39.6 MW Batteries for Freya Solar Plant: The New Accelerated Framework for Renewable Storage

Key data

Renewable energy developers now have a clear precedent: adding batteries to an existing photovoltaic plant can be processed in an accelerated manner if the requirements of RD 997/2025 are met. The Resolution of July 1, 2026 from the General Directorate of Energy Policy and Mines grants Freya Solar, SLU prior administrative authorization and construction authorization to hybridize its 44 MW solar park in Carmona with a battery storage module of 39.6 MW.

The file was closed without any opposition: no consulted administration filed objections and the public information period passed without incident. That, together with access and connection permits already updated by REE since August 2025, makes this case the reference example of the new simplified procedure.

What does this regulation establish?

The resolution grants two simultaneous authorizations to Freya Solar, SLU:

• Prior administrative authorization: enables the hybridization project from the perspective of energy planning.
• Administrative construction authorization: allows physical execution of the battery module works and its evacuation infrastructure.

The project is covered by RD 997/2025, which introduced two key advantages for this type of operation:

• Exemption from environmental impact assessment for storage hybridizations in existing renewable plants.
• Simplified administrative procedure, which reduces timelines and procedures compared to the ordinary authorization process for new installations.

The evacuation infrastructure of the battery module is resolved through an underground line at 30 kV that connects to a sectioning center, leveraging existing infrastructure up to the Don Rodrigo 400 kV substation of REE. This reuse of existing infrastructure is precisely what makes the simplified procedure viable.

Economic and operational impact

For Freya Solar, SLU, hybridization represents a capacity expansion equivalent to 90% of installed photovoltaic power (39.6 MW of batteries over 44 MW of solar). This allows optimization of the generation curve, storage of surpluses during high production hours, and discharge during higher market price hours.

From the sector's perspective, the most relevant impact is the precedent set by this file:

• RD 997/2025 eliminates environmental assessment as a bottleneck, historically one of the biggest generators of delays in storage projects.
• The update of access and connection permits by REE in August 2025 demonstrates that the transmission network can adapt to these hybridizations without the need for new connection points.
• The complete absence of objections in public information and opposition from administrations reduces regulatory risk for similar future projects.

For developers with operating photovoltaic plants, hybridization with batteries under this framework can be faster and more predictable than any new generation installation.

Who does it affect?

• Developers of operating photovoltaic plants studying adding battery storage.
• Infrastructure funds and private capital with renewable assets in portfolio susceptible to hybridization.
• Technical and legal advisors processing energy authorizations before the General Directorate of Energy Policy and Mines.
• Engineering and EPC companies specialized in storage installations (BESS).
• Network operators and infrastructure managers that must update access and connection permits for hybridizations.
• CFOs and business development directors in utilities and energy companies with photovoltaic assets in Spain.

Practical example

A developer with a 50 MW operating photovoltaic plant in Andalusia wants to add a 40 MW battery system to improve its position in the intraday market. Before RD 997/2025, it needed to initiate an ordinary authorization procedure with complete environmental assessment, which could mean between 2 and 4 years of processing.

With the RD 997/2025 framework, and following the Freya Solar model:

1. It requests the hybridization covered by the simplified procedure before the General Directorate of Energy Policy and Mines.
2. It requests REE to update existing access and connection permits (without need for a new connection point if infrastructure allows).
3. It designs evacuation through an underground line to the existing sectioning center.
4. If no consulted administration presents opposition and the public information period passes without objections, it obtains prior and construction authorization in a significantly reduced timeframe.

The Freya case demonstrates that this path is viable and that the file can be closed without incident.

What should companies do now?

1. Review RD 997/2025 to verify if your existing photovoltaic plants meet the hybridization requirements that provide access to the simplified procedure.
2. Contact REE to assess whether current access and connection permits can be updated to include the battery module without need for a new connection point.
3. Analyze existing evacuation infrastructure to determine if an underground line to the current sectioning center is technically viable (as in the Freya case with the 30 kV line).
4. Prepare documentation for the authorization request before the General Directorate of Energy Policy and Mines, including the technical project of the storage module.
5. Identify administrations to consult in the procedure to anticipate possible objections and reduce the risk of delays.
6. Evaluate the impact on market strategy: hybridization with batteries changes the plant's income profile and may require adjustments in PPA contracts or intraday market participation strategies.

Official source

Consult complete regulation in official source

Notice: This article is for informational purposes only 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-2026-16733