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Comment by CoastalCoder | Hacker News Reader

Just curious, what makes them particularly loud at highway speeds? And are they louder than similarly sized / weight ICE trucks?

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There aren't similarly sized/weight ICE trucks, the similar trucks are lighter because gasoline is more energy-dense than lithium ion batteries.

The H2 (the big 3-row one) weighs 6,400 lbs. The H3 (the 'small' 2-row version with seating for just under 5 adults) weighs 4,600 lbs. The HEV (ostensibly "Hummer Electric Vehicle", but obviously pronounced "Heavy") weighs 9,400 lbs and only seats 5.

All three are absurd tools to select for transporting a 160 lbs human between point A and point B.

If you change the numbers from 160lbs to 300lbs and 9,400lbs to 2,000lbs does it really seem any less absurd if you're looking at it strictly from a numbers point of view?

Yes? It's a factor of 6.6 instead of a factor of almost 60.

I can understand engineering constraints that say a vehicle with an energy source and controls and comfort and so on requires some multiplier that might not be less than 1, but 58x is a lot.

A 2000 pound theoretical car is 60x more weight than a bike that can also carry you. Looking strictly at numbers, a car doesn't make sense to transport a person in most cases. I'm not advocating for less cars, just that looking at it as a weight to payload issue doesn't make sense to begin with.

At highway speeds, tire and wind noise dominate over engine noise, even for ICE cars. That "roaring" sound you hear emanate from a highway is actually due to those two factors.

Tire noise in particular is affected by vehicle weight (I suspect--don't quote me--as a square of the weight). EVs are MUCH heavier that comparable ICE cars. The hummer EV weighs 9,000 lb (!). So they are extremely loud at highway speeds.

probably similar to a dually heavy duty truck. the sources of the sound is the enormous tires hitting the pavement with that much weight behind it

Judge for yourself: https://youtu.be/gulh7AxESyA?t=103

fwiw that's a vehicle with a modified exhaust (and not a particularly fast one to begin with)

So that's a truck EV... that has a Hemi V8 in it? I can see why you'd expect one to be loud.

(Jokes aside, most ICE trucks are not loud on the highway, unlike this one with a modified exhaust being demonstrated with wide open throttle.)

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