From ESS News
Juniper Energy will deploy 500 MWh of sodium-ion battery energy storage systems (BESS) – mostly in California – as part of a new strategic partnership with Alsym Energy.
The deal will see Juniper integrate Alsym’s Na-Series technology and is expected to involve deploying sodium-ion battery storage in the Mojave Desert.
High-temperature regions such as the Mojave Desert put higher cooling demands on energy storage assets and both partners of the deal view sodium-ion as a better technical fit than lithium-ion BESS.
US-based Alsym Energy argued the sodium-ion chemistry used in its Na-Series is designed to avoid thermal runaway and can operate efficiently using passive, rather than active cooling. This is expected to simplify balance of plant requirements and therefore reduce upfront capital cost.
Massachusetts-based Alsym Energy officially introduced its Na-Series in October 2025, describing it as non-flammable and non-toxic. The products use materials not sourced from foreign entities of concern (FEOC), which should prevent exposure to customs-related friction.
Mukesh Chatter, CEO and co-founder of Alsym Energy described Juniper Energy as a “forward-thinking” developer that “recognizes the inherent limitations of lithium [battery technology] in warmer environments.”
“Our Na-Series technology was built for exactly this: providing high-performance, fast-charging storage that doesn’t require complex cooling or risk community safety. By manufacturing here in the US, we are ensuring that partners like Juniper can deploy projects faster and more profitably.”
Keith McDaniels, founder and managing partner of Juniper Energy, said the company views sodium-ion technology as the “premier solution” for California’s grid. Alsym’s position as a US-based company should also allow Juniper to take advantage of clean energy tax credits in relation to the projects.
“Alsym’s ability to provide a safe, US-produced battery allows us to maximize tax credits and improve project IRRs while providing our off-takers with a more flexible, reliable, and cost-effective storage asset.”
The deal with Juniper quickly follows the announcement of an 8.5 GWh partnership between Alsym and ESS Tech, Inc. Previously focused on iron flow battery technology, ESS has signed a letter of intent with Alsym to add 8.5 GWh of sodium-ion cells and modules to its portfolio.
It comes as ESS repositions following some financially challenging years for the business. The company reported a significant decrease in revenue in 2025 and a $63.4 million net loss for the year ended Dec. 31, 2025, improving on the $86.2 million net loss in 2024. In February, ESS Tech acquired the intellectual property and assets of German iron flow battery business VoltStorage, strengthening the intellectual property base of the business while gaining access to skilled personnel.
This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.
By submitting this form you agree to pv magazine using your data for the purposes of publishing your comment.
Your personal data will only be disclosed or otherwise transmitted to third parties for the purposes of spam filtering or if this is necessary for technical maintenance of the website. Any other transfer to third parties will not take place unless this is justified on the basis of applicable data protection regulations or if pv magazine is legally obliged to do so.
You may revoke this consent at any time with effect for the future, in which case your personal data will be deleted immediately. Otherwise, your data will be deleted if pv magazine has processed your request or the purpose of data storage is fulfilled.
Further information on data privacy can be found in our Data Protection Policy.