Electricity transmission grid facilities

In 2022, in a context of economic recovery after the pandemic but marked by other geopolitical factors in Europe, investment in the transmission grid increased to 448.8 million euros, 14.8 % higher than the previous year. These investments have contributed to integrating increased renewable energy sources, strengthening inter-island links, improving grid meshing, promoting electrification, guaranteeing security of supply, and ensuring quality of service.

It should be noted that in March 2022, the Council of Ministers approved the Electricity Transmission Grid Development Plan for 2026 at the request of the Ministry of Ecological Transition and Demographic Challenge. It constitutes a fundamental tool for guaranteeing the energy transition and establishes the transmission grid development projects that must be implemented over the coming years in order to achieve the energy objectives of national and European policy.

The main motivation of the 2021-2026 Plan is to boost renewable production and maximise the use of the existing grid, thanks to new technologies such as batteries or power electronics. The environmental dimension takes on special relevance, with the main objective of making grid development compatible with respect for our environment. The plan involves an investment of nearly 7,000 million euros to improve the transmission grid. The greatest investment effort is aimed at improving the integration of renewable energy sources, providing a clear benefit to society in terms of reducing emissions, saving electricity system costs, and activating the economy.

Throughout 2022, 326¹ kilometres of lines and 109 substation positions were commissioned, bringing the total length of lines in the national transmission grid to 45,101 kilometres, an increase of 0.7 % compared to 2021. In addition, transformer capacity increased by 725 MVA, bringing the total national transformer capacity to 94,221 MVA (0.8 % higher than in 2021).

Facilities in the electricity transmission grid in Spain

Km

Annual evolution of the electricity transmission grid in Spain

Annual evolution of the transmission grid by systems

Among the projects carried out in the transmission grid in 2022, the following are the most important, according to their geographical area of development:

Andalusia: The newly commissioned Baza 400 kV substation, together with the new Baza-Caparacena 400 kV transmission line, forms part of the initial section of the Caparacena-Baza-La Ribina axis. This series of infrastructure enhancements aims to reinforce supply quality and security, increase the capacity of the system for optimizing renewable energy use, and lay the foundations for the development and activation of both the Mediterranean Corridor (Granada-Almería) and High Speed (Murcia-Almería) railway axes.

The Palos-Torrearenillas 220 kV line has been completed, and the new Chucena 220 kV substation has been commissioned to improve the security of supply in the area. Various extensions have also been made to substations in the area (Don Rodrigo, Tabernas, Carmona, Guillena, and Puerto Real) to support the distribution grid or for the evacuation of renewable generation.

Aragon: Progress continued in reinforcing the transmission grid in various areas with the commissioning of the extensions to the Mezquita 400 kV, Mudejar 400 kV, and Valdeconejos 220 kV substations.

Balearic Islands: The renovation of the Bunyola-Inca 66 kV line has been successfully commissioned. This initiative, together with the extensions of the Torrent 132 kV and San Jorge 66 kV substations, is aimed at improving the security of supply. In addition, four new reactors have been installed at the Torrent 132 kV substation to optimise voltage control of the link to Formentera and improve the quality of supply.

Canary Islands: One of the most important projects is the Playa Blanca-La Oliva 132 kV submarine cable, which connects Lanzarote and Fuerteventura and will improve the quality and security of supply on both islands.

In Tenerife, the Caletillas-El Rosario 220 kV double circuit line, the new Caletillas 220 kV substation, and the extension of the Los Olivos 66 kV substation have been commissioned. Finally, on the island of Gran Canaria, the Santa Águeda-Arguineguín 66 kV line, the extension of the Sabinal substation by connecting the 220-66 kV fleets with the installation of a new 125 MVA transformer, and the extension of the El Tablero 66 kV substation have been completed. All of these will improve the security of supply in the area.

Castile and Leon: The extension of the Villamayor 220 kV substation has been completed in order to support the electrification needs of the high-speed rail network. At the same time, the capacity for connection and evacuation of renewable generation has been increased with the commissioning of the 400 kV substations in Segovia, Buniel, Valdecarretas, and Tábara and the extension of the Palencia 220 kV substation.

