Why Brisbane’s busway fans were needed
In an enclosed busway, diesel exhaust cannot disperse into open air as it would on a street. Ventilation fans help dilute and remove pollutants, keeping the air moving through the tunnel. They are part of the infrastructure needed to operate a route used by vehicles that produce exhaust inside it.
What changes when the buses are electric
Battery-electric buses have no tailpipe, so they do not release diesel exhaust along the busway. That removes a major reason for running the exhaust-ventilation system. Brisbane can therefore retire those fans rather than keep using them to clear fumes that the buses no longer produce.
This does not mean an enclosed busway needs no ventilation for any purpose: airflow can still matter for heat, smoke, or other operational needs. The change is specifically that the system no longer has to manage routine bus exhaust in the same way.
The infrastructure benefit
Electric buses are noticeably quieter, but the less visible gain is that they can change what a busway must power and maintain. When the source of a pollutant disappears, equipment built to remove it may no longer be necessary. In Brisbane, the transition affects not just the vehicles on the route but also the fans that once had to run around them.
