Small modular reactors, once considered a failed experiment in nuclear energy, are experiencing a dramatic comeback as AI data centers desperately search for reliable, carbon-free power sources. Two major reactor development companies have just secured rights to deploy advanced small reactors across the United States, signaling a fundamental shift in how the nuclear industry plans to meet the surging electricity demands of artificial intelligence infrastructure.

Why Are Data Centers Suddenly Interested in Nuclear Power?

The resurgence centers on a simple problem: AI data centers consume enormous amounts of electricity, and traditional power grids are struggling to keep pace. Companies like Microsoft, Google, and OpenAI need reliable, 24/7 power sources that don't depend on weather or time of day. Nuclear energy offers exactly that, but large reactors take decades to build and cost billions of dollars. Small modular reactors, or SMRs, promise a faster, more flexible alternative that can be factory-built and deployed closer to where the power is actually needed.

The timing is critical. President Trump's May 2025 executive order accelerated the Department of Energy's Reactor Pilot Program, instructing the DOE to authorize at least three test reactors and bring them to criticality by July 4, 2026. That deadline is driving real progress. Valar Atomics' Ward 250 reactor achieved zero-power criticality in June 2026, just nine months after groundbreaking on an empty Utah site, making it the second company to reach this milestone under the program.

What Happened to mPower, and Why Is It Coming Back?

BWXT's mPower reactor is a case study in how nuclear projects can fail and be resurrected. The company originally developed mPower starting in 2009 as a Generation III+ integral pressurized water reactor designed to produce 195 megawatts of electricity per module. The design was innovative: the core, steam generator, pressurizer, and primary coolant pumps all fit inside a single vessel roughly the size of a conventional steam generator, allowing for factory fabrication and rail shipment to deployment sites.

In 2010, Babcock & Wilcox and Bechtel formed Generation mPower LLC to advance the design and licensing. The project even secured the first DOE Small Modular Reactor Licensing Technical Support award in late 2012, beating out competing designs from Westinghouse, Holtec, and NuScale. But progress stalled. By 2014, low natural gas prices, cautious utility spending, and the absence of firm customer orders made continued development difficult. Bechtel terminated the partnership in March 2017, and the program was archived.

Now, mPower is getting a second chance. In June 2026, Core Power announced a feasibility study to assess mPower for integration into floating nuclear power plants that could be positioned near demand centers. The same day, Applied Atomics secured an exclusive land-based license to deploy mPower across terrestrial applications.

How Are Companies Planning to Deploy These Reactors?

The new business model differs from the original mPower approach. Instead of utilities building and operating reactors themselves, technology-agnostic reactor developers like Applied Atomics, Core Power, and Elementl Power act as intermediaries. These companies coordinate with reactor vendors to build the reactor design, then partner with offtakers, such as industrial facilities, hyperscalers, or utilities, to operate the reactor and deliver power. The reactor vendors sell the blueprints and license fees, while the development companies take on construction and operational risk.

This model is already moving forward. Elementl Power announced it is developing a nuclear plant of up to 1.5 gigawatts in southeast Ohio using GE Vernova Hitachi's BWRX-300 reactor. Meanwhile, other advanced reactor companies are progressing rapidly through the DOE's streamlined authorization pathway.

Steps to Understanding the Advanced Reactor Deployment Timeline

• Criticality Milestones: Valar Atomics achieved zero-power criticality in June 2026, and Deployable Energy is targeting criticality by July 4, 2026, with Aalo Atomics also positioned to reach this milestone very soon under the DOE Reactor Pilot Program.
• Design Validation: Advanced reactors like the Ward 250 and Unity Nuclear Battery use helium cooling, passive safety features, and low-enriched uranium fuel to demonstrate that smaller, simpler designs can be built faster than traditional large reactors.
• Commercial Deployment: Companies like Core Power and Applied Atomics are moving from test reactors to commercial deployment plans, with mPower reactors targeted for both floating and land-based applications to serve data centers and industrial customers.
• Regulatory Acceleration: The DOE's streamlined authorization pathway is producing results, with private developers advancing from site work to controlled fission in roughly nine months, compared to the decades required under traditional regulatory routes.

The safety features of these new designs are substantial. The Ward 250 and similar reactors include below-grade containment for protection against external events, passive decay heat removal through natural circulation, and gravity-drained water inventories capable of sustaining cooling for extended periods without external power. These passive systems mean the reactors can cool themselves even if all active systems fail, a critical advantage for remote or data center deployments.

Deployable Energy's Unity Nuclear Battery, for example, is a compact, factory-built, helium-cooled microreactor designed to deliver roughly 1 megawatt of electricity. It uses standard low-enriched uranium dioxide fuel at approximately 5 percent enrichment, rather than the higher-enriched fuel that raises proliferation concerns. The company received approval of its Documented Safety Analysis from the DOE's Idaho Operations Office, clearing the way for final commissioning and operations authorization.

The convergence of AI data center demand, streamlined nuclear regulation, and proven advanced reactor designs is creating a moment the nuclear industry has been waiting for. After decades of false starts and canceled projects, small modular reactors are finally finding customers willing to deploy them at scale. For data center operators desperate for clean, reliable power, nuclear energy is no longer a distant possibility, but an imminent reality.