Pembroke project marks latest milestone in clean grid stability programme

A new clean grid technology project at Pembroke is now helping keep Britain’s electricity system stable as more renewable power connects to the grid.The synchronous condenser, built by RWE at its existing Pembroke power station site, is a large rotating machine that provides clean inertia. Inertia is a vital shock absorber, helping keep the electricity system stable during sudden changes in supply or demand.

Historically these services were provided by large spinning generators at coal, gas and nuclear power stations. But as Britain transitions to cleaner sources of electricity, new technologies are needed to provide the same stability without relying on fossil fuels.

The project in Pembroke is the first of a new wave of sixteen synchronous condensers under NESO's Stability Pathfinder programme, delivering new ways to keep the electricity system reliable as more wind and solar power comes online. The stability technologies will help cut emissions, strengthen energy security, and save consumers up to £9bn in system costs over the years ahead. 

Director of Engineering at NESO, Matt Magill, said:

 “Projects like Pembroke will help reduce emissions, strengthen energy security, and save consumers up to £9bn as Britain moves towards a clean power system.

 "Through our world-leading Stability Pathfinder programme, NESO has pioneered new markets for technologies such as synchronous condensers and Britain's first grid-forming batteries. Together, they are helping replace services traditionally provided by fossil fuel power stations, while maintaining one of the world's most secure and reliable electricity systems.”

The new synchronous condensers will nearly double the existing fleet of seventeen which are already providing Britain’s network with clean inertia. NESO’s stability programme also includes the first two grid-forming batteries in the world which were connected to Britain’s transmission network last year.

This is the fourth synchronous condenser to go live in Wales and the first to be built by RWE at its Pembroke Net Zero Centre. The location brings together battery storage, carbon capture, and green hydrogen projects on the site of its gas-fired power station. 

 Chief Executive Officer of RWE Generation SE, Nikolaus Valerius, said:

"The successful commissioning of our new synchronous condenser at Pembroke is an important milestone for the project and for the wider electricity system. As more renewable generation connects to the grid, technologies like this will play an increasingly important role in maintaining a secure and reliable electricity network, supporting the Government's ambition to deliver a clean power system while strengthening resilience."

The programme currently provides 17.2 GVA.s of inertia to Britain’s electricity network. The next phase will add a further 26.9 GVA.s, more than doubling the amount of clean stability available on the system. 

 As Britain moves towards a clean power system, technologies such as synchronous condensers and grid-forming assets will play an increasingly important role in ensuring electricity continues to flow safely and reliably to homes and businesses across the country.