ENGIE and La Caisse select GE Vernova for Dinorwig pumped storage modernisation
Published by Jessica Casey,
Editor
Energy Global,
First Hydro Company, a joint venture between ENGIE and La Caisse, and GE Ver-nova Inc. have announced the next phase of the modernisation/replanting of the Dinorwig pumped storage hydropower plant in North Wales, the UK. Under the agreement, GE Vernova is expected to replace two pumped storage units as part of First Hydro's long-term replanting programme at Dinorwig, to help extend the life of the plant for decades to come, while enhancing the plant’s reliability, availability, and performance in support of UK grid stability.
Now over 40 years old, Dinorwig is Europe’s largest pumped storage hydropower plant and is renowned for its rapid response capability, delivering up to 1320 MW of power within 12 seconds from standby, and up to 1800 MW in under a minute. With such characteristics, this plant plays a vital role in grid resilience and frequency response, providing a capacity equivalent to power around one million homes in the UK.
As majority owner and operator of the plant through First Hydro Company, ENGIE is making a significant long-term investment to extend its operational life. The wider programme includes the replacement of key plant components across all six generating units, alongside significant infrastructure upgrades.
The modernisation forms part of one of the UK's largest hydro refurbishment and replanting programme, helping to strengthen long-term grid resilience and support the integration of renewable energy in the UK's evolving electricity system. This programme is expected to extend the plant’s life by at least 25 years, to ensure continued delivery of fast, flexible low-carbon power.
“This contract marks an important milestone in our long-term investment programme at Dinorwig,” said Delphine Cherel-Sparham, Managing Director of ENGIE Hydro UK. “As majority owner and operator of the plant, ENGIE is committed to ensuring Dinorwig continues to provide the flexibility, resilience, and energy storage capabilities that the UK electricity system increasingly depends upon. Together with GE Vernova, we are investing in the modernisation of key generating units to help secure the plant's performance for decades to come.”
“This project is a strong example of how GE Vernova can bring innovation and engineering expertise to a landmark hydro asset,” said Emmanuel Mercier, GE Vernova’s Hydro Power EMEA Leader. “Dinorwig is a highly strategic facility for the UK power system, and we are proud to support First Hydro Company in strengthening the reliability and performance of this important plant.”
The announcement follows the completion of the pumped storage unit model test validation at GE Vernova’s testing laboratory in Grenoble, France. As part of its scope, GE Vernova is expected to supply the upgraded motor generators and pump turbines, alongside refurbishment of embedded parts such as the spiral case, stay ring and draft tube. The project also includes an upgraded control system for the station, as well as low-voltage, medium-voltage, and DC power supply systems. The pump turbines and motor generators were engineered respectively in GE Vernova’s Centers of Excellence in Grenoble, France, and Birr, Switzerland.
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