Diesel generators emit high levels of NOx and particulate matter and can adversely affect local air quality. They may be proposed for life‑safety, business continuity (e.g. offices and data centres), or short‑term operating reserve (STOR) purposes.
All generators must be assessed within the Air Quality Neutral (AQN) calculation and, where relevant, dispersion modelling. An exemption will only be considered where the generator’s sole function is to supply essential life‑safety systems and where no cleaner alternative can meet the required emergency load.
Testing and maintenance are only exempt where a generator is installed solely for essential life‑safety purposes and must be strictly limited and controlled through a planning condition agreed with the Council. Generators installed for testing, standby, business continuity or STOR purposes are not exempt.