- Blackhillock in Scottland is not only Europe’s biggest operating battery storage project but also the first one to provide a special set of grid stabilisation services.
- The Blackhillock site is launching in two phases. Phase 1 comprises 200 MW, which went live on March 3 and will be followed by a further 100 MW in 2026.
Blackhillock in Scottland is not only Europe’s biggest operating battery storage project but also the first one to provide a special set of grid stabilisation services. It was procured under the electricity system operator’s Pathfinder 2 while also generating revenues from other critical services.
In February 2023, construction began on 200 MW of a 300 MW/600 MWh battery energy storage system (BESS) site in Blackhillock, Scotland. Project proponents wanted it to be the world’s first transmission system-connected BESS to offer grid stability. Rather than boost or replace wires, Blackhillock will provide full active and reactive power services.
On March 3, 2025, Zenobe, one of the UK’s leading owners and operators of transmission system-connected grid-scale batteries or so-called grid boosters, announced that Blackhillock began commercial operations as Europe’s largest battery site.
The Blackhillock site is launching in two phases. Phase 1 comprises 200 MW, which went live on Monday and will be followed by a further 100 MW in 2026.
However, the type of services it will provide is even more impressive than the project size. Blackhillock was procured under Stability Pathfinder 2, the first tender of its kind in the world to procure stability services, such as short circuit levels (SCL) and inertia, from inverter-based resources.
Four companies secured 10 contracts under the tender in April 2022 to address insufficient SCL – the amount of current flowing during faults – across Scotland. The winning bidders also committed to offer “green” inertia to balance supply and demand after events such as trips at power stations, which change system frequency. Five synchronous condensers and five battery sites secured GBP 323 million worth of contracts.
At the time, National Grid offered to pay up to EUR 6,500 ($6,852) per megavolt ampere of short circuit power per year, with the successful bids averaging around EUR 4,000/MVA. This created a strong revenue potential besides the already existing reactive power contracts for battery-based energy storage.
Now, Zenobe said that the site is expected to save consumers over GBP 170 million ($216 million) over the next 15 years. The GBP 8 million of savings from the Stability Pathfinder assumes that the contract secured for the Blackhillock project will avoid the use of combined-cycle gas turbines (CCGTs) to provide inertia and SCL.
Another GBP 164 million will come from providing balancing services and constraint management to the grid, helping reduce price volatility, and cycling the battery two times a day, with degradation over the lifetime considered.