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After bus fire, CT pulls electric fleet from service (ctinsider.com)
59 points by starkd on July 26, 2022 | hide | past | favorite | 139 comments



While this is unfortunate to have happened, this says more about CT being smart and having an over abundance of caution, than lack of faith in a technology.

BART, which has been running for 50 years recently [1] had an issue with the heat that caused a train to derail. For several days that section of track was totally shut down. For weeks afterwards they ran the trains at an extremely low speed through the miles of surrounding track - for safety. It's been a month and I'm honestly not sure if they are running "at speed" again yet.

It's good to be cautious when you don't know the cause of an issue or aren't sure what happened. Someone could have shot the bus's battery... or it could be wired in a faulty manner... or they could have a design flaw. Lots of options, good to ground them until you know why. Lest we have another MAX8 debacle.

[1] https://www.eastbaytimes.com/2022/06/21/bart-train-partially...


Why don't we pull diesel bus fleets off the road whenever there is a diesel bus fire?


Complacency.


My take on 737MAX tragedies was lack of FAA diligence. Relocating engine mounts to squeeze in the oversized engines should have required the type certification process. Instead the FAA looked away and approved a software layer to make it seem similar to existing 737s so pilots could avoid re-training for what would be a new type certification.

That was regulatory failure while a bus battery fire could be a one-off manufacturing defect.


Yes. Good thing to ground them, but it also shows these vehicles are not ready. Even if its an act of sabotoge, like someone shooting at the battery. It would not happen with a regular diesel bus.


Umm, it did. In CT. Last month. https://archive.ph/FZ2wv


I think the difference here is that an EV battery fire quickly spreads to the entire length of the bus, because the battery spans the entire length of the bus internally. Whereas the diesel fire is contained to the fuel tank and engine block, which could allow passengers to more easily escape to whatever end of the bus isn't on fire.

New battery chemistries like LFP should solve the thermal runaway issue.


> I think the difference here is that an EV battery fire quickly spreads to the entire length of the bus

It's an interesting theory, but I don't see it supported by these articles.

The entire diesel bus had its back third engulfed very quickly, from these sources.

The entire electric bus burned, but we don't have any information on the rate at which the fire propagated.


If anything an EV should be possible to design to be safer against fires, as it's the battery itself that burns. A metal fire break on the floor and a gap between that and the battery should give warning signs (smoke coming out the sides) and give people time to evacuate before it becomes too serious. Temperature sensors throughout the battery could give warning signs even before it gets to that.

In an ICE vehicle it's the vapour of the fuel that burns. The engine of buses/coaches is typically under the floor, with access panels, so vapour can easily get into the cabin.


No, the bus batteries involved here do not propagate quickly. When it can't be contained, it takes more than 20 minutes to spread, which is plenty of time to evacuate the bus.


I don't see anything in this article about someone sabotaging the fuel line. In fact, they don't even mention how the fire started at all.

Why is this article relevant?


Here's the comment flow:

> Even if its an act of sabotage, like someone shooting at the battery. It would not happen with a regular diesel bus.

He's saying, even with sabotage, it would not have happened with a diesel bus.

Then a link was posted showing a diesel bus catching fire, no sabotage required. Diesel vehicle fires aren't some impossibility, as a quick google search will make clear.


Well yeah, you can forcibly set anything on fire if you want to, the comment was specifically referring to compromising the fuel system of the diesel vehicle, which we have zero information to indicate was the cause.


Shooting the battery pack won't cause the pack to do anything quickly. People would still have plenty of time to get out.


I think it's fantastic that smaller-to-midsized towns are bringing EV buses into service, but I'll mention my perennial bugbear again: all of these towns had dedicated trolley service under a century ago. The lines were torn up and replaced with less frequent, traffic encumbered bus routes.

Hamden, for example, had three lines between it and New Haven[1].

[1]: http://www.hamdenhistoricalsociety.org/trolleys.html


Very true. For the disbelievers, have a gander at this fine map: https://www.flickr.com/photos/115892967@N03/49373818816

Be sure to zoom in all the way—the interurbans of Michigan, Ohio and Indiana are not restricted to the red lines, the black lines (marked up with an indication of the company running it and circles for stops) are covering the entire map in a fine mesh. Legend has it that for some time you could ride from New York to Chicago by hopping from one interurban to the next, with a gap of a few miles in-between that you would have to cover with some other mode of transportation. All those who claim that public transport is infeasible neglect that it used to be very feasible. This map does not show local streetcar lines, e.g. here's a 1940s map of Detroit streetcars: https://detroitography.com/2013/10/12/detroit-streetcar-rail...


Always love myself a good ol' trolley. Those things are beautiful.


Yep, this is another perfectly good reason to want them: they're just pleasant to look at. They instill civic pride in a way that a street with honking cars cannot.


Trolleys have a fixed route, which is not ideal. Fixed routes is why you see buses going down the road empty, or with one person on them.


I don't understand this point. Buses don't have inherently fixed routes, so that isn't why they go down the road empty. It's because, in many places, their routes haven't been replanned to compensate for suburban sprawl, and their service is bad.

The fixed-route nature of trolleys is not an inherently bad thing. In fact, it was the dominant (and eminently sustainable) form of urban expansion for over 75 years[1]. It turns out that fixed routes mean stability, which in turn means that businesses feel comfortable investing in long-term presence. Residents similarly find them desirable, since they can be certain that their streetcar won't be taken away from them (unlike a bus).

