After bus fire, CT pulls electric fleet from service • Hacker News Board

Re: After bus fire, CT pulls electric fleet from service

#31

Post by jeffbee » Tue, Jul 26, 2022, 2:57 PM UTC

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.

Re: After bus fire, CT pulls electric fleet from service

#32

Post by DoingIsLearning » Tue, Jul 26, 2022, 2:57 PM UTC

kayodelycaon wrote: post #22

londons_explore wrote: post #8

Earlier quoted context omitted.

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 on…

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.

Re: After bus fire, CT pulls electric fleet from service

#33

Post by akgerber » Tue, Jul 26, 2022, 2:59 PM UTC

billyo wrote: post #28

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.

Re: After bus fire, CT pulls electric fleet from service

#34

Post by Proven » Tue, Jul 26, 2022, 3:01 PM UTC

atlasunshrugged wrote: post #2

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…

No post body was provided.

Re: After bus fire, CT pulls electric fleet from service

#35

Post by yardie » Tue, Jul 26, 2022, 3:04 PM UTC

GiorgioG wrote: post #7

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…

> 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

Re: After bus fire, CT pulls electric fleet from service

#36

Post by dumpsterlid » Tue, Jul 26, 2022, 3:04 PM UTC

jeffbee wrote: post #31

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 a…

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.

Re: After bus fire, CT pulls electric fleet from service

#37

Post by mikeytown2 » Tue, Jul 26, 2022, 3:04 PM UTC

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

Re: After bus fire, CT pulls electric fleet from service

#38

Post by wongarsu » Tue, Jul 26, 2022, 3:05 PM UTC

gunapologist99 wrote: post #23

ShakataGaNai wrote: post #12

Earlier quoted context omitted.

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…

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 sea…

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...

Re: After bus fire, CT pulls electric fleet from service

#39

Post by GiorgioG » Tue, Jul 26, 2022, 3:05 PM UTC

throwaway0a5e wrote: post #18

ShakataGaNai wrote: post #12

Earlier quoted context omitted.

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…

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

Re: After bus fire, CT pulls electric fleet from service

#40

Post by ggm » Tue, Jul 26, 2022, 3:06 PM UTC

gunapologist99 wrote: post #23

ShakataGaNai wrote: post #12

Earlier quoted context omitted.

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…

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 sea…

> 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.