• Of the 6,023 substations analyzed, 4,960 lack available capacity, representing 82.4% of the total.

  • The Basque Country and La Rioja lead in grid saturation, both at 99.2%

  • Galicia, Andalusia, and Catalonia concentrate the highest available capacity

  • 24 provinces, nearly half of the total, exceed 90% saturation in their substations

September 19, 2025

Last week, we reflected on the publication of the long-awaited distribution maps prepared by each of the main distribution companies.

This week we wanted to take it one step further. Foro Industria y Energía, in collaboration with Opina 360, has developed the first interactive map to understand the demand capacities of electrical substations across the country. This tool provides a detailed overview of the situation of 6,023 substations belonging to 19 distributors—covering 97% of the country’s supply points—and offers data both in terms of saturation and megawatts available at each of those points.

A highly saturated system

The study carried out by FIE and Opina 360 with this tool reveals that the Spanish grid is in a state of high saturation. Of the 6,023 substations analyzed, 4,960 lack available capacity, representing 82.4% of the total. This figure differs slightly from that published by AELEC (83.4%) because it includes data from more distributors, although it remains consistent. The total available capacity nationwide amounts to just over 10 GW (10,134.33 MW), but its distribution is uneven and fragmented regionally.

“With this first access capacity map, we want to make it easier for companies to quickly understand the electricity demand possibilities for their projects. We believe it is a tool of great value for industrial planning,” said Opina 360’s director, Juan Francisco Caro.

“Distributors have complied with the information requirements set by the regulator, but what was missing was a clear X-ray of the Spanish power grid to ensure that companies, administrations, and sector players have complete and transparent information for decision-making in a context marked by the need to advance industrial electrification,” Caro added.

The Basque Country and La Rioja, leading in grid saturation

The map identifies six provinces that are completely saturated, with no available capacity in any of their substations: Almería, Málaga, Albacete, Guadalajara, Álava, and Vizcaya. At the regional level, the Basque Country and La Rioja are the most strained territories, both with saturation levels of 99.2%. Aragón (95.6%), Navarre (94.1%), and Andalusia (89.5%) also show very high values. Overall, 24 provinces—nearly half of the total—exceed 90% saturation, highlighting the limited access capacity in much of the country.

When analyzing available capacity in absolute terms of megawatts, the territories with the least access margin to the grid are La Rioja, with only 6 MW, the Basque Country with 7 MW, while Castilla-La Mancha and Cantabria have 84.3 MW and 84.6 MW, respectively.

Galicia, Andalusia, and Catalonia concentrate the greatest access capacity

The analysis shows that the largest access capacity is concentrated in certain regions. Galicia has 1,666.2 MW (though with limitations in some points), Andalusia reaches 1,551.4 MW, and Catalonia totals 1,306.3 MW. By province, Lugo leads the ranking with 1,278.7 MW, followed by Barcelona with 1,113.9 MW.

In terms of relative saturation, Asturias is the region with the lowest level of substation saturation, at 26.1%, while the Canary Islands and the Balearic Islands show 37.9% and 38.6%, respectively. These figures contrast with the widespread scarcity across most of the territory.

A tool for strategic planning

This first access capacity map prepared by Opina 360 and Foro Industria y Energía provides a clear X-ray of Spain’s electrical grid and is a highly valuable tool for energy planning. Its aim is to provide companies, administrations, and sector players with transparent and updated information to guide decision-making in a context defined by the urgency of the energy transition.

The implications for industry are significant. As Isabel Núñez Rotta, Director of Institutional Relations at Foro Industria y Energía, explains:
“The saturation of the grid acts as a filter that increases uncertainty for industry and may redraw the industrial geography. Only areas close to underutilized nodes can host new projects, while saturated zones limit investment. It is no longer just about profitability or regulatory frameworks, but about the basic impossibility of guaranteeing the technical connection of a project, which could ultimately affect competitiveness and industrial development in Spain.”

The interactive map can be accessed at the following link.