Research by Norway's Foundation for Scientific and Industrial Research (SINTEF) suggests significant potential for reducing both traffic noise and fuel consumption by combining low-rolling-resistance (EV) tires with specific kinds of road surfaces.

Testing carried out as part of a joint project between SINTEF and Gdansk Technical University, in Poland, involved recording a large volume of data relating to vehicle performance on different road surfaces and car tires, including those specially developed for electric cars. The aim was to discover combinations beneficial to reducing both traffic noise and CO2 emissions produced by conventional cars, as well as for extending the range of electric cars.

Traffic noise and fuel consumption could both be reduced with low-noise tires and the right kind of road surface. Image credit: SINTEF. Experiments were carried out on test tracks with a wide variety of road surfacing textures, as well as on ordinary public roads and in the laboratory. Road surfacing texture was "very important" in rolling resistance/noise and energy consumption, according to the researchers.

For four of the EV tire brands tested, rolling resistance was reduced by an average of 40%—providing a potential reduction in energy consumption of 12%-16% at constant speeds of 50 km/h in built-up areas and 4%-6% at 80 km/h, according to SINTEF. Further, the optimal combination of tire and surface provided a reduction in rolling noise on the order of 10 dB, which to the human ear represents a noise reduction of 50%.

“The measurements showed that an SMA8 [stone mastic asphalt with a maximum aggregate size of 8 mm] surface that was tested in Norway in the period 2012-2015—and which is known to provide minor levels of noise reduction—exhibits a difference in rolling resistance of 23% when comparing an EV tire manufactured by Continental (standard on an electric Volkswagen Golf) with a popular brand manufactured by Michelin," says acoustics researcher Truls Berge.

According to Berge, by demonstrating a reduction in both noise and energy consumption, the results raise the issue of a technology “transfer,” by which conventional cars could be fitted with tires developed for electric cars, combined with a reassessment of what road surfacing textures should be used in heavy traffic areas.