Engie has announced plans to refurbish the Ffestiniog pumped storage hydropower plant in Wales.

The firm has signed a construction contract with German engineering firm Voith Hydro to refurbish units 1 and 2 at the 360 MW power plant, which was first commissioned in 1963. The work will help to ensure that the plant continues to play a significant role in the UK’s energy mix, Engie said.

“This is a major commitment to infrastructure development in Wales, and confirms Engie’s position as one of the UK’s leading producers of flexible, low carbon energy,” said Wilfrid Petrie, CEO of ENGIE in the UK & Ireland.

Voith’s contract includes an option to refurbish units 3 and 4 at a later date. Design, planning and component production work are due to start immediately, while work on site is expected to start at the end of 2018. The refurbishment is due to be completed by early 2020.