In the U.S. race to build enough clean, reliable electricity, small modular reactors (SMRs) are increasingly claiming that role.

The technology remains largely unproven commercially, and significant hurdles remain.

Yet a combination of rising power demand, supportive policy, regulatory reform and growing investor interest has transformed SMRs from a speculative concept into what may be nuclear power's strongest growth opportunity.

POWER PINCH

Rising ​demand for electricity from artificial intelligence data centers, industrial reshoring, electrification and new manufacturing investments has spurred the shift in sentiment toward SMRs.

The U.S. Department of Energy has explicitly pointed to growing electricity demand as ‌a key reason for accelerating nuclear deployment.

That is creating new opportunities for technologies capable of delivering around-the-clock power without carbon emissions.

Wind and solar generation continue to expand rapidly, but policymakers, utilities and major industrial customers are increasingly searching for reliable power sources that are not dependent on weather conditions.

WHY MODULAR MATTERS MORE THAN SMALL

The name "small modular reactor" can be misleading.

The real attraction is not that the reactors are small. In fact, smaller reactors sacrifice some of the economies of scale that have historically favored large nuclear plants.

The promise lies in the word "modular."

Traditional nuclear plants are among the most complex ​construction projects in the world. They are built largely on site, require thousands of workers and routinely face years-long delays that sharply drive up costs.

Much of the industry's troubled financial history stems not from poor reactor performance, but ​from difficult construction experiences. SMRs aim to change that model.

Rather than building massive facilities from scratch, developers hope to manufacture major reactor components in factories, ship them to a site and ⁠assemble them using standardized designs.

If successful, that approach could reduce construction risk, shorten timelines and eventually lower costs.

The vision is straightforward: turn nuclear power from a construction business into a manufacturing business.

POWERFUL BACKING

The political environment has become far more favorable as well.

The ​bipartisan ADVANCE Act, signed into law in 2024, directs the Nuclear Regulatory Commission (NRC) to streamline licensing reviews, lower certain regulatory costs for advanced reactor applicants and create more efficient pathways for deployment.

It also encourages development at former fossil-fuel sites and supports regulatory ​approaches tailored to advanced reactor technologies.

That may sound like regulatory housekeeping. For investors, however, predictability is often as important as innovation.

A reactor that faces years of uncertain reviews is difficult to finance. A reactor operating within a clearer regulatory framework is much easier to back.

The federal government is also trying to solve another critical bottleneck: fuel.

Many advanced reactor designs rely on high-assay low-enriched uranium, or HALEU. Until recently, the United States lacked a meaningful domestic supply chain for the fuel.

Through various initiatives, the Department of Energy is working to establish the enrichment and fuel infrastructure needed to support ​commercial deployment.

The Department of Energy is also supporting the development of gas-cooled and sodium-cooled reactors, as well as molten salt and so-called microreactors, in an effort to spur advances across the reactor spectrum.

In other words, Washington is no longer simply supporting reactor ​developers. It is trying to build the broader ecosystem they need to succeed.

REGULATORY REACH

Advanced reactor companies have long complained that they were trying to fit 21st-century technologies into a 20th-century regulatory framework.

Many proposed reactors use different fuels, coolants and operating concepts than the conventional light-water reactors ‌that dominate the ⁠current fleet. Licensing them often required navigating a maze of exemptions and special reviews.

The NRC's new Part 53 framework is designed to create a more technology-inclusive and risk-informed licensing pathway. Rather than forcing every design through the same process, regulators are attempting to accommodate a wider range of reactor technologies while preserving safety standards.

The changes may sound technical, but they address one of the industry's central problems.

A scalable industry requires scalable regulation.

MOVING INTO BUILD PHASE

Optimism has also grown because advanced reactors are finally moving beyond concept studies and investor presentations.

TerraPower's Natrium project in Wyoming has advanced through major permitting and construction milestones, providing one of the clearest examples of an advanced reactor progressing toward commercial deployment.

The project is being developed near a retiring coal power plant, illustrating how advanced nuclear ​could potentially replace aging fossil-fuel generation while reusing existing grid ​infrastructure and workforce expertise.

For an industry that has often ⁠seemed trapped in the future tense, tangible progress matters.

Investors tend to place more confidence in construction sites than in PowerPoint promises.

TOUGH TESTS AHEAD

None of this guarantees success.

SMRs still face formidable challenges. Supply chains must be built. Manufacturing capacity must expand. Utilities must commit to first-of-a-kind projects. And developers must prove that costs fall as deployment grows.

Indeed, the industry's biggest challenge today is no longer ​primarily scientific. It is industrial.

Can reactor modules be manufactured at scale? Can projects be replicated instead of reinvented? Can costs come down through repetition in the same way they have ​in industries ranging from aerospace to ⁠automotive manufacturing?

Most importantly, can a reactor become a product rather than a project?

The history of technological progress offers a simple lesson.

Innovations rarely transform economies when they are invented. They transform economies when somebody figures out how to manufacture them repeatedly, cheaply and at scale.

That may be the point the SMR industry is now approaching.

The future of advanced nuclear no longer hinges mainly on proving that new reactor concepts work. Increasingly, it hinges on proving that they can be built predictably, financed affordably and deployed over and over again.

That is what ⁠makes SMRs nuclear's best ​bet.

Their promise no longer rests primarily on a breakthrough in reactor design.

It rests on a more practical, but potentially more consequential, breakthrough: teaching the nuclear ​industry how to build reactors the way successful industries build products.

The little reactors that could, in other words, may ultimately succeed not because they reinvented nuclear physics.

But because they reinvented nuclear construction.

The opinions expressed here are those of the author, a columnist for Reuters.

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