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| Massive EV cement truck fire: official 'explanation' versus the facts. |
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| EPAIII:
And ______ is going to pay the cost of replacing the dangerous lithium cells with these safer ones! On an expedited schedule, of course. Please fill in the blank. --- Quote from: thm_w on December 22, 2023, 01:05:00 am --- --- Quote from: EPAIII on December 21, 2023, 03:18:34 am ---That statistic may be true, but it sounds like it needs to be clarified. One thing I would ask about is just how big the fire events were. Perhaps I am wrong, but when a gas or diesel vehicle catches fire, it can be easily extinguished. I had a fire in my gas powered truck on a highway trip and was able to put it out with the small fire extinguisher that I carried. I even had time to pull over to the shoulder of the road, get out of the truck, open the hood, observe the fire, go into the trailer to get the extinguisher, return to the truck, and put the fire out. I did this myself, with a small extinguisher. And after it cooled down, I was able to drive the truck and trailer to the next exit where repairs were made. --- End quote --- You are giving an example which wouldn't even have been in the gas vehicle fire statistics, not the greatest example but OK. Your concerns should be resolved by having the appropriate tools for the fire department, sprinklers or other systems inside car parks to mitigate fire spread where possible. As mentioned above, as LFP gets wider adoption, spread will be less of an issue if at all. --- Quote ---In work by Willstrand et al., heat release rates (HRR) from full-scale fire tests performed in recent years with modern vehicles, including both ICEVs and BEVs was summarised. The compiled data showed a minor difference in the total energy released during the fire (total heat release) between ICEVs and BEVs. The total heat release for ICEVs range between 3.3 to 10 GJ and for BEV between 4.7 to 8.5 GJ. No difference in peak heat release rate or effective heat of combustion could be seen for the compared vehicles (Willstrand et al., 2020). --- End quote --- https://lashfire.eu/media/2022/09/2022-08_Facts_and_Myths.pdf --- Quote from: coppercone2 on December 21, 2023, 08:18:34 pm ---people need to try driving EV, their just better. gasoline is horse and buggy and feels like it! stretchy cars. I feel like its those people warning me against the first Lion power drills (mid 2000's makita), which ended up utterly kicking ass. In the early 2000's there was down right prosecution against my makita drill acquisiton. --- End quote --- Yeah but how many horse and buggy fires are there? Clearly the safest and more superior mode of transportation. --- End quote --- |
| vk6zgo:
--- Quote from: thm_w on December 22, 2023, 01:05:00 am --- --- Quote from: EPAIII on December 21, 2023, 03:18:34 am ---That statistic may be true, but it sounds like it needs to be clarified. One thing I would ask about is just how big the fire events were. Perhaps I am wrong, but when a gas or diesel vehicle catches fire, it can be easily extinguished. I had a fire in my gas powered truck on a highway trip and was able to put it out with the small fire extinguisher that I carried. I even had time to pull over to the shoulder of the road, get out of the truck, open the hood, observe the fire, go into the trailer to get the extinguisher, return to the truck, and put the fire out. I did this myself, with a small extinguisher. And after it cooled down, I was able to drive the truck and trailer to the next exit where repairs were made. --- End quote --- You are giving an example which wouldn't even have been in the gas vehicle fire statistics, not the greatest example but OK. Your concerns should be resolved by having the appropriate tools for the fire department, sprinklers or other systems inside car parks to mitigate fire spread where possible. As mentioned above, as LFP gets wider adoption, spread will be less of an issue if at all. --- Quote ---In work by Willstrand et al., heat release rates (HRR) from full-scale fire tests performed in recent years with modern vehicles, including both ICEVs and BEVs was summarised. The compiled data showed a minor difference in the total energy released during the fire (total heat release) between ICEVs and BEVs. The total heat release for ICEVs range between 3.3 to 10 GJ and for BEV between 4.7 to 8.5 GJ. No difference in peak heat release rate or effective heat of combustion could be seen for the compared vehicles (Willstrand et al., 2020). --- End quote --- https://lashfire.eu/media/2022/09/2022-08_Facts_and_Myths.pdf --- Quote from: coppercone2 on December 21, 2023, 08:18:34 pm ---people need to try driving EV, their just better. gasoline is horse and buggy and feels like it! stretchy cars. I feel like its those people warning me against the first Lion power drills (mid 2000's makita), which ended up utterly kicking ass. In the early 2000's there was down right prosecution against my makita drill acquisiton. --- End quote --- Yeah but how many horse and buggy fires are there? Clearly the safest and more superior mode of transportation. --- End quote --- Having been on the receiving end of very high-octane horse farts, I would definitely discourage anybody from lighting a cigarette while it is in full flow. |
| Gyro:
