[jaxbot]

Seems like misguided faux environmentalism, like banning plastic straws but keeping the longtail of plastic waste. Electric buses are good, of course, but a well-designed and highly utilized bus network, even with the dirtiest diesel engines, is going to get you serious wins over GHG/CO2/VOC emissions from automobiles if you can replace those trips.

[bryanlarsen]

Certainly we don't want to make perfect the enemy of the good: given a fixed budget we're probably better off buying 2 diesel buses rather than a single electric bus.

But don't forget particulate emissions: I believe that's the primary motivation for electric bus conversion. Buses are a significant portion of particulates in many cities, and particulates kill people.

[NickM]

given a fixed budget we're probably better off buying 2 diesel buses rather than a single electric bus.

I think the situation is a little more complicated than that. Electricity is a much cheaper fuel than diesel, and maintenance costs are lower for electric vehicles too, so in the long term electric buses may end up saving more money than they cost.

Add to that the fact that interest rates are very low right now, and it may even turn out that financing the electric buses and charging systems could allow cities to save money from day one, though I haven't crunched any numbers so this is admittedly just speculation on my part.

[semi-extrinsic]

> maintenance costs are lower for electric vehicles

I think there is a <citation needed> here. Do ICE drivetrains really constitute a large fraction of the maintenance costs on cars and buses? In my experience, suspension and steering, and auxiliaries, are the things that break.

[vvanders]

My anecdotal evidence of ~90k miles on our EV says yes. A coolant flush, tires and windshield wiper fluid are the only things I've done in that time.

Compare that with Brakes, Oil changes, Transmission service, DPF + DEF and the host of other things you get with a diesel engine + transmission.

We've got a diesel truck, diesel tractor and EV, it's pretty easy to see the maintenance differences between the three of them over the years(the tractor being the highest with the added complexity of a hydraulic system).

[crummy]

I don't know anything about cars. Why did you need work done on your brakes on a diesel but not on an electric?

[tialaramex]

The EV gets to just run everything backwards when you step on the brakes. This won't stop you, but it'll make a huge difference to the remaining force needed to stop you, so it massively reduces wear on brakes and (which is why they did it) increases the effective range of the vehicle. And since they aren't worn out, the brakes need maintenance far less often. Driven gently the brakes on a EV might last its useful lifetime.

You can't do this with ICE, if you put diesel fumes in a compression chamber and pump the cylinders up and down, it doesn't turn back into diesel fuel, combustion isn't symmetric, so you need to actually have brakes.

[opencl]

Electric vehicles and hybrids use regenerative braking from the motor for a lot of their stopping power. They do still need brake work but significantly less often (100-200K mile interval vs ~50K though there is considerable variance depending on driving habits) because the friction brakes are engaged less often and so wear down more slowly.

[petre]

Electric braking, useful 90% of the time to slow down. Hydraulic brakes only get used for a full stop. It's like engine braking on steroids and fully integrated into your brake pedal so that you don't need to know which brake system operates at a given time.

[coryrc]

Regenerative braking

[rlucas]

I doubt it's due to the EV's regenerative braking; if anything, that's a more complex system with more things that can go wrong.

The answer is probably easier: a Prius is 3300 lbs and a Dodge Ram is 6600 lbs and carries much, much more if working. Those truck brakes are going to be thrashed much harder.

[sitharus]

Certainly suspension, steering and auxiliaries are the things that break, but every year (or 15,000km, or whatever your manufacturer recommends) you need to replace the engine oil and filter. Less frequently you need transmission fluids, coolant, air intake filter, brake pads and other consumables. On diesels you also need to refill the emissions compensation tank (the one VW cheated with), replace particulate filters. Heavily used vehicles need these replaced more often.

Electric motors will need their bearings replacing eventually, but they have no transmission fluids, no circulating oil picking up combustion products, and regenerative braking removes a huge amount of wear on brake pads.

I have a plug-in hybrid (EV infrastructure isn't great where I live) and after 2500km the brakes still stick like new. They've barely been used.

