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Comment by MengerSponge | Hacker News Reader

The secondary costs of running a diesel fleet are also huge! Diesel motors generate a substantial amount of fine particulate that is unhealthy for anybody, and particularly unhealthy for children.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC121970/

Even if an electric fleet is the same cost, changing over would save tons of money and alleviate tons of suffering. It's the right thing to do for any ethical reason you can consider.

Unless, I suppose, you're intent on making the poor suffer. Diesel buses are very cost-effective at accomplishing that.

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Even in terms of primary cost, diesel buses are expensive to maintain. My FIL was a mechanic for the local school district for 15 years, so I got a little insight into that aspect of the district. Our medium sized school district, 4 big high schools and all the feeder schools for them, employs around 6 full time mechanics plus their manager with all the equipment and the facility to work on the buses year round plus parts etc. It's not difficult to imagine that cost alone adds at least $1 million to our district's budget annually. In addition they have to have some percentage of extra buses because they are constantly rotating buses out for maintenance. They also have to have at least one extra bus and driver on standby every day because diesel buses breakdown regularly during a route and they have to go out with a second bus and pick up the kids and finish the route.

So if a district can outsource part of that maintenance cost, and electric buses prove to be lower maintenance and more reliable that their diesel counterparts, there are significant savings to be had for the school districts.

> diesel buses breakdown regularly

In comparison to what? Diesel engines in commercial vehicles are extremely reliable. It certainly could be possible for an electric bus to be more reliable, they certainly have less points of mechanical wear. However, there are a lot of power electronics going into charging their batteries and delivering the battery power to the motors.

He probably lived through the "Maxfarce" era in which the Navistar MaxForce diesels that everyone and their brother ran proved to be less reliable than the International 7.3 IDIs they were replacing. To be clear, they weren't unreliable, they just had a tough act to follow.

The diesel engines in the Thomas busses my school district had in the 90s would like to have a word with you. Those fuckers were always breaking down. lol.

Plus they smelled like death and produced gross amounts of black smoke.

Cummins diesels, Toyota diesels, Kubota diesels, Yanmar diesels Yes definitely.

US Detroit diesels? lol no.

DDC has been "detroit" in name only since the late '80s. First owned by Penske, then Daimler. The Series 60 and newer are perfectly acceptable diesels.

Most parts that break on a car are common to electric or engines. Suspension, brake fluid (the brakes might last longer but the fluid should be replaced every few years), tires, doors, seats.

> Most parts that break on a car are common to electric or engines. Suspension, brake fluid (the brakes might last longer but the fluid should be replaced every few years), tires, doors, seats.

It is true that a lot of parts are in common. But there are a lot of moving parts, susceptible to failure in an ICE not in electric.

I spent a lot of money recently fixing an oil leak and replacing the cam belt on my ICE. Routine maintenance (the leak specifically was not routine but leaks generally are).

My next car will be electric, I hope.

Sure, but I just spent a lot of money on my car fixing non engine related problems. Most of the moving parts in an engine are well lubricated and thus don't fail very often. The real expensive failure on any car is when road salt rusts the body away.

"Most of the moving parts in an engine are well lubricated and thus don't fail very often."

For all our family cars over last 30 years, 90% of repair cost was engine. Those oarts are under temperature, pressure and massive friction.

Can you name them? The engine is lubricated that well just because it gets the most wear and tear. The lubrication just tries to slow it down as much as possible. That's the reason why changing oil and filter is the first and foremost maintenance item on the list.

Shocks, struts and other suspension parts. After 10 years and 170k miles they were well worn.. these get a lot of wear and are not well lubricated,if only because unlike an engine they cannot be sealed.

Windshield was cracked.

Something in the TPMS was messed up.

Brake fluid change (another thing that few people do but should be done)

I didn't pay to fix the blind spot warning system, I want to but the repair costs is more than the car is worth.

Diesels, in general, are notoriously unreliable.

The only very selective myth I still hear repeated is that diesel engines are more durable now than they were, which isn’t saying much, and skirts around just how much else can and regularly does go wrong with a diesel-powered vehicle.

Flywheel clutches are an expensive nightmare, and the vibration destroys manifolds, cams and exhausts in short order.

That’s only for the dirtiest diesels that aren’t properly using DPFs or AdBlue (which if you’re seriously considering running school buses in 2022 and not using these, you’re a disgrace). Both of these fail regularly and cost a small fortune to replace.

