Long-duration and alternative energy storage
Long-duration storage runs past the four-hour lithium block: Form Energy’s iron-air battery discharges for 100 h, Energy Dome’s CO2 Battery for 8-24 h and Sumitomo Electric’s vanadium flow for 3-10+ h. Peak Energy brings sodium-ion with 4.75 GWh ordered or reserved by Jupiter Power.
| Duration | Data center offer | ||||||
|---|---|---|---|---|---|---|---|
| Form Energy | — | 100 h | — | — | 31.51 | Yes | 2026-11-11 |
| Peak Energy | Sodium-ion | 4-12 h | — | — | 4.751 | — | 2026-11-11 |
| Hydrostor | Mechanical | 8 h | — | — | 41 | — | 2026-11-11 |
| Invinity Energy Systems | Vanadium flow | 4-18 h | 1.21 | — | 0.0753 | — | 2026-11-11 |
| Alsym Energy | Sodium-ion | — | — | — | — | Yes | 2026-11-11 |
| Energy Dome | — | 8-24 h | — | — | — | Yes | 2026-11-11 |
| Energy Vault | — | — | — | — | — | Yes | 2026-11-11 |
| Eos Energy Enterprises | Zinc | 4-16+ h | — | — | — | — | 2026-11-11 |
| ESS Inc | Iron flow | 10 h (SRP project) | — | — | — | — | 2026-11-11 |
| Hithium | LFP | 4 h | 6.251 | — | — | Yes | 2026-11-11 |
| Rongke Power | Vanadium flow | 4-5 h | — | 3.51 | — | — | 2026-11-11 |
| Sumitomo Electric | Vanadium flow | 3-10+ h | — | — | — | — | 2026-11-11 |
Chemistry, hours and project scale
How we read the numbersFlow batteries scale hours with tank size: Invinity and Rongke Power sell vanadium flow, Rongke with more than 3.5 GWh connected in China. ESS Inc builds iron flow and Eos zinc batteries rated for 4 to 16+ hours.
Mechanical stores go bigger still: Hydrostor’s Willow Rock compressed-air plant is 500 MW / 4,000 MWh. For sodium-ion cells, compare Peak Energy and Alsym.