[petre]

Yes. Fluid changes, filter changes, brake pads, clutch maintenance, sparkplugs, injectors etc.

[barney54]

Particulates are one reason most city buses in the United States now run on natural gas. That's a real improvement over diesel in terms of particulates.

[supergauntlet]

One big question I have is why LPG isn't a bigger thing for cars. Regular gas and diesel engines can be (relatively) cheaply modified to run on LPG and indeed can often run on both. It's a cleaner burning fuel than both gasoline and diesel AND is cheaper to boot.

[rjsw]

A friend had a LPG conversion for a car, the tank took up a lot of luggage space. A larger tank for the same range doesn't matter as much for a large vehicle like a bus.

[bobthepanda]

It’s also not abnormal for equipment on a bus go onto the roof.

[tastygreenapple]

I think it's because most people don't understand the benefits of LPG fuel, and LPG vehicles incur costs similar to other alt-fuel vehicles without enjoying benefits.

Honda used to sell a natural gas civic and you could buy a home fill station, in the late 2000s it probably made a lot sense. But now, you'd be better off getting an electric vehicle and a home charger.

I think LPG is interesting, but if you're going to deal with speciality fuel/fueling, you can just get a hydrogen or battery electric vehicle and enjoy the benefits of an electrified powertrain. LPG powertrains retain the complexity and service costs of gas powertrains with pretty marginal benefits. Electrification has its own costs but unique advantages.

[gattilorenz]

> LPG vehicles incur costs similar to other alt-fuel vehicles without enjoying

Not universally true. In Italy, where regular gas prices are stellar, LPG is a relatively common thing. Not common enough, but the infrastructure is "there" (although not as capillary as regular gas) and it's advertised as a consumer option.

[tastygreenapple]

You're right, I was American-centric. It's a land littered with gas stations and finding other fuels can be extremely challenging.

[i_feel_great]

In the case of New Zealand from the mid-70's to the early 80's, CNG (compressed natural gas) was subsidised by the government and there was a very large uptake. My dad had it installed in his Toyota Hiace van and Ford Falcons. This was during the oil shortages era.

When oil became cheap again, the government stopped the subsidies and it was back to petrol. The tanks and the pumps at the services stations were ripped out and sold to the Indians, Eastern Europeans and the Chinese.

[inferiorhuman]

Worse fuel economy and increased engine wear are probably the big issues.

[opencl]

At least newer diesels are a lot better about particulates than the older ones, the EPA has mandated particulate filters since 2007 and they reduce them by ~85-95%.

http://www.meca.org/regulation/us-epa-20072010-heavyduty-eng...

[bradknowles]

That's assuming you actually believe the numbers haven't been rigged, VW-style.

[ComputerGuru]

The crazy thing about the VW scandal: their cars still met the legal requirements for maximum allowed emissions even without the cheat module (at least here in the USA)!

[opencl]

How would they possibly rig the numbers on a particulate filter? The cheating was achieved through engine control software selectively disabling parts of the emissions control system when it detected testing was not occurring. You cannot use software to selectively disable a particulate filter bolted onto the exhaust pipe.

[seanmcdirmid]

My city has upgraded to hybrid and NG buses in the last decade (in addition to some non battery very old and new trolley electrics), there are plenty of solutions in between dirty diesel and clean electric that have to be considered as well.

[dsfsafasfasf]

For particulates you can switch to CNG, and you can probably convert the diesel engines to run off that too.

[elihu]

Also noise.

[WhompingWindows]

It's neither misguided nor faux environmentalism. As a cyclist, going behind buses is straight toxic. Maybe you're a car user and you don't mind the dirtiest diesel engines, but those particles poison the lungs of our citizens and that nasty emission discourages people from using buses and cleaner transportation modes.

We must move to electrification if we want to save our lungs and our planet. No amount of dirtiest diesel is going to save us.

[ajross]

> As a cyclist, going behind buses is straight toxic.

