[HN Gopher] Electric buses withdrawn in south London after fire
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Electric buses withdrawn in south London after fire
Author : antongribok
Score : 43 points
Date : 2024-01-14 17:26 UTC (5 hours ago)
(HTM) web link (www.bbc.com)
(TXT) w3m dump (www.bbc.com)
| verisimi wrote:
| Why the big fuss? Fires happen occasionally. Is there something
| about the fire that was avoidable? There are really no details
| given - a real non-story.
|
| Perhaps this part of a PR campaign to signal how government takes
| this sort of thing very seriously?
| xeromal wrote:
| Your second point is probably the correct point, but hopefully
| we find out more with time.
|
| Battery fires are actually very hard to tackle so my guess is
| that these busses were built to avoid catching on fire as much
| as possible so when one does happen, they need to investigate
| to make sure there isn't a major design flaw.
| Symbiote wrote:
| It seems to be part of the current "culture war" in Britain --
| at least judging by the promoted Facebook posts I see.
|
| Over half of London's buses are electric (11%) or hybrid (44%)
| so it's not surprising that fires are now affecting these.
| graemep wrote:
| Promoted FB posts are a very bad measure of what is
| happening. They are designed to provoke people and get
| reactions - it is all about engagement.
|
| I do not know what the motive is (some way of making money no
| doubt) but it is clear to me that these are mostly just
| trying to get comments and reactions.
|
| I strongly suspect a lot of what I see on FB is not even
| human written - lots of jokes that do not quite make sense,
| minor variations on things I have seen before that also do
| not quire make sense.
| Symbiote wrote:
| There's also reporting like "Officials today launched an
| investigation after one of Sadiq Khan's electric buses
| exploded during today's rush hour". [1]
|
| "A huge blast ripped off the back of an Optare Metrodecker
| 1050 bus"... yet the picture shows the back of the bus is
| intact. [2]
|
| Daily Mail nonsense like this was enough to influence the
| Uxbridge byelection (over LTNs), but I'll admit I'm too far
| away from Britain to know the situation.
|
| [1]
| https://www.dailymail.co.uk/news/article-12950765/London-
| ele...
|
| [2] https://www.dailymail.co.uk/news/article-12955781/Wimbl
| edon-...
| rsynnott wrote:
| It seems like a _bit_ of a non-story, absent any other info;
| bus fires are more common than you might think.
| walthamstow wrote:
| This article is in the BBC's local news section for London.
| It's a run-of-the-mill public transport local news story. It's
| not national news. Why it has been posted here, I don't know.
| antongribok wrote:
| I posted this and can answer your question.
|
| I don't live in UK, and don't generally read the local news
| section of BBC, so this was displayed on the side when I was
| reading a story about the volcanic activity in Iceland.
|
| I clicked on the story, because it was about electric busses,
| a subject I'm interested in, since we don't have any where I
| live.
|
| After clicking on the story, I was a bit disappointed with
| the lack of detail.
|
| I decided to post here, because I figured if it got any
| traction, someone on here would post a bit more detail.
|
| The top comment on here currently is exactly what I was
| hoping to see, and I'm glad I posted the story.
| vidarh wrote:
| They've withdrawn the electric buses on one specific route,
| which a later paragraph suggests is a specific type, while
| figuring out if there's a specific issue. It's posted in a
| regional sub-section for London rather than in their national
| news. That doesn't sound like a big fuss to me.
| CraigJPerry wrote:
| I saw this on the BBC the other day, it made me go look up how
| many bus fires there are.
|
| 242 over the past couple of years (although it seems these are
| mostly diesel or hybrid rather than battery), there's reasonable
| detail in the summaries further down the page by cause:
| https://www.gov.uk/government/publications/investigation-int...
|
| I couldn't find a way to estimate fires per miles driven.
|
| It also doesn't include all bus fires, only those reported to the
| DVSA. London Fire Brigade reports a bunch more in their
| publication.
| a1o wrote:
| It would be interesting to see if there was some weighted way
| to compare bus fires in non-electric ones vs electric ones. To
| check if either have bigger probability for the fire being a
| bigger issue.
| 4wsn wrote:
| I don't really see a link between electric bus fires and diesel
| fires. The safety issue is that electric vehicle fires are far
| more difficult to control than their combustion counterparts.
|
| "Electric Vehicle Fire" by "South Metro Fire Rescue Centennial,
| Colorado"
|
| https://youtu.be/itGeAq9rBeY
| AtlasBarfed wrote:
| What was the chemistry of the battery? I'm guessing it wasn't
| LFP, but then again I've heard that LFP isn't quite as fire
| bulletproof as it was advertised.
| hgomersall wrote:
| Where have you heard that? I've seen videos of people actually
| sinking axes into LFP cells which just vent a bit compared to
| say NMC which burst into flames.
| rightbyte wrote:
| I have never heard that LFP would be fire safe. Just safer
| compared to other lithium cell types.
| TheLoafOfBread wrote:
| Correct. That energy stored in the battery needs to go
| somewhere. Failing fully charged LFP is no less dangerous
| than any other chemistry.
| ianburrell wrote:
| The electrolyte in lithium ion batteries is very flammable.
| It combusts on contact to air which is why batteries if
| punctured. LiFePO4 batteries don't have super flammable
| electrolyte; they can burn but not easily and violently.
| avianlyric wrote:
| It's is less dangerous, because LFP has lower energy
| density that other lithium chemistries so which means
| either less energy to dissipate per kg of battery, or more
| surface area to dissipate the energy per joule.
