GB battery buildout set a record in Q3 2026. Nine batteries came online, adding 917 MW and 1,844 MWh to the fleet, ahead of the previous record of 674 MW in Q3 2025. Total capacity reached 8.5 GW and 14.4 GWh.

Even as connections reform reshapes the grid queue, large pipeline projects continue to reach commercial operation, and they are getting bigger. Since Q1 2025, five of seven quarters have added a site of 100 MW or more, with Thurrock and Kilmarnock South at 300 MW each. Q3 2026 added Coalburn 1, which at 500 MW is now the largest battery in Great Britain. Revenues held up as buildout accelerated: the ME BESS GB index rose 23% from Q2 to Q3, while capacity grew 12%.

Some batteries reach our asset database only after a quarter ends, so the latest quarter can rise. Since our earlier articles, Q1 2026 has risen from the published 397 MW to 590 MW. Q2 2026 is unchanged at 209 MW.

For any further information, reach out to the author: shaniyaa@modoenergy.com

Key takeaways