Technology group Wärtsilä will supply a 68-megawatt (MW) battery energy storage system in Lerwick, Shetland, under an Engineered Equipment Delivery (EEQ) contract to Zenobē, the UK’s leading owner and operator of grid-scale battery storage. Known as The Shetland Standby Project, the initiative will enhance energy security, reduce emissions, and support the islands’ transition to a cleaner, more resilient power system. The project is scheduled to go live in 2026. The order was booked in Q2, 2025.

The battery system will enable the Lerwick Power Station to move into a standby role, cutting fossil fuel use and helping integrate more renewable energy from Shetland’s abundant wind resources. In the event of an outage or planned maintenance on the transmission line to mainland Scotland, the battery energy storage system will maintain uninterrupted power to Shetland’s homes and businesses.

The battery system features a range of innovative technologies: it will deliver Distribution Fault Ride Through (DFRT) capabilities and standby solution services to support Shetland’s mainland interconnector. These capabilities ensure grid stability in the face of transmission faults by keeping the system powered without interruption.

“As European grids grow increasingly interconnected and interdependent, projects like this signal the importance of energy storage for grid stability,” said Tamara De Gruyter, President, Wärtsilä Energy Storage and EVP, Wärtsilä. “With the advanced and proven capabilities of the GEMS platform, Wärtsilä is helping future-proof the grid with battery systems that can react in microseconds to any type of system disturbance, to maintain security of supply for Shetland.”

Wärtsilä has been contracted by Zenobē to deliver 68 MW / 130 MWh of capacity to the Shetland Standby Project in Shetland Islands, Scotland. © Wartsila

Wärtsilä’s GEMS Digital Energy Platform will manage the battery system’s real-time performance, ensuring fast, intelligent responses to fluctuations in supply and demand. With a power output that exceeds Shetland’s local load, the system will provide a crucial buffer against grid instability, enabling a secure and decarbonised energy future for the islands.

“This project combines a battery with an AC chopper in Shetland and will maintain security of supply, ensuring homes and businesses continue to receive the power they need in the event of a transmission system outage, while reducing emissions and utilising more renewables in Shetland,” said James Basden, Zenobē Founder Director. “It marks an important step in the islands’ transition to a clean and resilient energy system, and we’re proud to bring our battery expertise to a project that will reduce reliance on fossil fuels on the island network.”

The Shetland Standby Project marks the third major battery partnership between Wärtsilä and Zenobē. The 200 MW / 400 MWh project in Blackhillock, Scotland, went live in March 2025 and will be one of the largest operating battery energy storage systems in Europe and the first in the world to provide synthetic inertia services. A 300 MW / 600 MWh project in Kilmarnock, Scotland, is also in development.

The Shetland Standby Project will use Wärtsilä’s Quantum energy storage technology and will be supported by a 15-year long-term service agreement (LTSA) to ensure reliable, efficient performance throughout its lifespan.
Source: Wärtsilä