The first grid-scale sodium-ion system launched in the USA
In July 2025, Peak Energy announced the launch of the first sodium-ion battery system (NFPP) in the United States — and the largest in the world — designed for grid-scale applications. The installation, with a capacity of over 3 MWh, was built at the SolarTAC facility in Aurora, Colorado, and already signals a future free from the dominance of lithium-ion batteries in stationary applications.
New chemistry, new possibilities
The system is based on sodium-ion chemistry using sodium phosphate and sodium pyrophosphate, which, thanks to their exceptional thermal stability, offer an attractive alternative to the widely used lithium iron phosphate (LFP) batteries. According to Cameron Dales, President and Chief Commercial Officer of Peak Energy, the use of sodium allows for better cycle life and calendar life in high-temperature conditions. Combined with a physics-based approach to battery construction, the new technology lays the groundwork for a safer, cheaper, and more sustainable energy storage infrastructure.
Passive cooling
The most innovative feature of the Peak Energy system is its patented passive cooling architecture — operating without fans, pumps, or HVAC systems — that enables effective thermal management of battery modules. This design eliminates 89% of the causes of fires in energy storage systems, which, according to Electric Power Research Institute data, stem from failures in active thermal management.
The benefits are significant:
reduction of auxiliary energy consumption by over 90%,
20% lower operating costs over the entire lifecycle,
33% less cell degradation over 20 years,
up to USD 75/kWh savings in net present value,
lower risk of failure and almost no maintenance requirements.
According to Paul Durkee, Vice President of Engineering at Peak Energy, this is “the lowest-cost grid-scale energy storage system deployed anywhere in the world.”
Joint pilot project
Instead of the traditional approach of testing with a single customer, Peak Energy launched a pilot program with nine partners — utility companies and independent power producers. This strategic move not only accelerates deployment but also reduces costs and technological risk. A key condition for participation in the pilot is the partners’ readiness for commercial deployment if the system meets their expectations. Discussions are already underway for contracts covering nearly 1 GWh of additional installations, scheduled for 2026–2027.
Sodium instead of lithium
Although lithium has become synonymous with modern batteries, its availability and cost are increasingly under scrutiny. Peak Energy points out that sodium — sourced in part from widely available U.S. supplies of soda ash — is cheaper and easier to obtain locally. Moreover, the entire supply chain for sodium-ion cell production can be located within the U.S. or allied countries, enhancing energy security.
The introduction of the One Big Beautiful Bill Act serves as a legislative boost for domestic cell production, rewarding technologies independent of so-called foreign entities of concern and offering tax incentives for projects carried out in the U.S.
Source: Electrec.com