There’s an entire underground industry dedicated to removing the particulate filters from Diesels to improve fuel economy and reliability (because I guess some people just hate kids, who knows?).

Electric vehicles have been around for well over a decade now, the data is back on them, and on the whole they are astonishingly reliable compared to the ICE vehicles they are replacing. There’s a lot of cables, sure, but they’re flexible and aren’t inherently moving parts.

If Diesel engines are so unreliable why are they used in practically every heavy goods vehicle, bus, tractor, plant equipment, ship and backup electric generator in operation today?

Torque.

I thought electric had better torque, ie acceleration...?

Which, incidentally, is also something electric motors are far superior at (flat curve...).

Not true. There are diesel engines that have warranties up to half a million miles.

The old ones "run on physics"

There absolutely are high warranty Diesel engines. That doesn't mean they'll last that long - a lot of those warranties are subsidised by servicing.

Even with that said (and as detailed above) there are so many other parts to a modern Diesel-powered vehicle that can and regularly do go wrong that they get a pass for because it's not in the engine block. I do wonder if this is because people just assume the vehicles are otherwise identical beyond the engine.

I agree, sorry to be tangential, but school buses even have a whole community around converting them into rvs/homes, skoolies. The advice thrown around most often within this community trends toward picking diesel over gas, because diesel ones are very reliable when maintained. I always read it's better to get a pre-2004 diesel bus, because they have simpler, more mechanical parts. Diesel engines are really hyped among skoolie enthusiasts, though of course that is not to say that in e.g. fb groups, you don't hear horror stories of people stranded with a broke-down rig, it's usually lack of maintenance though. When maintained, they do last well past when school districts retire them--maybe survivorship bias, the ones that lasted to the end were more likely to keep lasting. My boyfriend has one such bus that was made the same year he was born (1989) and it took us on a 10-state roadtrip and was our home for over a year.

Exactly. Take construction or military machinery as example : they are all running diesel. Who says that's not reliable? Probably after clocking more than 200.000 km and without maintenance. Motors on good shape and we'll maintained don't break down regularly

My daughter takes an electric bluebird to school. It has broken down numerous times this year, it has even stopped mid-route due to low battery (no idea who's to blame for that). Nevertheless it's nice to see progress and things will get better.

> They also have to have at least one extra bus and driver on standby every day because diesel buses breakdown regularly during a route and they have to go out with a second bus and pick up the kids and finish the route.

I distinctly remember being one of those kids that would have to be picked up in another bus every once in awhile. This was before cell phones, so the bus driver had to walk to the nearest house (this was out in the country) and ask to use the phone. I think we had a problem bus for a few months where this happened fairly regularly until they swapped it out for a different one.

One time a passing vehicle kicked up a rock that took out the windshield. Nobody was seriously injured, but there was a fair bit of broken glass.

The buses in my small town all had radios (and quite a bit of chatter between drivers, as I recall). Were you in a district with very long distances or geography where that wouldn’t have been feasible?

My bus route wound over and between a couple of hills, so a radio might not have worked.

My father was a business manager for a few different school corporations. In at least one of them, the busses were all used - none were purchased new. It just wasn't worth it, and much cheaper to simply have an extra bus. You needed the mechanics regardless just to maintain them. You needed an extra driver anyway as well because people get sick. These aren't really the costs you are leading folks to believe they are, but part of overall cost savings.

One of the most wasteful (and expensive) things about school busses is that they are only used for school, which means they sit idle for much of the day. My father tried to work with at least one city to combine city busses with school busses - but state law (Indiana) forbid this since school busses were required by law to be the classic yellow with black markings.

I'll also add that outsourcing isn't without challenges, and the employees are often worse off. (I don't remember as many specifics right now: My father, who died 9 or 10 years ago, generally worked with custodial and cafeteria outsourcing.)

> I'll also add that outsourcing isn't without challenges, and the employees are often worse off. (I don't remember as many specifics right now: My father, who died 9 or 10 years ago, generally worked with custodial and cafeteria outsourcing.)

(In the following post I use "you" rhetorically, not talking about Broken_Hippo directly.)

Yeah. The body rental place makes it look like the killerest deal imaginable, like you get all the benefits of having human workers, minus actually having to deal with any human problems. No unions or strikes, if the body rental you're using gets organized it dies without the collateral damage to the renter, you just switch outsourcing unit. And there's tons of other human problems, and those human problems require other humans's help. They ought to get real, people are expensive, life is expensive, if something is more expensive than life we replace it with life.

