Two major nuclear companies are taking a different approach to powering artificial intelligence: they're building new reactors based on designs that already work, rather than inventing entirely new ones. Westinghouse is expanding its APX technology platform to serve both large reactors and smaller modular units, while Holtec is partnering with utilities and international firms to deploy its SMR-300 reactors across the U.S. Gulf South. This strategy of reusing proven nuclear blueprints could help meet the surging electricity demands of AI data centers faster than developing novel reactor architectures from the ground up.

What's Driving the Shift Toward Proven Nuclear Designs?

The nuclear industry faces a timing problem. AI data centers and other energy-intensive industries need reliable, carbon-free power now, but building new reactor types from scratch takes decades of engineering, testing, and regulatory approval. By leveraging existing reactor technology, companies can compress that timeline significantly. Westinghouse's approach centers on its APX platform, which serves as a common engineering foundation for both its large AP1000 reactor and its smaller AP300 small modular reactor (SMR). The shared platform extends across engineering, major components, fuel design, licensing strategies, and parts of the supply chain, meaning utilities can deploy either reactor type without creating separate industrial ecosystems.

Holtec International is pursuing a similar strategy with its SMR-300 reactor, a 320-megawatt electrical (MWe) Generation III+ small modular reactor that uses pressurized water reactor (PWR) technology. On August 4, Holtec signed a non-binding memorandum of agreement with Louisiana's Entergy Services and South Korea's Hyundai Engineering & Construction to assess potential dual-unit SMR-300 projects in the U.S. Gulf South. A standard dual-unit SMR-300 would generate 680 megawatts (MW) of carbon-free electricity, with each reactor producing about 340 MW of electrical power.

How Are Companies Accelerating Nuclear Deployment for AI?

• Shared Engineering Platforms: Westinghouse's APX technology allows the company to develop both large and small reactors using the same core design principles, reducing the complexity of bringing new reactors to market and simplifying future deployments across different customer types.
• Factory-Built Modular Components: Holtec's SMR-300 uses a modular design where major reactor parts are manufactured in factories before being assembled on site, reducing construction time and costs compared to traditional on-site building methods.
• Proven Safety Systems: Both the AP300 and SMR-300 rely on passive safety systems and established pressurized water reactor technology, meaning regulators and utilities can evaluate them against known performance standards rather than entirely novel designs.
• International Partnerships: Holtec's collaboration with Hyundai Engineering & Construction leverages the South Korean firm's balance-of-plant engineering expertise, while Westinghouse's expanded partnership with engineering firm Amentum provides additional resources for licensing and project execution.
• Reference Plant Strategy: Holtec is using its first SMR-300 projects at the Palisades site in Michigan, called Pioneer 1 and Pioneer 2, as reference plants for future deployments, allowing the company to demonstrate performance and build confidence among other utilities.

The regulatory pathway is also smoother when building on proven designs. Westinghouse's AP1000 already operates commercially, giving the company an established technology base. The AP300 applies many of the same design principles to customers seeking lower generating capacity without moving to an entirely different reactor architecture. Amentum will support the engineering work required during the licensing process for the AP300, an important step before the reactor can enter the commercial market.

Why Does This Matter for AI Infrastructure?

Reliable, around-the-clock electricity has become a growing priority as power demand rises from data centers, artificial intelligence infrastructure, and industrial expansion. Nuclear developers increasingly see both conventional reactors and SMRs as potential options for meeting those long-term energy needs. The collaboration between Westinghouse and Amentum is expected to accelerate NRC (Nuclear Regulatory Commission) licensing for the AP300 while strengthening engineering support for larger reactor projects. This dual focus allows the company to address electricity demand from AI and other energy-intensive industries simultaneously.

"There is an expanding global market for firm baseload power," stated John Heller, CEO of Amentum. He added that the collaboration with Westinghouse will help address electricity demand from AI and other energy-intensive industries.

John Heller, Chief Executive Officer at Amentum

For Holtec, the focus is on identifying commercially viable opportunities where advanced nuclear can support economic growth while strengthening long-term grid reliability and energy security. The Gulf South region, which includes Georgia, Alabama, Mississippi, Louisiana, Florida, and Arkansas, is a strategic target because Entergy operates one of the largest nuclear fleets in the U.S. and supplies electricity across much of the area. The partnership will assess customer demand, potential sites, and commercial models for deploying the dual-unit SMR-300 reactors.

"The objective is to identify commercially viable opportunities where advanced nuclear may be able to support economic growth while strengthening long-term grid reliability and energy security," Holtec International representatives stated.

Holtec International

Holtec emphasized that major reactor parts will be manufactured in the U.S. at its Advanced Manufacturing Division, with plans to expand manufacturing capacity to support future reactor deployments. This domestic manufacturing strategy addresses both supply chain resilience and job creation concerns.

What's the Timeline for These Reactors?

While the memorandum of agreement between Holtec, Entergy, and Hyundai Engineering & Construction does not commit the parties to build any reactors, it represents another step in Holtec's strategy to commercialize its SMR-300 technology through partnerships with utilities. The company is positioning its first SMR-300 projects at Palisades in Michigan as reference plants that will demonstrate performance and build confidence for future deployments. For Westinghouse, the expanded partnership with Amentum is expected to accelerate the licensing process for the AP300, though no specific deployment dates have been announced.

The broader context is one of urgency. As electricity demand accelerates across the United States, both companies are positioning their proven reactor designs as solutions that can be deployed faster than entirely new nuclear architectures. By building on existing technology, engineering expertise, and regulatory pathways, these companies hope to compress the timeline from concept to operation, making nuclear power a viable option for the energy-intensive infrastructure that AI and other industries require.