[HN Gopher] After bus fire, CT pulls electric fleet from service
___________________________________________________________________
After bus fire, CT pulls electric fleet from service
Author : starkd
Score : 52 points
Date : 2022-07-26 14:07 UTC (8 hours ago)
(HTM) web link (www.ctinsider.com)
(TXT) w3m dump (www.ctinsider.com)
| throwaway1777 wrote:
| How much emissions did that release compared to running a petrol
| bus?
| MafellUser wrote:
| Similar to a burning petrol bus.
| chernevik wrote:
| Which happens how often?
| MichaelCollins wrote:
| 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.
| billyo wrote:
| We need more electric trolley busses. This whole battery nonsense
| is ridiculous
| sleepybrett wrote:
| 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.
| olyjohn wrote:
| 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.
| tapoxi wrote:
| 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.
| billyo wrote:
| We need more electric trolley busses. These battery powered ones
| are nonsense
| akgerber wrote:
| Modern trolleybuses with in-motion charging, like Dayton's
| latest models, will still have substantial batteries for off-
| wire operation.
| RC_ITR wrote:
| Yeah but a city like sf has run those for decades very
| safely.
| sofixa wrote:
| Even then, a much lower capacity is required if the trolley
| bus will spend the majority of it's lifecycle on a catenary.
| KennyBlanken wrote:
| 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.
| sofixa wrote:
| 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.
| dangle1 wrote:
| 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...
| SigmundA wrote:
| 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.
| atlasunshrugged wrote:
| 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
| DoingIsLearning wrote:
| > 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.
| bdamm wrote:
| 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.)
| KennyBlanken wrote:
| 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.
| KennyBlanken wrote:
| > 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._
| nathanaldensr wrote:
| 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).
| quartesixte wrote:
| Add to the fact that the fuel is Lithium and you're in for a
| badddddd time
| kwhitefoot wrote:
| 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.
| bragr wrote:
| 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.
| DoneWithAllThat wrote:
| Please don't leave us in suspense: what are these tools and
| agents? Got a link?
| marcosdumay wrote:
| 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.
| bragr wrote:
| 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...
| KennyBlanken wrote:
| 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"
| [deleted]
| londons_explore wrote:
| 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.
| KennyBlanken wrote:
| > 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.
| londons_explore wrote:
| 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.
| KaiserPro wrote:
| 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)
| londons_explore wrote:
| 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.
| kayodelycaon wrote:
| How well do these safety feature survive 2,000+oF fire
| burning next to them?
| dymk wrote:
| there's a period of time between normal operation and
| 2000 degree fire where this could be detected
| marcosdumay wrote:
| Badly. How well does gasoline containers survive it?
|
| If you have a 2000degF 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.
| DoingIsLearning wrote:
| PCB solder will reflow at about 240degC or 470degF 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.
| Proven wrote:
| [deleted]
| woodruffw wrote:
| 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
| jdlshore wrote:
| 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.
| ZeroGravitas wrote:
| 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.
| dangerwill wrote:
| 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.
| mminer237 wrote:
| 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.
| woodruffw wrote:
| 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...
| googlryas wrote:
| 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.
| nomel wrote:
| 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.
| woodruffw wrote:
| 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
| nomel wrote:
| > Buses don't have inherently fixed routes
|
| In my city, they haven't changed the bus routes in several
| decades.
| woodruffw wrote:
| 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.
| DemocracyFTW2 wrote:
| 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...
| jeffbee wrote:
| 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.
| KaiserPro wrote:
| 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.
| jeffbee wrote:
| 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.
| [deleted]
| absolutelynobo wrote:
| 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.
| jeffbee wrote:
| 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.
| absolutelynobo wrote:
| 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?
| jeffbee wrote:
| 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
| absolutelynobo wrote:
| 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.
| throwaway0a5e wrote:
| 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.
| [deleted]
| txsoftwaredev wrote:
| A bus is only better if it is full of passengers, which is not
| always the case.
| velcrohacker wrote:
| 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?
| dumpsterlid wrote:
| 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.
| pineconebutt wrote:
| tantar wrote:
| 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
| beams_of_light wrote:
| 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?
| tantar wrote:
| 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).
| draw_down wrote:
| drooby wrote:
| > 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.
| novantadue wrote:
| This happened in China as well with a domino effect: 5 buses
| total https://newsasiatoday.com/electric-bus-china-caught-fire/
| ShakataGaNai wrote:
| 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...
| starkd wrote:
| 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.
| crinkletoes wrote:
| Shooting the battery pack won't cause the pack to do anything
| quickly. People would still have plenty of time to get out.
| velcrohacker wrote:
| Umm, it did. In CT. Last month. https://archive.ph/FZ2wv
| teawrecks wrote:
| 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?
| nomel wrote:
| 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.
| teawrecks wrote:
| 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.
| ceeplusplus wrote:
| 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.
| crinkletoes wrote:
| 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.
| mlyle wrote:
| > 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.
| kazinator wrote:
| Why don't we pull diesel bus fleets off the road whenever there
| is a diesel bus fire?
| GiorgioG wrote:
| 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.
| maeln wrote:
| > 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.
| ShakataGaNai wrote:
| 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.
| [deleted]
| starkd wrote:
| 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.
| olyjohn wrote:
| They have been deployed in smaller passenger vehicles for
| well over 10 years now. Nissan Leaf... Tesla... etc.
| Karunamon wrote:
| 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.
| philipkglass wrote:
| 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.
| throwaway0a5e wrote:
| 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.
| GiorgioG wrote:
| If this (one of many) example doesn't scare you, well then
| you're braver than I am: https://youtu.be/sAQlLu5ttOk?t=77
| mrguyorama wrote:
| 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.
| GiorgioG wrote:
| > 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.
| Cthulhu_ wrote:
| 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.
| chernevik wrote:
| When was the last recall of a gasoline fueled car for
| spontaneous combustion?
| MichaelCollins wrote:
| 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._
| Swizec wrote:
| 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.
| gunapologist99 wrote:
| 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.)
| ggm wrote:
| > 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.
| maeln wrote:
| > 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 ?
| aaronmdjones wrote:
| > 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.
| throwaway0a5e wrote:
| >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.
| wongarsu wrote:
| 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...
| jotux wrote:
| 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/
| olyjohn wrote:
| 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.
| Cpoll wrote:
| > 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.
| mrguyorama wrote:
| I bet if you control for vehicle age and economic status,
| EVs combust at the same rate as gasoline vehicles
| GiorgioG wrote:
| "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...
| gunapologist99 wrote:
| 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.
| viraptor wrote:
| > 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-...
| Cthulhu_ wrote:
| 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.
| olyjohn wrote:
| 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.
| ZeroGravitas wrote:
| The AA vehicles will likely be soon be EVs themselves, and
| allow sharing their own battery charge, just as some
| existing EV cars do.
| cptskippy wrote:
| 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.
| ThePadawan wrote:
| (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.
| cptskippy wrote:
| 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.
| donarb wrote:
| AAA has offered mobile charging for electric vehicles for over
| 10 years.
|
| https://www.caranddriver.com/news/a15346575/placebo-on-wheel...
| GiorgioG wrote:
| And they retired the program sometime in 2019.
| KaiserPro wrote:
| > 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.
| yardie wrote:
| > 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
| mikeytown2 wrote:
| 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
| chernevik wrote:
| > "they emit no emissions and they last longer"
|
| Not when they spontaneously combust they don't
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