Return and Engie sign 10-year partnership to develop three 55 MW battery storage projects in the Basque Country
Type: Partnership · Technology: Storage · Country: Spain · Capacity: 55 MW · Announced: 2026-07-20
Return and Engie have signed a ten‑year agreement to develop three battery energy storage systems (BESS) in the Basque Country, together delivering 55 MW of power and 220 MWh of storage capacity. The three BESS units will be owned and operated by Return, while Engie will provide flexibility services in the Spanish wholesale and ancillary markets. Commercial operation is targeted for the end of 2027, supporting grid balance and demand‑supply equilibrium. The deal showcases a long‑term revenue model that de‑risks investment for storage owners and expands Engie's carbon‑free energy solutions portfolio. The full‑tolling structure ensures Return receives stable income while Engie gains flexible storage capacity for its energy management activities.
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