Key data
| Regulation | Resolution of March 10, 2026, General Directorate of Energy Policy and Mines |
|---|---|
| BOE Publication | May 4, 2026 |
| Entry into force | March 10, 2026 |
| Project holder | Molinos del Ebro, SA |
| Location | Rueda de Jalón, Zaragoza |
| Photovoltaic module | El Tollo — 45 MW installed capacity |
| Storage module | El Tollo — 5 MW with batteries |
| Existing wind farm | El Tollo — 50 MW (already operational) |
| Total complex capacity | 100 MW (wind + solar + storage) |
| Category | Energy / Renewables |
| Reference framework | National Integrated Energy and Climate Plan (PNIEC) |
| BOE Reference | BOE-A-2026-9684 |
Molinos del Ebro SA takes the first formal step to expand the El Tollo complex in Rueda de Jalón with a photovoltaic plant of 45 MW and a battery storage system of 5 MW. The Resolution of March 10, 2026 from the General Directorate of Energy Policy and Mines grants preliminary administrative authorization, enabling the start of the process that will culminate with the construction and commissioning of the facilities.
The strategic key to the project is hybridization with the already operational El Tollo wind farm of 50 MW: instead of building new evacuation infrastructure, the photovoltaic module and battery system will share the existing grid connection, which reduces costs and accelerates implementation timelines.
What does this regulation establish?
The resolution grants Molinos del Ebro, SA the preliminary administrative authorization for three differentiated elements that will form part of the El Tollo complex:
| Element | Installed capacity | Technology | Status |
|---|---|---|---|
| El Tollo photovoltaic module | 45 MW | Solar photovoltaic | New — preliminary authorization granted |
| El Tollo storage module | 5 MW | Batteries | New — preliminary authorization granted |
| Evacuation infrastructure | — | Shared with wind | Existing — usage optimized |
| El Tollo wind farm | 50 MW | Wind | Already operational |
Preliminary administrative authorization is the first link in the administrative process in Spain for electrical generation facilities. It does not enable construction: for that, a second resolution is needed (construction authorization) and, subsequently, operating authorization before commercial operation.
The project is framed within the objectives of the National Integrated Energy and Climate Plan (PNIEC), which contemplates the massive deployment of photovoltaic energy and the incorporation of storage systems to provide flexibility to the electrical system and reduce renewable energy spillage.
Economic and operational impact
Solar-wind hybridization with storage is a model that the Spanish energy sector is increasingly adopting for its concrete economic and operational advantages:
- Leveraging the existing grid connection: The El Tollo wind farm of 50 MW already has a connection point and grid access permits. Adding 45 MW photovoltaic and 5 MW batteries to that infrastructure avoids the costs and timelines associated with requesting a new connection point, which in Spain can exceed 3-5 years at some nodes.
- Complementarity of generation profiles: Wind generation occurs preferentially during nighttime and windy hours, while photovoltaic generation occurs during central hours of the day. The combination of both technologies increases the hours of use of the evacuation infrastructure and improves the predictability of the generation profile.
- The 5 MW storage adds flexibility: Batteries allow energy generated during low-price or high-production moments to be shifted to hours of higher demand or price, improving the complex's revenues and reducing curtailment risks (spillage of unused energy).
- Alignment with PNIEC: Hybridization projects with storage have priority in regulatory objectives, which can facilitate access to green financing and public support instruments.
Who does it affect?
- Molinos del Ebro, SA: Project holder and primary affected party. Must manage the following administrative steps to advance toward construction and operation.
- Municipality of Rueda de Jalón (Zaragoza): Territory where the photovoltaic module and storage system will be implemented, with urban planning and territorial ordering implications.
- Promoters of hybridization projects in Spain: This resolution is a reference for other operators who are processing similar solar-wind hybridization projects with storage, as it consolidates the applicable administrative framework.
- Renewable investors and financiers: Obtaining preliminary authorization reduces the regulatory risk of the project and is a relevant milestone for project financing structuring (project finance).
- Network operators and system managers: The incorporation of 45 MW photovoltaic and 5 MW batteries at the existing evacuation node has implications for grid management in the Rueda de Jalón area.
Practical example
Let's imagine the process ahead for Molinos del Ebro SA after this resolution:
With the preliminary administrative authorization already in hand (granted on March 10, 2026), the company must now submit the detailed execution project to the General Directorate of Energy Policy and Mines to obtain construction authorization. Only with that second authorization can it begin construction of the 45 MW photovoltaic module and the 5 MW battery system in Rueda de Jalón.
Once the facilities are built and commissioning tests are completed, it must request operating authorization, which enables commercial operation. At that point, the El Tollo complex will have 100 MW total capacity (50 MW wind + 45 MW photovoltaic + 5 MW storage), all evacuating through the same grid infrastructure, maximizing its use and making the investment in connection already made profitable.
What should companies do now?
- Molinos del Ebro SA: prepare the execution project to request construction authorization from the