The £100m investment will support further development of the Coire Glas project, which includes the deployment of long-duration electricity storage, construction of a major exploratory tunnel, support the evaluation of geological conditions


Coire Glas project will be built on the shores of Loch Lochy. (Credit: SSE)

UK-based energy company SSE has unveiled its plans to invest £100m in the proposed Coire Glas pumped hydro project, which will have a potential capacity of up to 1,500MW.

The Coire Glas project is planned to be built on the shores of Loch Lochy, between Fort William and Inverness, and is expected to entail an investment of more than £1.5bn.

SSE will proceed with detailed project design and refinement, construction planning and procurement, through 2023 and into early 2024.

The company’s £100m investment will support further development of the Coire Glas project, including the deployment of long-duration electricity storage.

It will spend around half of the investment in the pre-construction refinement phase of the project, which includes site investigation works.

The works include the construction of a major exploratory tunnel and support the project team to evaluate the geological conditions related to construction.

If approved, Coire Glas would be the UK’s first large-scale pumped storage project in the last four decades and increases the country’s electricity storage capacity by more than double.

Net Zero and Energy secretary Michael Matheson said: “Today’s announcement is a significant and important milestone on the journey towards delivering the Coire Glas project.

“If built, Coire Glas will more than double Britain’s long-duration electricity storage capacity – allowing the grid to more flexibly deploy renewable electricity.

“The Scottish Government has long been supportive of pumped hydro storage capacity, which we believe will play a key role in the energy transition and is a vital component of a more flexible, resilient and secure electricity supply.”

The Coire Glas project received planning consent from the Scottish Government in 2020.

SSE aims to make a final investment decision on the project in 2024, subject to positive development progress, and commission the pumped storage scheme by 2031.

Once completed, Coire Glas is expected to deliver 30GWh of long-duration storage.

The scheme would take excess energy from the grid and use it to pump water 500m up a hill from Loch Lochy to a large upper reservoir.

The reservoir would store the pumped water and would release them to power the grid in the event of low wind output and high customer demand.

SSE finance director Gregor Alexander said: “Coire Glas will be one of the most ambitious energy infrastructure projects the UK has ever seen and is a key component of SSE’s commitment to helping lead Scotland and the UK’s energy transition.

“The £100 million investment we have announced today will help play a crucial role in further advancing the Coire Glas project towards a final investment decision in 2024, which will enable the project to move towards construction.

“Whilst Coire Glas doesn’t need subsidy, it does require more certainty around its revenues and it is critically important the UK Government urgently confirms its intention on exactly how they will help facilitate the deployment of such projects.”