this post was submitted on 24 Jun 2024
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Hot take: tire particulates are a conservative anti-EV talking point. "My V8 mustang weighs less than an EV, therefore its better on pollution than a EV because tire particulates". Totally disregarding the impact of tailpipe emissions.
One person I know claimed to have run calculations, and found that the tire dust alone was putting out more pollution than the tires and tailpipe of the average gas car. Idk where they got their numbers or how that could work out, since the average gas car in America is a large truck.
It could be true. Catalytic converters do a pretty good job of filtering out most pollutants. They also increase CO2 emissions in a variety of direct and indirect ways. Everything else is lower, though.
The way to make EV tires pollute less is to not chase 600+ mile range. Keep them around 300-400 miles, and use further battery improvements to reduce weight. There's no reason EVs have to be heavier forever. With better charging infrastructure, 400 miles is more than enough.
The way to fix everything else wrong with them is to not make cars the default mode of transportation.
Say it again louder for the folks in the back!
The "everything else" wrong with cars dwarfs the issue of pollution. Cars being the default mode of transportation is ultimately responsible for everything from obesity to the housing crisis!
That's a bit of a stretch, unfortunately. The energy density of batteries is nowhere close to that of gasoline - joule for joule, gasoline weighs about 100 times less than batteries. Also, a fuel tank big enough to give its vehicle a 400 mile range will get lighter over the course of the trip, as the liquid fuel gets converted into polluting gas and exhausted into the atmosphere - batteries don't get appreciably lighter as you discharge them.
Agree that 400 miles range with charging stations as ubiquitous as today's gas stations would help EV adoption. I do worry about the rollout of charging stations being slowed down by competition with expensive and fragile hydrogen tech (keep the hydrogen on boats and trains pls).
Frankly, I'm skeptical that hydrogen belongs anywhere.
Also, trains have no excuse to be anything other than electric! If you're spending the money building the track in the first place, it's really not that much extra cost to put up overheard wires too.
Hydrogen is probably going to get pushed out of every niche where it might be viable. Batteries tend to get better by 5-8% per year, and there's every reason to believe that will continue to be the case. Run that forward for another decade or so, and even things like heavy construction equipment and transpacific airplanes are viable on battery power.
It's a waste of time and money at this point.
Considering that the vast majority of hydrogen isn't even "green hydrogen" (produced from electrolysis) but rather "grey" or "blue" (produced from cracking hydrocarbons), I don't think it was anything more than a straight-up greenwashing scam in the first place. Even the niches where people claim hydrogen is suitable (long-haul trips without battery charging infrastructure) would be better off just burning the damn hydrocarbon as-is to begin with!
Even in the best-case scenario -- "green hydrogen" produced from electrolysis -- I think it would be better to immediately (at the point of production) combine it with CO~2~ pulled from the atmosphere to make synthetic gasoline and then handle that with our existing ICE vehicles and infrastructure. It's just so impractical to store hydrogen (since it's so small it leaks through everything, yet so low-density that it requires either extremely high pressures or cryogenic temperatures to fit enough of it in a reasonable amount of space) that it's simply not worth the effort.
Hardly a stretch. The comparison isn't to the power density of gas, but overall curb weight. EVs are roughly 10% heavier than an ICE equivalent. Batteries are the main reason for that (electric motors and the electronics to support them aren't that much). Batteries have also been improving Wh/kg by 5-8% per year. It only takes a few years of improvements to get there.
In fact, since the 10% number has been the case since around 2020 or so, the battery tech might already be there and we just need to get them into new models.
Edit: another way to think about it is what's been taken out of an ICE and replaced with something else. It's not just the engine, but an entire engine life support system. Coolant radiator, oil, transmission, gas tank, and ignition system. Possibly differentials, as well, depending on the electric drive train. It's replaced with motors (which don't weigh much for the power they output compared to ICEs), some electronics (which do need to be beefy to handle the current involved, but also don't weigh that much, relatively speaking), the battery (major source of weight), and the battery does usually need a cooling system, as well. So you don't need to compare it to the energy density of gas, but of all the stuff you replaced.