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In New York City, congestion pricing leads to marked drop in pollution

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Re: In New York City, congestion pricing leads to marked drop in pollution

#461

Post by panick21_ »

taeric wrote: post #391
bluGill wrote: post #389

Earlier quoted context omitted.

The vast majority of people I know have never lived where there was a transit system that would be useful for them. So of course they want other people to use it without planning on using it themselves. Give them a system that is worth using and they will use it (there will be a multi-year delay before they try/start using it though).

I've lived in Atlanta and Seattle. Both have perfectly workable transit. Even if Atlanta does seem to have gotten a bit worse over the years.

Seattle LRT has about the same usage as some german systems trams that are like 20x smaller. For a whole lot of the population that life around Atlanta and Seattle the public transport isn't workable.

Re: In New York City, congestion pricing leads to marked drop in pollution

#462

Post by margalabargala »

coryrc wrote: post #453
margalabargala wrote: post #451

Earlier quoted context omitted.

For those of us unclear why collecting air from passing cars to measure particulates is obviously flawed, could you elaborate? EVs unfortunately do increase tire particulate, as well. Fairly significantly. It's not obvious to me that the decrease in brake dust isn't made up by the increase in tire dust. The removal of the tailpipe emissions is really where EVs shine from a pollution standpoint. If you turn on your ca…

EV brake pads don't hardly wear down, so they obviously can't have nearly the same amount of brake dust, yet the "study" showed they did. I'm guessing there's brake dust on the ground being kicked up. > EVs unfortunately do increase tire particulate, Fairly significantly In the USA, mass of EV is not significantly different than the alternative choice. EVs do not have increased tire particulate. If in Europe extremel…

It's not just the fact that EVs are heavier than the non-EV version of the same car, it's also that the regenerative braking means that the tires are dissapating energy that otherwise would have gone to the brake pads or to air resistance. Tires wear way faster on an EV, their lifespan in miles is generally much shorter.

Re: In New York City, congestion pricing leads to marked drop in pollution

#463

Post by bob1029 »

shayief wrote: post #443
kjkjadksj wrote: post #370

Earlier quoted context omitted.

You can get this lack of brake pad use with an ice with a manual transmission as well if you engine brake.

the engine cannot brake to a complete stop, so break pads are always in use. At low RPMs, the engine is going to stall (manual) or switch to neutral (automatic).

Brake wear scales ~quadratically with vehicle speed. Applying them at 5mph vs 20mph is 16x less energy to burn off.

Re: In New York City, congestion pricing leads to marked drop in pollution

#464

Post by bob1029 »

l1tany11 wrote: post #382
t_tsonev wrote: post #340

Earlier quoted context omitted.

Specialized EV tires are also optimized for drag and noise, wear is just a factor. Anecdotally speaking I'm at over 80k km on a set of EV tires with at least 20k more to go. The issue has more to do with driving style and engine power than any other factors.

100%. Tire technology is a real thing. Tires have advanced a ton in the last 10 years. But driving style is the biggest thing. Some people can only get 10k miles out of a set of tires, while others with the same car and tires get over 40k. But they do care about tire wear a lot, they know the acceptable wear life for the class. A couple years ago I bought a set of Pirelli tires that were ~50% off because they were an…

Some tires are going to wear fast no matter what. I had some Pirelli PZero summer tires that I could never get more than 15k out of regardless of how I drove. The tire compound was very soft and sticky.

If you have something like really high performance tires, I recommend just using them. The grip is always there and you are always paying for it. As long as you aren't losing traction constantly, the difference is negligible in my experience.

Re: In New York City, congestion pricing leads to marked drop in pollution

#465

Post by duskdozer »

mikestew wrote: post #342
Spivak wrote: post #296

Earlier quoted context omitted.

I guess I should have said "a more inconvenient time" where owning an EV kinda revolves around your charging setup/schedule in a way that you don't have to think about with ICE cars. I know some people swear by them being more fun to drive but that's the last thing on my list of requirements for a car. I will say I think you're giving ICE cars a bad rap, my little Honda Fit that will be replaced by the EV is at 150k…

I guess I should have said "a more inconvenient time" where owning an EV kinda revolves around your charging setup/schedule in a way that you don't have to think about with ICE cars. I plug it in when I get home, and when I get in it again the "tank" is always full. I think about the EV a lot less than I do our ICE car, which seems to need gas at the most inconvenient times. You might have an argument for road trips,…

Doesn't constant charging to 100% wreck the battery longevity?

Re: In New York City, congestion pricing leads to marked drop in pollution

#466

Post by barnabee »

margalabargala wrote: post #462
coryrc wrote: post #453

Earlier quoted context omitted.

EV brake pads don't hardly wear down, so they obviously can't have nearly the same amount of brake dust, yet the "study" showed they did. I'm guessing there's brake dust on the ground being kicked up. > EVs unfortunately do increase tire particulate, Fairly significantly In the USA, mass of EV is not significantly different than the alternative choice. EVs do not have increased tire particulate. If in Europe extremel…

It's not just the fact that EVs are heavier than the non-EV version of the same car, it's also that the regenerative braking means that the tires are dissapating energy that otherwise would have gone to the brake pads or to air resistance. Tires wear way faster on an EV, their lifespan in miles is generally much shorter.

