In Scotland, Omexom UK created one of the United Kingdom’s largest energy storage systems on behalf of Zenobē. The Kilmarnock South BESS will help to stabilise the power supply network, reduce CO₂ emissions and facilitate the massive-scale integration of renewable energies.
©Cyrille Dupont – The Pulses
In support of the energy transition, battery storage is emerging as a vital component in modern electricity networks. In Scotland, the Kilmarnock South BESS -battery energy storage system-, designed and built by Omexom UK on behalf of Zenobē, a leading developer and operator of large scale battery energy storage systems, perfectly exemplifies this evolution.
With the country committed to carbon neutrality, the massive development of renewable energies will require improved network flexibility. Batteries can be used to store surplus electricity produced by wind farms when demand is low and restore it when production decreases. This ability to balance supply and demand in real time is key to the stability of the British energy system.
The Kilmarnock South BESS with 300 MW of power and a capacity of 600 MWh is one of the United Kingdom’s largest energy storage systems. It will contribute to the elimination of approximately 3.4 million tonnes of CO₂ during its first 15 years of operation. Connected to the 400 kV Scottish Power substation, it will play a strategic role in optimising the transmission of Scottish renewable electricity to the highest-consuming regions of England.
Large-scale engineering project
Omexom UK is the general contractor and lead designer for the project. “We were selected for the design, provision, installation and commissioning of the storage system to be connected to the national network,” says Jose Ignacio Garcia Saenz, Business Unit General Manager at Omexom UK Renewables Scotland. The business unit is responsible for the civil engineering work, horizontal directional drilling, cabling and electrical installation for the BESS complex and the 400 kV customer substation.
“We were selected for the design, provision, installation and commissioning of the storage system to be connected to the national network”
The project posed numerous technical challenges. “Completing earthworks in winter, managing the unexpected ground features, and coordinating with the multiple stakeholders were major challenges,” explains Jose Ignacio Garcia Saenz. Despite an ambitious schedule, the teams maintained the highest technical standards and adapted well to the project’s environmental constraints. All excavated earth was reused to create a new local habitat, in line with Omexom’s determination to manage the project in a sustainable way.
Sustainable commitment
Following the construction phase, Omexom will fulfil a long-term service and maintenance contract. “This preventive and corrective contract, covering an initial five-year period, may be extended for up to 15 years,” says Jose Ignacio Garcia Saenz. The aim of this follow-up is to guarantee the installation’s continuing performance and network security over many decades.
The installation entered commercial service in December 2025 and will be operational for around 40 years with reduced maintenance requirements. It will add to the resilience of the British network while facilitating the large-scale integration of renewable energies.
05/20/2026
