant concern for Equinix.

“Equinix is uniquely positioned because of its massive distributed footprint,” Gitt asserts. “As AI agents begin to interact in real time, latency and performance will define competitiveness, and that means power and compute must move closer to where people live and work.”

Therefore, according to Gitt, the deal with Equinix reflects the company’s practical needs, providing an option that could power both large hyperscale data centers and smaller-scale inference sites.

​On the Edge

But ​what about sites even further out towards the Edge that require a smaller-scale, reliable system to power operations solely behind the meter? While hyperscale deployments get the headlines, there is a growing school of thought within the sector that small-scale data centers supporting inference workloads will come to dominate.

Many of these facilities are planned for urban locales, where grid connection can often take up to ten years, meaning the need for a dispatchable, baseload energy source has never been greater.

Unlike most SMR developers focused on multi-hundred-megawatt designs, Radiant Industries is targeting the opposite end of the spectrum. Its 1.2MWe and 3MWth helium-cooled Kaleidos micro-reactor is small enough to fit in a container and designed to be shipped directly to an end user for rapid installation.

“We’re not competing with large-scale nuclear developers; we’re solving a different problem – bringing power to places where it’s not available, or not available fast enough,” says Mike Starrett, chief revenue officer at Radiant.

A key selling point for the data center sector is the reactor’s potential for quick, easy deployment. As a fully factory-manufactured, containerized solution, Starrett claims it can go from truck-to-power in as little as 24-48 hours, with a more realistic commercial deployment timeline of a few weeks. That timeline is faster even than natural gas, which has become the go-to option for operators seeking quick, dispatchable supply. The company plans to start construction at its first reactor factory in Oak Ridge, Tennessee, in 2026, aiming to scale up production to 50 reactors per year by 2028.

For Equinix’s retail business, which operates more than 200 data centers in and around urban areas, Radiant offered an attractive solution, leading the company to pre-order 20 of its microreactors.

“Microreactors, or micro SMRs, can be highly effective where smaller-scale deployment makes sense – providing bridging capacity or powering compact data centers,” explains Equinix’s Anderson.

Radiant’s deployment model focuses on behind-the-meter energy, meaning the reactors supply power directly to the data center or nearby facilities, rather than relying on constrained public grids. Starrett clarifies that this approach can serve both existing facilities looking to expand capacity and new builds.

The small size could also have significant logistical advantages for Equinix, allowing it to scale its edge data center portfolio more rapidly than with conventional energy sources, offering a completely different approach to the deals Equinix signed in Europe.

Bottlenecks and Barriers

​The promise of SMRs is undeniable. Compact, factory-built, and capable of supplying dispatchable, carbon-free power to data centers and other industries, SMRs could truly transform the energy landscape for the sector. Yet, despite these advantages, commercial deployment remains highly uncertain. Current forecasts point to the 2030s at the earliest, with progress contingent on the development of full supply chains, licensing frameworks, and financing mechanisms.

​One of the most pressing bottlenecks is licensing and regulatory approval. Current US and global processes involve years of site assessment, environmental review, and multi-jurisdictional compliance. For SMRs, these processes could be even longer, with regulators forced to adapt rules originally designed for large reactors to smaller, untested designs. As a result, calls for regulatory reform and direct state backing have intensified to prevent the “new nuclear age” from stalling.

The US Department of Energy (DOE) has responded aggressively to these calls by launching several pilot projects intended to streamline early deployments. The most notable of these is its Reactor Pilot Program, which seeks to establish a DOE-led pathway for advanced reactor demonstration to streamline commercial licensing. In May, the DOE selected 11 developers, including Radiant and Oklo, to build first-of-a-kind test reactors at Idaho National Laboratory (INL).

“We’ve got reactor developers piloting their first reactors at INL, not just experimenting but actually building them to demonstrate viability,” says Brian Smith, head of reactor development at INL. “This shows the investor community that advanced nuclear is real. These reactors will be up and running at INL this decade.”

The pilot aims to support at least three reactors achieving criticality by 2030, providing proof of operational viability for investors and stakeholders. “These are not paper designs. This is real metal being deployed on the ground in Idaho and elsewhere,” Smith insists.

