Critical breakthrough for U.S. micro-nuclear reactors: Four have achieved criticality—but how far are they from actual power generation?

July 4 marked U.S. Independence Day—and for the nuclear industry, the date carried added significance. Last year, the Trump administration set a goal: to achieve criticality in three new microreactors by the nation’s 250th anniversary. Today, four reactors have successfully reached criticality—surpassing the original target. Criticality refers to the state where a reactor sustains a continuous nuclear chain reaction—a pivotal technical milestone in nuclear reactor operation. Against the backdrop of surging global electricity demand and intensifying international efforts to secure zero-emission energy sources to combat climate change, this news is easily interpreted as a signal of emerging nuclear technology’s rise. Yet criticality remains far from grid-connected power generation—even falling short of demonstrating practical operational capability. To move from laboratory validation to commercial electricity production, these companies still face a series of formidable technical and regulatory hurdles. This progress stems from the U.S. Department of Energy’s Reactor Pilot Program—a fast-track pathway specifically designed for prototype advanced nuclear reactors. In August last year, the DOE selected 11 microreactor development proposals from numerous applicants, providing them with land access and integrating them into the national laboratory system for technical support. Compared with the large light-water reactors that dominate today’s U.S. power grid, these microreactors are dozens to hundreds of times smaller in scale. Antares Nuclear led the way: its Mark-0 test reactor achieved criticality in June this year. Shortly thereafter, reactors developed by Valar Atomics, Deployable Energy, and Aalo Atomics followed suit. Aalo’s reactor was the final one to cross the finish line—its test completed in the early hours of July 4, nearly hitting the deadline. Such speed is exceptionally rare in nuclear industry history. The most famous counterpoint is Units 3 and 4 of the Vogtle nuclear plant in Georgia: originally projected to cost $14 billion and enter service in 2016 and 2017 respectively, they ultimately connected to the grid seven years behind schedule, with total costs ballooning to approximately $35 billion—more than double the initial budget. By contrast, Valar Atomics, Antares Nuclear, and Aalo Atomics were all founded in 2023; Deployable Energy was established even later, in 2025. Within just one or two years, these startups have reached a technical milestone that traditionally takes over a decade for large-scale projects. Yet behind this speed lies an easily overlooked fact: criticality does not equal power generation. The criticality achieved by these reactors is “zero-power criticality.” Such tests are conducted at extremely low power levels—the core releases negligible energy—primarily to verify whether the nuclear chain reaction can be safely initiated, sustained, and shut down—not to generate usable electricity.

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Based on Blue Energy’s official announcement, the proceeds from this funding round will be allocated across three areas: procurement of long-lead equipment, advancement of project development, and day-to-day operations—with the first being the most urgent. Nuclear power plants rely on several critical components—including large forgings, specialized pumps and valves, and pressure vessels—that typically require three to five years from order placement to delivery. Without securing these contracts early, all subsequent construction timelines would stall. Signing procurement agreements for these items is therefore the essential prerequisite for establishing a realistic, executable project schedule. The first project site has already been confirmed: Victoria Port in Texas. This location satisfies multiple key criteria—it lies near existing transmission lines and fiber-optic networks, boasts abundant natural gas pipeline infrastructure, and supports waterborne transport of oversized equipment. Blue Energy has already signed a cooperation agreement with AI infrastructure firm Crusoe, planning to build a 1.5-gigawatt nuclear-powered data center campus there. According to the timeline, construction could begin as early as Q3 2026, initially relying on natural gas generation before switching to nuclear power once the reactor is complete. The entire cycle—from groundbreaking to nuclear grid connection—is targeted to be completed within 48 months: a fraction of the duration typical for conventional nuclear projects. Achieving this timeline hinges on a construction logic fundamentally different from traditional nuclear development. In interviews with media, Jake explained that his epiphany came from observing how liquefied natural gas (LNG) export terminals are built. A friend working at Venture Global—an American LNG exporter renowned for cutting construction time in half—described their approach. After hearing it, Jake said he “immediately understood.” Though LNG terminals and nuclear plants differ vastly in technology, their underlying construction logic is directly transferable. Blue Energy’s specific strategy divides the nuclear plant into two parts: the nuclear island and the non-nuclear island. The non-nuclear portion—which includes turbines, power generation systems, and cooling auxiliary systems, accounting for roughly 90% of total construction cost—is entirely prefabricated on assembly lines in shipyards, then transported via waterways to the site for installation. For the nuclear island, Blue Energy adopts a key structural innovation: housing the reactor inside a large monopile foundation—a mature solution widely used in offshore wind farms, featuring highly automated production lines, low manufacturing costs, and stable quality control. Placing the reactor within a water body also delivers an added safety benefit: regardless of power loss or extreme events, ample cooling water remains continuously available, significantly enhancing passive safety. A pivotal milestone enabling this approach was already achieved in early 2026: the U.S. Nuclear Regulatory Commission approved Blue Energy’s topical report on licensing, endorsing the company’s phased construction strategy—allowing non-nuclear components to be built first while licensing reviews and construction of the nuclear portion proceed in parallel.

Blue Energy Submits NRC Application for Texas Nuclear Project

5 days ago

Blue Energy Global has submitted an NRC application for small modular reactors at a Texas facility to power a Crusoe data center, partnering with GE Vernova for turbines and reactor designs.

bloomberg

2026-09-16

Blue Energy Submits NRC Application for Texas Nuclear Project

Blue Energy Submits NRC Application for Texas Nuclear Project

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