Environmental Impact Assessment Rules for BESS Projects
The APA has clarified when battery energy storage systems (BESS) must undergo an Environmental Impact Assessment.
The Portuguese Environment Agency (APA) has clarified how the Environmental Impact Assessment (AIA) regime applies to Battery Energy Storage System (BESS) projects. Under Decree-Law No. 151-B/2013, these projects are not expressly listed in the annexes, so whether an AIA is required depends on location, size and a case-by-case assessment by the APA.
Assessment criteria
Location in sensitive areas, project size and BESS-specific risks — such as fire, release of hazardous substances or cumulative risk with other energy infrastructure — can trigger the AIA requirement. Joint Order No. 2 (APA and DGEG, 31 July 2025) further clarified how co-located storage in already-licensed renewable projects is treated.
- Not exceeding 50 MW / 200 MWh in common areas, or 20 MW / 80 MWh in sensitive areas
- Complying with the environmental conditions of the original DIA or DCAPE
- Completing a post-assessment phase and keeping a 5-metre setback