Coalburn 1 Battery Starts Commercial Operation in Scotland at 500 MW

Scotland's Coalburn 1 project, rated at 500 MW and 1 GWh, is now running commercially on land that once served coal mining, CIP said. On the developer's own count, no larger battery energy storage system (BESS) is currently operating anywhere in Europe.

Three contracts underpin the site's income. SSE holds a 10-year optimization agreement, a capacity market contract of 15 years covers 300 MW of the plant's output, and a separate seven-year contract covers 75 MW.

The asset is jointly held. Insurer Axa IM Alts bought a 50% stake from CIP in April 2025.

CIP runs the UK BESS pipeline with Alcemi. Counting Coalburn 1, that portfolio contains seven grid-scale projects totalling 4.3 GW of power output.

Hardware for the three CIP projects in Scotland comes from e-STORAGE, the battery technology arm of Canadian Solar.

At 500 MW against 1 GWh, the installation carries one hour of duration. Fixed availability payments therefore apply to 300 MW under the 15-year term and a further 75 MW under the shorter deal, with the balance of the rating uncontracted in those two schemes.

Both ESS News and pv magazine reported the commissioning of the former mining site.