Two companies have already broken ground. Oklo started construction in September, and Aalo Atomics, which is developing a sodium and air-cooled reactor, in August. Radiant has completed its front-end engineering and expects installation and testing to begin in early 2026.

Despite DOE support, full commercial deployment will require approval from the Nuclear Regulatory Commission (NRC), which could require additional years of documentation and review. To date, only NuScale Power has received NRC approval in 2023. Other projects, such as mPower and HoloGen, have faltered due to slow NRC processes and funding challenges. Oklo, too, encountered significant setbacks after its initial license application was rejected for insufficient design information.

Smith, however, stresses cautious optimism. “We have to remain grounded in truth and frankly, remain highly cognizant of where the challenges lie, and then actively work on how to get in front of those and tackle those challenges.”

Regulatory uncertainty is not confined to the US; it is even more pronounced in the European market, where SMR deployments face a patchwork of licensing processes due to the lack of a single EU nuclear authority.

As a result, each European country has its own nuclear regulator, meaning that even if an SMR is approved in one country, it is unlikely to be automatically fast-tracked in another. Divergent national attitudes toward nuclear muddy the waters even further, from restrictive Germany to pro-nuclear France and the Czech Republic, meaning we are likely to see staggered approvals across the continent.

The standardized nature of SMRs could hasten the process. SMRs use repeatable, factory-built designs, allowing regulators to reuse safety cases. In addition, established vendors such as Rolls-Royce SMR, which are building better-understood Gen III designs, could benefit from an expedited regulatory process.​

“We’ve spent significant time with regulators in all our target countries. The feedback we receive is consistent: our reactor is ‘boring’, and in nuclear, boring is the highest compliment,” asserts Harry Keeling, head of Business Development, Rolls-Royce SMR.

However, despite confidence, Anderson remains grounded in his expectations. “The realist in me says I’ll wait and see – positive discussions are one thing, but aligning the various regulators in practice is always far more complicated,” he claims.

​Capital costs

​Even if an SMR secures regulatory approval, another barrier emerges: financing. First-of-a-kind SMRs are projected to cost between €4,000 ($4,606) and €6,000 ($6,909) per kilowatt in Europe, compared to the current average energy cost in Europe, which stands at €0.2872 ($0.33) per kWh (first half of 2025). Therefore, driving down the cost curve for the reactors will be of utmost importance to support their deployment and uptake.

The real challenge for developers is the capital required to move from the prototype to the commercialization stage, where risk is highest and traditional debt is scarce.

“No bank will take on technology risk. Project financing for SMRs requires proven, reliable technology with established off-take agreements to mitigate project cash flow risks,” says Ivan Pavlovic, executive director, energy transition at investment bank Natixis

Stellaria CEO Breyton says this is akin to “crossing the desert.” He estimates his company will require €600 million ($690m) to move from prototype to commercial readiness. Breyton notes that this figure is comparable to “a simple highway connection,” yet far more complex to secure because it falls outside regular political and investment cycles.

To bridge the gap, Breyton argues that large public-sector programs are essential. Stellaria is currently pushing for inclusion in Europe’s IPCEI framework, which unlocks significant state subsidies for strategic technologies. He stresses that nuclear innovation requires “a strong policy that will push the innovation for ten years.” An issue in countries with five-year election cycles, which often stymies governments from making grand long-term investments.

However, to support the sector, governments must step up, not only by co-funding projects but also by underwriting the wider supply chain. “Public-private partnerships are essential to share early-stage costs and risks. In fact, an insurance product to cover cost overruns could make a lot of sense,” argues Equinix’s Anderson.

​At present, most projects are seeking public funding; however, on the private side, data centers are emerging as the sector’s most significant financial backer. ULC’s Rabenik argues that the capital outlay required to support the growth of SMRs is minimal compared to the vast amounts splashed out on multi-gigawatt data centers. “The data center can pretty much afford this from the outset,” he says. “Our analysis actually shows that the investment in the data center outweighs the investment in the nuclear power plant, even before the semiconductor capex is considered.”

