NYC officials say they can't find EV garbage trucks powerful enough to plow snow • Hacker News Board

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#551

Post by LeifCarrotson » Thu, Jan 05, 2023, 6:50 PM UTC

postalrat wrote: post #539

LeifCarrotson wrote: post #341

Earlier quoted context omitted.

As an industrial EE dealing with hydraulics of much larger scales than those on a garbage truck, those other functions do not require significant power to operate when compared to actually accelerating the vehicle and cargo up to speed (and then slamming on the brakes/regen again for the next stop). The engines in diesel garbage trucks often run at idle when those hydraulics are working, lifting a 100 kg residential…

How about compacting the trash in the truck?

Assuming a 100mm bore cylinder with a 1.5m stroke (~10L volume), operating at 150 bar, with a stroke time of 1 minute, the power required is:

Power in kW = Pressure in bar * Flow in liters per minute / 600

2.5 kW = 150 bar * 10 l/min / 600

or a little more than 3 horsepower. That gives you about 15 tons of force. Maybe the trucks use two cylinders, one on each side, so double it? Plus 10% for pump inefficiencies, and 5% for electric motor inefficiencies (200% for diesel-to-kinetic losses)?

Still negligible compared to accelerating a huge steel box plus dozens of tons of trash to roadway speeds 1000 times a day.

Looking up some existing PTOs and pumps on munciepower.com, it looks like typical refuse systems are provisioned with PTOs and pumps rated for on the order of 10-50 kW, and diesel "prime movers" of 200-400 kW.

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#552

Post by jacquesm » Thu, Jan 05, 2023, 7:04 PM UTC

Robotbeat wrote: post #549

jacquesm wrote: post #516

Earlier quoted context omitted.

Yes, it certainly looks like a very clever solution. I know they tried the same thing with a flywheel based bus but that ultimately did not work out. Let's see how this works in practice.

It helps that batteries have literally two orders of magnitude greater range than an old school flywheel.

Yes, definitely, they are trialing this in Arnhem, I'll go have a look at it to see how it is all put together. By the looks of it they take a 'normal' trolley bus, remove diesel engine + tank + associated bits and pieces then put a battery in the spot where the tank used to be, and a bunch of electronics (regulator/inverter/charger) to create a voltage high enough to run the normal bus hardware of and to recharge the battery when the bus is connected to the overhead grid.

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#553

Post by kennend3 » Thu, Jan 05, 2023, 7:43 PM UTC

cogman10 wrote: post #382

sethhochberg wrote: post #336

There's a lot of discussion here, but I haven't seen anyone link this slide deck which (albeit a couple of years old) does a great job describing DSNY's efforts to electrify and some of their results with pilot programs: https://dsny.cityofnewyork.us/wp-content/uploads/2021/11/DSN... A lot of the things being proposed as solutions by posters here are already being tried in the real world. They're not running long-dis…

> We found that they could not plow the snow effectively – they basically conked out after four hours. We need them to go 12 hours This doesn't sound like they are trying to do short routes or fast charging stations. Rather, it sounds like they want to run their EV plows like they run their regular plows. The majority of LI batteries can be recharged in 1 hour with enough juice. Even if you say "well, it's a truck, s…

> The solution is really quiet simple, recharge the trucks and buy a few more to account for the fact that you have to recharge an hour for every 4 in operation. Stop trying to run your trucks for 12 hours straight.

I had to re-read this twice to make sure i wasnt misreading something.

The "simple" solution is to redesign the entire system, buy more vehicles, hire more drivers, etc because you are "pro electric" and electric vehicles cant perform the job?

Here's an idea.. Diesel vehicles are built to run 24 hours a day, and this is why they have large fuel tanks and heavy duty engines. Perhaps EV should be built to run 12 hours a day as well?

if the EV cant compete, then don't use it for this use case.

why should they "stop trying to run your trucks 12 hours a day" when they have done this for DECADES?

you make it sound like this 12 hour day is the problem, it is not, it is the EV's failure to keep up that is the issue.

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#554

Post by kennend3 » Thu, Jan 05, 2023, 7:55 PM UTC

cogman10 wrote: post #443

mike_d wrote: post #428

Earlier quoted context omitted.

