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After bus fire, CT pulls electric fleet from service

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

#141

Post by fy20 »

mlyle wrote: post #74
ceeplusplus wrote: post #73

Earlier quoted context omitted.

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.

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

#142

Post by weq »

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

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

#143

Post by KaiserPro »

jeffbee wrote: post #53
KaiserPro wrote: post #52

Earlier quoted context omitted.

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.

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

#144

Post by ZeroGravitas »

yellowapple wrote: post #137
ZeroGravitas wrote: post #105

Earlier quoted context omitted.

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 capab…

> 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.

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

#145

Post by syntheweave »

dangerwill wrote: post #101
jdlshore wrote: post #100

Earlier quoted context omitted.

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.

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.

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

#146

Post by ZeroGravitas »

woodruffw wrote: post #113
mminer237 wrote: post #109

Earlier quoted context omitted.

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…

> 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.

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

#147

Post by woodruffw »

ZeroGravitas wrote: post #146
woodruffw wrote: post #113

Earlier quoted context omitted.

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…

> 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 wi…

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.

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

#148

Post by nomel »

omg_ponies wrote: post #140
nomel wrote: post #131

Earlier quoted context omitted.

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'v…

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.

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