[1]: https://en.wikipedia.org/wiki/Streetcar_suburb


> Buses don't have inherently fixed routes

In my city, they haven't changed the bus routes in several decades.


Right, that was the point about bad service: trolleys and buses can have stable routes but, paradoxically, that stability is generally good for trolleys and not good for buses.


Stability is good, but only to a point. A bus can divert around double-parked car, or a closed road, but a trolley is stuck until the blockage is cleared.


This is absolutely true, and is why both European cities (and slowly, American cities) have taken pains to minimize interconnections between trolley and automotive traffic.


I'm surprised this comment is so controversial.

Imagine if a bus had on demand stops, rather than stopping at 50 empty stops to get from point a to b. Those 49 extra stops are why nobody uses buses. It literally takes 4 flipping hours to go as what it takes 20 minutes by car, all while on a mostly empty bus, taking a fixed route, with fixed stops. Maybe it's better in other parts of the country, but in every city I've lived in, including San Jose, the nobody uses the buses, because nobody has that kind of time.

Trolleys for congested down town areas, sure.


For what it's worth, I think it's unreasonable that it was downvoted.

But also: most municipalities that I know of do not require their buses to make stops if nobody is either waiting or signaling to get off the bus. NYC goes beyond that, and allows you to request a drop-off anywhere along the route during night service[1].

[1]: https://new.mta.info/guides/riding-the-bus


FWIW, I've never heard of or seen a bus halt at an empty stop when no one on board wanted to get off. The only exception to this is if they are running ahead of schedule, in which case a halt to return to the set timetable is the right thing to do.

Maybe this behavour is very locale dependent?


> Maybe this behavour is very locale dependent?

That could be. Maybe they were ahead of schedule the few times I went, and the few times I observed them stopping at empty stops. This would make sense with the fact that they are almost always empty. They would come to a complete stop, open the door, immediately close the door, then peel away. It was comically discouraging. With the stop near my place, they would often just drive up, slow down to walking pace, then speed off.

Even if they were ahead of schedule, this would still mean the posted trip times were still many times greater than driving, which I assume is why they're empty.


I get that this bugs you, but what does it add to the conversation today? Those lines are long gone, and it's not like complaining about it will bring them back.


These lines would be unambiguously better (cheaper, much simpler materials, much less embodied carbon, faster and more reliable if given a proper right of way) than a bunch of electric buses in shared traffic so it makes sense to bring them up.


How is building dedicated trolley tracks cheaper than buying a bus and running it on ordinary pavement?

And streetcars have no reason to be faster either. It's easier and historically faster to have a dedicated bus lane than a dedicated trolley lane, but there's just not enough will for even that.


I won't make the claim that trolleys are cheaper, in terms of initial capital. I will make the claim that they're more sustainable, in the following senses:

* They make their neighborhoods more valuable to both residents and businesses, which in turn prevents neighborhood flight

* Streetcars cost less over time, after their initial cost. Portland found that streetcars cost the city roughly half as much per ride as buses do, and streetcar bodies themselves last much longer than buses do[1].

Ultimately, however, we're talking about public infrastructure. It shouldn't be beholden to the lowest cost; we should be balancing cost with benefit.

[1]: https://www.vox.com/2018/7/13/17570156/us-streetcar-trend-pu...


> Portland found that streetcars cost the city roughly half as much per ride as buses do, and streetcar bodies themselves last much longer than buses do[1].

This is the same order of saving gained by switching high traffic bus routes to EV busses, since fuel is the main cost, (Lower EV maintenance is also a benefit shared by battery busses) so its a very weak claim to superiority for electric trollybusses or trams without batteries, and one that will, if it even exists today, erode over time as batteries improve in cost and performance.

EV busses are similarly an up front cost for continual future savings. This is already a key part of their appeal. People buying scores of busses know their way around a spreadsheet.


Sure; don't get me wrong, I'm a big fan of more bus routes! If EV makes those buses cheaper to operate, that's a big win in my book.


Dedicated bus lanes almost match dedicated trolley paths for on time reliability but it doesn't address the fact that over head wire trolleys are still much more environmentally friendly than battery feed buses. You can even do over head wire trolley buses if you are absolutely wedded to never touching existing pavement. My point really is more that over head wires are so much better for vehicles with set routes than batteries


When trolley lines were new, they competed with horse-drawn carriage traffic for fast transit, and they just ran continuously at very slow speeds without stopping. Nowadays you can ride an e-bike faster than a horse and cover those routes in less time...except that all of the lines have stops for cars.

Basically, all the old trolley lines have a lot of trouble in the present-day context because the traffic appeared around them, and once cities succumbed to the desire for lots of parking, the die was cast - you had to also give cars most of the routes. And then it's pulling teeth to get a modest 1 MPH improvement out of some trolley corridors with careful stop alignment and signalling.

If we separate out the rights of way well it's a different story, but then we are talking about a more substantial build, and when that happens a busway becomes the way to do the mass transit cheaply upfront and get the most impact immediately.

Everything really comes back to the geometry, not the modality. When there's dedicated space the difference between rails, overhead lines, and battery is just a spreadsheet calculation. But as soon as it's mixed traffic battery shoots to the top because of its flexibility.


