Name of the Project
Alcántara II reversible hydroelectric pumpstation.

Location
Alcántara, Extremadura, in south-west Spain.

Project Owner/s
Iberdrola.

Project Description
This reversible pumped-storage power plant will have an installed capacity of 440 MW, allowing for reversible energy storage of 16-million kilowatt hours, equivalent to the average daily consumption of more than four-million people, while providing stability for the electricity system of up to 37 hours with the machines at 
full load.

The plant will be able to generate more than 1 000 additional gigawatt hours a year using the same water resources, thereby avoiding the emission of an estimated 355 000 t/y 
of CO₂. 

This will contribute to the decarbonisation of the electricity system through greater integration of nonmanageable renewable energies, solar and wind, providing the electricity system with greater capacity for adaptation and response.

The proposed plant will connect the lower reservoir of Cedillo and the upper reservoir of Alcántara using a double underground hydraulic circuit 900 m long, and will take advantage of the difference in level between the reservoirs of up to 108 m using two 220 MW reversible turbines.

These pumped-storage plants have two reservoirs that operate as a ‘closed loop’. 

The upper reservoir acts as a ‘giant battery’, storing potential energy in the form of water that is turbined to the lower reservoir to generate electricity when the system requires it. 

Once turbined, this water, now contained in the lower reservoir, is pumped during off-peak hours to the upper reservoir following the same route.

Potential Job Creation
Not disclosed.

Capital Expenditure
The project has received a grant of €44.9-million euros from the Institute for Energy Diversification and Saving in July 2023.

Planned Start/End Date
To be confirmed.

Latest Developments
The project obtained a favourable environmental-impact statement (EIS) in September 2024.

Key Contracts, Suppliers and Consultants
No details available.

Contact Details for Project Information
Iberdrola, tel +34 91 784 32 32 or email comunicacioncorporativa@iberdrola.es.