There is this deal you can get where you pay about half market wages, almost exactly half, and there's no unionization or anything. Just have to worry about emigration. Called slavery, these days people focus on the whipping and the coercion, they forget if you're a slave your master will be disgustingly cheap with the things you need he must provide for you, because he knows it's literally painful to ask.

If you want something cheap and rather your money ends up spent on electricity than food, like who cares a joule's a joule, go, go and fire 100% of your workers and replace them all with machines. Sure to make a lot of money!

What will you spend it on, alternating current or direct current? What voltage are you compatible with?

>One of the most wasteful (and expensive) things about school busses is that they are only used for school, which means they sit idle for much of the day.

In my country's capital there is a plan of using a fleet of school mini-buses (as "taking kids to school" is among the top reasons why people say they still use a car for their daily commute), but also of putting these to work outside the narrow band of school start/end in other uses: taking old people to their doctors appointments, and commercial on-demand uberpool type transport.

California's greatly surpasseed the misery of their old diesel fleets. In a bid to "reduce carbon emissions" (really: cut budgets in the way that screwed over parents as much as possible), they simply eliminated most school busses.

Then, the state government claimed this reduced carbon emissions, ignoring the externalities associated with doubling most parents' commutes for 18+ years.

Stating the obvious here, but eliminating school buses and thus making people have to drive their kids to school would INCREASE carbon emissions. So the statement is both factually incorrect and a shameless attempt at misdirection.

"Misleading and factually incorrect": the foundation of all public policy in CA.

Do school districts still use diesel? CNG seems pretty popular these days.

Likely the CNG buses are purchased by wealthy districts and the less well off districts purchase the used diesel buses at a discount.

I'm in high school in the USA and am on multiple interscholastic sports teams, and am also interested in transportation. I have yet to see a single CNG school bus

For city buses. Schools are mostly diesel from what I've seen. You need special infrastructure to fill CNG, which limits trips.

> Diesel motors generate a substantial amount of fine particulate that is unhealthy for anybody, and particularly unhealthy for children.

This is one of the biggest issues with US' private healthcare system.

The U.S. government just doesn't feel that direct "cost" in the same way countries that have to pay to fix the health of their citizens do. This is why you see a lot of other countries put higher taxes on sugar, gasoline, diesel, etc. Because they see a direct correlation between the consumption of those things and them having to invest more in their national healthcare system out of their tax money.

Meanwhile, in the US, since it's the citizens that pay out of pocket, that money still goes into the economy, so it's kind of all the same to the government whether or not they get sick or not. They may notice some correlation in the long-term, but the negative effects of these things are not nearly as urgent to the government.

Canadian has free healthcare and still has diesel public/school buses

Very true and also the reason for the exploding costs of the education system people complain about. In countries where universities run on public budgets you won't see exploding administrations and degree inflation because the state has a direct incentive to keep costs low rather than handing out loans that go to private institutions.

Was honestly surprised when I saw that the rate of university graduation in the US is twice as high as it is here in Germany.

I guess if you're a year/two into a course in America you'd probably have $20,000 in debt to pay. If you have to pay it without graduating then you'd probably think you'd wasted the money - so you'd be likely to finish the degree to make sure you got "something" out of it.

By contrast here in Finland education is free, so it's a lot easier for people to start courses, and if it didn't suit then drop out. Or move cities, and get a job.

Where education is free I'd expect both more people to sign up to it, but also more people to drop out. Or take 10+ years to eventually get their degree whilst continuing to work.

I really doubt this causation, for a few reasons.

1. Everyone gets sick and dies. Dying a bit earlier from diesel probably doesn't cost more than whatever you would have died from later.

2. These other countries also have government funded pension system. If people live longer that's an added expense! If you do the cynical math, government finances are best if people die of something cheap soon after they retire.

Consider that, even for two people who die at the same age, the one who is sick for many years before dying probably incurs more healthcare costs.

Nope, about 1/3 of Americans have Medicaid or Medicare. At least 6% of all gdp is government dollars in healthcare, probably more.

The US spends about as much as peer nations on healthcare through taxes. Then it spends that much again in private expenses. In return it gets poorer health outcomes.

https://www.healthsystemtracker.org/chart-collection/health-...

https://www.statista.com/statistics/237043/us-health-care-sp...