Not really, because you can rework bus routes about 10,000x easier than rerouting trolley lines. If there are very dense, well defined lines, then sure trolleys can be better.


And yet bus routes don't change that often. Let's say it would take 10 years to change a trolley path (an insane time frame but it's the usa so...), I don't see any bus routes changing 3x a day. It is easier to reroute but the difference is only really like 2-5x. And with the trolley you can actually be confident of it showing up on time :)


It's not safe on HN to tell the more obvious lies about EVs, renewable power, climate change etc. that are popular in certain circles due to the more technical audience so you get a lot of people with unusually strong views about how obsolete tech X is actually better for the planet than the solution that experts in the field have settled on.

Can't have people believing that experts and democratic governance is capable of performing even basic functions or the next stop is communism.


> the solution that experts in the field have settled on.

1. The "experts" ain't always actually experts

2. They haven't settled on anything, judging by the abundance of trams and lightrail still in service.


There's no one size fits all answer, and scrapping existing infrastructure is not a high priority but...

The basic shape of the future is electric powered and with batteries. Even for areas with existing overhead line systems, adding batteries is a no brainer, as it simplifies complicated junctions and a thousand other annoying edge cases. And extending the system with electric busses for less busy areas is also a no brainer (which they probably already do with some other kind of bus).

As batteries plummet in price the distance between recharges can be stretched, current models have like 10km to 30km autonomous range, which means they're basically battery busses with in-motion charging.

Battery busses are a global oppprtunity, with massive cost savings over existing alternatives today and the benefits of scale will quickly make them better than the trams and trollybusses that only work in specific locations, even in those specific locations that they are great for. They'll improve, just as an offshoot of the wider EV revolution but long term they're an obvious dead-end.

In motion charging will be something you do to get even cheaper electricity costs by managing demand, not something you do because batteries are too expensive or heavy. And induction charging at stops may well prove a better investment if it can be shared with other EVs on the road.

In short, in a world with cheap plentiful batteries and electricity, full of a thousand other types of battery EVs they don't make sense. Anyone advocating for them is basically arguing against cheap, plentiful batteries existing, which if it was true, would be the real problem to solve. But it's not.


IMO this is an aspect of the shift to EV's that I don't hear all that many people talking about- is the gov giving enough resources/training to local emergency services providers to deal with these sorts of fires and the disposal of the EV materials after a fire. Totally surmountable, but I feel like I don't hear the federal gov talk about it much and instead the focus is on more chargers and tax credits to eliminate range anxiety and drive the cost down for consumers


> is the gov giving enough resources/training to local emergency services providers to deal with these sorts of fires and the disposal of the EV materials after a fire.

The main immediate threat is not disposal or even fire itself but the release of hydrogen fluoride _during_ a fire. You have to avoid airway and eye exposure at all cost with HF. This is probably the main difference in an EV emergency response as opposed to other chemical fires.

The second main issue is securing an electrically safe chasis during crash and vehicle extraction (if you need to start chopping the car up to extract someone), you need to know what to cut and when.

This unfortunately varies wildly, model to model, with manufacturers adding battery packs in multiple locations for space and weight management. I know there has been a lot of effort in standardizing charging systems, perhaps we also need some form of emergency service kill switch, but this being HN that could also introduce a massive potential for abuse.


Many models have a pyro fuse in the battery pack high voltage hook-up that blows when the airbags deploy. Also common is that if the 12V battery is disabled, the high voltage pack is also disabled. And many models simply disconnect the high voltage pack when in park (or soon thereafter).

So while you're right that there's not a common standard, the common reality is that the packs aren't dangerous in a crash. Regulation could push this just a little further and mandate pyro fuses in pack hookups, which would reduce the probability of electrocution to first responders and occupants to basically zero, since nobody would try to cut through the floor of the vehicle in an extraction (where the pack cells are, and the most dangerous part when it comes to randomly cutting cross sections.)


All EVs and hybrids have contactors inside the battery pack and if it is not energized, there is no high voltage present anywhere in the vehicle outside the pack.


> The main immediate threat is not disposal or even fire itself but the release of hydrogen fluoride _during_ a fire. You have to avoid airway and eye exposure at all cost with HF. This is probably the main difference in an EV emergency response as opposed to other chemical fires.

At any chemical or vehicle fire, firefighters are wearing SCBAs.

> The second main issue is securing an electrically safe chasis during crash and vehicle extraction (if you need to start chopping the car up to extract someone), you need to know what to cut and when.

HV cables are extremely clearly marked (bright orange, a color not used for any other component.)

HV cables run directly from the battery to the inverter. Extraction involves prying doors / cutting door hinges / cutting roof pillars. Not chopping up the floor.

HV cables are not energized after a crash because every battery, EV or hybrid, has an internal contactor that fails safe. There is also usually a clearly marked physical plug that can be pulled.

I love it when people jump on internet forums and talk authoritatively and demonstrate they know absolutely nothing about the subject at hand.


The entire point is that you can't "deal" with it. Since car batteries contain the fuel and the oxidizer, there isn't a way to separate them short of blowing the whole thing up. Fires can stop and start spontaneously, and often do (see pictures and videos of Teslas on fire in junkyards).


