Copenhagen Infrastructure Partners (CIP), acting on behalf of its Copenhagen Infrastructure IV fund (CI IV), has agreed to divest a 50% stake in its 500MW Coalburn 1 battery energy storage system (BESS) project to AXA IM Alts, the companies said in a joint statement.
The agreement will take effect upon commissioning of the site, which is currently under construction in South Lanarkshire, Scotland, and expected to come online in early 2026.
Coalburn 1 is a two-hour duration, lithium-ion battery storage facility and, once operational, is anticipated to be the largest BESS project in Europe. CIP, which made its final investment decision in December 2023, will continue to lead project delivery through the construction phase and into commissioning.
“As CIP’s development and construction portfolio of UK BESS projects continues to progress and grow, we look forward to welcoming AXA IM Alts as a new partner on our Coalburn 1 site,” said Nischal Agarwal, partner at CIP. “The delivery of Coalburn 1, alongside CIP’s Coalburn 2 and Devilla construction projects, will improve the UK’s energy security, enable more low-cost renewables to be delivered, and will act to reduce costs for British consumers through enhanced system flexibility.”
The project benefits from a 10-year optimisation agreement with SSE and a 15-year capacity market contract, providing a high level of revenue certainty, CIP said.
Coalburn 1 is part of CIP’s broader energy storage strategy in the UK, which includes two additional transmission-connected BESS projects—Coalburn 2 and Devilla—bringing the total power capacity under construction in Scotland to 1.5GW, with a combined storage capacity of 3GWh.
For AXA IM Alts, the deal marks its entry into the UK energy storage market.
“Our investment in Coalburn 1 marks a significant milestone as we enter the UK energy storage market, reinforcing our commitment to supporting the transition to a zero carbon economy,” said Mark Gilligan, head of infrastructure at AXA IM Alts. “Battery storage infrastructure is critical to achieving national energy security and unlocking the full potential of renewable energy.”
