Spain's Return kicks off construction of 55MW/220MWh standalone energy storage project

en.Wedoany.com Reported - On September 14, European energy storage developer Return announced the completion of financing for its first batch of standalone battery energy storage projects in Spain and the official start of construction. The project consists of three standalone energy storage facilities located in the province of Biscay, with a total power of 55MW and a storage capacity of 220MWh, respectively deployed in Güeñes, Barakaldo and Lezama, and is scheduled to enter commercial operation between the summer and the second half of 2027. This project is Return's first energy storage asset portfolio in Spain to enter the construction phase.

The portfolio is internally named Orion, and all three energy storage facilities are connected to the local distribution network, primarily serving the industrial load areas around Bilbao. Return is responsible for project development, financing, construction, asset ownership and subsequent operation, while ENGIE, under a long-term contract signed by both parties, is responsible for optimizing the dispatch of battery flexibility in Spain's wholesale electricity market and ancillary services market.

In July of this year, the two parties signed a 10-year full tolling long-term flexibility agreement. At that time, the project was still in the contract and investment preparation stage, with Return holding and operating the energy storage assets and ENGIE obtaining long-term commercial use rights to the corresponding flexible capacity. Following the completion of financing and the official start of construction, the project has now moved from the long-term revenue lock-in stage to the physical engineering implementation stage.

The project construction and financing chain also includes Rabobank, CATL and Enerland. CATL participates in the supply of battery systems, Enerland participates in project implementation, and Rabobank has entered the financing structure. Return disclosed that the construction phase is expected to create approximately 50 jobs around Bilbao. The project adopts a standalone energy storage model, not directly attached to a single photovoltaic or wind farm, but participating in the electricity market and system regulation through the distribution network.

The Orion project originates from the Spanish energy storage joint venture development platform established by Return and Benbros in 2024. The two parties initially planned to develop more than 500MW of standalone energy storage projects, of which the first batch of approximately 210MW has obtained grid connection permits, distributed across 10 projects. The 55MW/220MWh Orion portfolio has become the first batch of assets in this reserve project to enter the financing and construction stage.

Based on the 55MW power and 220MWh capacity, the portfolio corresponds to approximately 4 hours of continuous discharge capability. Return's official project materials show that Orion's current status has been updated to "Under Construction," with a target commercial operation date of summer 2027. Once completed, the project will operate through a long-term fixed-fee commercial arrangement, forming a complete implementation chain of "project financing—battery construction—long-term capacity contract—market optimization."