Noise assessment of the Acoustic Vehicle Alerting System (AVAS)

Electromobility in car traffic in the area of conflict between noise protection and road safety

Electric drive technologies in motor vehicles result in a reduction in noise emissions from the drive train and exhaust system, especially at low speeds of up to approx. 30 km/h. At higher speeds, rolling noise from tyre-road contact generally dominates. At higher speeds, rolling noise from tyre-road contact generally dominates. While the positive effects on noise protection are undisputed, possible effects on road safety for non-motorised road users (on foot and by bike) as a result of the reduced vehicle noise are the subject of critical debate. In particular, blind and visually impaired road users are repeatedly cited as being at particular risk against the backdrop of increasing registration numbers of electric and hybrid electric cars (hereinafter: electric cars) if the noise source of the drive and exhaust tract, which is no longer present in electrically powered vehicles, is not adequately replaced. The Acoustic Vehicle Alerting System (AVAS), which has been mandatory for all new electric cars since July 2021, addresses this issue and is intended to improve the perceptibility of quiet vehicles at low speeds and thus road safety, especially for vulnerable road users. However, the potential of electrically powered vehicles to reduce noise emissions cannot be fully utilised with the additional noise.

On behalf of the Federal Environment Agency (FKZ 3718 54 100 0), the STUVA, together with the Institute of Automotive Engineering at the Technical University of Cologne and the former head of the Department of Immission Control at the Senate Department for the Environment in Berlin, Mr Bernd Lehming, investigated how the noise reduction potential of electrically powered vehicles can be exploited without compromising road safety.

The following research questions were addressed:

What are the legal framework and technical requirements in relation to AVAS? What is the accident risk for pedestrians and cyclists in view of the increasing number of registrations of electrically powered vehicles? Which groups of people are particularly at risk in connection with the perception of quiet motor vehicles? How does the acoustic perceptibility of electric cars differ from that of vehicles with combustion engines? What are the decisive factors for the acoustic perceptibility of vehicle exterior noise? Which different positions and perspectives determine the current discussion on AVAS? Which alternative measures are suitable to replace the current AVAS?

Stakeholders from various disciplines were involved in finding the results through surveys and a workshop. Answers to the above questions and recommendations for action can be found in the final report on the project (FKZ 3718 54 100 0), which is available free of charge via this link: www.umweltbundesamt.de/publikationen/laermtechnische-bewertung-des-acoustic-vehicle