Spain's 100MW/400MWh Solar Thermal-PV Hybrid Plant Enters Public Consultation

en.Wedoany.com Reported - Spain's Official State Gazette today published the announcement initiating public consultation for the Solaben ST1 and Solaben ST6 projects, which plan to install 100 MW of battery power and 400 MWh of usable energy storage capacity (with an installed capacity of 450 MWh).

Promoted by Solaben Electricidad Uno, S.A.U. and Solaben Electricidad Seis, S.A.U., the two projects aim to hybridize the existing 50 MW solar thermal power plants by adding battery energy storage systems and utilizing the existing electrical infrastructure. In March of this year, the Spanish Directorate General for Energy Policy and Mines agreed to process the two documents jointly, applying the simplified environmental impact assessment exemption procedure for specific energy storage projects under Royal Decree 997/2025.

Each energy storage system will have 50 MW of power and 200 MWh of capacity at the grid connection point (equivalent to an installed capacity of 225 MWh), with a nominal duration of 4 hours. The projects will use 36 Hithium Power 6.25 MWh lithium-ion battery containers or equivalent equipment, connected to 15 inverters, distributed across 8 medium-voltage substations. Electricity will be transmitted via new sectionalized switchgear stations to the existing Solaben 1 and Solaben 6 substations (15/220 kV), reusing the operational output infrastructure. The total power of the hybrid plant remains limited to 62.5 MW, determined by the shared transformer capacity of the plant, with access and grid connection permits totaling 104.99 MW.

The construction budget for Solaben ST1 is €21.21 million, and for Solaben ST6, €22.03 million. Both projects are located entirely within the municipality of Logrosán (Cáceres Province), with a public consultation period of 15 working days.

This energy storage integration builds on the hybridization initiated in 2024, when both plants began procedures to integrate 4.99 MW photovoltaic plants, as previously reported by pv magazine. Those projects (Solaben PV1 and Solaben PV6) will transform each complex into a hybrid facility consisting of a 50 MW solar thermal plant and photovoltaic modules connected to the same electrical infrastructure. The Solaben platform, developed by Abengoa (now merged into Cox), includes four plants—Solaben 1, 2, 3, and 6—each with an installed capacity of 50 MW, built between 2012 and 2013 using parabolic trough technology, covering approximately 440 hectares, making it one of the largest solar thermal power plant complexes in Spain.