Anderson contends that long-term PPAs from data centers are already reshaping the financing landscape for SMRs. “These contracts function almost like an annuity, allowing technology developers to secure debt or bank financing to fund their projects.”

However, the economics of nuclear power mean bigger is better, and SMRs are unlikely to see the benefits of miniaturization experienced by other technologies. Therefore, leveraging modular factory-built design will be key to achieving the cost predictability that investors and operators need.

Radiant’s Starrett likens it to “buying a catalogue of cabinets rather than renovating a bespoke kitchen”. By producing each reactor identically, he says SMRs avoid the overruns that have plagued larger nuclear projects.

As a result, optimists contend that, unlike conventional nuclear, where debt can account for half of the energy cost, taking advantage of SMRs’ modularity could reduce on-site construction risks, streamline operations, and significantly shorten project timelines, making nuclear power much more accessible.

​Fuelling up

Once the reactors are approved, financed, and built, developers will need to find some fuel. Availability and production of fuel are, by all accounts, the biggest bottleneck for SMRs’ successful commercialization.

The reactors will require a whole lot of uranium, but, at present, around three-quarters of global stocks are sourced from three countries: Kazakhstan, Canada, and Australia. At the enrichment stage, the bottleneck tightens even further, with Russia still dominating capacity.

“In the early 1990s, the US was the world’s biggest exporter of nuclear fuel. Then Russia flooded the market with cheap enriched uranium – less than half the price – and our entire industry was wiped out,” says Christo Liebenberg, CTO at Lis Technologies, a firm that is taking a novel approach to uranium enrichment.

Since 2022, the US and EU have instituted a ban on importing enriched uranium from Russia, with a waiver process currently in place. As a result, there is now an inherent requirement for a localized nuclear fuel supply chain to power future SMRs.

To address this bottleneck, the US government has committed about $3.4 billion to uranium production. Several European countries are expanding production too, with France recently announcing a more than 30 percent capacity increase at its Georges Besse 2 uranium enrichment facility.

Smith says the “government can act as the offtaker” in the US market. He explains: “We’ll buy the enriched uranium and ensure it reaches the reactor vendors who need it. Industry just has to build the facilities.”

While efforts to reshore uranium enrichment are making headway, for the vast majority of advanced SMRs, traditional standard low-enriched uranium used in most Gen III designs won’t suffice. Instead, they require HALEU (High-Assay Low-Enriched Uranium), which is commonly 15-20 percent more enriched. This higher energy density allows reactors to be smaller, simpler, and refueled less often, a significant advantage for data center developers, where operations benefit from long fuel cycles and minimal downtime.

But HALEU has one big problem: it hasn’t yet been produced at scale. At present, there is no domestic commercial large-scale supplier in the US, with the DOE supplying limited amounts by downblending its highly enriched stockpile.

As a result, the cost to produce the fuel, even in limited test quantities, has skyrocketed from about $10,000/kg to $30,000/kg in the last five years, blowing apart many SMR business models that relied on cost reductions to ensure their products were affordable.

Another concern is the regulatory and security complexities that mass production of the fuel would entail, since enriched uranium above five percent is more tightly controlled internationally. Consequently, there are concerns that with advanced nuclear development could come clandestine attempts to enrich uranium to weapons-grade levels, potentially consigning fabrication of the fuel to nuclear-powered states.

The final concern is the current lack of clear market demand, which means private fuel cycle companies are hesitant to invest, creating a ‘chicken and egg’ problem that delays the deployment of advanced reactors and SMRs alike.

Despite this, there has been some progress in the supply chain, with companies pioneering laser enrichment technologies promising significant cost reductions. One of these is Lis Technologies, which, instead of relying on massive centrifuge cascades, uses a continuous-wave laser, which it claims is much more efficient than centrifugal methods.

“We can enrich fuel more efficiently, with fewer stages and a smaller footprint than traditional centrifuges,” claims Liebenberg. “That means producing HALEU at a fraction of today’s cost – potentially $10,000 to $14,000 per kilogram instead of $30,000.”

