Ameresco to Build 390 MW Molten Salt Reactor for Maryland Army Base
Ameresco and Terrestrial Energy will deploy a 390 MW Generation IV nuclear plant at Aberdeen Proving Ground using low-enriched uranium.
Key points
- Ameresco will install a 390 MW molten salt reactor at Aberdeen Proving Ground to boost energy resilience.
- The plant uses standard-assay low-enriched uranium with less than 5% U-235 to utilize existing supply chains.
- Terrestrial Energy plans to bring first IMSR plants online at US sites in the early 2030s.
Ameresco has secured a contract to install a 390-megawatt Generation IV nuclear reactor at the US Army’s Aberdeen Proving Ground in Maryland. The facility will utilize Terrestrial Energy’s Integral Molten Salt Reactor technology to provide firm, weather-independent power to the site and the regional grid.
The project combines nuclear generation with natural gas to enhance energy resilience at the base, which has operated since 1917. This deployment follows a competitive selection process and builds on a partnership announced in June 2025 to identify similar sites across the United States.
Reactor Design and Operational Output
The IMSR plant is engineered to produce 390 MWe of electricity while maintaining high-temperature, low-pressure operation. Its modular architecture is designed to accelerate construction timelines and adapt output levels to meet the demands of energy-intensive industrial facilities.
According to Interesting Engineering, the system provides firm power, ensuring a stable supply regardless of external conditions. The technology is classified as Generation IV, focusing on inherent safety and the ability to generate high-temperature industrial heat alongside electrical energy.
Fuel Supply Chain Integration
The reactor will be fueled by standard-assay low-enriched uranium, containing less than five percent uranium-235. This specification allows the facility to leverage existing nuclear fuel supply chains, avoiding the need for the higher-enriched fuel required by some other advanced reactor designs.
Deployment Timeline and Phasing
The project will be developed in phases, initially integrating natural gas generation before full nuclear operation. Terrestrial Energy aims to bring its first IMSR plants online at multiple US locations in the early 2030s, with the Maryland base serving as a key initial deployment.
