Jan 18
How Electric Vehicles lead to the end of traffic noise pollution
Electric vehicles are too silent
Electric vehicles (EV) are silent. Particularly at lower speeds, under 30 Km/h. EVs are too quiet, according to regulators. EVs at low speeds beep alarms to warn pedestrians.
What at first glance may seem a defect of EVs can be ours. We got too used to tolerating a noise-polluted environment.
Our environment is just too loud
Noise pollution is so prevalent that it is easy to dismiss; it is just how things are. Such a mindset overlooks that noise pollution is much more than a nuisance.
Noise is a pollutant in the US Clean Air Act, and the European Union has a specific Environmental Noise Directive to address noise pollution.
Noise affects health
Noise pollution has serious health effects. In Western Europe, 1.6 million years of healthy life are lost yearly from noise pollution. The unhealthy effects of noise pollution include:
- Several cardiovascular diseases,
- Rising stress hormones,
- Cognitive impairments, including Alzheimer,
- Increased risk of anxiety and depression,
- Increased risk of diabetes and obesity,
- Besides the more known sleep disturbance and hearing loss.
Noise hurts animals too
Noise pollution also affects wildlife, something that the Covid lockdowns made more evident to researchers. It can also be particularly hard for pets, domestic, and captive animals at zoos in urban areas.
A meta-analysis review paper estimates that noise alone endangers the survival of over 100 animal species, both on land and sea, across amphibians, arthropods, birds, fish mammals, mollusks, and reptilians species.
Electric Vehicles can aid
Enter EVs with their lower noise. Traffic noise is one of the primary sources of noise pollution. Part of the problem with “silent” EVs is our desensitization to noise from overexposure. Were our environments less noisy, it would be much easier to notice the quieter EVs.
Traffic is a primary source of noise pollution. Noise differs between EVs and Internal Combustion Engine cars (ICE), with EVs emitting sound at a shorter band of frequencies.
The difference between EV and ICE noise benefits the former. A Japan study showed people in Japan preferred EV sound over ICE, which predisposes consumers towards EVs.
A study in China modeling the introduction of both light and heavy EVs concluded traffic noise decreases with a rising share of EVs on the street. The noise reduction is more significant for lighter EVs but relevant in both counts. In both cases, light and heavy EVs are about 5.5 dB(A) lower than ICE.
At lower speeds, up to 20 Km/h (EU, China, Japan) or 30 Km/h (USA), EVs are already silent enough to scare the regulators to require sound warnings. Above 35 Km/h, the tire rolling on the pavement becomes the primary noise source.
As such, studies tried combinations of tires and pavements to reduce noise on EVs and ICE cars. An EU-funded research project found a pavement design that achieved noise levels of 89.3 dB(A), below the EU’s limit of 93 dB(A).
EVs’ benefits also include substantial noise reduction, even in current conditions. In cities, with speed limits under 50 Km/h in most areas, EVs will quiet most neighborhoods. Adopting low-noise pavements can extend noise reduction to areas with allowed faster speeds.