Maybe[1], but still less so than the equivalent emissions from the dozen or so passenger vehicles that bus replaced.

The upthread point (which is correct) is that the environmental gains from bus transportation are concentrated in the efficiency gains of shared vehicles and that the relative impact of the fuel used is fairly minor. Get people on buses, then optimize. The linked article is worrying about things in the wrong order.

[1] I mean, no, not really. Diesel exhaust stinks, it's not particularly "toxic".

[hollerith]

>Diesel exhaust stinks, it's not particularly "toxic".

You might know your body well enough to be able to tell that it is not particularly toxic to you personally, but please consider the possibility others are more vulnerable it (because for example their bodies have more chronic inflammation than yours does).

The URL below goes to an article not about diesel exhaust or pollution, but about chronic inflammation, entitled "Understanding inflammation". Here is all the advice near the end of the article on how a reader might reduce inflammation. Emphasis mine.

>“Losing weight can have profound effects on lowering inflammation,” says Brown, who adds that eating a diet rich in fruits and vegetables and low in fats, processed foods, and sugars is generally a good idea, though more study needs to be done to determine how it might affect inflammation. Exercising, which causes an acute inflammatory response in the short term, but an anti-inflammatory one when we regularly get moving, is another strong step to take, he adds. Other researchers advise getting plenty of sleep, lowering stress levels, and seeking out treatment for inflammation-inducing culprits, such as gum disease and high cholesterol levels. Avoid contact with heavy metals such as mercury, which is found in dangerous amounts in some large fish, and limit exposure to substances, such as diesel exhaust and cigarette smoke, that can set off the immune system.

https://www.johnshopkinshealthreview.com/issues/spring-summe...

[ajross]

I don't know what the argument here is. Obviously you don't want to be sucking down diesel exhaust, and I don't believe I set a stake down on "diesel is good for you".

My point was that, on balance, riding in a bike behind a diesel bus is less toxic than riding behind the train of 10+ cars it replaced (or really that riding in a city filled with single passenger vehicles is less healthy than one inhabited by diesel bus riders.

Get folks out of their cars. Then worry about what kind of buses they ride.

[martythemaniak]

You seem fixated on cars emitting stuff. Riding behind any vehicle that burns and releases any fossil fuel sucks, and all those vehicles should be replaced. In fact cars are quite a bit ahead of busses.

[hollerith]

My argument is that maybe not for you, but for many people the exhaust from one diesel bus is worse than the exhaust from 10 or 20 gasoline / petrol cars. The article I linked to makes no mention of any kind of pollution except for diesel exhaust.

(In California, where I live, the vast majority of cars are gasoline / petrol cars.)

[ajross]

So... you're genuinely advocating against the use of public transit? Seriously?

[dsfsafasfasf]

It's not toxic in an acute sense, but it's equivalent to cigarette smoke and chronically terrible for you (I love smoking and diesel, btw). Both are low T impartially combusted complex hydrocarbons that generate a stew of different nanoparticles and reactive species.

It's terrible stuff!

You can argue that it's benign in the middle of nowhere, where the concentration drops to nothing quickly. But not in the city!

[deagle50]

Except that diesel emissions kill city residents.

[StreamBright]

So does coal power plant emission.

[r00fus]

So add solar+wind into your jurisdiction's power mix. It's not hard to do, and progressively the diversity of power will be more stable than just relying on the coal plant which will get shut down.

EV buses allow you to wean off carbon power sources in many stages.

[StreamBright]

Sorry I would like to run buses when it is dark or when the wind is not blowing.

[Brometheus]

Well, they run on batteries.

[StreamBright]

I see, how long they run with one charge? Are you implying that worst case the buses are charged with nuclear or coal energy?

[imtringued]

I am speechless.

[StreamBright]

Sorry if you have nothing to add here.

[munk-a]

I don't mean to suggest that power generation modernization isn't important but... it's pretty beside the point, investing in diesel buses is locking that usage in for a great many years while an electric bus may be eventually powered by coal initially then transitioned over to an alternative energy source.