Electric cars could totally be designed to be re-ignite-proof.

For example, you'd have the battery pack detect a breach - for example through a lack of pressurised coolant.

That would then trigger each battery cell to have a PTC resistor discharge it - that could be entirely mechanical.

The PTC resistors would discharge the battery in a few hours, maintaining the battery temperature at say 120C. As water is doused onto the battery, it will boil off.

As soon as the battery temperature cools below 120C, then every cell is guaranteed to be discharged.


How well do these safety feature survive 2,000+ºF fire burning next to them?


PCB solder will reflow at about 240°C or 470°F so provided you have a thermal resistant container around the pcb it will probably outlive the fire long enough to fail-safe, these kind of hardware mitigations will probably latch with a latency in the microseconds scale.


Badly. How well does gasoline containers survive it?

If you have a 2000°F fire, you probably have buildings collapsing and a lot of fire everywhere surrounding it. As long as things do not explode, you can't make it much worse by any action. And exploding is something the batteries don't do.


there’s a period of time between normal operation and 2000 degree fire where this could be detected


So in a thermal event, where integrity of the coolant is compromised, you want to dump more heat into the system?

Its not just the electrical issues at play, its the fact that hot battery fluid burns spontaneously with exposure to air (I suspect also water, but I'm less sure about that)


A PTC resistor only dumps heat if the system isn't already hot. PTC resistors can be designed which will survive a car fire.

It's a good way to ensure that the only way the system can appear safe (ie. cold) is when all batteries are discharged, therefore preventing re-ignition.

Obviously you could also have an external energy dump for that purpose (for example power up the cars 5 kw resistive heater for 10 hours), but that's both far slower than boiling water at scale, and won't work after major damage which is likely after a car fire.


> The PTC resistors would discharge the battery in a few hours, maintaining the battery temperature at say 120C

Thermal runaway in lithium ion batteries starts at 100C and is a significant danger at 60C.

Maybe learn more about subjects before you come up with all these opinions on how things should be done.


Only in unpressurized cans. Pressurized sealed cells can have much higher thermal range, which is why nearly all EV manufacturers use them.

For example, even DEC can be made safe to 175C at 3 bar[1]. 3 bar isn't a lot for a liquid filled metal can.

[1]: https://upload.wikimedia.org/wikipedia/commons/a/ae/Vapour_p...

Obviously they can still suffer thermal runaway, but it happens at much higher temperatures.


This is not really true. There are tools and agents to address lithium fires, but you have to have them. If you just try to put them out with water, you're going to be there all night fighting reignition.


Lithium ion battery fires are not lithium fires.

Water is the recommended method because it is the most effective way to stop thermal runaway.

If you don't believe me, google "lithium ion battery fires water"


Please don’t leave us in suspense: what are these tools and agents? Got a link?


Lithium fires are considered class B so any chemical agent such as found in any standard ABC or dry chemical fire extinguisher would be sufficient. As for tools, there's stuff that can be used to pierce the battery case and inject water or agents directly into the battery.

https://arstechnica.com/cars/2021/11/new-firefighting-tool-d...


For lithium, sand is enough. If you have HF like a sibling said, sand won't do, but I can't imagine you would get enough of it to sustain a fire.


Add to the fact that the fuel is Lithium and you’re in for a badddddd time


There really isn't as much lithium in a battery pack as people seem to think. The 450 kg pack in a Model S has about 60 kg of lithium. Dutch fire fighters dump the whole car in a skip full of water to cool it down once they have contained the fire so that it burns out but doesn't set light to anything else.

60 kg is roughly 9 kmol and 1 mol has a heat of combustion of 300 kJ/mol so if burnt in air it would release 3e5 * 9e3 = 27e8 J which is about 75 kWh (coincidentally about the same as the battery capacity). Enough energy to raise a ton of water by 67.5 K. So if you can submerge it in water it will pose no further risk.

I presume that the lithium water reaction releases a similar amount of energy if the hydrogen burns, someone with a better knowledge of the chemistry could correct me.


Im a Vol Firefighter in a Major City Suburb with lots of highways and tons of crashes. We get 2-3 car fires and passenger extractions per month. The first question we ask on the way out is "Is this an EV?"

We need to know this because EVs trigger the rollout of Water Tankers from surrounding towns, as many as we can get. Usually a Water Shuttle has to be set up. Not many Fire Hydrants on Highways, and EV fires require A LOT of water, like several house fires worth... Here is some external detail on this - https://www.businessinsider.com/tesla-crash-fire-lithium-bat...

Also, we need to start calling more manpower. EV fires burn a very very long time while ICE fires are usually put out in the first few mins, and with 1 engine's 1000gal tank water.

Adding to this, the fire is usually under the car, and quite hard to get too. We are very good at opening locked car hoods and cutting metal to get at the fire, but when its deep in the guts of the thing, its impossible. At my department, we have started working on ways to jack the car up safely while its on fire so we can get water onto it. Trust me, its even harder than you would think...

The Standard Operating Procedure is to put water on the car and surrounding area so that nothing else catches on fire, but basically we have to let the thing burn out, and that can take hours and hours...

