Federal Immission Control Act

Known in German as the Bundes-Immissionsschutzgesetz, or BImSchG, the Act dates from 15 March 1974. Its current consolidated text was published on 17 May 2013, and it was last amended in March 2026. It aims to protect people, animals, plants, soil, water, the atmosphere and the climate from harmful environmental effects, and to prevent them arising. Installations listed in its fourth implementing ordinance need a section 4 permit before they are built and run.

Backup power usually brings data centres under section 4. In June 2025 Brandenburg's environment agency logged a section 4 application for 24 emergency diesel engines and a life-safety generator at Trebbin, with up to 187 MW of thermal input, to serve data-centre building B1, and found that no full environmental impact assessment was required.

At Trebbin the permit and the Building work have come apart. The town said on 7 October 2026 that construction was under way on building permits while the operating permit under the Act sat with the state agency. Any conditions that permit carries will fall on part-built sites.