Key data
| Regulation | Resolution of May 4, 2026, from the General Directorate of Energy Policy and Mines |
|---|---|
| Publication | June 11, 2026 |
| Entry into force | June 11, 2026 |
| Promoter | Iberdrola Renovables de Castilla-La Mancha, SA |
| Location | Villacañas (Toledo) |
| Photovoltaic module power | 30.933 MW installed |
| Existing wind farm power | 31.45 MW installed |
| Hybrid power at connection point | 40 MW (maximum limit) |
| Category | Energy |
| File initiated | November 2022 |
| Favorable EIA | February 2026 |
| Official source | BOE-A-2026-12702 |
Iberdrola Renovables de Castilla-La Mancha has the green light to convert the Sierra del Romeral wind farm into a solar-wind hybrid installation of 40 MW at the connection point. The Resolution of May 4, 2026, published in the BOE on June 11, 2026 (BOE-A-2026-12702), grants prior administrative authorization for the photovoltaic solar module "Hybridization Sierra del Romeral", with 30.933 MW of installed power.
The file began in November 2022 and has passed consultations with more than twenty organizations, culminating in a favorable Environmental Impact Declaration (EIA) in February 2026. This prior authorization is the first formal step: construction authorization and commissioning still remain.
What does this regulation establish?
The resolution authorizes the hybridization of the Sierra del Romeral wind farm (31.45 MW) with a new photovoltaic module of 30.933 MW, resulting in a hybrid installation whose maximum power at the connection point is set at 40 MW. Although the sum of both technologies exceeds 62 MW installed, the limitation at the connection point is the key regulatory element: it determines the actual capacity for grid injection.
The authorization is conditioned on compliance with the following environmental obligations:
| Environmental condition | Detail |
|---|---|
| Perimeter vegetation screen | Minimum 5 meters width with native species |
| Shrub vegetation islands | Between 5% and 10% of total installation surface |
| Slope restriction | Prohibited to install modules on slopes exceeding 12% |
| Self-protection plan | Mandatory preparation of a plan against forest fires |
Additionally, hybridization allows reuse of the existing evacuation infrastructure of the wind farm, which avoids the need to build new lines or substations for an independent installation.
Economic and operational impact
Hybridization of renewable installations is one of the most cost-efficient strategies in the current energy sector. By sharing the already amortized evacuation infrastructure of the Sierra del Romeral wind farm, Iberdrola avoids the grid connection costs that an independent photovoltaic plant of similar size would entail, which in projects of this scale can represent a significant portion of total investment.
From an operational perspective, the limitation to 40 MW at the connection point means that the combined generation of wind and sun can never exceed that simultaneous injection threshold. This requires managing the hourly complementarity of both sources: wind generates preferentially in nighttime and winter hours, while solar does so in daytime and summer hours, which maximizes the utilization factor of the connection point.
The file, initiated in November 2022, took more than three years to obtain prior authorization, illustrating the actual processing timelines for hybridization projects of this magnitude in Spain.
Who does it affect?
- Iberdrola Renovables de Castilla-La Mancha, SA: direct promoter, obligated to comply with all environmental conditions and to complete construction authorization and commissioning procedures.
- Local administration of Villacañas (Toledo): municipality where the installation is located, with implications for territorial planning and forest fire protection.
- Renewable energy promoters studying hybridization projects: this resolution is a relevant precedent on applicable environmental conditions and processing timelines.
- Consultants and advisors for energy projects processing authorizations before the General Directorate of Energy Policy and Mines.
- Operators of existing wind farms evaluating adding photovoltaic generation to optimize their connection points.
Practical example
A promoter operating a 30 MW wind farm with connection point at 40 MW can consider a hybridization similar to Sierra del Romeral. Using the data from this resolution as reference, the scheme would be as follows:
- Install a photovoltaic module of up to ~30 MW of installed power.
- Combined power at the connection point is limited to the 40 MW already contracted: no need to expand grid access.
- Must provide a perimeter vegetation screen of at least 5 meters with native species, reserve between 5% and 10% of the surface for shrub islands, avoid areas with slope exceeding 12%, and prepare a self-protection plan against forest fires.
- The prior authorization file may require more than three years of processing, according to the Sierra del Romeral precedent (November 2022 - May 2026).
This model allows the promoter to increase annual generation without additional grid access costs, improving the profitability of the existing connection point.
What should companies do now?
- If you are Iberdrola Renovables de Castilla-La Mancha: initiate procedures for construction authorization, which is the next mandatory step after this prior authorization. Without it, the installation cannot be executed.
- If you operate a wind farm with available evacuation capacity: evaluate the technical and economic viability of photovoltaic hybridization. This resolution confirms that the General Directorate of Energy Policy and Mines authorizes this model with defined environmental conditions.
- If you process hybridization projects: incorporate from design the four environmental conditions of this resolution (5 m vegetation screen, 5-10% shrub islands, maximum 12% slope, self-protection plan) to anticipate EIA requirements.
- If you advise renewable promoters: use the actual timelines of this file (more than 3 years from start to prior authorization) to plan realistic project schedules.
- If you are local administration in the area of influence: review territorial planning and forest fire protection instruments to coordinate with the self-protection plan that the promoter must prepare.
Frequently asked questions
What is a solar-wind hybrid installation and how does the 40 MW limit work?
A hybrid installation combines two renewable generation technologies (in this case, wind and photovoltaic) that share the same connection point to the electrical grid. In the case of Sierra del Romeral, total installed power exceeds 62 MW (31.45 MW wind + 30.933 MW photovoltaic), but the maximum power that can be simultaneously injected into the grid is limited to 40 MW. This means that when both sources generate at full capacity at the same time, the system must manage the surplus or reduce production from one of them.
How long does it take to process a prior authorization for hybridization like this?
The Sierra del Romeral file was initiated in November 2022 and prior authorization was granted by resolution of May 4, 2026, which represents more than three years of processing. During that period, more than twenty organizations were consulted and a favorable Environmental Impact Declaration (EIA) was obtained in February 2026. This timeline is indicative for hybridization projects of similar magnitude.
What environmental conditions does the EIA require for this type of project?
The favorable Environmental Impact Declaration of February 2026 imposes four main conditions: (1) perimeter vegetation screen of at least 5 meters width with native species; (2) shrub vegetation islands occupying between 5% and 10% of total surface; (3) prohibition of installing photovoltaic modules in areas with slope exceeding 12%; and (4) preparation of a self-protection plan against forest fires.
Does prior authorization already allow construction and operation of the installation?
No. Prior administrative authorization is only the first step in the process. To be able to construct the installation, Iberdrola Renovables de Castilla-La Mancha must also obtain construction authorization. Subsequently, after completion of works, commissioning authorization will be necessary before the hybrid plant can operate and inject energy into the grid.
What advantage does hybridization have over building an independent photovoltaic plant?
Hybridization allows leveraging the existing evacuation infrastructure of the Sierra del Romeral wind farm, avoiding the costs and territorial impact of building new evacuation lines or substations. This reduces necessary investment and simplifies administrative processing, as no new grid access point is required.
Official source
Consult complete regulation in official source (BOE-A-2026-12702)
Notice: This article is purely informational in nature and does not constitute legal advice. For specific decisions, consult a qualified professional. Source: https://www.boe.es/diario_boe/txt.php?id=BOE-A-2026-12702