EV car batteries do not rely on the environment for their fires to burn. The fuel brings its own oxidizer, and it doesnt need anything else. We can put out Liquid Fuel fires by robbing the oxygen or removing the heat(thats what the water does), but once EV fire gets to a particular point of no return (which it arrives at very quickly) there is really nothing that can be done to stop it, just make sure it doesnt get any worse...

Here is the current thinking from the NFPA (firefighting safety and standards organization in the US), you'll see EV car fires are long on problems, but even the most focused minds in the US Fire Prevention industry are short on answers at this time. https://www.youtube.com/watch?v=Sp3WvKON_W4


I recently purchased an EV, and there is an emergency high voltage battery cutoff in the rear. Do you guys know about those, or if so, are they effective?


The cutoff is to stop the electricity from leaving the battery, and electrifying the rest of the car. Nothing more fun that getting electrocuted just touching a car. F1 cars are also Hybrids, and if you watch F1 drivers exit a the car after a crash, they do a little hop off the car. Making sure not to touch the car and the ground at the same time. They also have little indicators that show if there is current running into the car's body. I will venture that an F1 hybrid system is at least as advanced, if not more-so, than a common consumer hybrid system. At the least, I wish Commercial EVs had that same electrification indicator.

Cutting that wire is largely, to de-power airbags and the like. Airbags DO go off unexpectedly, and can inure a responder quite effectively. Cutting the power is a normal step in any big motor vehicle incident, EV or ICE.

Tesla and others do publish all this information with nice diagrams and handy mobile apps, and we study them. However, this doesnt fix the problem of the Huge Energy load in the battery itself. Even if that energy cant get out of the battery through wires, it can still burn like crazy inside (and outside) the battery case(s).


The make of the bus doesn't seem to have been reported, but maybe one of the New Flyers they purchased?

https://portal.ct.gov/DOT/Publictrans/Bureau-of-Public-Trans...


Lithium-titanate battery Seems like a better fit for in city transportation where a quick charge is possible and safety is highly desired. Not to mention the lifetime of those cells. Lithium Nickel Manganese Cobalt Oxide (NMC) Batteries have higher energy but very short lifespans and are extremely flammable in comparison. https://en.wikipedia.org/wiki/Lithium-titanate_battery


We need more electric trolley busses. These battery powered ones are nonsense


Modern trolleybuses with in-motion charging, like Dayton's latest models, will still have substantial batteries for off-wire operation.


Even then, a much lower capacity is required if the trolley bus will spend the majority of it's lifecycle on a catenary.


Yeah but a city like sf has run those for decades very safely.


Trolley buses cannot be detoured and the infrastructure costs are enormous, as is the cost of even a minor route change.

Battery technology continues to improve in cost, energy density, and charge/discharge rate. There are already systems that use a catenary-like device to "top off" the bus while it is stopped at a bus stop.


All modern trolleybuses have either batteries or diesel engines for detours.

Infrastructure costs aren't "enormous", that would be if you're putting rails in the ground for trams.


> "they emit no emissions and they last longer"

Not when they spontaneously combust they don't


This happened in China as well with a domino effect: 5 buses total https://newsasiatoday.com/electric-bus-china-caught-fire/


LION batteries are insane - to see what happens at serach for this on youtube. There are mass graveyards of e-bikes after battery suppliers where rebadging low quality cells are higher ones leading to a generation of lottery tickets. Something like 5 fires a day for e-bike, not sure of the stats on cars.

https://www.youtube.com/watch?v=el_hNwaUSfU&t=3s


Anyone know the brand of bus and type of battery pack? Can't seem to find the info. Mainly wondering if it is a NMC or NCA pack or more stable LFP pack. LFP's are much safer with much lower chance for thermal runaway but they will still burn, they are also cheaper have much long cycle life and don't use nickel or cobalt but have a lower energy density. City buses would be a great application for LFP.


> As a result of the fire, the electric bus fleet was pulled from service as a precaution, Rickman said.

> “The importance of rider safety is demonstrated by taking these buses out of service and ensuring a thorough investigation is completed prior to any redeployment of the fleet,” Rickman said.


Battery buses are a solution ahead of their time. Any old bus is better than car-based transportation, so shifting modes from car to bus is more important than changing the energy source of the bus. If shifting from car to bus is impossible because of built environment, that's the first priority. Buses powered by batteries should be way down at the end of the TODO list.

If you absolutely insist on having buses that aren't direct sources of CO2, fuel cells are a more mature technology that makes more sense than batteries.


I suspect that you don't live in europe.

In london, buses are a massive source of particulate and nitrogen pollution.

We've had hybrid buses for a good 5 years, some hydrogen ones as well (but only one or two routes)

However london has rolled out 100% electric buses in the last 3 years, and they've not caught fire at a faster rate than the diesel ones.


In London that makes sense because they already have a decent mode share. I suspect the bus mode share in Hamden, Connecticut is 1% or less.


for demand that makes sense, for justification of using EV or not, I don't think it really makes a difference.


Yah precisely the point. We should focus on making busses comfy and nice and on getting good coverage with bus routes so that people use them.

Worry about them being electric later, the environmental impact of less people driving far overshadows the impact of ev vs gas busses.


Any sources to support the claim that fuel cells are more mature?

Looking at another aspect, how many hydrogen generation facilities are there in CT, vs. facilities that can charge an electric bus?


