More than 22 GW of battery storage projects have applied for grid connection in Spain. However, the bottleneck is not physical: peak demand sits 12% below the 2007 record of 45.4 GW. As we show in Red Eléctrica's recently released capacity maps, the grid has run out of contractual access rights, not physical space.

The Comisión Nacional de los Mercados y la Competencia (CNMC) published a proposed resolution on 20 February 2026 that would replace the binary model of firm access or denial with four types of flexible demand access. The consultation closes on 20 March 2026 and the final resolution may differ from the current draft.

Key takeaways

• The CNMC's proposed resolution (RDC/DE/003/25) would create four types of flexible demand access, replacing Spain's binary model of firm access or denial. The consultation closes on 20 March 2026 and the final text may differ from the current draft
• BESS in distribution must apply for flexible access. Firm demand permits are no longer available for storage
• Under the current proposal, Type 1 permits would be capped at three installations per limiting network element, creating a first-mover advantage at the most attractive nodes

​The revenue case for grid charging

The risk of not securing grid import access is material. Modo Energy's modelling shows that grid charging could add around 40% to annual BESS revenues in the near term, when ancillary service margins are still high, and availability and energy capture the most value. As more storage enters the market and ancillary revenues compress, the uplift narrows quickly.