Company unveils its first extra-modular reactor, designed to deliver zero-carbon energy
As artificial intelligence drives an unprecedented boom in global data center demand, a new generation of nuclear innovators is racing to meet the energy challenge. Among them, Aalo Atomics, a startup based in Austin, Texas, has announced a breakthrough that could redefine how modern data centers are powered and cooled.
In August, Aalo broke ground on Aalo-X, its first nuclear power plant, located beside the Idaho National Laboratory (INL). The project is the first new sodium-cooled test reactor to reach construction in more than four decades, with potential to power data centers in different environments without requiring water for cooling.
According to the company, Aalo-X is the prototype for a scalable line of “extra-modular reactors” (XMRs) designed specifically for power-hungry AI infrastructure. The reactor’s development represents a major leap forward in both nuclear engineering and the sustainability of digital growth.
Traditional nuclear technologies are typically divided into microreactors (less than 10 megawatts electric, or MWe) and small modular reactors (up to roughly 300 MWe). Aalo’s new category, the extra-modular reactor (XMR), bridges the gap between the two. Each Aalo “Pod” combines five 10 MWe Aalo-1 reactors arranged around a single turbine to form a 50 MWe power unit.
The modular format allows operators to scale capacity simply by adding pods, much like stacking server racks in a data center. The key to the system’s efficiency lies in its liquid-sodium coolant, which transfers heat far faster than water. This enables the Aalo-1 reactor to produce up to ten times more energy per unit size than conventional water-cooled designs, while completely eliminating the need for external cooling water systems.
For the data center industry, where cooling demands often consume as much power as computing itself, that design change could be transformative. It allows nuclear power to be co-located directly with data centers, even in arid or water-scarce regions where traditional reactors would be impractical.
Aalo-X is part of a federal initiative to reignite nuclear innovation in the United States. The company has already completed its Conceptual Design Review, secured a site allocation from Department of Energy Idaho Operations Office (DOE-Idaho), and opened a 40,000-square-foot pilot factory in Austin to manufacture reactor modules.
Written by João Fernando