Castile-La Mancha: New bays for the evacuation of renewable energy have been commissioned at the 400 kV substations of Trillo, Belinchón, Manzanares, and Fuentes de la Alcarria and at the Brazatortas 220 kV substation. Likewise, to facilitate the transit of energy flows and the integration of renewable energy sources, the Olmedilla 220 kV substation has been extended with the installation of a new 400/220 kV transformer. With the same objective, work continues on the Olmedilla-Villanueva de los Escuderos-Trillo 400 kV line.

Catalonia: The Mangraners 220 kV substation has been extended to facilitate support for the distribution grids. At the same time, progress continues on the construction of the Mangraners-Espluga-Begues 220 kV axis. This project, together with the expansions in the 220 kV grid, will connect the Cerdá substation and the meshed grid via two connection lines to the Hospitalet and Airport substations.

Extremadura: A new ballast has been commissioned at the Almaraz ET 220 kV substation to improve voltage control in the area. The Arañuelo 400 kV substation has also been extended to supply the new Adif railway lines, and the Plasencia 220 kV and San Serván 400 kV substations have been extended to increase the capacity for integrating renewable generation in the area. Progress has also continued in the processing and work on the rest of the actions set out in the 2021-2026 Plan.

Levante: In Valencia, the new Sancho Llop 220 kV and El Serrallo 220 kV substations, together with their connection lines, will support the distribution grids and ensure supply in the area. The extension of the Morella 400 kV substation has also been commissioned, and work continues on the extension of the La Plana 400 kV substation. In the Murcia region, the Peñarrubia 400 kV substation has been extended to integrate renewable energy.

Central area: The Loeches 400 kV and San Sebastián de los Reyes 400 kV substations were extended to improve the reliability of the system. Simultaneously, work has continued to progress on the San Fernando 400-220 kV substation and on the procedures for the rest of the actions set out in the 2021-2026 Plan.

Northern area: In the Basque Country, the Güeñes-Ichaso 400 kV double circuit is under construction. This project forms part of the axis that, passing through Ichaso, will connect the west of the Basque Country (the Abanto-Güeñes axis) with the 400 kV network of Navarre (the Muruarte-Castejón axis). This axis will allow for increased power evacuation capacity and greater integration of renewable energies, as well as ensuring the committed values of exchange capacity between Spain and France. Another significant milestone in this area was the commissioning of the first DLR (Dynamic Line Rating) device on the Logroño-El Sequero 220 kV line, which aims to optimise asset use without compromising safety.

In Cantabria, the Astillero-Cacicedo 220 kV underground cable connection was commissioned. This initiative, together with the extension of the Cacicedo 220 kV substation, will strengthen the security of supply in the entire area of the city and port of Santander.

In Galicia, the extension of the Pazos 220 kV substation has been completed to facilitate the northern interconnection with Portugal. Work continues on the construction of the new line connecting the Regoelle 220 kV substation with the Mesón-Dumbría 220 kV line to increase the connection and evacuation of renewable generation.

Interconnections continue to play a key role in the energy transition to achieve greater integration of renewable energy sources and progress in decarbonisation. The strengthening of international interconnections remains a priority for the coming years in the development of the transmission grid, as highlighted in the 21-26 Plan.

The latest interconnection commissioned between Spain and France (Baixas-Santa Llogaia) at the end of 2014 doubled the electricity exchange capacity between Spain and France (from 1,400 MW to 2,800 MW), helping to reinforce the security of the two electricity systems and favouring the integration of a greater volume of renewable energy. However, despite this extension, the degree of interconnection in our country is still below the targets set by the European Union of 10 % and 15 % for 2020 and 2030.respectively.

The Spanish National Integrated Energy and Climate Plan (PNIEC) made this clear and proposed increasing the exchange capacity with Portugal to 3,000 MW and with France to 8,000 MW by means of three new electricity interconnections. The interconnection between Gatika (Spain) y Cubnezais (France) will be the first fundamentally submarine interconecction between Spain and France (“Golfo de Bizkaia” project); and two other projects across the Pyrenees².