Huh? Most of Europe has socialized medicine and they have a ton more diesels and thus air pollution than the US.

Yes, that was a mistake. Diesel was promoted as lower C02 than petrol engines, before the problems with particulates were well known. (1)

This is of course changing now. (2)

As noted in the second link, a factor is the "Volkswagen emissions scandal", AKA "Dieselgate" (3)

1) https://www.bbc.co.uk/news/uk-politics-41985715

2) https://www.autoexpress.co.uk/car-news/consumer-news/98747/d...

3) https://en.wikipedia.org/wiki/Volkswagen_emissions_scandal

Lots of nations have public health-care and millions of diesel motors.

This is simply false.

https://www.cbo.gov/publication/56571

> Federal Subsidies. In CBO and JCT’s projections, net federal subsidies (that is, the cost of all the subsidies minus the taxes and penalties) in 2021 for insured people are $920 billion, or 4.4 percent of gross domestic product (GDP).

The US federal government (that is, excluding state and county governments, which also spend money on this) spends 920 billion dollars a year on health insurance and care. This also excludes the VA system (~200 billion), which does cover dependents. So that's 1.1 trillion per year by the federal government alone. To take California for an example, you can add another 100 billion in state spending on Medi-Cal. It's also not uncommon for counties and cities to operate and run their own hospital systems.

(Disclaimer: have driven pure electric for going on 7.5 years)

It may be more complex: electricity generation is very dirty in some regions, such as where coal is burned.

Is it more dirty than diesel emissions? I have no idea, but old diesels were nasty.

It's much cleaner, even after accounting for losses in electricity transport and storage. Power plants are just much more efficient than mobile internal combustion engines.

Let's not forget the diesel emissions cheating scandal. Diesel engines are so amazingly difficult deal with from an emissions perspective that it's basically impossible to build one with an emissions system that doesn't require constant maintenance (filters, additives).

Diesel emissions requirements for commercial vehicles are much more lenient for this reason.

Yes because the coal burning is done at a central location with fairly advanced technology to capture dirty hydrocarbons. The tailpipe is spreading soot all over.

No, it is not more dirty than diesel emissions. Coal plants are stationary, so they can install huge scrubbing apparatus. Diesels have to drag whatever cleanup mechanism they have installed with them, which is inherently limiting.

Also, those coal plants aren't parked outside primary schools idling, and schoolkids aren't spending hours sitting around their smokestacks.

Don't get me wrong: Coal is dirty as sin and radioactive as hell. Coal delenda est.

Engineering Explained did the math: https://www.youtube.com/watch?v=6RhtiPefVzM

Spoiler: Well-to-wheels, BEV cars are better than the best gas cars (top end prius) even if the source electricity is 100% coal.

The best is still not driving, but it's a step in the right direction.

Not driving would mean smaller schools closer to home, and infrastructure that allows kids to ride their bike to school. It's completely doable, but it does require people to care about more than just cars.

It would significantly expand taxes, and that nearly always faces stiff opposition with voters. Especially when it is an open-ended increase.

> It would significantly expand taxes

How exactly? Do you have any examples? Also, have you ever seen the price of car infrastructure? I would be willing to bet that denser walkable urban infrastructure projects are waaaaay cheaper than building and maintaining sprawling road, sewage, and power transmission networks. Sprawl is seriously draining the finances of many small cities and towns in the US. There's a whole book about it: https://www.google.com/search?q=strong+towns

You could also just watch this smug video https://youtu.be/7IsMeKl-Sv0

Yeah, but it's not terribly likely that you could stop maintaining the sprawl, because it's already there. Certainly not quickly.

Yeah they are going to raise taxes to pay for it because that's all they can do. Which is the opposite of what OP said

The only way you could sell it as an overall less expensive option would be with really elaborate studies that could convincingly tie the transportation effects to the design of the school system.

But, when it comes to schools, fewer buildings means lower costs. We've been suffering this for years, there aren't anywhere near as many schools in my district as there were 30 or 40 years ago, even as the number of students go up. It's less expensive to consolidate the schools into a fewer number of locations and increase the capacity of the remaining locations.

Ergo, going the other direction and creating more, smaller schools (each with their own infrastructure, custodians, some level of administration, etc) is going to require taxpayers to foot the bill. And not like a levy that only lasts for X years, but on an ongoing basis. Where I live (Oregon) there is massive resistance to new taxes. I do not think we are unique in that regard.