> it's also that the regenerative braking means that the tires are dissapating energy that otherwise would have gone to the brake pads or to air resistance

This does not seem correct...

- Air resistance slows the car without putting anything extra through the tyres (the friction is between car and air rather than between tyre and road)

- Regenerative braking channels energy into the battery, and also heat, that would otherwise be dissipated by heating and ablating the brake pads and discs, but regardless or whether it's brakes or the the motor acting as a dynamo that puts resistance on the rolling of the wheels, for a given amount of braking you will have the same forces between the tyres and the road and the same tyre wear.

So I'd expect it's only any additional weight that contributes to increase tyre particulates from electric care. Perhaps a tiny contribution from lower air resistance (on average at least) for electric cars, as there's often quite an effort to reduce the drag coefficient for range reasons, but I wouldn't expect this to be substantial as air resistance is not huge part of braking.

Re: In New York City, congestion pricing leads to marked drop in pollution

#467

Post by potato3732842 »

Aurornis wrote: post #125
lkbm wrote: post #2

> Particulates issued from tailpipes can aggravate asthma and heart disease and increase the risk of lung cancer and heart attack. Globally, they are a leading risk factor for premature death. Minor nitpick, but tailpipes aren't the primary source of emissions. The study is about PM2.5[0]. which will chiefly be tires and brake pads. Modern gasoline engines are relatively clean, outside of CO2, though diesel engines s…

> though diesel engines spit out a bunch of bad stuff. Exactly. The noxious tailpipe emissions in a city are usually from diesel trucks, small vehicles like motorcycles (small or absent catalytic converters), modified vehicles (catalytic converter removed or diesel reprogrammed to smoke), but not modern gasoline ICE vehicles. The love for diesel engines in many European countries was always confusing to me. PM2.5 is…

>The love for diesel engines in many European countries was always confusing to me.

It's expressly incentivized by their tax system.

Imagine the year is 1988 and you're some snooty jerk in Europe about to buy a Mercedes. Why on earth would you go with the noisy, smelly diesel option if not to save A TON of money over the life of the vehicle?

Re: In New York City, congestion pricing leads to marked drop in pollution

#468

Post by potato3732842 »

quasse wrote: post #269
cool_dude85 wrote: post #169

Earlier quoted context omitted.

Diesel is less fuel efficient than regular gasoline except when you measure by volume. It gets fewer miles per unit of energy in the fuel.

Can you source that? Diesel is only 13% more energy dense than gasoline [1] so the difference between the two fuels isn't huge. I suspect that modern (last five years) turbocharged gasoline engines are probably approaching diesel thermal efficiency, but I don't think that it's correct to say that they generally surpass it. The gasoline Ford EcoBoost is 33% thermally efficient while a BMW N47 turbo-diesel is 42% therm…

The fundamental difference in how the engine operates by throttling fuel only instead of air and fuel accounts for a large fuel economy savings

Re: In New York City, congestion pricing leads to marked drop in pollution

#469

Post by SR2Z »

SoftTalker wrote: post #189
Aurornis wrote: post #125

Earlier quoted context omitted.

> though diesel engines spit out a bunch of bad stuff. Exactly. The noxious tailpipe emissions in a city are usually from diesel trucks, small vehicles like motorcycles (small or absent catalytic converters), modified vehicles (catalytic converter removed or diesel reprogrammed to smoke), but not modern gasoline ICE vehicles. The love for diesel engines in many European countries was always confusing to me. PM2.5 is…

Modern diesel engines with DPF and DEF are pretty clean from a particulate and NOx standpoint. Of course there are still older diesels on the road, mainly buses and trucks. In the USA, diesel is so unpopular as a passenger car engine that it's not even worth worrying about.

I don't think you can just say diesel is less popular in the US without bringing up the emissions scandals. It genuinely seems to me like companies can't deliver clean emissions and efficiency gains at the same time for it.

Re: In New York City, congestion pricing leads to marked drop in pollution

#470

Post by potato3732842 »

efaref wrote: post #154
Aurornis wrote: post #125

Earlier quoted context omitted.

> though diesel engines spit out a bunch of bad stuff. Exactly. The noxious tailpipe emissions in a city are usually from diesel trucks, small vehicles like motorcycles (small or absent catalytic converters), modified vehicles (catalytic converter removed or diesel reprogrammed to smoke), but not modern gasoline ICE vehicles. The love for diesel engines in many European countries was always confusing to me. PM2.5 is…

The love for diesel came from a catastrophic misunderstanding and the resulting belief that CO2 must be reduced at all costs . Diesel engines of the past produced slightly less CO2 per km than petrol engines in exchange for much worse overall emissions. The fact that they were slightly more efficient in terms of fuel consumption helped with the sales pitch, too.

Nobody was even thinking about CO2 when the policies that got Europe where they are were enacted.

Europe began embracing diesels 40yr ago when they were noisy and stinky and they did it because they taxed the crap out of fuel so people rightfully prioritized buying vehicles that got better fuel economy.

Giving a crap about CO2 is a recent thing.

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