Though this sounds encouraging, SMR developers remain grounded in their outlook. “We don’t promise unrealistic roadmaps,” says Stellaria’s Breyton. “2027 SMRs are a lie – the fuel isn’t ready.”

This has led some to contend that, while fuel constraints are a bottleneck, they are a future problem, not a present one. As Kevin Kong, CEO of Everstar, puts it, fuel scarcity becomes a real issue only once reactors are being produced and deployed at scale. “Fuel is a problem when you have reactors,” he stresses. A milestone that could still be more than ten years away.

​Five years away from being five years away

​Talk to anyone in the SMR sector, and it’s easy to get carried away by the technology’s immense potential. But the persistent question that remains is when, or if, these reactors will become a commercial reality. The bottlenecks have led to divisions across the sector over realistic timelines, with some extremely bullish and others more pragmatic.

At the ambitious end sits Oklo. The company is targeting first power before the end of the decade, based on securing fuel allocation, a permitted site, and having already commenced construction of its test reactor. Unlike most competitors, it positions its first unit as fully commercial rather than a demonstration. Oklo’s aggressive timeline has faced criticism, with a recent Bloomberg report contending that its high valuation has been based on “hype” rather than fundamentals, especially given its initial NRC rejection back in 2022, with a former senior agency official reportedly calling Oklo “probably the worst applicant the NRC has ever had”.

​Radiant, too, has adopted an aggressive deployment timeline, planning to complete its first full-scale deployment in the US by 2026. Following this, it plans to ramp up factory manufacturing and make deliveries to customers with NRC-authorized reactors by early 2028 or late 2027, claims Starrett.

​For others, including the majority of the emerging Generation IV developers, the mid-2030s are seen as the most realistic horizon. Stellaria is among the more open and methodical of this group, laying out a clear roadmap that includes a safety demonstrator by 2030, complete system validation by 2032, and first deployments at data centres and industrial sites in 2035.

​This aligns with the timelines of other Gen IV players such as Kairos, which, under agreements with Google and the Tennessee Valley Authority, also points to first commercial deployments around 2035.

​National strategies reflect this uneven picture. The first Rolls-Royce units are slated for deployment in Wales, with construction expected to start this year. Meaning ULC’s Dutch deployments will likely only begin work around 2035 at the very earliest.

​For Equinix, pragmatism is the name of the game, with Anderson frank about the uncertainties that still surround the sector, accepting that not all reactor concepts will reach commercialization. As a result, Equinix only expects the first successful units from current partnerships to come online in the mid-2030s. The long wait, Anderson suggests, has less to do with the technology itself and more with all the moving parts around it.

​“We want to create as many opportunities for success and collaboration as possible,” he says. “We don’t have a crystal ball, so we need to be pragmatic – not overextend ourselves, but also recognize that some projects will fail. That’s just part of innovation.”

​What seems increasingly clear is that consolidation across the sector is inevitable. With hundreds of designs currently in play, it’s evident that only a handful are likely to emerge as commercially viable once real-world data separates engineering promise from economic reality.

​“In the end, we only need maybe half a dozen successful reactor designs globally. That’s it,” affirms Tim Gregory.

​This has led some in the industry to argue that a slower, steadier pace may ultimately serve SMRs better, as a mad rush to first criticality risks creating bottlenecks. As for a true SMR-powered future to come to fruition, the products themselves will have to be near-perfect to assuage concerns over safety, financial viability, and regulation, which are currently threatening the sector.

​In addition, while the data center market has shown significant backing to the sector, it is unlikely to be the first beneficiary of its power output. The majority of reactors are likely to be operated by a third party – either the utility or the SMR developer itself – meaning a longer time scale and a larger investment than for a data center. As a result, the provider is unlikely to forgo a connection to the grid, to ensure continuous demand, especially given the growing risk of a market correction within the AI space, which could see many planned data center projects not come to market.​

Despite the speculation and bottlenecks, there is room for hope, argues Gregory. “Will SMRs be commercialized? Absolutely yes. The only question is which designs,” he says. The bigger question is how long we will have to wait to see this nuclear-powered future become a reality.