What if we had some type of fluid that carried potential energy that we could quickly pour into a giant tank on the trucks? Some things will just never go electric. Like fire trucks, ambulances, tow trucks, power company trucks, etc. that have to be able to function for weeks at a time in a grid down situation. Dead dinosaurs are the best answer for some problems, just not every car on the road.

> fire trucks Would be excellent EVs. They have super low millage and you'd not have to worry about things like stagnant fuel. > ambulances Generally low mileage vehicles, no idea why you'd not be able to use them as EVs. > tow trucks Perhaps the only one that would be bad given the amount of power required to tow a vehicle. > power company trucks Excellent option for EVs because they almost never haul equipment and…

> Would be excellent EVs. They have super low millage and you'd not have to worry about things like stagnant fuel.

There is no "/s" so it is hard to tell if you are being sarcastic or not. Assuming you are not... EV's make TERRIBLE fire trucks.

How long does it take to fuel a fire truck? How long to recharge one?

You are blissfully unaware of how fire trucks work. Many are also diesel pumps, they arrive at fires and the truck itself is a massive water pump. Tell us, how many hours can a EV drive the water pump for? The diesel version can probably run for several days if needed.

My brother is a firefighter, they are AFRAID of electric vehicle fires because well.. Something about electricity + water?

If i call 911, i expect a fire truck to arrive, not some BS about how they had a power failure and their rechargeable truck isn't working.

PS - Stagnant fuel isn't a real thing. Fire trucks are generally very well maintained, they are expensive, they are essential life saving machines. They don't just sit somewhere forgotten and have their fuel go "bad".

They are driven almost daily because firefighters are expected to know their area and so they drive around to see where hydrants are, look at new subdivisions and sometimes simply to make sure it runs property.

They also have detailed logbooks and are inspected a LOT.

>Generators are a thing that pretty much every one of these services will have. Because you can't have a fire station, EMT dispatch, etc go dark because of a grid down situation.

> And, consider this when thinking of a "grid down" situation. How do you pump fuel if the grid is down?

First.. Fire stations use batteries then generators.

Second, you point out they have generators.. wouldn't that be used to transfer fuel answering your own question?

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#555

Post by kennend3 » Thu, Jan 05, 2023, 8:03 PM UTC

bayindirh wrote: post #536

cogman10 wrote: post #443

Earlier quoted context omitted.

> fire trucks Would be excellent EVs. They have super low millage and you'd not have to worry about things like stagnant fuel. > ambulances Generally low mileage vehicles, no idea why you'd not be able to use them as EVs. > tow trucks Perhaps the only one that would be bad given the amount of power required to tow a vehicle. > power company trucks Excellent option for EVs because they almost never haul equipment and…

> ambulances [are] Generally low mileage vehicles, no idea why you'd not be able to use them as EVs. Because they are neither low mileage and the medical equipment behind needs power. You never want your battery to go flat in an ambulance and lose the mobility and life support at the same time. Also, they're used the way EVs hate most. Accelerate and decelerate constantly while trying to plow through traffic in city…

> I wouldn't want an inextinguishable box of lithium near something hot like a fire. Would you?

This.

My brother is a captain for a fire department. I visited the hall many times with him and found the station design odd. He told me it is built that way because there have been cases of fire trucks being too close to major fires, and the truck catching fire back at the station.

The station has "blast doors" that automatically close if the bay is on fire to protect the rest of the station. (sounds funny right.. fire halls catching fire??)

Not sure they would want a "flammable metals" fire in their bay.

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#556

Post by kennend3 » Thu, Jan 05, 2023, 8:08 PM UTC

cogman10 wrote: post #445

CPLX wrote: post #413

Earlier quoted context omitted.

Plus the drivers. Plus the fact that the streets are full of snow at the time which in addition to making the whole thing timely complicates things logistically quite a bit.

You don't need more drivers, just more trucks. A driver brings a truck to a charge location, grabs a truck that's been charging. Easy peasy. There's no reason to have drivers wait for the trucks to fully charge.

