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Comment by fnordpiglet | Hacker News Reader

What this tells me is that the internal combustion engine is a bad idea everywhere but especially in a dense urban core.

People like both the dense urban core and the suburb single family home life style. They are very different modes of life. A lot of Europeans I know really like one or the other because they don’t really get them back home.

The solution to road noise doesn’t have to be a dramatic rezoning and a reversion to Europe everywhere. It could be to make cars and trucks quieter.

(N.b., I’m specifically not addressing SFH and housing shortages in this, hopefully that’s for a different thread)

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I also thought EVs would be quieter but as they became more common in my street I noticed they’re only a little quieter than internal combustion cars from the moment they reach a certain speed (say 30km/h).

Most of the noise comes from the tire friction and aerodynamics.

Urban core traffic is slow moving and dominated by engine noise. In fact it’s generally dominated by public transit noise - massive double length buses, of services - garbage trucks. Tire noise is more an issue for folks living next to high traffic thru routes.

A city on its own generally has the power to change zoning and land use laws. There are limitations (some states give cities more or less power here) but generally cities do have the ability to make changes that would reduce noise and improve quality of life for their residents.

On the other hand, cities do not have the ability to redesign cars. A city can’t just choose to invent a quieter car!

I would love it if we can engineer cars and trucks to be quieter; I think though that a more feasible path for any city is to work on zoning and land use changes.

> What this tells me is that the internal combustion engine is a bad idea everywhere but especially in a dense urban core.

Engine noise only dominates up to roughly 20mph, at higher speeds the tire noise is the dominating component until roughly 100mph where wind becomes the dominant.

So this:

> The solution to road noise doesn’t have to be a dramatic rezoning and a reversion to Europe everywhere. It could be to make cars and trucks quieter.

Would mean both switching to electric cars and reducing speeds significantly to less than 20mph.

This is about the urban core. Speed in the urban core in every US city I know is 20.

I don’t think that average speed is the relevant measure here. Top speeds would still be noisy.

But even at average speed you’d see no noise reduction from electric cars since 20mph is the point where tires are as loud as the engine. So the average would need to go down.

Tires make more noise than modern engines. A Tesla will be just as loud, if not more, than a small engine compact ICE.

Cars aren't loud because of the engines. A Tesla driving by isn't much louder than an equivalent ICE-powered alternative. A lot of the noise is the air resistance and the tyres.

Not in the urban core. Speeds are low in the urban core. Further, in my personal experience, busses make up most of the egregious noise with their extraordinarily loud ICEs. Some cities like SF have electric busses and they’re materially quieter than say NYC or seattle which have behemoth ICE noise death machines.

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