Sungrow Renewables, integrated into the Sungrow Group and specialized in the development and construction of clean energy projects, is promoting in the municipality of La Vall d'Uixó (Castellón) what will be the largest energy storage hub in Spain.
The plan includes three large BESS (Battery Energy Storage System) projects: BESS Cuevas, ALM Julben Solar, and ALM Vadux Solar, all linked to the Vall D'Uxo 220 kV transmission node of Red Eléctrica de España.
The initiative also includes a collector substation with shared evacuation infrastructures, designed to optimize the connection of the three storage systems to the national electricity system and enable large-scale renewable energy storage, as detailed by the company in a statement.
Together, the three projects reach an installed capacity of 171.5 MW and a storage capacity of 726.4 MWh. The plants, planned for plots near the Vall D'Uxo 220 kV substation, already have urban compatibility from the City Council.
BESS Cuevas has a favorable environmental impact report through a resolution published in the BOE in August 2025. The three developments have obtained access and connection permits from Red Eléctrica and have completed the necessary technical adaptations for their integration into the common infrastructures.
Currently, the administrative processing is at a key stage. The file is progressing, and the next steps will be obtaining the Prior Administrative Authorization (AAP) and the Administrative Construction Authorization (AAC), which depend on the General Directorate of Energy Policy and Mines of the Ministry for Ecological Transition and the Demographic Challenge.
The company emphasizes that the granting of these authorizations will allow the construction phase of facilities called to play a "relevant" role in the deployment of energy storage in Spain, a technology considered essential to facilitate the massive integration of renewables and advance towards a more flexible, efficient, and decarbonized electricity system.
As highlighted by the CEO of Sungrow Renewables in Western Europe, Daniel Sánchez, "this project represents a long-term commitment to the development of advanced energy infrastructures in Castellón and the Valencian Community". "In addition to facilitating the integration of new renewable capacity, it represents a strategic investment in storage technologies that will be decisive in guaranteeing the security of supply and the competitiveness of the electricity system in the coming years," he added.
Contribution of the hub to the electricity system
The facilities have been designed to store electrical energy using lithium iron phosphate (LFP) batteries and feed it into the grid during periods of highest consumption, promoting the integration of renewables, system stability, and the management of variability associated with these generation sources.
In strategic terms, the entire hub aligns with the objectives of the PNIEC and the national roadmap to expand energy storage capacity, considered critical infrastructure for the Spanish energy transition, especially after the episode of the well-known "general blackout" in April 2025.
The PNIEC 2023-2030, approved by the Government in 2024, raises the energy storage target to 22.5 GW of installed capacity by 2030, compared to the 20 GW included in previous versions of the plan. This increase is considered key to achieving 81 percent of electricity generation in Spain from renewable sources by 2030.
In parallel, the ALM Julben Solar and ALM Vadux Solar projects continue their processing before the General State Administration after obtaining grid access and connection permits from Red Eléctrica in April 2024, and are awaiting the environmental impact report. ALM Julben Solar has an access capacity of 58 MW for charging and discharging operations, while ALM Vadux Solar has 52 MW for generation and consumption.
Over the past few months, both projects have adjusted their evacuation infrastructures to be integrated into a coordinated scheme along with BESS Cuevas, sharing strategic connection elements to the transmission grid.
BESS Cuevas assumes a central role within the complex by acting as the backbone project for common evacuation infrastructures. It has 55 MW of generation power and 220 MWh of storage capacity.
The file for this project incorporates the latest modifications derived from the 2025 environmental resolution, which include the redistribution of the storage plant and adaptations in the Promotores Cuevas Electrical Collector Substation to comply with the established conditions.
The 220 kV underground line that will connect to Red Eléctrica's Vall d'Uixó 220 kV substation maintains the initially planned configuration, while the project continues to advance in the administrative authorization process before the Ministry.
Global Positioning of Sungrow Renewables
Sungrow Renewables operates in more than 20 countries in Europe, Latin America, Asia, and Oceania, and is positioned as one of the largest independent developers of renewable projects globally. The firm has consolidated itself as a benchmark in the promotion of clean energies, having developed, financed, and built facilities totaling more than 47 GW of power worldwide, as the company itself has emphasized.
The company highlights its ability to add value throughout the entire lifecycle of energy infrastructures, with a global vision and applying cutting-edge technology. Among its priorities is to continue allocating resources to new projects in Spain.
"We are confident in the Spanish market and in the evolution of the electrical system as one of the key markets for the integration of renewables, which is why we continue to bet on the development, construction, and investment in renewable assets in this territory," concluded the CEO of Sungrow Renewables in Western Europe.