USPS is getting new trucks but only 10% are electric

[atxcyclist]

This is taken from a Tesla article on regenerative braking performance:

 

Quote

But as a practical matter, the kinetic energy of a slowly moving car is low enough that very little energy is put back into the battery as the car comes to a stop. In fact, the last little bit of slowing the vehicle down generates such a small amount of energy that it does not even cover the fixed losses in the inverter and motor.

https://www.tesla.com/blog/magic-tesla-roadster-regenerative-braking

[Bombastinator]

38 minutes ago, DeScruff said:

O RLY?

 

So what are you asking for the source on then?
Cause everyone is telling you "Start stop start stop" vs constant movement is less efficient and you ask "SOURCE!?"
I explain the physics on why you need more energy to start from 0mph (Which a mail truck does... constantly)- "Thats not the claim i'm asking source on!"

So what are you asking the source on? That a mail truck starts and stops every couple of feet? Or why "Start stop" is not as efficient as constant running?
 

Not all of them do that.  It depends on the route. Neighborhoods were put together at different time periods, and have different styles of mail box.  In my neighborhood the mail carrier drives up, parks, and delivers the mail on foot.  Other routes are rural with 

mailboxes in clusters a quarte mile or more apart.  It just varies a lot. 

[IkeaGnome]

On 2/26/2021 at 12:18 PM, poochyena said:

but it is.

 

lmao, what? Do people in rural areas not have electricity?
They do. Its literally just a one or two day job to add some extra connectors to usps hubs to garage or yards that the trucks are parked at. They'll have 12 hours to charge, they don't need advanced fast charging connectors.

 

That makes no sense. Thats the cheaper option, the more expensive option is to buy a gas truck and then upgrade it later.

You can literally drive from one side of Iowa to the other, 300 miles, on a single charge from tesla model 3

I think you're also forgetting cold temperatures. Give the graph on page 3 a look. Keep in mind our temps(Alaska) include South East which is usually a lot warmer in winter than the rest of the state. In Juneau it's 2C right now, but where I live it's -14C with windchill. -20 to -30C isn't uncommon where I live, and in places like Fairbanks and north of there, -40C with wind isn't uncommon. This is the main thing holding me back from getting an EV. There's not much for charging even in Anchorage. I'm 90 miles(140km) from Anchorage. Round trip that's 180 miles, or 280KM. With no stops in town for shopping. Just to the edge of town and back. Figure 15 miles or so just driving around with well planned stops, that's 105 miles(170 KM). Tesla has a 300ish mile range. At -20C you lose roughly 41.66%. Or a 124 mile range loss. Leaving 176 miles. Our trip leaves 71 miles of driving range. That's not a lot for "plan B", breakdowns on the highway staying warm etc. It's pushing it.

300 miles of range isn't always 300 miles of range.

https://www.nature.com/articles/s41467-018-04826-0.pdf?origin=ppub

They'd either have to custom make vehicles for up here or up the cost for nationwide vehicles to do an all EV rollout. 

[DeScruff]

8 minutes ago, dalekphalm said:

Let me try and clarify:

 

If you're running a gasoline car in stop and go traffic, like a mail truck, it gets horrible efficiency. And when you slow down, all you're doing is wearing down the brakes.

 

In an electric car, you also lose efficiency from start/stop. But you gain charge with regenerative braking. No, the regenerative braking doesn't fully make up for the starting again, but it does make up for a significant portion.

 

Someone said 64% above. So let's assume that every time they slow down, they regain 64% of that energy.

 

I think people are just making a lot of assumptions, and he's simply asking for proof.

That 64% comment was me, and my source was Tesla. That number is considered an ideal, since its just the wheel to battery then back to wheel efficency, and Tesla also states other factors do come into play.

To clarify myself: I am not saying Electric is worse then Gas. - On the contrary. Electric is likely significantly better than gas in a Mail truck scenario.
Why they aren't going a higher % electric out the gate might be a whole host of issues, from funding, to which vehicles need to be replaced asap and that likely over this 10 year contract that % being out of the factory electric will change since many long term contracts change numbers over time.

I dispute the 300 mile claim as a given, on the merits that:

1. The specs for the vehicle are not stated, no such claims were made public.
2. It is an assumption based on another vehicle.
3. The other vehicles estimated mileage is a more energy efficient use case, so even under the same specs, the battery usage (mileage) would be different (and likely have less mileage)

I did question if 300 miles was enough since I do know a mailtruck drives around a smaller area multiple times to get to every house. Knowing that I was unsure the exact miles a mail truck typically drives per day. However looking up and seeing the longest delivery route being a lil over half that (187.6 miles), then yes I acknowledge if these things could achieve 300 miles under their own usecase. It would be more then enough.

[Bombastinator]

Th postal service is a somewhat unique animal.  It isn’t exactly a non profit and it isn’t exactly a government utility. It’s run like a business.  They will likely have specific reasons for doing what they did. 

[dalekphalm]

4 minutes ago, DeScruff said:

That 64% comment was me, and my source was Tesla. That number is considered an ideal, since its just the wheel to battery then back to wheel efficency, and Tesla also states other factors do come into play.

Of course - realistically it will be less efficient when slower.

4 minutes ago, DeScruff said:

To clarify myself: I am not saying Electric is worse then Gas. - On the contrary. Electric is likely significantly better than gas in a Mail truck scenario.
Why they aren't going a higher % electric out the gate might be a whole host of issues, from funding, to which vehicles need to be replaced asap and that likely over this 10 year contract that % being out of the factory electric will change since many long term contracts change numbers over time.

