Red Eléctrica, through its Canary Island subsidiary REINCAN, has completed the adjustment to the construction project of the Chira-Soria pumped-storage hydroelectric power station after incorporating various improvements. Among the improvements noteworthy is its location, which will be  in a geologically more suitable area, and the optimisation of the layout of the desalination plant. These modifications respond to the geological and geotechnical studies carried out in 2018 and to the suggestions made by the competent administrations and social agents.

The process of identification and inclusion into the project of the improvements has been undertaken through permanent interaction with the administrations, taking into account all possible suggestions and arguments, which has enabled the best solution to be achieved with the greatest possible consensus from a global perspective. The strength of the initial project, which is due thanks to the successful completion of the first phase of the public participation and consultation process, makes the Company confident that the current phase will progress swiftly and that work can begin all authorisations and permits are in hand.

The project was designed to meet the objectives of system security, guarantee of supply and integration of renewable energy, it is an innovative engineering project that, among other things, incorporates reversible pumped-storage hydro turbine units, synchronous machines, electronic power converters, a hydraulic short-circuit scheme and an equipment control system that provides the project greater flexibility and performance.

Chira-Soria is the first industrial facility project on the Canary Islands that is designed and modelled using 5D Virtual Design and Construction methodology. It is the most modern technology available, which allows designing in 5 dimensions, the three spatial, plus time and cost. This innovative technique has allowed the design and modelling processes to be optimised, as well as improvements to be implemented quickly and safely.

This improved project, which will place the Canary Islands at the forefront of technology and innovation in this field, will have to undergo the mandatory public information process, for a period of 30 working days starting today, after which it will be in a position to receive environmental and construction authorisations and permits that enable work to start.

Main improvements to the project

Through the improvements incorporated, the caverns have moved towards Chira approximately 500m to a geotechnically more suitable area. For this reason, it is necessary to adjust the layout of the project’s underground works.

Taking advantage of this displacement, the surge tank (expansion chamber) has been located in an area which is relatively out of sight and barely stands 50 centimetres above the ground. The mouth of the access tunnel to the power station will now be located in the area of ​​Pumping Station II, reducing the environmental impact, as it eliminates approximately 500 metres of surface access, replacing it with an additional 500 metres of tunnel. In the Soria reservoir, the control and gate building has been modified in order to better blend them into landscape.

The desalination plant has been compacted to occupy less surface area maintaining all its benefits as required by the concession contract of the Island Water Board.

An essential project for the integration of renewable energy

The Chira-Soria pumped-storage hydroelectric power station, an essential infrastructure to advance towards the achievement of the new Canary Islands energy model and reduce the costs of the insular electricity system contains fundamental elements to make this energy transition a reality, whose pillar is the decarbonisation of society through the integration of renewable energy, interconnections between islands, large-scale energy storage and an improved electricity grid with a higher level of meshing. All this will provide all users with an enhanced electricity system that offers better security and guarantee of supply.

The power station will be able to produce up to 200 MW of power, which represents around 36% of the current peak demand of the island of Gran Canaria. Once commissioned, the pumping station will allow hydro storage using surplus renewable energy that cannot be integrated into the electricity system, pumping water from the lower reservoir to the upper one, so that it can be used later.

The project includes the construction of a seawater desalination plant and the associated marine construction works, as well as the necessary facilities for its connection to the transmission grid to be able to evacuate this energy into the Gran Canaria electricity system.

It also doubles the number of turbo-pumps, incorporates six power converters and the possibility of a hydraulic short-circuit scheme, thanks to which renewable energy can be integrated in a massive way throughout the full range of the power station’s operation (-220MW in pumping mode and up to 200MW in turbine mode).