--- Quote from: EPAIII on December 22, 2023, 05:49:27 am ---Airport car park! Been there. They are one of the loneliest places in any city. I wonder just how many cars were either on fire or completely burned out BEFORE ANYONE even noticed there was a fire. ... If a battery fire can destroy 1500 vehicles in an airport car park... --- End quote --- This one was spotted almost immediately (while it was just a single car), it's a busy car park. People tried to fight it with available fire extinguishers before being forced to retreat. As previously detailed, it wasn't an EV, it was a Diesel. |
| vk6zgo:
--- Quote from: Gyro on December 22, 2023, 01:56:01 pm --- --- Quote from: EPAIII on December 22, 2023, 05:49:27 am ---Airport car park! Been there. They are one of the loneliest places in any city. I wonder just how many cars were either on fire or completely burned out BEFORE ANYONE even noticed there was a fire. ... If a battery fire can destroy 1500 vehicles in an airport car park... --- End quote --- This one was spotted almost immediately (while it was just a single car), it's a busy car park. People tried to fight it with available fire extinguishers before being forced to retreat. As previously detailed, it wasn't an EV, it was a Diesel. --- End quote --- There are a lot of false reports purporting to be about fires caused by EVs, & even misstating where the fire happened. There was a fire in a car storage yard here in Perth WA (with nary an EV in the yard) which appeared on the Internet as a whole lot of EVs on fire in China. Most of these things can be checked on Snopes, and are almost always BS. |
| tom66:
--- Quote from: EPAIII on December 22, 2023, 05:49:27 am ---If a battery fire can destroy 1500 vehicles in an airport car park, think what it could do in the lower floors of a tall office building. One of the 9-11 aircraft was said to carry 20,000 gallons of jet fuel, which was the actual weapon used by the terrorists to bring those building down. With 90% of 1500 autos, each having a partial tank of gasoline you could easily have that same 20,000 gallons of fuel. And access to such an office building's parking area would be far, far more difficult for the fire department. I don't think you can glibly say that when all the fire departments get the correct tool, the problem is solved. They must get to that FIRST EV in time to actually use that device before the fire spreads out of control. --- End quote --- Building designers aren't idiots. They know car park fires happen. They know that putting an office block on top of a car park that can burn presents additional risk. Depending on the use, the buildings are designed to withstand different fire durations. In the UK, a regular car park only needs to withstand fire for 15 minutes. That is, the fire can have spread to the next floor within 15 minutes. That sounds crazy at first, but think about it: car parks are wide, open spaces. Evacuation is easy. We care about humans. Cars can be replaced, people can't be. The fire doors and evacuation stairs have to withstand the fire for far longer, usually 60-90 minutes, giving sufficient time for fire fighters to stage an attack and search for anyone who could be trapped. It's notable in the car park fire in Liverpool, UK, in 2018, the car park was totally gutted, but the fire escapes were relatively untouched. There was only a bit of smoke damage, the fire doors had otherwise completely withstood the entire car park going up [1]. For something like a shopping mall, where there might be a populous retail area attached to a multistorey car park, the car park area is designed to contain the fire for as long as possible, with double fire-door systems linking the two (when you next visit one, see how they design this). The populated areas of the shopping mall can be evacuated quickly; the plans are well established. Units that have a large number of people, like a cinema, are placed away from the car park area (and will have their own fire escapes), as these will naturally take longer to evacuate. Fire alarm systems will be linked. The fire won't spread to the retail units for some time, but again, economic cost if it does, no lives lost, no big deal. Office blocks are more challenging, but usually a substantial concrete foundation barrier will exist between any underground car park and the busy office block. The office block itself will have normal evacuation procedures. If it's big enough it'll have things like backup generators to keep lifts going for evacuation. I'm sure some fire chiefs fret about fighting these fires, and sure, they're going to be a challenge, but battery-EVs don't make huge car park fires much worse. The majority of energy comes from the burning of the flammable interior and plastics, the battery might add fuel to the, er, fire, but it's really not that much energy compared to the rest of the car. Just on a fundamental physics level, a lithium-ion battery is nearly inert when fully discharged (this is why when transported, EVs are only charged to 10% or so). They can still burn, but much less ferociously. This tells us the energy released from a battery can't be much more than what it is charged up with. Maybe 0.5GJ worst case for some of the biggest SUV EVs. [1] https://www.bafsa.org.uk/wp-content/uploads/bsk-pdf-manager/2018/12/Merseyside-FRS-Car-Park-Report.pdf (page 41, 42, showing how good fire door design works) |
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