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Comment by toxik | Hacker News Reader

Brake and tire dust absolutely are a problem, even if it’s inconvenient for you. Reducing fine particulate matter pollution is a major concern. That it translates onto railway is fairly unsurprising.

By the way, EVs reduce brake dust since they are basically braking magnetically a lot of the time.

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I believe that EVs on average are associated with higher particulate matter "emissions". Noowadays the majority of PM comes from the friction/erosion of tires on the road (as combustion soot gets filtered out due to regulations). Since EVs are typically much heavier due to their batteries, their tires give of more PM per km driven.

Much heavier is stretching things. An VW ID3 is about 200kg heavier than the identical sized petrol Golf.

A lot of EVs will be lighter than plenty of bigger petrol or diesel SUVs.

Most EVs will still be SUVs or crossovers, sadly. Even moreso than with current ICE vehicles.

In the US, I’d blame the IRA’s tax incentive structure which incentivizes the vehicles that GM (and Ford) find most profitable.

Regardless of regulation, the same market shift has occurred in Europe. As someone who prefers low and light vehicles I can lament this, but we can only blame ourselves. Wagon and sedan sales have plumetted. Even the king of affordable cars, the hatchback is suffering, with mainstays such as the Fiesta and Focus being discontinued.

Could you point to the specs you’re using please? I’m seeing 1800 for the ID.3 and around 1160 for the most recent petrol Golf.

Yes, increasing vehicle weight dramatically increases tire wear.

Large trucks generate a staggering amount of it, so much so that I wonder if it matters much how much an EV generates. I haven’t seen the figures for something like a Model Y though, so it’s hard to say.

Is it non linear? I wonder if reducing the maximum allowable load per wheel might be the fic and drastically lower road wear too.

How do cars filter combustion soot? Does the muffler have some sort of soot trap?

Modern cars minimize soot mostly by carefully controlling the combustion to produce a minimum of it. Any unburned fuel is an inefficiency, reducing gas mileage. Computer-controlled fuel injection helped advance this a lot (over carburetion).

So…cars don’t “filter soot”?

Most cars using a diesel engine are indeed fitted with a particulate filter nowadays. It is more or less necessary to meet environmental standards in most of the world. So at least some cars do.

Cars with modern fuel-injected engines produce very little particulate exhaust, and what little they do produce is burned in the catalytic converter.

What about gas cars that are a majority?

Poorly. Particulate filters have been common on passenger car diesels since the 80s.

So the vast majority of passenger vehicles (diesel is very small %)…don’t filter soot? Not sure what GP said was accurate then.

The vast majority do, certainly anything from the past decade or so does because it would be impossible to meet the pollution standards otherwise. The problem is what do you do with all the soot once you've collected it? You burn the soot or you toss the filter. Ford and Jaguar had to recall their diesels due to fire risk, and I think back in the 80s Mercedes did too.

> diesel is very small %

Depends of where you are. The share is very significant in Europe (it’s falling but still in the 30%-40% range).

Many trains, including diesel trains, use the motors as generators for braking. Electric trains might return the power to the grid, diesel ones can dump it into a large bank of resistors.

https://en.wikipedia.org/wiki/Dynamic_braking

To be clear, even diesel locomotives use electric motors to drive the wheels.

The diesel engines drive an on-board generator to make electricity.

This avoids the need for a transmission, which would have trouble delivering the torque needed to start the train from a standstill.

Intercity trains in Netherlands are EVs.

Is that net negative ? They are heavier so I'd imagine more tyre dust

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