Amarenco doubles capacity of French BESS site through repowering

IPP Amarenco is currently repowering its Claudia battery storage asset in Saucats, Gironde, increasing the site’s energy capacity (MWh). Originally commissioned in 2024 as a one-hour BESS project under RTE’s AOLT tender and primary reserve services framework, the facility will transition from a 105 MW/100 MWh configuration to 94 MW/188 MWh – effectively doubling its storage duration to two hours.

Works commenced in July 2025. The first battery containers are scheduled for delivery in spring 2026, followed by installation, grid connection, testing, and certification phases through autumn 2026. Commercial commissioning is targeted for February 2027.

According to Amarenco, the upgrade will significantly enhance the site’s ability to deliver essential grid services, including frequency regulation, imbalance management, intraday market optimization, and grid-forming capabilities. By aligning storage duration with emerging European standards – typically between two and four hours – the “Claudia 2h” project strengthens both operational flexibility and long-term economic performance. The repowering will also extend the asset’s lifespan by approximately 15 years through the reuse of existing infrastructure.

€65 million refinancing

The upgraded facility will deploy both nickel manganese cobalt (NMC) and lithium iron phosphate (LFP) battery technologies in separate, self-contained units with dedicated power systems, enhancing resilience, safety, and operational flexibility. The increased share of LFP technology – recognized for its high safety standards and UL 9540A certification – addresses stringent industrial safety requirements. Ultimately, the site will comprise around 80 battery containers.

The repowering is supported by a €65 million refinancing, reflecting the asset’s maturity. The debt package is provided by Société Générale and Rabobank, acting as mandated lead arrangers, lenders, and LC bank, with Société Générale also serving as agent and custodian. In addition, Caisse des Dépôts et Consignations has acquired a 49% stake in the project, alongside Amarenco, which retains 51%.

“We are proud to be delivering one of Europe’s largest storage repowering projects to provide critical grid services,” said Frédéric Maenhaut, CEO of Amarenco, which reached 650 MW of installed solar capacity in 2024. “This milestone supports our 2030 roadmap, driven by disciplined portfolio execution, strategic partnerships, and regular participation in tenders. Our approach integrates all key stakeholders – financiers, storage technology providers, EPC contractors, aggregators, and offtakers – within a fast-evolving European energy market marked by continuous innovation in storage.”

The project also benefits from a long-term operating framework that provides strong revenue visibility through a tolling agreement with Engie. This structure enhances financial stability and underscores the economic viability of large-scale storage infrastructure.

From pv magazine France