Over GBP 200 million of Planned Capital Investment to Build the UK’s Largest Synchronous Condenser Pathfinder Portfolio

Four new Scottish projects to provide over half of National Grid’s published Short Circuit Level requirement, enabling the innovative management of critical grid stability as renewables increase

LONDON– April 19, 2022Quinbrook Infrastructure Partners (“Quinbrook”), a specialist investment manager focused on renewables, storage, grid stability and related assets and businesses, announced today that it has been awarded contracts for four new synchronous condenser projects in Phase 2 of National Grid’s Pathfinder Programme (“Pathfinder Phase 2”). These additional awards follow the recently announced completion of Quinbrook’s first synchronous condenser project at Rassau in Wales which is now fully constructed and operational. The Rassau project was the second newly built synchronous condenser project in the UK (under Pathfinder Phase 1) in support of National Grid’s efforts to improve grid stability in the wake of the increased growth of intermittent renewables.

National Grid’s Pathfinder Phase 2 offers fully inflation-indexed, long-term revenue contracts in return for essential grid support services from projects like Rassau. Under Pathfinder Phase 2, National Grid has awarded 10 new contracts (worth a total of GBP 323 million) to projects which offer solutions to stability issues that arise due to rapid decarbonisation of the UK power system [1]. Quinbrook has now assembled the largest portfolio of Pathfinder synchronous condenser assets in the UK that is designed to provide vital stability services to National Grid enabling more renewables to be safely and reliably connected to the power transmission network. Quinbrook expects to take total investment in Pathfinder projects to over GBP 220 million in building the portfolio over the next 24 months.

Quinbrook and Welsh Power have been developing the four Scottish projects (located near Gretna, Neilston, Rothienorman and Thurso – collectively, the “Scottish Portfolio”) since early 2020 when work commenced to identify suitable locations, with priority given to sites adjacent to existing substations where National Grid had critical needs for new stability services. Substantially all required grid connections and land rights have been secured for all four projects with one final planning consent outstanding and expected to be secured over the coming weeks. With the award of the Pathfinder Phase 2 contracts now complete, Quinbrook will progress works towards commencement of construction during 2022 with start of operations scheduled for 2024.

Once operational, the Scottish Portfolio is expected to support the stable decarbonisation of electricity supply as the UK rapidly increases uptake of intermittent and weather dependent renewables in the drive to Net Zero [2]; by collectively providing 3,500 MVa of short circuit level (“SCL”) and 1,850 MVA.s of inertia, meeting over half of NGESO’s published SCL requirement [3]. Quinbrook will lead equipment specification and procurement and continue its policy to prioritise the use of local contractors and specialists during construction works.

“We view the UK’s ‘Net Zero’ transformation as an unprecedented investment opportunity with a diverse array of attractive thematics. Crucially, our ‘whole of system’ investment philosophy puts the emphasis on addressing critical system needs and enablers for a stable transition to a decarbonised power system. By delivering both innovative and high-impact investments such as this portfolio of synchronous condensers, we can enable more renewables to be built and reliably connected to the UK power grid thereby supporting large scale carbon emissions reduction and real progress towards Net Zero. These significant new contract awards are an excellent and timely example of how specialist investors like Quinbrook can identify truly differentiated and value-add infrastructure investments arising from the energy transition. As a firm we have moved well beyond vanilla wind and solar projects.”

Rory Quinlan
Co-founder and Managing Partner

Historically, grid stability in the UK’s power systems has been maintained by large synchronous power plants predominantly fueled by carbon-intensive coal and gas. These older fossil plants are being phased out and non-synchronous renewable generators, such as wind and solar pose new reliability challenges as they do not possess the same grid stabilising properties. Due to the rapid proliferation of renewables across the UK, National Grid launched the Pathfinder Programme to source these critical grid stability services from other technologies [4]. Once fully constructed and operational, Quinbrook’s synchronous condenser portfolio will offer these critical support services to National Grid using the well-established synchronous condenser technology which is designed to operate on a continuous 24/7 basis [5].

Keith Gains, Senior Director added, “Our expanded portfolio of synchronous condenser projects adds to Quinbrook’s recently completed investment in Rassau and in other innovative UK businesses that strategically support the energy transition in important ways, such as Flexitricity and Habitat Energy. These entrepreneurial UK businesses reinforce Quinbrook’s early strategic move into the supply of critical flexible capacity, storage and grid support infrastructure that enables more variable and weather-dependent renewables capacity to be safely accommodated on the UK power grid.

Alastair Fraser, Chief Executive of Welsh Power commented, “Success in the Pathfinder 2 tender validates the two years of hard work that our teams at Welsh Power, Quinbrook and our extended network of partners have invested to bring these nationally important developments to the point where we are ready to start construction. We consider these innovative projects an essential step towards building an effective zero carbon electricity network in Great Britain. Through the partnership with Quinbrook, Welsh Power is able to continue to build its expertise in developing these exciting new projects.


About Quinbrook
Quinbrook Infrastructure Partners (http://www.quinbrook.com) is a specialist investment manager focused exclusively on renewables, storage and grid support infrastructure and operational asset management in the US, UK and Australia. Quinbrook is led and managed by a senior team of power industry professionals who have collectively invested c. USD 8.2 billion equity in energy infrastructure assets since the early 1990s, representing a total enterprise value of c. USD 28.7 billion or 19.5 GW of power supply capacity. Quinbrook has completed a diverse range of direct investments in both utility and distributed scale onshore wind and solar power, battery storage, reserve peaking capacity, biomass, fugitive methane recovery, hydro and flexible energy management solutions in the US, UK and Australia.

About Welsh Power
Welsh Power is an employee-owned business providing development and asset management services to flexible generation, storage, and grid stability markets.

Media Contact:
Jennifer Pflieger
[email protected]
+1 (212) 446-1866



[1]: https://www.nationalgrideso.com/news/scotlands-wind-success-story

[2]: https://www.nationalgrideso.com/future-energy/projects/pathfinders

[3]: https://www.nationalgrideso.com/future-energy/projects/pathfinders/stability/Phase-2

[4]: https://www.nationalgrideso.com/news/latest-boost-stability-pathfinder-construction-flywheel-begins

[5]: https://Press.siemens-energy.com/global/en/pressrelease/siemens-energy-begins-construction-gb-stabilization-project


Skip to content