World’s largest 4.75 GWh sodium battery system set for US grid storage
Last Updated: Nov 2025
US-based Peak Energy, a company focused on developing giga-scale energy storage technology for the grid, has announced a significant, multi-year agreement with Jupiter Power, a prominent developer and operator of utility-scale battery energy storage systems.
Under the terms of the phased agreement, Peak Energy will supply up to 4.75 GWh of its sodium-ion battery energy storage systems (ESS). These systems are slated for deployment across Jupiter Power’s projects between 2027 and 2030.
“Deploying the world’s largest sodium-ion energy storage system with one of the nation’s top Independent Power Producers proves that sodium is ready for today and will dominate the future,” noted Landon Mossburg, CEO and Co-Founder of the energy firm.
The total contract value could exceed $500 million, representing a notable milestone for the sodium-ion storage sector.
The agreement’s initial phase stipulates the delivery of approximately 720 MWh of storage capacity in 2027. This single delivery is set to be the largest announced deployment of sodium-ion batteries to date.
Beyond this, the deal includes a substantial capacity reservation option for Jupiter Power, covering a further 4 GWh of Peak’s systems for the 2028-2030 timeframe.
Fully passive design
Jupiter Power’s selection is based on the specific operational and financial metrics of Peak’s proprietary sodium-ion (NFPP) system, which the company launched shortly before this announcement.
A central feature of the technology is its fully passive design, which eliminates the need for active cooling systems. This design choice results in a significant reduction in auxiliary power use, up to 97 percent, and enables safer operations.
These technical specifications are expected to translate into a more favorable total cost of ownership. The company stated its system offers nearly 30 percent better cell degradation performance over a 20-year operational life compared to many current lithium-ion alternatives.
This lower degradation rate can reduce or eliminate future augmentation requirements, meaning operators may not need to add additional battery units over the project’s lifespan to maintain its original storage capacity.
By eliminating many of the components associated with active cooling—parts that typically require routine maintenance, repair, and replacement—the system is projected to have lower overall operations and maintenance (O&M) costs.
To deliver long-term savings
“From day one, we have believed that sodium-ion will be the winning technology for grid-scale storage, which is absolutely essential to meet increasing demand from hyperscalers and AI,” added Mossburg.
He noted that Jupiter Power “deeply understands the need to invest in and deploy technology solutions that will deliver long-term financial and operational savings.”
Mike Geier, Jupiter Power’s Chief Technology Officer, framed the agreement as part of a broader strategy.
“Jupiter Power is excited to support domestic battery energy storage manufacturing as we continue to increase the deployment of firm, dispatchable energy when and where it’s most needed,” Geier concluded. He described Peak Energy as a “first mover in domestic sodium-ion technology.”
The agreement serves as a validation of Peak’s scalable, drop-in solution and supports its efforts to build US’ domestic sodium-ion supply chain.
US-based Peak Energy, a company focused on developing giga-scale energy storage technology for the grid, has announced a significant, multi-year agreement with Jupiter Power, a prominent developer and operator of utility-scale battery energy storage systems.
Under the terms of the phased agreement, Peak Energy will supply up to 4.75 GWh of its sodium-ion battery energy storage systems (ESS). These systems are slated for deployment across Jupiter Power’s projects between 2027 and 2030.
“Deploying the world’s largest sodium-ion energy storage system with one of the nation’s top Independent Power Producers proves that sodium is ready for today and will dominate the future,” noted Landon Mossburg, CEO and Co-Founder of the energy firm.
The total contract value could exceed $500 million, representing a notable milestone for the sodium-ion storage sector.
The agreement’s initial phase stipulates the delivery of approximately 720 MWh of storage capacity in 2027. This single delivery is set to be the largest announced deployment of sodium-ion batteries to date.
Beyond this, the deal includes a substantial capacity reservation option for Jupiter Power, covering a further 4 GWh of Peak’s systems for the 2028-2030 timeframe.
Fully passive design
Jupiter Power’s selection is based on the specific operational and financial metrics of Peak’s proprietary sodium-ion (NFPP) system, which the company launched shortly before this announcement.