Buses and other "same route local delivery" type vehicles are a prime candidate for electrification TODAY because the short and known daily mileage plus always returning to the same spot at downtime sidesteps a lot of the range/charger problems that push EV to be just barely not viable enough for other cases.


A bus is only better if it is full of passengers, which is not always the case.


The stunning failure of Nikola or any other large-scale fuel cell company other than Toyota to deliver working FC vehicles really calls into question your characterization of hydrogen as “more mature” than batteries. Every FC vehicle is also an EV, just FYI.

One would also wonder why China has ~0 fuel cell buses and tens of thousands of electric buses if FC is the more mature tech.


My city has a large fleet of fuel cell buses and has had them for over a decade, which suggests you don’t know what you are talking about.


So you’re saying that the the unnamed town you’re in bought a few FC buses 10 years ago and is still maintaining them today? That’s great, but it’s also an anecdote.

Have they bought any recently? Have neighboring towns bought in as well?


I see that you are doubling down on the “don’t know what you’re talking about” aspect of this debate. My local transit agency is AC Transit. It serves millions of people in several large cities. Last year it ordered fifty more fuel cell vehicles from its suppliers.

https://www.actransit.org/zeb


Thank you for sharing that link, Jeff! It’s neat to see that ACT is going for a 70% hydrogen, 30% electric mix. Their page has a unbiased-sounding section on it:

> We will be running hydrogen and battery electric vehicles in identical service to collect real-world performance data for comparison—and to determine which technology performs better to meet the needs of our service as we move towards a complete zero-emission fleet by 2040.

It looks like they started the hydrogen bus project 20 years ago, not ten.


How much emissions did that release compared to running a petrol bus?


I haven't heard of petrol buses before, you probably mean diesel or CNG. Petrol is what Americans and Canadians commonly call gasoline, which is generally used in smaller vehicles than buses or trucks, which generally burn diesel instead. Petrol is a lot more dangerous than diesel because petrol fumes are explosively flammable, while diesel is relatively nonvolatile.


Similar to a burning petrol bus.


Which happens how often?


We need more electric trolley busses. This whole battery nonsense is ridiculous


Bostonian here, I used to commute on one every day (MBTA 71 and 73), but they were taken out of service earlier this year, for eventual EV replacement.

The problem with electric trolley busses is that they can't pass each other, they perform very poorly in rain, frequently disconnect, and they need constant maintenance of the overhead wiring. I do miss it because it was a local landmark, but an EV bus will be much nicer to have.


Trolley busses can overtake each other, either by having a passing loop built in to the overhead wires or by briefly dewiring and rewiring the bus. Modern trolley busses can travel short distances off-wire and some can even rewire themselves automatically.

The only reason MBTA has had so many problems with unintended dewiring is that they have done little to no maintenance on the overhead wires for the last half century. You can expect that the same will happen sooner or later to whatever charging infrastructure they build for battery electric busses. That is, assuming that they even that far and don't just pull a bait-and-switch as soon as the wires are down.


Seattle has a great many of them but the lines for them to run on only exist in certain place, granted they are the densest places. But running that pair of electric lines everywhere is a big infrastructure project for any city.


They're willing to tear up the streets, install rails and run those slow-ass streetcars down the middle of the road.

Also I imagine that getting enough power to your charging facility to charge 50+ buses up overnight isn't going to be any small feat either.

At least with the overhead lines, you don't have to worry about charging. You don't have to carry heavy, expensive batteries either. Though you do get the occasional "derailment" where the bus comes off the line. But the bus drivers are able to fix that themselves.


As much progress has been made in EVs, I have no interest in sitting atop of a napalm bomb while zipping around town. There's a few problems that keep me from being remotely interested in EVs, this is one of them. The others are range anxiety, energy storage portability and battery replacement costs.

If I run out of gas on the side of the highway, I call AAA and they can deliver me a couple of gallons of gas or I can walk to a gas station. If your EV runs out of juice, you have to have it towed to a charging station.


The napalm bomb you're speaking of is made of gasoline. Which is in most cars and vehicles on the road. So you're less afraid of something designed to catch fire and explode (gas) than something that is designed to operate safely at it's core (batteries)? That just doesn't make sense.

Other than being afraid of new technology. And that's totally ok. Its fine to say you don't like change or new technologies. There is absolutely nothing wrong with that. In everything we've done, there is always someone willing to lead the way, and others that will follow.

And the range anxiety is not really applicable to a bus. In fact you could say this is really the perfect use case for an EV.


Diesel is generally considered a safer fuel than gasoline, it's a lot less gaseous or flammable.

That said, yeah it's not like ICE vehicles are any safer when it comes to fire hazards. They're probably easier to extinguish though; EV fires are a pain, to the point where fire brigades bring in containers, fill them with water and dump EV car wrecks into them until they've stopped reacting.


When was the last recall of a gasoline fueled car for spontaneous combustion?


Earlier this month: https://www.nhtsa.gov/recalls?nhtsaId=22V484000#vehicle

> Ford Motor Company (Ford) is recalling certain 2020-2022 Escape, 2021-2022 Lincoln Corsair, and 2022 Maverick vehicles equipped with 2.5L HEV or PHEV engines. In the event of an engine failure, engine oil and fuel vapor may be released into the engine compartment and accumulate near ignition sources such as hot engine or exhaust components, possibly resulting in an engine compartment fire.


