Grid Services and Batteries

As renewable energy generation increases, new ways to maintain grid system stability are required in order for EirGrid to operate a reliable electricity system.

A synchronous compensator is an electrical device used to manage this stability. While traditional generators rely on their power turbines to provide stability, renewables don’t offer the same inertia. With a synchronous compensator, the missing weight from the turbines is replaced with a large heavy flywheel and is ready to provide stability in the event there is an electrical disturbance such as lighting strike hitting an overhead line or sudden drop or increase power demand.

While it doesn’t generate electricity itself, this machine plays a crucial role in maintaining a balanced system.

Statkraft built the first grid-scale battery in Ireland at Kilathmoy. This is an 11MW, 5.6MWh lithium-ion battery which commenced operation in April 2020.  The battery is contracted to provide DS3 System Services to the Irish Transmission System Operator, EirGrid. These are non-energy grid ancillary services which help support the grid at high levels of renewable penetration. Services include fast reserves and reactive power. The Statkraft Grid Services team in Ireland and UK has gained valuable experience of delivering a battery projects up to 25MW.

Batteries can also participate in the balancing market, helping to manage the inevitable fluctuations that occur in the energy market to account for varying forecasts of demand, wind and power plant availability. Batteries can typically deliver their full power for 0.5-4 hours, which also allows them to participate in the capacity market, ensuring that there is enough generation capacity to deal with the short term peak demand, typically seen in December each year.