Zenobē,  the UK’s leading owner and operator of grid-scale batteries on the GB transmission network, has announced that their 300MW Battery Energy Storage System (BESS) in Kilmarnock, Scotland, has begun commercial operations.  

The site has gone live in just under two years after financial close was announced and construction began in January 2024. Kilmarnock South’s go live comes just 10 months after Zenobē’s 200MW Blackhillock BESS entered operation in March 2025.    

Kilmarnock South is part of Zenobē’s £1bn investment into battery storage and clean transportation in Scotland, with 1.3GW of storage assets now operational or in construction across the country. Today’s launch takes the company’s operational capacity in the UK to 731MW, with a further 568MW/1230MWh currently under construction.  

The site, strategically located near several offshore windfarms, will also provide Stability Services, supporting a more efficient and resilient energy network as renewable generation continues to scale. It will be only the second BESS in the UK to deliver this capability using grid-forming inverters, following Zenobē’s Blackhillock BESS, which came online in March last year.  

Zenobē has worked with Wärtsilä supplying their Quantum energy storage system technology, Omexom provided Balance of Plant works and EDF Energy acting as the Route to Market provider for the site. Kraken’s platform will support EDF’s energy trading by managing the control and dispatch of energy.  

As the site goes live, Zenobē will continue to work with the local community through its Community Benefit Fund, administered by Foundation Scotland, supporting education and training opportunities in the area.  

Commenting, Zenobē Founder Director James Basden said:  “Kilmarnock South is a landmark moment for Scotland - a world first, subsidy free battery that will reduce energy bills and strengthen Britain’s energy security. This battery will contribute towards ending the absurd waste of clean Scottish wind power.”   

“We’re incredibly proud of what the Zenobē team and our supply partners have achieved. Reducing bills for consumers nationwide by harnessing more renewable power is a key criteria for Zenobē as we build out our battery fleet in the UK.”    

Explanation of Stability Services:   

Renewable energy sources interact with the electricity grid differently from coal and gas plants. Fossil fuelled power plants deliver certain key grid services, such as short circuit level, reactive power, and inertia, as a by-product of their normal operations. Short circuit level maintains system voltage during a fault. Inertia, which is derived from the kinetic energy stored in rotating turbines, prevents sudden changes in system frequency. Renewable power sources do not provide these services consistently so to decarbonise successfully, it is necessary to find alternative, reliable sources of grid stability – not only in the UK but worldwide.