Bubble Batteries Set to Transform Renewable Power Storage

A new generation of grid-scale “CO₂ batteries” is beginning a global rollout, offering long-duration energy storage that keeps clean power flowing when the sun sets or wind drops.

“This can really plug and play anywhere and help grids run on clean energy around the clock,” said Ainhoa Anda, senior lead for energy strategy at Google.

The first 20 MW system began operating in Italy in 2025, storing 200 MWh of energy by compressing and expanding carbon dioxide in a closed-loop system, with replicas scheduled for deployment in 2026 across India, the United States, and multiple Google data centre regions. Built in under two years and requiring no critical minerals or special geography, the technology offers storage lasting 10 hours or more at costs expected to be about 30% lower than lithium-ion batteries, strengthening grid reliability as renewable energy scales worldwide.