UK developers seek consent for 36 GWh Fearna Pumped Hydro project

SSE and Gilkes Energy have applied for planning consent to build a 1.8 GW/36 GWh pumped hydro energy storage (PHES) project in the Scottish Highlands.

Plans for the Fearna PHES project would see the developers leverage existing hydro infrastructure near the proposed site in Glengarry, around 65 km from tourism hub Fort William.

The proposed development would use reservoir storage for a neighboring conventional hydro generation plant, which would be transferred via underground tunnel system to the Fearna reservoir above. The lower reservoir, Loch Quaich, was dammed in the 1950s to create storage for the 19 MW Quoich Hydro. It is one of the largest storage reservoirs in the United Kingdom. Planning documents show the developers expect the Fearna project will need around 11% of the available storage in Loch Quaich to fill its upper reservoir.

Fearna is being developed as joint venture following an agreement between SSE Renewables and Gilkes Energy, announced in July 2024. Gilkes Energy will lead project development under a developer services agreement with SSE Renewables.

In a press release, Gilkes Energy managing director Carl Crompton said the project could offer “substantial system and consumer benefits” by reducing wind curtailment costs and the need for costly gas generation.

Crompton added that Gilkes Energy is “working closely” with the UK government and regulator Ofgem on the development of an LDES cap and floor mechanism, which is expected to go live in 2025.

“The cap and floor model has already proven successful in attracting private investment for interconnector projects, and we expect it will similarly unlock financing for [pumped storage hydropower] projects like Fearna in 2025,” said Crompton.

The Fearna PHES is the latest in a line of pumped hydro projects announced in the United Kingdom following 40 years of relative inactivity. There are currently only four operating pumped storage hydro facilities serving Great Britain’s electricity grid, all commissioned between 1963 and 1984.

Activity has been increasing. In 2020, the Scottish Government granted SSE Renewables consent to develop the 1.5 GW/30 GWh, Coire Glas project – first approved as a 600 MW scheme in December 2013. Gilkes Energy is also developing a 1.8 GW/ 40 GWh pumped hydro storage project at Loch Earba.

Other major projects in the pipeline include a 1.5 GW project on Loch Awe, the longest freshwater loch in Scotland. Developer ILI Group lodged a Section 36 planning application to the Scottish government the project in July 2024.