Empa and TCS Demonstrate Quiet Advantage of Electric Cars During Urban Acceleration

Empa and TCS Demonstrate Quiet Advantage of Electric Cars During Urban Acceleration

(IN BRIEF) Empa and the Touring Club Switzerland partnered to measure noise differences between electric and combustion-engine vehicles using nine matched car pairs on a controlled 100 m track. Their analysis, employing custom sensor modules for repeatable driving tests, shows electric vehicles are substantially quieter when accelerating at low speeds—often more than 3 dB lower, effectively halving sound intensity. At constant urban speeds (30–60 km/h), however, noise levels converge due to dominant tire and road noise. Presented by TCS’s Sascha Grunder and Empa’s Reto Pieren, the findings will debut at Forum Acusticum in Málaga. Ongoing work through 2025 will deepen this research, followed by a 2026 study on the effects of tire and pavement variables, with publication slated for late 2026.

(PRESS RELEASE) DÜBENDORF, 24-Jun-2025 — /EuropaWire/ — Empa and Touring Club Switzerland (TCS) have teamed up for their inaugural collaborative study to compare the acoustic footprints of electric vehicles versus combustion-engine cars. Conducted on TCS’s 100-meter testing track in Stockental, the research evaluated nine matched pairs of vehicles—from the Peugeot e-208 and its petrol sibling to Volkswagen’s ID. Buzz electric van against the Multivan diesel—under both steady speeds and through acceleration maneuvers. Specially engineered sensor modules, affixed to each car, ensured that every driving profile was precisely replicated and objectively recorded.

Empa researchers developed special measurement modules for the tests, which were mounted on the vehicles. This allowed driving maneuvers to be precisely repeated and objectively evaluated. Photo: TCS

The research revealed that electric cars deliver a notably quieter experience when accelerating from low speeds, such as pulling away from traffic lights. In some head-to-head comparisons, electric vehicles measured over three decibels lower than their combustion counterparts—an acoustic intensity reduction equivalent to halving the perceived loudness. The disparity widened with stronger acceleration and lower vehicle speeds. However, once cruising between 30 km/h and 60 km/h—the speed range typical of urban traffic—no meaningful difference was detected, as tire and road noise overshadow engine sounds for both drive types.

“This joint effort breaks new ground by quantifying how much quieter electric vehicles can be in stop-start conditions,” stated Sascha Grunder, Head of Test & Technology at TCS. “Providing Empa’s acoustics lab with precise, real-world data has been invaluable.” Reto Pieren of Empa’s Noise Control Laboratory added, “Our findings affirm that e-mobility contributes significantly to reducing urban noise pollution. Working alongside TCS has been exceptionally productive.”

The full results will be showcased at the Forum Acusticum conference in Málaga. Building on this foundation, Empa and TCS aim to extend their investigation through the end of 2025, then examine how tire selection and road surface characteristics influence vehicle noise in a follow-up study slated for spring 2026, with outcomes expected by the close of next year.

Media Contacts:

Dr. Reto Pieren
Laboratory for Acoustics / Noise Control
Phone +41 58 765 60 31
reto.pieren@empa.ch

Manuel Martin
Communications Empa
Phone +41 58 765 44 54
redaktion@empa.ch

Marco Wölfli
Media spokesperson TCS
Phone +41 58 827 34 03
marco.woelfli@tcs.ch

SOURCE: EMPA