Spanish independent power producer Grenergy Renovables has closed a senior non-recourse financing of EUR 100 million (about US$113.75 million) for the 618 MWh Oviedo stand-alone battery energy storage system in Asturias. The transaction, announced 22 July 2026, is the first bank-backed project finance ever executed in Spain for a stand-alone BESS.
Deal Structure
Banco Santander and Sumitomo Mitsui Banking Corporation (SMBC) acted as mandated lead arrangers on the package, which includes senior debt and additional credit facilities. Oviedo already benefits from a 10-year financial tolling contract signed in February - itself the first such deal for a stand-alone Spanish BESS - which underpins revenue certainty from the project's commercial operation, expected in the first half of 2027.
What Grenergy Is Building In Asturias
Construction has begun on an industrial plot alongside Iberdrola's La Estrecha substation in La Corredoria, northern Spain. Oviedo is a flagship asset for Grenergy's stand-alone storage development platform Greenbox, which now has more than 30 GWh of BESS in development across Poland, Romania, Germany, Italy, Spain and the United Kingdom. The company is targeting Iberian ancillary services and merchant arbitrage revenue as Spain's rapid solar buildout lengthens the daily duck curve.
Why This Matters For Spain
Until this deal, Spanish BESS projects had struggled to break out of merchant-only structures because banks demanded contracted revenues that ancillary and capacity markets did not yet provide. The Santander-SMBC package validates the tolling-plus-merchant model for European storage and opens a pipeline of stalled Iberian BESS projects to bank finance. The move also lands as European battery deployment accelerates: Brookfield's $7B Aypa Power take-private and BYD's 11.3 GWh Masdar RTC contract mark the same weekly tempo.
Grenergy's Wider 2026 Book
Grenergy signed a separate 15-year, 1 TWh nighttime PPA earlier this month covering the 3.5 GWh Elena BESS in Chile's Atacama Desert, extending its cross-continent momentum in bankable storage. Oviedo builds a European counterpart to that Chile flagship and positions the developer as one of the leading independents in bringing utility-scale BESS to financial close on both sides of the Atlantic.
Reporting based on coverage from Grenergy, Renewables Now, Energy-Storage.News and MarketScreener.