> A driver brings a truck to a charge location, grabs a truck that's been charging. Easy peasy.

Tell us you have no idea how much a garbage truck costs without telling us.

Must be nice to have a few million dollars in "spare" trucks lying around. Garbage trucks can run up to $400,000 EACH.

This is how you propose to waste taxpayer money, by replacing perfectly working trucks with EV's where you need to buy "spare" ones as well?

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#557

Post by angry_octet » Thu, Jan 05, 2023, 9:44 PM UTC

jollyllama wrote: post #547

angry_octet wrote: post #521

Earlier quoted context omitted.

If they had even a 10th of the organisation of Montreal they wouldn't have such problems. They're relying on the wrong tools. https://theprepared.org/features-feed/montreal-snow And this article makes it seem like a huge investment, but in reality these workers do other jobs most of the year, in construction, roadworks, gardening, waste management, etc. It really seems like NY are wedded to their old ways -- somethin…

Nice link. The first step is informing citizens when their streets will be cleared. In dense, downtown neighborhoods, most people park on the street and their cars need to move. No parking signs get installed block by block and notifications go out through the city-maintained snow removal app, InfoNeige (equivalent to InfoSnow in English). Municipal lots are opened up with free parking, and as one final warning, tow…

The 'your car is about to be towed' siren is astonishingly loud, an inevitably at 4AM. It saves them time but jeebus.

https://youtu.be/WvN-HLf_ekM

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#558

Post by andbberger » Thu, Jan 05, 2023, 9:48 PM UTC

sandos wrote: post #537

andbberger wrote: post #310

Earlier quoted context omitted.

one of the worst decisions the MBTA has ever made. battery buses are inferior to trolleybuses in pretty much every scenario, but especially winter. the battery buses they're replacing the trolleybuses with have diesel heaters to keep the batteries warm.

Wow, why not ethanol heaters or something similar? Volvo did that several years ago in one of their first EV buses.

why not leave the wires up

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#559

Post by r00fus » Thu, Jan 05, 2023, 9:55 PM UTC

samspenc wrote: post #128

tapoxi wrote: post #101

Earlier quoted context omitted.

Here in Massachusetts we just removed our streetcar power lines (MBTA 71 and 73 trolleybus) because the wires needed to be removed during construction. This might be a logistical issue for NYC. https://www.mbta.com/news/2022-01-27/beginning-march-2022-mb...

Yeah having street car power lines can be a nightmare in densely crowded cities with a lot of pedestrian traffic and tightly packed buildings. It would be a nightmare to implement in a place like New York City, and I'm not surprised that cities that have them are slowly removing them. Don't get me wrong, I think they are a great solution electrically and for efficiency / sustainability, but require an enormous geogra…

So just to be clear they shouldn't cost anywhere near as much as a subway or even tram rails. With a decent bit of battery on the vehicle, you could even have < 100% coverage and have outage resiliency.

Re: NYC officials say they can't find EV garbage trucks powerful enough to plow snow

#560

Post by colechristensen » Thu, Jan 05, 2023, 10:00 PM UTC

dekhn wrote: post #165

colechristensen wrote: post #66

Earlier quoted context omitted.

Eh, your car will run a little shitty with the old gas, leaving an engine without running it for extended periods can cause somewhat faster corrosion depending on your environment, and old gas can increase things like various gunk getting deposited around your engine. All in all, a mild shortening of the life of your engine and perhaps triggering some maintenance sooner than otherwise. Realistically, not much. The pe…

Thank you! This was my conclusion as well: there's an effect, it's small, and was probably much larger 30 years ago. I also only have the oil changed every 10K miles which horrifies my friends.

But seriously, change your oil more often. There’s some simple chemistry going on where the oil gets worse at being oil over time and you get extra engine wear, and if you’re not paying attention and burning oil your engine can get bricked in seconds.

I only change my oil every 10k miles (or really 6-8k most often) but in an engine and with an oil specifically rated for such. Your jiffylube 5w30 (if that’s what you’re doing, if you’ve actually got an oil rated for 10k you’re fine) isn’t going to do great. It’s maybe 50-50 whether bad oil change schedule will be the thing that kills your car.