Grenergy has signed a pioneering agreement in the Spanish market: a 10-year financial tolling contract with an international utility rated Investment Grade by Moody’s for its standalone battery project in Oviedo.
The financial tolling agreement will run for ten years and will enter into force in January 2028. Under the structure, Grenergy will remain responsible for operating the asset and managing battery trading activities in the wholesale electricity market.
Oviedo, regarded as the flagship project of the company’s Greenbox platform in Spain, will have a capacity of 150 MW / 600 MWh, equivalent to four hours of energy storage. Construction has already begun on land previously designated for industrial use, located adjacent to the La Estrecha substation in La Corredoria, enabling a direct and efficient grid connection. The project is expected to enter into operation in the first half of 2027.
Spain is consolidating its position as one of Grenergy’s strategic markets for the coming years. In the country, the company will simultaneously deploy standalone energy storage projects and hybrid renewable-plus-storage initiatives, strengthening its role in Europe’s energy transition and supporting further renewable energy integration.
This agreement provides further momentum to Greenbox, the company’s standalone battery storage platform in Europe, presented during its latest Capital Markets Day held in London in May 2025.
With a total pipeline exceeding 30 GWh of standalone batteries, Greenbox is positioning itself as one of Europe’s leading energy storage platforms. The company is advancing projects in key markets where it already has a presence:
| Country | Pipeline (GWh) |
|---|---|
| Poland | 5 GWh |
| Romania | 7 GWh |
| Germany | 3 GWh |
| Italy | 5.8 GWh |
| Spain | 6 GWh |
| United Kingdom | 4 GWh |
Grenergy has recently been awarded capacity market contracts for 2.1 GWh of standalone battery storage projects in Poland and has secured a grant of nearly €8 million from the Polish government to support additional standalone projects totalling 136 MWh in the country.
The company is currently evaluating opportunities to expand the Greenbox pipeline further and to close new tolling agreements across the six countries that make up its European standalone storage platform.
Battery energy storage systems represent a critical investment in modernising electricity grids. They allow energy to be stored during periods of high renewable generation — particularly from solar PV and wind power — and dispatched when demand increases. This helps reduce price volatility, facilitate greater renewable integration, provide system flexibility and prevent blackouts, reinforcing overall grid stability.
David Ruiz de Andrés, Chief Executive Officer of Grenergy, said:
“We are very proud of this financial tolling agreement: it is the first in Spain and, I am confident, the first of many within our European standalone Greenbox platform. We intend to replicate the success of our OASIS platforms in the European market, especially in Spain, where the potential is enormous.”