|
| Also LFPs don't contain components with negative
| temperature coefficients of resistance (I.e. stuff that
| gets more conducive as it heats up), which reduces the risk
| of thermal runaway because LFPs increase their resistance
| as they get hot, reducing their max output power. Rather
| other chemistries that reduce resistance as they get hot,
| increasing their output power.
| janice1999 wrote:
| Edit: See comment below. The first fire was a fully electric
| bus, not a hybrid.
|
| > "The vehicle utilises a 32kWh capacity energy storage system,
| comprising third generation lithium nickel manganese cobalt
| battery technology"
|
| I think it might be this hybrid but I could not find a
| confirmation [0].
|
| [0] https://www.alexander-dennis.com/alexander-dennis-
| enviro400e...
| rsynnott wrote:
| Almost certainly one of these:
| https://en.wikipedia.org/wiki/Switch_Metrodecker , based on
| the details in the story. Full battery bus, not a hybrid.
| Been around for 10 years, so probably unlikely to be LFP.
| janice1999 wrote:
| Thanks. I haven't heard of Switch Mobility before.
| vidarh wrote:
| You're likely right. Here's a site that lists the vehicles
| used on the specific route mentioned a few days ago [1] and
| now [2]. All the ones starting Me appears to be
| Metrodecker's (click through the vehicle number). Notice
| how they've been replaced by "SE" (which appears to be ADL
| Environ200's) and others.
|
| https://bustimes.org/services/200-raynes-park-wimbledon-
| mitc...
|
| https://bustimes.org/services/200-raynes-park-wimbledon-
| mitc...
| michaelt wrote:
| The article is actually about _two_ bus fires - one in west
| london, south of the thames:
|
| _> a double-decker caught fire on Thursday [...] The fire
| started during the morning rush hour in Wimbledon [...] the
| operator, London General - a subsidiary of Go-Ahead London -
| and the bus manufacturer, Switch_
|
| And also one a day later, in east london, just north of the
| thames:
|
| _> On Friday, a hybrid double-decker bus was destroyed in a
| fire [...] in North Woolwich. [...] the operator, Go-Ahead,
| and the manufacturer, Alexander Dennis [...] we have no
| reason to suspect that this fire on a hybrid bus was linked
| to an earlier incident on an electric bus_
| christkv wrote:
| Oslo in Norway had massive problems due to the cold affecting the
| amount of charge the buses would hold as well as the charge speed
| leaving them unable to recharge them fully over night.
| Phlarp wrote:
| A universal problem for all EVs in cold climates
| rightbyte wrote:
| The temperature does not affect to charge stored in the
| batteries, right? However, you have to use the battery to heat
| itself as well as heat the bus (unless you got diesel heater or
| something for the cabin).
| withinboredom wrote:
| It's pretty well known (in industries that use batteries)
| that temperature affects the capacity of batteries.
| pxeboot wrote:
| Batteries produce electricity through a chemical reaction.
| When it is colder, that reaction creates less electricity.
|
| If you fully charge a battery, freeze it, then warm it back
| up, it will still be close to fully charged.
| avianlyric wrote:
| It'll impact the usable charge because the colder temps will
| decrease the ability of the battery to produce high currents.
| Effectively setting the floor for a "useful" charge level
| higher. Below that useful level, current supply is too low to
| power whatever it is you're powering.
| AnthonyMouse wrote:
| Oslo can't have been surprised by the existence of cold
| weather. Did they not contemplate any countermeasures, like
| heaters at the charging location or better insulating the
| batteries so the heat from discharging them and then recharging
| through regenerative braking keeps them warmer?
| NullPrefix wrote:
| Bus developers probably weren't based in Oslo
| AnthonyMouse wrote:
| Toyota isn't based in Oslo either but they know how to make
| a vehicle that runs there, and the companies that don't
| generally don't do a lot of business there.
| incrudible wrote:
| Electric buses in Oslo Norway (of all places) is a
| dictate of politics, not practicality. The people
| implementing the politics were likely warning about such
| oversights, but were rebuffed. They will gladly see it
| all fail, so that they may say: We told you so.
| jrmg wrote:
| This appears to be an exaggeration that's making its way around
| less scrupulous news sources. From https://www.euronews.com/my-
| europe/2023/12/30/was-oslo-paral... :
|
| _a spokesperson called the allegations "an extreme
| exaggeration... We cancelled, on average, between 50 and 100
| departures, out of more than 4,000 daily departures, for a few
| days."
|
| The company did however admit they had a few "challenges with
| the range of the buses being shorter in cold weather."
|
| "We solved this by changing the charging shifts. And also by
| fixing the charging infrastructure."
|
| Ruter [the bus operating company] claims the issues have since
| been fixed and the fleet of electric buses continues to run as
| usual._
| christkv wrote:
| That not right at all. Norwegian news say something very
| different and is probably more reliable.
|
| https://www.nrk.no/stor-oslo/kaller-inn-byrad-i-oslo-pa-
| grun....
|
| Reached 1000 cancelations at the worst in a single day it
| seems.
|
| They managed to resume traffic by using emergency diesel
| replacement buses.
| MrEd wrote:
| That's one reason to not switch to EVs. But muuuh local
| emissions free...
| rokkitmensch wrote:
| Tail risk is simply outright difficult to get through folks'
| head.
| ilikeitdark wrote:
| We have had quite a few "unexplained" electric and hybrid bus
| fires here in Barcelona the last few years.
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(page generated 2024-01-14 23:02 UTC)