Statkraft signs deal to buy inertia machines from GE

Statkraft has signed a deal to buy two of GE’s “rotating stabilizers” – machines purpose-built to maintain the stability of the power grid by providing inertia, frequency response and reactive power generation and absorption.

They will both be installed at a site in Keith in Moray. Statkraft won two contracts for the machines in the first ever tender for a new stability service being trialled by National Grid Electricity System Operator (ESO) covering inertia, voltage management and short-circuit level contribution.

Inertia refers to the resistance of the electricity system to sudden changes in frequency. It can only be provided by synchronous machines, such as gas and steam turbines, containing large spinning masses rotating in harmony with the frequency of the power grid.

Asynchronous generators such as wind and solar farms are unable to provide inertia, meaning the closure of old fossil fuel power stations has made the electricity system more susceptible to sharp swings in frequency.

“The rotating stabilizer solution provides a way to replace the inertia provided by traditional thermal plant generation but operating without carbon emissions”, said Guy Nicholson, head of grid integration at Statkraft UK.

“We are delighted to have reached this critical milestone in providing stability services to the grid,” added Statkraft UK managing director David Flood.

“Our project at Keith builds on our electricity market and renewables expertise and helps Statkraft deliver our vision of being a renewable energy system integrator.”

Julian Leslie, head of networks at the ESO, commented: “The GB electricity system is one of the most advanced in the world, both in terms of reliability and the levels of renewable power, and we’re really excited to be adding to that with this new approach to operating the grid.

“Our contracts for stability services with providers such as Statkraft are cheaper and greener, reducing emissions and saving money for electricity consumers. This approach is the first of its kind anywhere in the world and is a huge step forward in our ambition to be able to operate the GB electricity system carbon free by 2025.”

At the end of January, the ESO awarded ten contracts worth £328 million to five companies in the inaugural tender for the new stability service.

Statkraft also won two contracts for its Lister Drive site in Liverpool, giving it the largest number of any company. All four of its agreement will commence in April 2021 and end five years later in 2026.

Last month, the ESO released details on its plans for the second tender which will award contracts starting in July 2021 at the earliest and April 2024 at the latest and finishing by April 2030.