Electric sound of the future

Brain City Berlin

What does an electric bus sound like? It hardly makes any noise at all, actually. That’s because the sound of the electric engine is barely audible against the general noise of traffic. Lukas Esser, a student at Berlin University of the Arts (UdK), has developed the new sound for Germany’s electric buses as part of a competition. It could soon also be heard in the Brain City Berlin.

The noise slowly increases in loudness, sounding a bit like a plane. Or like a lift going up. It gets particularly loud when the electric bus comes to a stop and starts again because these are particularly dangerous moments for road users such as pedestrians or cyclists. The quiet engine of the electric vehicle is barely audible without the sound effects. The aim of an artificial sound is therefore to give German electric buses a voice in road traffic in future – as a uniform audio industry standard throughout Germany and at the same time as a characteristic sound trademark “Made in Germany”. A Berlin student has created and developed the “electric bus sound of the future”: last year, 25-year old Lukas Esser, who studies “Art and Media” at Berlin University of the Arts (UdK Berlin), won a student competition organised by the Association of German Transport Companies (VDV) together with the Berlin FOAM Institute with his proposed sound. The objective set by the VDV was to develop, produce and introduce a uniform sound for all electric buses in Germany. And since the aim was to make the future sound of electric buses equally pleasant for all road users, various interest groups helped define the brief in advance of the competition, including passenger, transport and environmental associations, the federation for the visually impaired as well as federal and state transport ministries.

Pleasant audio warning system

The sound created by Lukas Esser is not only pleasant to hear, but also exciting thanks to its conceptual approach: it is based on piano recordings that he edited using software, as he explained to the Berlin Tagesspiegel. If the bus goes faster, the sound gets higher until it can hardly be heard. In the meantime, Lukas Esser’s sound has been professionally developed together with sound designers to become the standard sound for electric buses in Germany as requested by the industry association. The new sound was used on a bus for the first time in summer 2022. And at the end of March this year, the first manufacturers presented the new electric bus sound on their vehicles at the VDV-Electric Bus Conference and exhibition in Berlin's Estrel Hotel. According to an EU regulation, all electric buses must now have vehicle noise generators, so-called Acoustic Vehicle Alerting Systems (AVAS), which generate a warning sound at low speeds. The directive applies to all electric and hybrid vehicles sold in Europe with a type approval from September 2019 and to new vehicles from July 2021.

Unique, environmentally friendly and modern

If the new VDV sound based on Lukas Esser’s creation becomes the standard, it could also be heard everywhere in Berlin in a few years. Because there are already 156 electric buses on the streets of the Brain City today, and the entire BVB fleet of buses should be electric by 2030. This is an important step in reducing CO2 emissions and achieving Berlin’s climate goals. The city wants to be carbon-neutral by 2045.

According to Professor Sebastian Waschulewski, founder of the FOAM Institute, which specialises in sound design in urban areas, Lukas Esser’s sound creation is “first-class for the envisaged acoustic identity” of the electric bus. He claims it is unique, environmentally friendly and modern. The “electric bus sound of the future” is already attracting attention. And yet it is unobtrusive. Waschuleweski also stresses this point: “we call it the friendly neighbour.” (vdo)

The new electric bus sound (download)