Spanish clean energy company Grenergy has inked a ten-year financial tolling agreement for its 150MW/600 megawatt-hour stand-alone battery project in Oviedo, Spain.
The deal has been signed with an international utility that holds an Investment Grade rating from Moody's. It marks a pioneering transaction within the Spanish market.
The Oviedo project is designed to provide four hours of energy storage capacity.
It is part of the company's Greenbox platform under development across Europe, and represents the largest stand-alone battery initiative announced in Spain to date.
Construction has already started at a site previously used for industrial purposes, located next to the La Estrecha substation in La Corredoria, ensuring a direct and efficient grid connection.
The project is expected to commence operations in the first half of 2027 (H1 2027), with the tolling agreement commencing in January 2028.
Grenergy will manage both the asset’s operation and battery trading.
Spain is recognised as one of Grenergy's key markets, where the company plans to launch both stand-alone storage projects and hybrid initiatives simultaneously.
This strategy is designed to enhance Grenergy's presence in Europe's changing energy landscape.
The Greenbox platform was unveiled during the company’s Capital Markets Day in May 2025 in London.
The Greenbox platform encompasses a pipeline exceeding 30 gigawatt-hours (GWh) of stand-alone battery storage projects, positioning itself as a leading entity within Europe.
Current progress includes projects across key European countries including Germany (3GWh), Italy (5.8GWh), Poland (5GWh), Romania (7GWh), Spain (6GWh) and the UK (4GWh).
Grenergy is actively seeking opportunities to expand Greenbox's pipeline and forge new tolling agreements across these European markets.
Investing in battery storage plays a crucial role in upgrading the electricity grid.
It enables the storage of energy when production levels are high and its release when demand rises.
This process contributes to reducing price fluctuations, facilitates increased integration of renewable energy sources, enhances the flexibility of the system, aids in preventing blackouts and ultimately bolsters grid stability.
Grenergy CEO David Ruiz de Andrés said: “We are very proud of this financial tolling agreement. It is the first of its kind in Spain and, I am sure, the first of many within our stand-alone Greenbox platform in Europe.
“We are going to replicate the success of the OASIS platforms in the European market, especially in Spain, where the potential is enormous.”
Last month, Grenergy secured capacity contracts for five independent storage projects in Poland totalling 2.1GWh.
