Noise pollution drop off

[FutureBoy]

I used to live somewhat close to a busy interstate and never really liked going outside because the sound from the traffic was loud enough to make it difficult to communicate. So my next residence we moved far from the interstate and it is soooo much quieter. I enjoy being outdoors sooooo much more.

This afternoon I went for a walk on a popular path around here that runs next to a river. Most of the walk has some traffic noise but its not bad. But in one section the path goes under a large interchange between the interstate and a state highway. The pathway is nice but the noise from the freeway is really loud.

I was thinking though that once everyone switches over to electric vehicles the noise should be reduced somewhat. The engine noise would drop out but there would still be tire and wind noise. Does anyone have a good estimate for how much of a noise difference that might be? When I'm driving my ICE vehicle around it seems like engine noise is louder than tire or wind noise. But it seems like that might be an illusion due to my sitting so close to the engine. When I was walking around today it seemed like the tire noise is the majority of what I was hearing.

Ideally the highway noises would have a significant drop and people living near the freeway would get a reprieve. I could imagine home prices being effected somewhat by this change.

 

[Crissa]

Yeah, no more clatter of engines.

-Crissa

 

[Cyberman]

I used to live somewhat close to a busy interstate and never really liked going outside because the sound from the traffic was loud enough to make it difficult to communicate. So my next residence we moved far from the interstate and it is soooo much quieter. I enjoy being outdoors sooooo much more.

This afternoon I went for a walk on a popular path around here that runs next to a river. Most of the walk has some traffic noise but its not bad. But in one section the path goes under a large interchange between the interstate and a state highway. The pathway is nice but the noise from the freeway is really loud.

I was thinking though that once everyone switches over to electric vehicles the noise should be reduced somewhat. The engine noise would drop out but there would still be tire and wind noise. Does anyone have a good estimate for how much of a noise difference that might be? When I'm driving my ICE vehicle around it seems like engine noise is louder than tire or wind noise. But it seems like that might be an illusion due to my sitting so close to the engine. When I was walking around today it seemed like the tire noise is the majority of what I was hearing.

Ideally the highway noises would have a significant drop and people living near the freeway would get a reprieve. I could imagine home prices being effected somewhat by this change.

I think the change will be so gradual as to be imperceptible, it's going to take a minute for us to all transition.

 

[ldjessee]

I have seen some reports claim 10 to 20 decibels, depending on the car to truck ratio, if your region requires inspections (here in the US states that require inspections usually have quieter cars because they have to have working exhaust systems), and if your country/region allows for 2 stroke motors.

 

[ajdelange]

I don't think you will notice much of a difference. Drive around a bit with a window open and pay attention to what you hear when another car passes you. Do this in town and on the freeway. Are you hearing mostly engine noise or wind/tire noise? Of course it depends on the vehicle but most modern ICE cars are pretty quiet with respect to engine noise. This is especially true with luxury cars. And of course there are still the idiots who pride themselves on how much polution, noise, particulate, NOx and CO2 their vehicles produce.

Obviously you will want to pay particular attention when you are being passed by a BEV. They are still pretty loud.

 

[larryboy31]

Lower frequency sounds "travel" a little better than higher pitched sounds. An EV would probably make a lot less low frequency noise than an ICE would make so at a reasonable distance from a highway the difference would be significant. The change to EVs will be gradual but as it happens the coal rollers and no muffler crowds will come under increasing pressure to conform to the norm.

 

[Ehninger1212]

I think we will hear a significant difference in low speed areas.. neighborhoods and city streets. But as AJ mentioned highways will likely maintain a pretty loud decibel level. Most of that noise is from wind and tires...

Although there is probably an argument somewhere in there about less wind noise due to more attention to improved aerodynamics? Also.. are LRR tires quieter?

 

[ajdelange]

The stock tires on the Teslas have sound absorbing material affixed to the inner side of the tread.

 

[ajdelange]

We should probably touch on the nature of the addition of sounds that are not "coherent". If we have a noise source such as an ICE vehicle's exhaust system that emits sound at X dBa and if that same vehicle produces the same amount of noise as road noise the total noise power is doubled but the perceived level is not 2*X dBA. It is "3 dB" more than X (i.e. X + 3 dBA) which represents a just perceptible increment to most humans under ordinary conditions. IT works the other way too. If engine noise is X dBA and road noise is also X dBA (total X + 3 dBA) and we find some way to completely eliminate the engine noise we have a total of X dBA and most people won't notice the reduction at all.

For us to notice an appreciable reduction engine noise has to be well dominant over road noise e.g. engine noise would have to be 10 times road noise. With modern ICE vehicles I don't think that to be the case which is why I don't think we will hear much reduction.

 

[Crissa]

Ahh, but that ignores the coherent tones and inconsistent sounds - a single background noise will be noticed less if it is either of these things. So the rush of the wind is less noticed than someone playing a clear tone; and someone playing a song with breaks and amplitude changes is more noticeable than just a long single note.

-Crissa