Press Releases — Grenergy signs a 10-year financial tolling agreement for its stand-alone battery project in Oviedo

• This pioneering transaction in Spain marks an important step for Greenbox, Grenergy’s 31 GWh stand-alone platform under development across Europe.
• With a capacity of 600 MWh, Oviedo is the largest stand-alone battery project announced to date in Spain.

Madrid, February 17, 2026. Grenergy has signed a pioneering 10-year financial tolling agreement with an international utility rated Investment Grade by Moody’s for its stand-alone battery project in Oviedo, an unprecedented transaction in the Spanish market.

The tolling agreement will run for ten years, beginning in January 2028. Grenergy will remain responsible for the asset’s operation and battery trading management.

Oviedo, the flagship project of Greenbox in Spain, will have a capacity of 150 MW / 600 MWh, equivalent to four hours of storage. Construction has already begun on a site previously designated for industrial use, located next to the La Estrecha substation in La Corredoria, enabling direct and efficient grid connection. The company expects the project to begin operations in the first half of 2027.

Spain is set to become one of Grenergy’s strategic markets in the coming years. The company will simultaneously deploy both stand-alone storage projects and hybrid initiatives, further strengthening the company’s leadership in Europe’s energy transition.

Greenbox

This agreement marks another milestone in the deployment of Greenbox, Grenergy’s stand-alone storage platform in Europe, which was presented at the company’s latest Capital Markets Day in London in May 2025.

With a total pipeline exceeding 30 GWh of stand-alone battery storage, Greenbox is emerging as one of the leading storage platforms in Europe. The company is advancing projects across its key European markets: Poland (5 GWh in the pipeline), Romania (7 GWh), Germany (3 GWh), Italy (5.8 GWh), Spain (6 GWh) and the United Kingdom (4 GWh).

Recently, Grenergy has recently secured capacity agreements for 2.1 GWh in stand-alone storage projects in Poland and has received a grant of nearly €8 million from the Polish government to support other stand-alone projects (136 MWh) planned in the country.

Grenergy continues to explore opportunities to enlarge Greenbox’s pipeline and close new tolling agreements across the six European markets that are currently served by its stand-alone European platform.

Battery storage is a key investment for modernizing the electricity grid, as it allows energy to be stored during periods of high generation and released when demand increases. In this way, it helps reduce price volatility, enables greater renewable integration, improves system flexibility, and helps prevent blackouts, ultimately strengthening grid stability.

David Ruiz de Andrés, CEO of Grenergy has stated:

We are very proud of this financial tolling agreement. It’s 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.

About Grenergy

Grenergy is a Spanish multinational clean energy producer. Founded in 2007, it has been listed on the Spanish stock exchange since 2015 and currently has a market capitalization of around €2 billion. The company develops, builds, and operates photovoltaic solar plants and is a pioneer in the energy storage industry.

With a team of over 600 professionals, Grenergy operates across three key regions: Europe (Spain, Italy, Germany, Poland, Romania, and the United Kingdom), North America (United States) and Latin America (Chile, Peru, Mexico, and Colombia). Its global portfolio exceeds 75 GWh of storage capacity and 12 GW of solar power in various stages of development.

Thanks to its strong commitment to battery technology, Grenergy can deliver clean, affordable, reliable, and continuous energy—anywhere, anytime, 24/7.