Welsh Power is to provide National Grid ESO with inertia thanks to the installation of a synchronous condenser and flywheel at its site at Rassau, Wales.
Having been awarded a contract to provide inertia earlier this year – with £328 million of contracts awarded to five companies including Drax and Statkraft – the company is now working with its project development and finance partner, Quinbrook Infrastructure Partners, to install the technology.
Traditionally, inertia – which is vital to the stability of the grid – has come from the kinetic energy in the moving parts of large generators while they are providing electricity to the grid.
However, all of the companies that won the stability contracts are either modifying existing assets or building new assets to provide stability services from inertia, without having to provide electricity.
Welsh Power is expecting its new plant to be operational by autumn 2021, with site clearance work having started last week.
Chris Wickins, director of grid services at Welsh Power, said that it was a “major milestone” for UK grid stability and comes from a “fantastic collaboration” between Welsh Power, Quinbrook, National Grid ESO, Siemens and Western Power Distribution.
“Within 15 minutes of an instruction, our facility can provide approximately 1% of the inertia needed to operate the grid safely - with zero emissions," Wickins said.
National Grid ESO has already started to receive inertia from Drax as part of the contracts, with the company using its Cruachan Power Station for the service.
As part of this, one of the generating units of the Cruachan hydroelectric pumped storage plant has been contracted to provide support services such as inertia to help the security of the grid.
Julian Leslie, head of networks at National Grid ESO, said: “It’s great to see the next step in our grid stability contract with Welsh Power.
“Our contracts for stability services are cheaper and greener, reducing emissions and saving money for electricity consumers – and are a huge step forward in our ambition to be able to operate the GB electricity system carbon free by 2025.”