A central feature of the technology is its fully passive design, which eliminates the need for active cooling systems. This design choice results in a significant reduction in auxiliary power use, up to 97 percent, and enables safer operations.
These technical specifications are expected to translate into a more favorable total cost of ownership. The company stated its system offers nearly 30 percent better cell degradation performance over a 20-year operational life compared to many current lithium-ion alternatives.
This lower degradation rate can reduce or eliminate future augmentation requirements, meaning operators may not need to add additional battery units over the project’s lifespan to maintain its original storage capacity.
By eliminating many of the components associated with active cooling—parts that typically require routine maintenance, repair, and replacement—the system is projected to have lower overall operations and maintenance (O&M) costs.
To deliver long-term savings
“From day one, we have believed that sodium-ion will be the winning technology for grid-scale storage, which is absolutely essential to meet increasing demand from hyperscalers and AI,” added Mossburg.
He noted that Jupiter Power “deeply understands the need to invest in and deploy technology solutions that will deliver long-term financial and operational savings.”
Mike Geier, Jupiter Power’s Chief Technology Officer, framed the agreement as part of a broader strategy.
“Jupiter Power is excited to support domestic battery energy storage manufacturing as we continue to increase the deployment of firm, dispatchable energy when and where it’s most needed,” Geier concluded. He described Peak Energy as a “first mover in domestic sodium-ion technology.”
The agreement serves as a validation of Peak’s scalable, drop-in solution and supports its efforts to build US’ domestic sodium-ion supply chain.
US-based Peak Energy, a company focused on developing giga-scale energy storage technology for the grid, has announced a significant, multi-year agreement with Jupiter Power, a prominent developer and operator of utility-scale battery energy storage systems.
Under the terms of the phased agreement, Peak Energy will supply up to 4.75 GWh of its sodium-ion battery energy storage systems (ESS). These systems are slated for deployment across Jupiter Power’s projects between 2027 and 2030.
“Deploying the world’s largest sodium-ion energy storage system with one of the nation’s top Independent Power Producers proves that sodium is ready for today and will dominate the future,” noted Landon Mossburg, CEO and Co-Founder of the energy firm.
The total contract value could exceed $500 million, representing a notable milestone for the sodium-ion storage sector.
The agreement’s initial phase stipulates the delivery of approximately 720 MWh of storage capacity in 2027. This single delivery is set to be the largest announced deployment of sodium-ion batteries to date.
Beyond this, the deal includes a substantial capacity reservation option for Jupiter Power, covering a further 4 GWh of Peak’s systems for the 2028-2030 timeframe.
Fully passive design
Jupiter Power’s selection is based on the specific operational and financial metrics of Peak’s proprietary sodium-ion (NFPP) system, which the company launched shortly before this announcement.
A central feature of the technology is its fully passive design, which eliminates the need for active cooling systems. This design choice results in a significant reduction in auxiliary power use, up to 97 percent, and enables safer operations.
These technical specifications are expected to translate into a more favorable total cost of ownership. The company stated its system offers nearly 30 percent better cell degradation performance over a 20-year operational life compared to many current lithium-ion alternatives.
This lower degradation rate can reduce or eliminate future augmentation requirements, meaning operators may not need to add additional battery units over the project’s lifespan to maintain its original storage capacity.
By eliminating many of the components associated with active cooling—parts that typically require routine maintenance, repair, and replacement—the system is projected to have lower overall operations and maintenance (O&M) costs.
To deliver long-term savings
“From day one, we have believed that sodium-ion will be the winning technology for grid-scale storage, which is absolutely essential to meet increasing demand from hyperscalers and AI,” added Mossburg.
He noted that Jupiter Power “deeply understands the need to invest in and deploy technology solutions that will deliver long-term financial and operational savings.”
Mike Geier, Jupiter Power’s Chief Technology Officer, framed the agreement as part of a broader strategy.
“Jupiter Power is excited to support domestic battery energy storage manufacturing as we continue to increase the deployment of firm, dispatchable energy when and where it’s most needed,” Geier concluded. He described Peak Energy as a “first mover in domestic sodium-ion technology.”
The agreement serves as a validation of Peak’s scalable, drop-in solution and supports its efforts to build US’ domestic sodium-ion supply chain.
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