In Development
Natrium
TerraPower
Sodium-cooled fast reactor with integrated molten salt energy storage, enabling flexible output from 345 MWe to 500 MWe peak.
Form EnergyIron-Air Multi-Day Battery
Active
A grid storage system built from modules the size of a washing machine, each filled with iron electrodes and a water-based alkaline electrolyte. Discharging oxidises the iron with oxygen drawn from the air; charging reverses the reaction and turns the rust back into metallic iron. Because the active materials are iron, water and air, the cost per kilowatt-hour is a small fraction of lithium-ion's, which is what makes 100-hour duration economic. Systems are assembled into multi-acre installations sized from megawatts to hundreds of megawatts.
Latest update Sep 15, 2026
01
Current status
In production at Form Factory 1, which employed more than 450 people in Weirton as of a September 9, 2026 hiring sprint. The first commercial system at Great River Energy in Cambridge, Minnesota is still completing (remaining modules awaited; COD targeted end of 2026). The 80+ GWh order book delivers from 2027, and factory output is allocated into late 2028 or 2029
02
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