Coire Glas achieves Gold certification under the Hydropower Sustainability Standard

IHA congratulates SSE on a global first: its Coire Glas Pumped Storage Hydropower Project in the Scottish Highlands has become the first pumped storage project anywhere in the world to achieve Gold certification under the Hydropower Sustainability Standard. This is a significant milestone — not only for SSE and for the UK's pumped storage sector, but for the entire global pumped storage industry at a moment when long-duration energy storage has never been more central to energy transition policy.

Coire Glas is a planned pumped storage development in the Great Glen, Scotland, with a proposed capacity of up to 1,500 MW and a storage duration designed to provide multi-day grid flexibility. Its Gold certification at preparation stage — assessed before construction commences — demonstrates that the HSS can and should be applied at the earliest stage of project development, embedding sustainability into project design rather than retrofitting it post-commissioning.

The certification carries particular significance in the context of IHA's 2025–2026 advocacy priorities, which place pumped storage at the centre of the clean energy transition agenda. Alongside IHA's International Forum on Pumped Storage Hydropower in Paris, the Global Alliance for Pumped Storage, and the joint IHA-Eurelectric call to the European Commission, Coire Glas's recognition provides concrete proof that the industry is not just advocating for pumped storage — it is delivering it to the highest sustainability standards.

SSE's achievement will be highlighted as a reference case in IHA's ongoing engagement with governments and regulators across Europe as a model for how pumped storage development can align with green finance frameworks, including the EU Taxonomy for Sustainable Investment and the Climate Bonds Initiative.