You're both widely overestimating the fire risk. It shouldn't even be a consideration from the consumer perspective. The color of the car probably matters more.


If this (one of many) example doesn't scare you, well then you're braver than I am: https://youtu.be/sAQlLu5ttOk?t=77


I watch videos and documentaries about plane crashes all the time, and yet I am not afraid of flying because I understand the safety culture and statistics of the industry.

If you are afraid of your car, regardless of motive power source, bursting into flames without warning, then you shouldn't own a car, because tens of thousands of people die in car crashes every year, and for most of them they experienced no warning and could not have forseen their death.


> If you are afraid of your car...

I'm not afraid of MY car. I'm afraid of owning a car where I'm literally sitting on top of the battery. Say what you will about ICE's, but my gas tank is comparatively far away from me in comparison to EVs under-chassis battery designs.

Design a better battery where that removes this risk and I'll consider it, until then I'm sticking to my ICE.


Lithium batteries are dangerous in a way gasoline tanks are not: while a punctured tank (say, due to a unlucky collision with a piece of debris or a crash) is dangerous, it does not guarantee a fire or explosion. A punctured lithium cell will almost always burn.

There are also more ways to screw up a battery. Overcharging, manufacturing defects, and so forth. A gas tank is literally a chunk of cast metal with a pump in it.

Additionally, metal fires are severely hard to fight. Gas fires can be extinguished in the usual ways, but a self-oxidizing metal fire require special considerations, and that's if it can be reasonably extinguished at all. That isn't even mentioning the need to de–energize the battery before attempting a rescue.


Primary (non-rechargeable) lithium batteries contain metallic lithium, but all lithium ion batteries in vehicles contain lithium only in ionic form. Building rechargeable lithium batteries with lithium metal anodes is still in the research stage. The problem with fighting lithium ion vehicle fires is heat from battery self-discharge which can cause ignition and re-ignition of the flammable liquid electrolytes inside the batteries. That's one reason researchers are also pursuing solid state lithium ion batteries: to take out the flammable liquid electrolytes that current batteries need.


But ICE engines have had over 100 years of continuous testing and deployment on a mass scale. The risks and dangers are fairly well known now. EV's lag far behind that. Perhaps they should be deployed in smaller passenger vehicles before attempting trucks and buses.


They have been deployed in smaller passenger vehicles for well over 10 years now. Nissan Leaf... Tesla... etc.


Gasoline doesn’t burn. Gas+air mixture burns and the concentration of gas has to be surprisingly low for the reaction to work - 1 part gas for 14.7 parts air.

Batteries provide their own air and will burn submerged underwater, if they want to. The firefighting protocol is “Contain fire and wait, sometimes for days”. That’s why the containment cell is designed to be nigh impervious and fire is unlikely. But once a fire starts, good luck.


When was the last time you heard of a gasoline fire in a modern vehicle? Why is it that EV fires are so common?

> Other than being afraid of new technology.

... but then you resorted to ad hominem. Why would someone have to be "afraid" of new technology in order to have serious and legitimate concerns about it?

To help you out a bit, we also saw very bad lithium battery issues in laptops about ten years ago (just search youtube), to the point where airlines were seriously considering banning laptops and phones from being brought on board (and did ban one version of the Galaxy Note, IIRC). That was resolved, so it stands to reason that as EV improves, the risk of catastrophic fires will improve as well.

(Of course, those batteries were not being violently and physically damaged, so it's unknown whether software will be able to assist with accident-situations with an EV.)


According to the first statistic I found [1] there are about 180000 highway vehicle fires each year in the US, and in 26% of them the item that first ignited was "flammable or combustible liquid, gas filter or piping". So that's about 45000 gasoline fires a year in the US (if you don't count ones where the fire started somewhere else in the car). You just don't hear about them because they aren't newsworthy (precisely because there are so many).

Sadly the source states that they don't have good numbers on EVs to compare.

1: https://www.nfpa.org/-/media/Files/News-and-Research/Fire-st...


Some quick googling says tesla is ~70% [1] of the EV market and there is someone who claims to track every telsa fire [2] which has counts 97 fires since 2013. Compare that to 45k ICE vehicles fires every year and it appears that EVs are significantly less likely to catch fire.

I think if you live in one of the top 50 metro areas of the US and listen to local traffic news between June-August you'll probably hear about a traffic problem related to a car fire every few days or weeks. ICE vehicles fires are just so common we accept it and it's not reported unless especially gruesome.

1: https://electrek.co/2022/04/26/tesla-tsla-owns-75-percent-us...

2: https://www.tesla-fire.com/


> Compare that to 45k ICE vehicles fires every year and it appears that EVs are significantly less likely to catch fire.

You haven't provided enough information to make a comparison.

Googling some numbers, Tesla has sold 2MM cars, so taking that 97 number we get 0.00004 fires per Tesla.

US has 275MM cars, and (2022 - 2012) * 45000 = 450000, so we have 0.00163 fires per ICE car.

Conclusion: If those numbers are correct, Teslas are two orders of magnitude less likely to catch fire.


I bet if you control for vehicle age and economic status, EVs combust at the same rate as gasoline vehicles


"In 2017, 70% of the cars to catch fire were more than 10 years old."

https://housegrail.com/car-fire-statistics/#1_There_were_212...


