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Comment by adastra22 | Hacker News Reader

I'm not even sold on that interpretation either. There's a lot of externalities in the lithium battery industry that are being glossed over in most of those calculations. And gasoline can be made carbon-neutral through synthesis, using either solar or, ideally, waste heat from nuclear power to turn CO2 into gasoline. In that world a hybrid gets the best of both.

The main reason for wanting an all-electric future in my mind is the health benefits of not breathing in combustion byproducts every time you go outside. It's worth it for that.

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Lithium is not the future of batteries. As far as I know, there is no law of physics saying we won't someday have 2000Wh/kg metal-free flow batteries or something.

Lithium is just what we have now, and because business and politics is incremental(I'm not exactly a fan of that trait) we can't just say "Lets build all the charging infrastructure for cars that don't exist yet, stockpile electric cars with no batteries, and switch all at once as soon as we invent the better nonlithium tech to put in them".

Sometimes I wonder how much we could get done if people really did think like that though.

> not breathing in combustion byproducts every time you go outside

Also, engine noise. Noise pollution in cities can be maddening, and it's mainly car engines.

Yeah it was amazing for a few weeks during the height of the COVID lockdowns when all that freeway traffic went away and the smog cleared. Had no idea what we were missing out on.

Most road noise generated from a vehicle is from tires on the ground once you get above 18 mph. Modern mufflers are remarkably effective at silencing the engine.

IIRC at highway speeds the overall shape of the car moving through the air is also a significant noise generator, but I don't remember where I read that right now.

Source?

Not scientific, but literally just stand next to a road. A normal car driving at speed makes a “whoosh” noise, not a “vroom” noise.

Yeah I have no issues hearing an ICE vehicle coming from behind me when I'm on my bike. OTOH I have had many scared sudden encounters with an EV coming into my field of view.

Tyres on the road are white noise and barely noticeable. I don't know if they're louder than engines in terms of decibels as I've never measured either, but engines are definitely much more of a nuisance.

I can't find the exact studies anymore, but it's indirectly referenced by current regulations: https://www.regulations.gov/document/NHTSA-2011-0148-0075

> As required by the PSEA, (1) this rule proposes to establish FMVSS No.141, Minimum Sound Requirements for Hybrid and Electric Vehicles, which would require [quiet vehicles] to produce sounds meeting the requirements of this standard. This proposed standard applies to EVs and to those HVs that are capable of propulsion in any forward or reverse gear without the vehicle's ICE operating. The PSEA requires NHTSA to establish performance requirements for an alert sound that is recognizable as motor vehicle in operation that allows blind and other pedestrians to reasonably detect a nearby EV or HV operating below the crossover speed. The crossover speed is the speed at which tire noise, wind noise, and other factors eliminate the need for a separate alert sound.

>[...]

> This standard will ensure that blind, visually-impaired, and other pedestrians are able to detect and recognize nearby hybrid and electric vehicles by requiring that hybrid and electric vehicles emit sound that pedestrians will be able to hear in a range of ambient environments and contain acoustic signal content that pedestrians will recognize as being emitted from a vehicle. The proposed standard establishes minimum sound requirements for hybrid and electric vehicles when operating under 30 kilometers per hour (km/h) (18 mph), when the vehicle's starting system is activated but the vehicle is stationary, and when the vehicle is operating in reverse.

The EU has established a similar rule as well, though I think they only require up to 12mph. Wikipedia says there's a 2008 study that confirms it but it's source link is broken:

> A separate 2008 study from Western Michigan University found that hybrids and conventional vehicles are equally safe when travelling more than about 20 miles per hour (32 km/h), because tire and wind noise generate most of the audible cues at those speeds. Hybrid cars were also tested safe when moving off at traffic lights and it was found that under this condition they do not pose a risk to pedestrians. All Prius models used in the study engaged their internal combustion engines when accelerating from a standstill and produced enough noise to be detected.[13]

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

I have a hybrid, and it’s definitely noticeable when the engine is on. Maybe it’s a lack of space for a decent muffler?

Soon it will be the mandated noisemakers on EVs.

instead you get to breathe in that sweet, sweet tire dust, which hybrids and EVs tend to make more of because they're typically heavier than their ICE counterparts.

but until the electrical grid is moved to cleaner sources (including nuclear for baseload), it doesn't make much difference what you drive. with the current distribution of generation, we'd be mostly shifting the pollution from tailpipes to smokestacks (especially at the margin) rather than getting rid of it--coal emissions are many times worse than tailpipe emissions, not to mention the pollution from coal, oil & gas extraction.

and pollution is exactly what we should be worried about, not CO₂, which is the worst sort of distraction when trying to make sense of the environmental dangers we're creating (it muddies the waters to create uncertainty and inaction).

> coal emissions are many times worse than tailpipe emissions

The CO2 output of a coal powered EV and a gasoline car are roughly equivalent. If you add in the CO2 used when refining the gasoline and when transporting the fuel to gas stations, gasoline cars are about 50% worse.

> and pollution is exactly what we should be worried about, not CO₂,

For most pollutions, especially for PM2.5, locality is super important. Gasoline engines run in populated areas, power plants aren't.

again, CO₂ doesn't matter, despite the mediopolitical hysteria over it. it's a gas that life depends on and is well-adapted to. but pollution has been killing millions of people a year for at least a hundred years already and will continue to do so for the foreseeable future. generation and transportation account for the majority of that pollution.

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