America is actively against letting your kid out of your sight, with the fear of bad actors perpetuated by primetime news channels being the driving factor. The advent of only needing to part with your child when you drop them off at school, or watch them get on the bus, provides a framework for chain-of-custody and accountability if anything were to happen to the child. Unless you still allow car access for the parents worried about this, simply putting more schools within a mile or two of homes isn't going to work without parents being on board.

A school being a mile away with safe sidewalk tend to convince people the kid can go alone sooner.

There's also the fact that coal power plants tend to be pretty far from heavily populated areas. Even if the US power grid were 100% coal (which it is not) this would still be a win as far as cleaner air goes for a significant portion of the population. There's a big difference between a coal burning power plant's emissions 50 miles away and a school bus idling right outside your house in terms of air quality. That's not even counting the air scrubbers and particulate capturing systems many coal power plants are required to have. The bottom line is the exhaust coming out of a coal burning power plant is much cleaner than even a brand new diesel school bus, let alone all the older buses still in service.

The biggest source of particulate in my neighborhood as in most is recreational wood fires, where they allowed. The diesel schoolbus is nothing by comparison. Actually the fires are not allowed but people do it anyway and you need a drone to find them.

Plus coal is more expensive by LCOE than wind and solar, and has been for several years.

That means electric companies are losing money running coal plants.

They are racing to replace them with wind and solar and natural gas turbine, with the gas turbine slater for replacement with storage once that is cheap enough.

Finally, with EVs and the electric grid, the power can be phased out centrally. Even if coal is used RIGHT NOW, once new power generation is available it is a seamless switchover for EVs.

If in the long term some dirt cheap thorium reactor supplants solar and wind, EVs don't care where the electrons come from.

Plus home solar, EVs doubling as home energy backup/storage, less components in the EV require less manufacturing, safer skateboard design, more internal space, lower center of gravity, regen breaking.

Although the ideal transition is a 100 mile LFP PHEV for the next ten years. No range anxiety, 90% + of daily and weekend driving is all electric, maximizes use of current manufacturing capacity of batteries, regen breaking efficiency.

Ten years ago (,ten years after the first Prius) we should have required all consumer passenger vehicles to be PHEV in a phased in manner.

It's still not too late to do that.

This video is actually a great example of how smart people can fool themselves.

The sources he uses for breakeven time (DOE) assumes 24.3 mpg [1] for the average regular car, but people don't drive average cars they drive specific cars.

If you take the DOE assumptions and approach this from the other end, CO2 pollution by mpg, then you find an ICE car getting approx 30 mpg or more is less polluting per mile driven than an EV powered entirely by coal, and one getting >45 mpg is less polluting than an EV powered by natural gas. This does not include the battery at all, which makes sense as it is an independent consideration.

This is a more honest way to present the information so individuals can make informed decisions for themselves among potential car purchases and so that people aren't fooled into thinking that all EVs are less polluting in all circumstances.

1 - https://afdc.energy.gov/vehicles/electric_emissions_sources....

How is doing a calculation based on assuming electricity sourced 100% from coal or NG help develop an informed decision? US electricity is roughly 40% carbon free, 40% natural gas and 20% coal - wouldn’t it be more honest to use this mix in your calculation? And that’s ignoring particulates and NOx.

Coal is used to establish a lower bound.

And maybe as the type of generation used for the marginal difference in energy required. If your country generates 90% of its electricity from hydroelectric and 10% from coal, you might still use coal for the comparison because hydroelectric power would be slow to add and the extra electricity for EVs would have to provided by coal

This is an important point. I live in Illinois which is over 60% carbonless mainly through aging nuclear investments. It would be naively optimistic to suggest that marginal demand will be only 40% fossil fuel since the nuclear will not be replaced.

Assuming that it's more likely that marginal demand will be met by coal than by renewables makes no sense to me.

Coal is rapidly been retired as a source of electricity generation - 85% of generation capacity being retired in 2022 will be coal[1] - and there hasn't been a new large coal plant built in the US for over a decade[2]. In Europe the amount of electricity being generated by coal is half of what it was at its peak.

Meanwhile, renewables now make up about a 87% share of new electricity generation capacity in the the US[3]. Europe is similar.

Pricing the CO2 emissions cost of an EV using the dirtiest and fastest declining electricity source (coal) does not seem fair or honest to me.

[1] https://www.eia.gov/todayinenergy/detail.php?id=50838

[2] https://www.scientificamerican.com/article/will-the-u-s-ever...