Even if that's true (and your numbers do look to be similar to what I've seen), it's not relevant, because when a Tesla catches fire, it utterly immolates itself and everything around it. That is certainly not true for a gasoline fire once the fire engines roll up, to say nothing of a diesel fire, which are comparatively hard to start and easy to extinguish. It'd be far more informative to compare injuries and damages.


That's very fair. I've been in multiple cars that have caught on fire on the road. In my experience, ICE fires typically start in the engine bay. Hence why there's literally a firewall between you and the engine. A small handheld extinguisher can put them out easily, and I've done this myself as well.

I have no experience with EV fires, or how they start... but if it's under your ass in the battery pack, and no easy way to get an extinguisher in there... then by the time you notice, the fire may already be out of control.

I think that's what the big difference is going to be. EV fires will be less common, but will be way more crazy. That's why people will notice them much more.


> When was the last time you heard of a gasoline fire in a modern vehicle? Why is it that EV fires are so common?

Recently actually. An accident happened close to my place and one of the car caught fire. The driver died.

> Why is it that EV fires are so common?

How are they more common ? Do you have any statistics about it ?


> When was the last time you heard of a gasoline fire in a modern vehicle?

A fire in an ICE car 2 months ago shut down our local motorway for over 50 minutes during rush hour. A month prior to that, someone ran their ICE car off the road into a field; it caught fire and the driver died.

ICE vehicle fires are common. The difference is that EV vehicle fires are more widely reported upon. You see more stories about EV vehicle fires than ICE vehicle fires, so you think they happen more often.


>The difference is that EV vehicle fires are more widely reported upon

A clapped out POS or a crashed vehicle catching fire isn't newsworthy.

A vehicle bursting into flames without a good reason is.


> When was the last time you heard of a gasoline fire in a modern vehicle? Why is it that EV fires are so common?

What is their commonality, against ICE car fires? Are you subject to a recency/frequency bias in the news, or do you have some citable facts behind this? I see a LOT of news about EV fires, but few about the car fires I know happen because I drive past them. I suggest there is a reporting bias because of the topicality.


Pretty much everything you've outlined is an irrational fear.

ICEVs catch fire a lot, it's just not reported because it's not news.

https://www.nfpa.org/-/media/Files/News-and-Research/Fire-st...

> The others are range anxiety, energy storage portability and battery replacement costs.

Unless you frequently take long road trips, range anxiety isn't a thing for 200+ mile EVs. Batteries in EVs are currently warrantied for mileage far beyond the distances that most ICE owners drive their cars during it's usable life.

The horror stories you hear about people having to pay to replace batteries are usually because they failed to do something like have proper insurance.

> If I run out of gas on the side of the highway

Do you often run out of gas on the side of the highway and need AAA to deliver you gas? I have never in my life run out of gas.


> If your EV runs out of juice, you have to have it towed to a charging station.

Maybe that's the situation near you currently, but as EVs get more popular, these services will as well. It's just inevitable.

https://thedriven.io/2022/02/01/melbourne-start-up-launches-...


I'm sure AA vehicles will - if they already aren't - be supplied with a generator to put some juice back into electric vehicles on the roadside. Probably lighter, more compact, and less hassle than carrying around spare batteries.


It's gonna need to be a huge generator, or else they're gonna be sitting there all day. If you watch Long Way Up... take a look at the huge diesel trucks they need to have just to put the generator on the back to charge up the motorcycles.


The AA vehicles will likely be soon be EVs themselves, and allow sharing their own battery charge, just as some existing EV cars do.


(I'm not a driver, but I learned about this in German driving school)

> If I run out of gas on the side of the highway, I call AAA and they can deliver me a couple of gallons of gas or I can walk to a gas station. If your EV runs out of juice, you have to have it towed to a charging station.

AFAICT, if your diesel car runs out of fuel (completely), it also needs to get towed, maybe even to a garage to get serviced.


Fuel injectors, filters, and pumps in unleaded cars can also be damaged when the vehicle runs out of gas. I believe fuel injectors are always damaged when run dry but not necessarily to the point of failure.


AAA has offered mobile charging for electric vehicles for over 10 years.

https://www.caranddriver.com/news/a15346575/placebo-on-wheel...


And they retired the program sometime in 2019.


> I have no interest in sitting atop of a napalm bomb while zipping around town.

This is ironic considering ICE cars have a large reservoir of the primary ingredient in napalm. And with every new technology there is always a ramping phase. Prior to gas stations ICE cars would have the same range anxiety issues. They needed to find a pharmacy to refuel [0].

I've never understood the range anxiety. An EV only needs electricity to recharge. If there is a power outlet available anywhere you have a charge source. It might not be fast or pretty but its far less overhead than standing up a gas station in the middle of nowhere.

[0] https://en.wikipedia.org/wiki/Bertha_Benz


> sitting atop of a napalm bomb while zipping around town.

you do know what napalm is made of right?

petrol is really really nasty flammable shit. crashed cars catch fire, a lot.


> As much progress has been made in EVs, I have no interest in sitting atop of a napalm bomb while zipping around town.

That is literally what you are doing with gasoline car. And fuel being much more energy dense than a battery, it is actually more dangerous. Car burning was a thing way before EVs.




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