Red Eléctrica will expand the Mirabal electrical substation in Jerez

Jerez de la Frontera, August 17, 2026. The Territorial Delegation of Economy, Finance, European Funds, and Industry, Energy and Mines in Cádiz of the Junta de Andalucía has granted prior administrative authorization and administrative construction authorization to EDISTRIBUCIÓN REDES DIGITALES DIVISIÓN ANDALUCÍA, with registered office at Avda. de la Borbolla, 5, 41004 Seville, to expand the high-voltage electrical substation Mirabal 220/66 kV 1×125 MVA. The resolution is published on Monday, August 17, 2026, in the Official Bulletin of the Province of Cádiz, number 157 (p. 2), with the file reference AT-16426/26.

The installation is located in the Industrial Estate 118, plots 40 and 41, in the municipality of Jerez de la Frontera (Cádiz). The project consists of the expansion of two 66 kV line output positions on the already existing substation, whose original installation was administratively authorized on October 20, 2020, under file AT-14126-20. That file also included the Specific Declaration of Public Utility for the execution project of the new substation, granted on May 26, 2022, which encompasses the expansion now authorized.

Regulatory context and background

The authorization is based on Royal Decree 1955/2000 of December 1, which regulates the activities of transmission, distribution, commercialization, supply, and authorization procedures for electrical energy installations, in implementation of Law 54/1997 of November 27, on the Electricity Sector, and of the current Law 24/2013 of December 26, on the Electricity Sector. Territorial jurisdiction corresponds to the Territorial Delegation by virtue of article 53 of the latter regulation and of the decrees on restructuring of Regional Ministries and territorial organization of the Junta de Andalucía.

The application was submitted on May 14, 2026 to the Territorial Delegation. Previously, on December 14, 2025, authorization had already been granted for a new 66 kV line position at the same substation under file AT-16206/25. All processing has been governed by the procedure provided for in Title VII, Chapter II, of Royal Decree 1955/2000. The file does not require a declaration of public utility for its implementation, as it is contained within an already authorized substation enclosure, nor is it subject to environmental impact assessment.

Technical characteristics of the expansion

The Mirabal substation operates at a voltage of 220/66 kV with a transformer of 125 MVA capacity. The expansion adds the following main units in the two new 66 kV line positions:

• Layout scheme: double busbar, conventional outdoor type.
• 2 three-pole busbar disconnectors without earthing switch, 72.5 kV, 1,250 A, 31.5 kA.
• 1 three-pole line disconnector with earthing switch, 66 kV, 1,250 A, 31.5 kA.
• 1 three-pole circuit breaker, 72.5 kV, 2,000 A, 31.5 kA (per bay).
• 3 current transformers, 400-800/5-5 A.
• 3 voltage transformers, 66,000/√3/110/√3/110/√3/110/√3 V.
• 3 surge arresters, 66 kV, 10 kA.

Remote control and execution conditions

The substation will be equipped with an Integrated Control and Protection System (SICOP), comprising a remote system and a protection system, which will be expanded with new equipment to serve the two new bays. The substation will be remotely controlled from the Transport Support Control Center (C.C.A.T.) in Seville.

Deadlines and imposed conditions

The resolution, signed by the Territorial Delegate María Inmaculada Olivero Corral on 19 June 2026, imposes the following notable conditions:

• The planned execution period is two years from notification of the resolution.
• The works must be carried out in accordance with the submitted project, with such variations as may be authorized.
• EDISTRIBUCIÓN REDES DIGITALES ANDALUCÍA DIVISION must notify the Territorial Delegation of the completion of the works for final inspection and issuance of the operating authorization.
• The authorization becomes void if execution causes impacts on assets or rights of administrations or bodies not contemplated in the project.

Against this resolution, which does not exhaust the administrative route, an appeal for reconsideration may be lodged with the Minister of Industry, Energy and Mines of the Andalusian Regional Government within one month.

Impact on the Cádiz electricity grid

The expansion of the Mirabal substation responds to the need to reinforce the capacity for evacuating and distributing electrical energy in the Jerez de la Frontera area, one of the main industrial and demographic hubs of the province of Cádiz. The addition of two new 66 kV line bays will increase supply reliability in the area and support the growth in electricity demand linked to the development of the Polígono Industrial 118 and surrounding municipalities. Red Eléctrica, through its subsidiary EDISTRIBUCIÓN REDES DIGITALES, thus continues its investment in the modernization and expansion of high-voltage infrastructure in Andalusia.

Source: Official Gazette of the Province of Cádiz, issue 157, 17 August 2026, Section I (General Provisions), p. 2 (official reference: file AT-16426/26).