[3] https://www.renewableenergyworld.com/solar/renewables-are-87...

Still... if you plan to add 100MW of renewable this year and retire 100MW of coal, then demand goes up by 100MW, do you now add 200MW of renewable instead, or do you delay the retiring of the 100MW of coal?

That makes little sense to me.

Your analysis would result in the conclusion that charging an EV in France (90% carbon free electricity) causes the same amount of CO2 emissions as using one in South Africa (90% fossil fuel electricity).

The expansion of EVs has coincided with a massive drop in coal electricity share and a massive increase in solar PV and wind share, globally. Assuming that expanding EVs are being powered by coal is odd to say the least. Especially given that (at least where I live) 70%+ of EV charging is done at home, mostly using off-peak electricity, which tends to have a much higher renewable share.

There are many, many assumptions to such calculations. Here's PG&E's best guess at g CO2 / kWh based on time of day/year in California (page 2):

https://ww2.arb.ca.gov/sites/default/files/classic/fuels/lcf...

If you only charge from noon to two in Q1, then use have zero marginal emissions per mile driven (this is the best case). If you only charge from 7-8pm you emit 142.06 gCO2e/MJ.

1 megajoule = 0.2777777778 kilowatt-hour

Converting gives us ~512 g CO2e per kWh.

Car efficiency is measured in miles per kWh. 4 miles per kWh is doable (some cars are better, some worse). So, that's 128g CO2e per mile.

50 miles per gallon would be great. A gallon of gas emits 20 lbs CO2, or 0.4lbs per mile, which is 181 grams per mile.

So, if you only charge at the worst possible time in California (basically forcing PG&E to use natural gas plants to charge your car), then a 50 mpg car is still 50% worse than a slightly larger EV.

In practice, you charge during off peak hours. At night, emissions are about half worst case. During the day, they're 10% of worst case.

If you just apply CA's 49% natural gas (according to DOE) to the 45 mpg for 100% natural gas you come up with a gas-burning car needing >90 mpg to be cleaner -- well higher than the 70 mpg you calculated vs charging on natural gas -- but easily achievable with hybrids.

I feel like there are many people who see 30 coal / 45 nat gas and take offense that it doesn't make EVs sound particularly good. This is why I called it a more honest presentation because EVs in terms of CO2 are fairly bad in WV and marginal in DE or MI or many other places compared to a high-mpg regular car. Instead of taking offense and setting out to correct the record, understand that not sounding particularly good is an accurate view.

Even in CA, the mpg needed to be cleaner than EV formulation makes it clear that driving a 100 mpg hybrid for instance is so good that any further gains are of little consequence.

In the same vein as my sibling comment, the average is an average because not everyone drives a prius; tons of the US are dominated by trucks and SUVs. A more informed metric would be comparing EV vs ICE in cities based on those cities' percentage of electricity generation and average MPG based on the car population.

> Is it more dirty than diesel emissions? I have no idea, but old diesels were nasty.

When comparing old diesels to old coal power plants the power plants win by being more efficient but both belch out a lot of pollution. They also have the advantage of burning coal, a fuel which is available in abundance and does not need as much processing as crude oil does to be used in diesel engines.

When comparing old diesels to modern coal power plants this is true at an even higher level since those modern power plants filter out fly ash and are more efficient.

When comparing modern diesels to old coal-fired power plants the diesels win by being less polluting and possibly on terms of efficiency.

Modern diesels versus modern coal power plants goes to the power plants again since these win on terms of efficiency - especially when using combined heat & power - over the diesels.

I have found measuring in typical American neighborhoods that PM2.5 is raised the most when people burn wood for recreation or heat in the evening. It is much higher in the evening with a few neighborhood fire pits than during rush hour with a few diesel vehicles around.

This is also when residents have asthma symptoms too. To be fair they are more likely to be home.

So it is not cut and dry but if possible I would love to get rid of vehicle emissions as some particulate is too fine to measure.

So what? You can try and clean up both. Particulate is not the only pollutant either. NOx and ozone are also emitted from diesel cars.

Agree, just saying vehicle emissions are part of the picture and more work needs to be done on air quality.

We can make power plants cleaner, and generally we do (but not nearly fast enough).

Electricity generation CAN be done cleanly, and should in the future continue to get greener.

ICE cars will always give off pollution.

The thing is that we're going to burn coal no matter what.

downvotes to ask a question? what has HN become?

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