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Google just spent $1B on Form Energy's battery that runs on rust. The price? A game-changing $33 per kWh.

2026-02-27 · 00:00 UTC ·1 min read

Brief

Google's purchase of a roughly $1 billion, 300 MW / 100‑hour (30 GWh) iron‑air battery from Form Energy for its Pine Island data center implies an all-in capital cost near $33.33/kWh. The iron‑air system uses reversible rusting (iron + oxygen) to deliver long‑duration storage, aiming to beat lithium‑ion on multi‑day firming costs and target ~$20/kWh commercially.

Why it matters

Google committed about $1.0 billion to buy a 300 MW, 100-hour iron‑air battery (30,000,000 kWh / 30 GWh) from Form Energy for its Pine Island data center, implying an all-in capital cost of ~ $33.33 per kWh.

Key details

  • The $33/kWh implied price substantially undercuts projected 2026 utility-scale LFP costs ($80–$140/kWh) and current Tesla Megapack pricing ($280–$327/kWh); Form Energy's long-term commercial target is ~$20/kWh. Iron‑air stores energy by reversible rusting (iron + oxygen), using cheap, abundant materials to enable low marginal cost for added hours.
Source evidence

title: Google just spent $1B on Form Energy's battery that runs on rust. The price? A game-changing $33 per kWh.
contenttype: article
published: 2026-02-27T00:00:00
sourceurl: https://www.reddit.com/r/energy/comments/1rfvzvd/googlejustspent1bonformenergysbatterythat/

word_count: 212

Google just spent $1B on Form Energy's battery that runs on rust. The price? A game-changing $33 per kWh.

Google recently committed approximately $1 billion to a massive 100-hour iron-air battery system from Form Energy for its Pine Island data center. This transaction sets a major financial benchmark for long-duration energy storage. Here is the breakdown of the unit economics:

-
Total Energy Capacity:The system is rated at 300 MW with a 100-hour discharge duration, totaling30,000,000 kWh(30 GWh). -
Total Investment:~$1,000,000,000. -
Calculated Unit Cost:At $1 billion for 30 million kWh, the all-in capital cost is approximately$33.33 per kWh.

Market Comparison This $33.33/kWh price point significantly undercuts traditional storage technologies:

-
Lithium-ion (LFP):Projected utility-scale costs for 2026 are between$80 and $140 per kWh. -
Tesla Megapack:Current utility-scale pricing ranges from$280 to $327 per kWh. -
Future Targets:While this deal reflects a "green premium" for early hyperscale deployment, the long-term commercial goal for iron-air technology is$20 per kWh.

The Technology Advantage The system uses "iron-air" chemistry, which literally breathes in oxygen to rust iron pellets and release electrons. Because iron, water, and air are abundant and cheap, the marginal cost of adding storage hours is much lower than lithium-ion, making it the ideal solution for "firming" renewable energy during multi-day weather lulls.