[merpnderp]

I’d argue for diesel buses because wind and solar already strain keeping the electric grid stable, except it won’t be a coal plant, it will be a natgas plant, which by itself is a huge win over diesel motors in a big city.

[deagle50]

Are you really comparing pedestrians inhaling NOx directly from tailpipes to a remote power plant?

[sokoloff]

Isn't it the particulates in diesel emissions that are particularly more harmful than other internal combustion engines?

NOx promotes low level ozone, which is an irritant, but I thought by far not the differentially harmful portion of diesel exhaust.

[StreamBright]

Yes I do.

https://ourworldindata.org/co2-and-other-greenhouse-gas-emis...

https://ourworldindata.org/grapher/carbon-dioxide-co2-emissi...

https://blog.mybacharach.com/articles/sources-nox-emissions/

I know your feelings is as good as data but still.

[gataca]

Centralized coal power plant outside of the densely populated areas that buses concentrate in >>>>> mobile pollution machines in those same dense areas.

Seems rather obvious

[StreamBright]

Volume of coal power plant >>>> mobile pollution machines.

The 7 out of the top 10 CO2 emission sources in Europe are coal power plants. Their production is blown by the wind to populated areas. Some of coal power plant production ends up different countries as well.

https://www.theguardian.com/environment/2013/oct/15/european...

[woodandsteel]

>Electric buses are good, of course, but a well-designed and highly utilized bus network, even with the dirtiest diesel engines, is going to get you serious wins over GHG/CO2/VOC emissions from automobiles if you can replace those trips.

The long-term plan is to electrify both the buses and the cars, and also the trucks, and to do that in a reasonable amount of time, you need to work from now on at all of them at once.

What's your long-term plan?

And by the way, most of these cities already have a big diesel network. But let me ask again, what is your long-term plan?

[dsfsafasfasf]

"even with the dirtiest diesel engines, is going to get you serious wins over GHG/CO2/VOC emissions from automobiles"

Not for particulates. Even a clean diesel bus is going to be dirtier in particulates vs. gasoline. Its the nature of the fuel (i.e. not the thermo cycle used).

ON the other hand, converting to CNG eliminates particulates completely (you use the same engine, just feed it CH4)

[eeZah7Ux]

> even with the dirtiest diesel engines, is going to get you serious wins

This is true: more public transport should be the n.1 priority, even if it's diesel.

However you are creating a false dichotomy: electric VS diesel.

We can have more public transport and electric transport at the same time. Less cars, thanks.

[StreamBright]

Depending on what is the source of energy used to charge the buses.

[tropo]

That "well-designed and highly utilized bus network" is the hard part. I've never seen it.

Around here the buses run pretty empty. Sometimes they are literally empty. They take longer routes than cars, with each passenger going a longer distance because the bus route is not what they really want. It would be far better if the passengers had cars.

[esoterica]

You’ve never seen it because you live in a city with garbage transit.

(It would not be better if all the passengers had cars, because then it would lead to greater congestion and it would take everyone 2 hours to go 10 miles.)

[crummy]

Wouldn't the proper solution be to improve the bus routes?

[closeparen]

Bus routes are already subject to pretty sophisticated optimization. You can push utility around to do different segments of the community depending on your political priorities, but there aren't global optimizations just sitting on the table. Unless your transit agency is really incompetent, in which case you have to ask why your call to "improve the bus system" today will fare differently from all those that came before.

[tropo]

If that were possible, it should have already happened.

The bus just isn't going to take people point-to-point. It will go to a hub, and then people will change buses, and then another bus will go out. Point-to-point service is personal transportation. Shared transportation fundamentally can't be optimized to individual needs.

So the buses drive longer distances, and they have to drive even when empty.

BTW, bus usage can seem better than it really is. You are likely to go on the popular parts of the routes, so you see the buses being fuller than they usually are.