Spain has 386 grid nodes reserved for generation tenders and Just Transition Strategy (JTS) areas, representing 165,457 MW of access capacity currently unavailable for new electricity production model (MPE) projects, according to the latest monthly report from APPA Renovables, updated to 1 December 2025.
The data, sourced from the Spanish Ministry for the Ecological Transition and the Demographic Challenge (MITECO) and Red Eléctrica de España, highlights the scale of grid capacity set aside for future competitive access procedures.
Of the total restricted capacity, 176,116 MW corresponds to energy storage under the MPE framework, while 1,674 MW has been specifically allocated to self-consumption MPE projects. Although still modest in absolute terms, this figure points to a growing role for distributed and on-site generation within Spain’s electricity system.
Catalonia leads the ranking with 22,980 MW of MPE capacity unavailable, followed by Andalusia (25,338 MW) and Castile and León (20,635 MW). Other regions with significant volumes include the Valencian Community (13,816 MW), Galicia (12,066 MW), Madrid (11,723 MW) and Castilla-La Mancha (9,747 MW), underscoring both the geographic spread of grid constraints and the shared challenges around evacuation capacity.
At the other end of the spectrum, Navarre (2,064 MW), the Region of Murcia (1,954 MW) and La Rioja show lower absolute restrictions, although these limits continue to shape regional project development.
Reserved infrastructure for energy storage follows a similar pattern. Catalonia and Andalusia exceed 24 GW and 27 GW, respectively, while regions such as the Basque Country (17,288 MW) and Castile and León (21,436 MW) also show high levels of saturation.
In terms of self-consumption capacity, Castile and León stands out with 566 MW, followed by Aragon (202 MW) and the Valencian Community (211 MW), signalling stronger momentum for distributed generation in specific territories.
Since 2021, reserved nodes have become a strategic instrument within Spain’s electricity system under Royal Decree 1183/2020, which mandates that any grid capacity released at certain points must be allocated through competitive tendering processes. Nodes linked to the Just Transition Strategy are also kept in reserve to ensure the deployment of renewable energy projects in areas affected by the closure of thermal power plants or major industrial facilities, supporting economic and social reactivation.
The report also shows steady growth compared with previous months. The number of nodes reserved exclusively for demand-side access has reached 80, up five month-on-month. Andalusia leads this category with 19 nodes, followed by Castile and León (12), Aragon (10), Castilla-La Mancha (9) and Madrid (7). Regions such as Cantabria, La Rioja, Navarre and Asturias still have no demand-enabled nodes.
On the transmission network, total demand access applications exceeded 90,426 MW in December, across 122 requests. Energy storage dominates this segment with 37,371 MW, making it the second-largest category by volume and confirming unprecedented growth. This represents a new all-time high for storage projects that will consume electricity from the grid, either as standalone systems or hybridised with generation.
In addition, 25,597 MW corresponds to self-consumption installations connected at generation evacuation points, reflecting the consolidation of this model within Spain’s national power planning.
Overall, the figures point to mounting pressure on transmission grid connection points. The launch of new grid access tenders will be critical to relieve congestion and unlock further renewable energy, energy storage and grid integration capacity. As the institutional report notes, access capacity represents “the maximum active power that can be injected into the grid”, making every reserved megawatt at these nodes a strategic asset.
As Spain approaches a new wave of competitive access auctions, the current snapshot reveals a complex territorial landscape, with developers and investors closely watching a market increasingly shaped by the physical limits of the grid and the need for long-term planning to meet energy transition targets.
