Quick Facts
- Google committed $1 billion to Form Energy for a 30-gigawatt-hour iron-air battery system capable of 100-hour storage duration
- The battery will power Google’s first Minnesota data center in Pine Island, delivering 300 megawatts continuously for over four days
- Form Energy’s iron-air technology costs $20 per kilowatt-hour, three times cheaper than lithium-ion batteries
Google has signed a $1 billion deal with West Virginia startup Form Energy to deploy the world’s largest battery system by energy capacity at the tech giant’s first Minnesota data center.
The iron-air battery system will store 30 gigawatt-hours of energy and deliver 300 megawatts of electricity for 100 hours straight. The installation dwarfs typical lithium-ion batteries, which max out at four to six hours of storage.
“For all of 2025, I believe the installed capacity added to the grid in the entire U.S. was 57 gigawatt-hours. And in one project, we’re going to install 30 gigawatt-hours,” Form Energy CEO Mateo Jaramillo said.
The battery will support Google’s new Pine Island data center, located about an hour southeast of Minneapolis. The project sits within Google’s Clean Energy Accelerator framework, which commits the company to fund 1,900 megawatts of new carbon-free generation on the Xcel grid.
Form Energy’s iron-air batteries work by pumping oxygen into cells to rust iron, releasing electrons in the process. The technology delivers only 50% to 70% efficiency compared to 90% for lithium-ion batteries, but costs just $20 per kilowatt-hour of storage.
“They’re incredibly cheap,” industry analysts note, making them viable for long-duration grid storage applications where efficiency matters less than total cost.
The batteries ship in standard 40-foot containers from Form Energy’s Weirton, West Virginia manufacturing facility. The company targets annual production capacity of 500 megawatts by 2028, when the Google project deployment begins.
Form Energy has raised over $1.2 billion in equity funding, including a $405 million Series F round led by T. Rowe Price in late 2024. The company plans to go public in 2027 after raising an expected final private round of $300 million to $500 million.
Founded in 2017 by former Tesla battery development head Mateo Jaramillo and MIT professor Yet-Ming Chiang, Form Energy represents a major bet on iron-air technology for grid-scale storage.
The deal validates long-duration storage as essential infrastructure for AI workloads and data center growth. Energy analysts see the agreement as a template for how AI infrastructure will be built in the 2030s with massive renewable farms paired with multi-day storage.
Google’s commitment eliminates fossil fuel backup needs entirely, allowing the data center to run for over four days when renewable generation is unavailable. The project could power nearly 1.5 million homes at full capacity.
Read more: Google paid startup Form Energy $1B for its massive 100-hour battery