Salto de Chira pumped storage hydro plant:  a system level solution to avoid curtailment in Gran Canaria 

Gran Canaria is facing structural curtailment and grid saturation due to rapid growth in solar and wind generation. Between January and May 2025, renewable curtailment reached 19%, with peak months exceeding 24%. At the same time, 61% of the island’s substations report zero available connection capacity. These constraints limit citizen-led‑led and private projects and weaken investor confidence, highlighting the urgency for a large‑scale flexibility solution. 

The strategic role of Salto de Chira 

The Salto de Chira pumped storage hydro plant, developed and operated by Red Eléctrica de España (REE) together with the Gran Canaria Island Energy Council (CIEGC), is the island’s flagship flexibility and storage project. It is designed to absorb surplus renewable production and deliver essential system stability in an isolated grid. 

Construction began in February 2022, and the plant is expected to be operational in 2027. With 200 MW of power and 16 hours of storage, it will become the first large‑scale energy storage facility in the Canary Islands. The project received 90 million EUR from the European Regional Development Fund (ERDF) and will be connected to the 220/66 kV Santa Águeda substation through a 20 km, 220 kV transmission line. 

Pumped hydro provides over 90% of global long duration storage capacity, making Salto de Chira a mature, reliable‑duration storage capacity, making Salto de Chira a mature, reliable and proven solution. By enabling a 37% increase in renewable penetration, the project will substantially reduce curtailment and cut annual CO₂ emissions by around 20%. 

The system uses the existing Chira and Soria reservoirs, linked by an underground hydraulic circuit. The Soria reservoir acts as the lower basin, while Chira serves as the upper one. Surplus solar and wind energy pumps water uphill for later release through turbines when renewable output drops or demand rises. 

Main system benefits 

• Higher renewable penetration: Energy storage will allow solar and wind generation to increase by 51% to 70%, eliminating most curtailment events. 

• Avoided curtailment and improved investor confidence: Around 20% of renewable energy currently lost due to grid constraints will be recovered. 

• Grid stability and security of supply: The plant will provide inertia, voltage support and frequency regulation, critical services for an isolated, non-interconnected system. 

• Integration into the Eco Island vision: Salto de Chira supports broader goals for energy sovereignty, local industry development and climate resilience. 

Technical and environmental improvements 

Following CIEGC’s interventions, the final design incorporates major enhancements compared with the original 2012 proposal. These include extensive underground construction, tunnels, a cavern for hydraulic equipment and buried sections of transmission lines, to minimise visual and landscape impact. A larger desalination plant ensures sufficient water for pumping operations and provides surplus for agricultural use. Additional measures include ecological restoration, the removal of invasive species, and optimised access and tunnel designs to reduce surface disturbance. 

Adaptation, environmental restoration, and social dimension 

Salto de Chira is not only a major mitigation project through long-duration energy storage; it is also a significant adaptation measure for the island. The system will provide 1 000 000 m³ of surplus water to support agriculture, wildfire prevention, reforestation and drought resilience. At the same time, the project is enabling the largest environmental restoration programme currently underway in the Canary Islands, replacing invasive species with 14 endemic plant species characteristics of the island’s ravines. This ecological restoration is irrigated using reclaimed water from neighbouring districts, reinforcing a circular and resource-efficient approach.  

The initiative includes strong social and economic components. Two community coordinators ensure ongoing dialogue with local residents during construction, helping to minimise disruption. Economically, the project is expected to create around 3 500 green jobs and generate approximately 122 million EUR in annual savings for the island’s electricity system. 

This best practice is extracted from our publication ‘Sustainable Regions in Action‘. Discover more best practices here!