US-based Aalo Atomics has announced the Aalo Pod – a 50 MWe extra modular reactor (XMR), purpose-built to provide scalable on-site power for modern data centres
Aalo said data centres face intense pressures: rapid growth, stringent reliability requirements, siting challenges, and aggressive sustainability goals. Typical power solutions present numerous drawbacks. These include grid limitations; intermittent supply and extensive land use of solar and wind; geographical constraints of geothermal and hydro; and the “dirty nature” of fossil fuels.
Nuclear power presents several advantages aligning with data centre needs but “faces several hurdles. Large NPPs provide reliable, carbon-free baseload power, yet their scale, time to power, and complexity are problematic. SMRs and microreactors offer promising technology but sub-optimal designs for data centres. “The ideal data centre solution requires better power density, siting, scaling, and speed,” Aalo noted.
“We believe that for today’s massive data centre market demand, another category is needed that blends the benefit of the factory manufacturing of microreactors, the power levels of SMRs, and the economic targets of a large reactor. We call it the XMR. The ‘X’ is used because this reactor category is extremely flexible and extra modular.”
Aalo says the XMR is:
- Extra modular (both the reactor and the plant)
- Designed for data centre and mainstream markets
- Expandable – deployable at a wide range of scales with “pay as you grow” scalability
- Extensible – behind the meter (on-site, distributed generation) and in front of the meter (utility deployments)
- Expedient – able to be sited almost anywhere with on-site construction through factory manufacturing, easy field assembly, and a streamlined regulatory path.
- With a simple and robust supply chain for common, available materials, and fuel
- Inexpensive
The Aalo Pod is built around 50 MW modular blocks, easily scalable up to gigawatt levels with a compact footprint – 100 MW on less than five acres. It is designed for 98% reliability and can be reconfigured to achieve 99.9% by a single pod and 99.999% with multiple pods. Each standard Pod comprises five Aalo-1 reactors paired with a single power-generating turbine. An N+1 redundancy configuration can maintain continuous power output even during maintenance or refuelling periods.
Flexible Siting: The Aalo Pod is designed to offer Data Center customers a tremendous amount of flexibility in siting with a relatively small footprint and EPZ (emergency planning zone), a safe, secure, and ruggedized architecture, compatibility with existing grid, generation/storage, and other electrical equipment (e.g. transformers, switch gear, etc.) already in use at the site, and no need for nearby water sources (e.g. rivers, streams).
Aalo expects to deliver power generation solutions from an Aalo Pod within 12 months from order placement and a few months for each additional pod. The Pods support fully independent, grid-parallel, or hybrid operations providing significant flexibility for data centres facing local utility constraints or aiming for complete autonomy.
In December 2024, Aalo received approval from the US Department of Energy-Idaho Operations Office (DOE-ID) to pursue authorisation for the Aalo-X experimental reactor to be located at Idaho National Laboratory (INL). This experimental reactor is intended to pave the way for future commercial applications of the Aalo-1 reactor and help to refine and validate the technology. In May 2024, Aalo said it had completed the conceptual design of the Aalo-1 – a factory-fabricated 10 MW sodium-cooled microreactor that uses uranium zirconium hydride (UZrH) fuel. However, there is very little on the Aalo website about the reactor technology.
