On a cycling thread, a discussion developed regarding the relative noise created by ICEs and EVs. As it was detracting from the OP it seemed a good idea to start a separate thread.
The question is, are cars which are propelled by a combustion engine as quiet as an electric vehicle as heard by an observer outside the vehicle.
Based on my totally unscientific experience my conclusion is that an EV is always quieter than a combustion engine vehicle. Full disclaimer, I have dodgy hearing so my ability to detect higher frequencies is diminished.
If I am sat in my house I can always tell if a passing car is ICE or EV. I live on a quiet road so the traffic use is very light but that means the sound is even more noticeable and intrusive than if there was constant traffic noise.
I can often tell who is driving past as well. There is the teenage girl in the Clio who is always late for her shift at the bakery and roars past at excessive speed. The farmer in his very badly maintained (probably illegal) Berlingo rattles past slowly checking his fields as he goes. The nurses swish past in their quiet new EVs. The Amazon delivery van arrives in an explosion of braking and gravel. The only time we know the post has been delivered being when the factrice, in her EV van, slams her door shut.
IMHO EVs must be quieter under normal circumstances.
I don’t think you need to express that as an opinion, because it’s the experience of everyone.
Isn’t it obviously true, because an electric motor works in a completely different way to an ICE? No little explosions of combustible, no valves opening and closing, etc (I’m beyond the limit of my knowledge here). There may be some super-quiet, beautifully engineered cars whose engines approach or reach the noise level of the average EV, but they’re so rare as not to matter.
In my experience, where a vehicle is accelerating hard, the internal combustion engine will be noticeable - the lass late for work in her Clio is an excellent example. But where a steady speed above 30mph/50kph is held on a level road then the difference will be imperceptible to most people.
The the 1100m route communale to our house is a single track metalled road. Some days there may not be any vehicle movements at all on the closest 500m or so.
Being rural our 'phone/fibre lines arrive via telegraph poles, which follow this road. The local birds of prey spend many hours sitting on the top of the poles, closely observing the surrounding fields for their next meal.
During the first 14 years of living here we had ICE vehicles & every time we drove along that road one or two buzzards or kestrels would take flight from their observation points, disturbed by the oncoming noise. The heron who likes to lurk by our neighbours large pond/small lake would also struggle up into the sky as we approached.
From the first day of having an EV back on 2018 it was very noticeable that the birds were no longer disturbed & instead just watched the car pass by with a look of feathery disdain. Changing the ICE van for an EV had the same effect a couple of years later.
Neither ICE vehicle was a noisy old banger.
Anecdote? Well, yes, but the lower noise level of the EVs is the only rational explanation for this change in bird behaviour.
My daughter and her husband recently looked at a house to buy. They were turned right off by the fact the Hellcat had to be garaged all the time and no revving and her big Jeep was not allowed to be parked on the drive as deemed a recreational vehicle and as for the Harley…The distance between the nearest neighbours was a good hundred yards or more but these Residential Housing Associations they have over there are the final hurdle in whether you can buy or not in their community. SIM remarked that there was not one EV parked on any drive or anywhere else though!
4 -5 dB quieter may not be much per vehicle but when you multiply it by the number of vehicles on the road within ear shot that could make a substantial difference.
If we are standing beside a road, as in the diagram, we expect a bit of traffic noise. It is when you are in your own home that external traffic noise becomes irritating.
I agree with you but apparently it is not as simple as that. On the other thread it was pointed out that, according to the Fletcher Munson law, some frequencies are decoded as louder than other frequencies by the human brain even if they are at the same dB level. I find this very interesting but hard to see how relevant it is (quantitatively) in the circumstances under discussion.
That is the beauty of discussions like this, you learn new stuff all the time.
It is not clear to me if wind and tyre noise “seems” louder than exhaust noise when stood at the side of the road. What is important to me is what I hear in my home, a restaurant or on a walk in the park. That is when the low frequencies generated by combustion engines are most intrusive.
Low frequencies having a lot of energy and long wave form are not as easily stopped like higher frequencies hence why buildings can shake when a Harley of HGV goes past.
The EVs, and the Hybrids when running electrically, are definitely quieter.
We have window flower boxes on the front of our house which has no front garden, so one is standing on the trottoir to dead-head the flowers. The street is very narrow and slopes gently downwards towards the bakery next door. Even when preoccupied with dead-heading I can always hear an ICE vehicle approaching and know to stay close to the wall out of the way.
The electric (silent assassins) are a different ketle of fish entirely. One just cannot hear them approaching as it is a 20kph zone. I have inadvertently stepped back into the path of one a couple of times but have fortunately avoided injury. I do so wish that they would be equipped with some sort of beeper when moving at less than 30kph so that us daft old blighters would know when one of them is approaching.
I must admit I thought it was now obligatory for EVs to make a noise when driving slowly so pedestrians etc can hear them coming…Our Renault Zoe emits what sounds like a rather weary groan below 30kph. On Renault’s website I found the following:-