I think we can almost entirely attribute funding to being the primary reason they're not doing more than 10% (as of the initial order).

4 minutes ago, DeScruff said:

I dispute the 300 mile claim as a given, on the merits that:

1. The specs for the vehicle are not stated, no such claims were made public.
2. It is an assumption based on another vehicle.
3. The other vehicles estimated mileage is a more energy efficient use case, so even under the same specs, the battery usage (mileage) would be different (and likely have less mileage)

The 300 mile was just an example of a readily achievable range for a production EV.

 

The real answer is that the NGDV will get exactly as much range as the USPS wants it to have. The tech exists to give it 1000 miles range if that's what they needed (you just put more batteries in - and yes, like anything, there are diminishing returns here).

 

Likely the USPS will have calculated how much range they need for the max distanced route, and that's how much range (plus extra) they'll get. I also have to assume the manufacturer will factor in driving characteristics, and range loss from low speeds, etc.

4 minutes ago, DeScruff said:

I did question if 300 miles was enough since I do know a mailtruck drives around a smaller area multiple times to get to every house. Knowing that I was unsure the exact miles a mail truck typically drives per day. However looking up and seeing the longest delivery route being a lil over half that (187.6 miles), then yes I acknowledge if these things could achieve 300 miles under their own usecase. It would be more then enough.

The figures thrown around earlier in the thread are around 120 miles average with 180-ish miles being the longest routes.

 

That's easily achievable with current technology, even with the efficiency losses.

 

Also, I forget who, but someone mentioned cold, and made an incorrect claim that ICE gasoline powered cars are not affected by cold. This is simply outright incorrect. The difference isn't as stark, but an ICE powered vehicle does lose range when it's colder.

 

Figures I've seen are around 15% efficiency loss at 20F vs 77F, and that figure will drop as it gets colder.

[poochyena]

4 hours ago, DeScruff said:

Cause everyone is telling you "Start stop start stop" vs constant movement is less efficient and you ask "SOURCE!?"

you are missing a word there, and that word is "significant". It was even bolded.

4 hours ago, dalekphalm said:

 

In an electric car, you also lose efficiency from start/stop. But you gain charge with regenerative braking. No, the regenerative braking doesn't fully make up for the starting again, but it does make up for a significant portion.

 

Someone said 64% above. So let's assume that every time they slow down, they regain 64% of that energy.

 

I think people are just making a lot of assumptions, and he's simply asking for proof.

Thank you. So glad someone here understands what I'm saying.

[MarvinKMooney]

It’s a massive boost over the current LLV’s it will have bloody AC!

[BiotechBen]

On 2/26/2021 at 4:18 PM, poochyena said:

but it is.

 

lmao, what? Do people in rural areas not have electricity?
They do. Its literally just a one or two day job to add some extra connectors to usps hubs to garage or yards that the trucks are parked at. They'll have 12 hours to charge, they don't need advanced fast charging connectors.

 

That makes no sense. Thats the cheaper option, the more expensive option is to buy a gas truck and then upgrade it later.

You can literally drive from one side of Iowa to the other, 300 miles, on a single charge from tesla model 3

Yeah, but a model 3 extended range is realisically 45-50k. These trucks are not gonna have 300 miles of range. They're gonna be like a ford transit connect sized can and they aren't going for that level of premium where people are going to pay whatever it takes. That tesla range is also not carrying anything. I would quote the rage for model 3 towing a trailer because that's going to be similar conditions to what they'll be under.

[BiotechBen]

On 2/26/2021 at 7:16 PM, poochyena said:

you should. Its a claim you made, so explain it.

 

uhh, where? The average is only one or two outages per year, lasting around 6 hours or less, according to this https://www.eia.gov/todayinenergy/detail.php?id=35652

If you live somewhere in the US that has regular long power outages, then you are in the tiny minority

Well texas was without power for a while.... Some number of combustion vehicles or fuel cell vehicles will be needed to some degree always. If it's going to be full electric, diversity in how electricity is generated will need to be attained. The generation of the electricity will also be a potential problem. If the grid goes down for 3 days, trucks are going to be without "fuel" for a while and be unable to make deliveries. If they want to source power from the grid for mass charging and then have some solar panels for emergency power for a few trucks and the post office then that's great. But going all BEV and relying on the grid to provide unfaltering electricity in the northeast is not really that great. In my neighborhood, every time there is more than 6in of snow or 30mph winds the power goes out for at least a day (suburbs of philadelphia) our power lines aren't buried so power can be pretty flakey in bad weather.

[Bombastinator]

1 hour ago, BiotechBen said:

Yeah, but a model 3 extended range is realisically 45-50k. These trucks are not gonna have 300 miles of range. They're gonna be like a ford transit connect sized can and they aren't going for that level of premium where people are going to pay whatever it takes. That tesla range is also not carrying anything. I would quote the rage for model 3 towing a trailer because that's going to be similar conditions to what they'll be under.

Assumptive.  Tesla’s have been out for a while and data has been collected on previous versions.  It might be like that it might not be like that.  It’s checkable though. 

[BiotechBen]

. 

 

 

36 minutes ago, Bombastinator said:

Assumptive.  Tesla’s have been out for a while and data has been collected on previous versions.  It might be like that it might not be like that.  It’s checkable though. 

Exactly. Oshkosh does military vehicles, they aren't tesla, tesla's range figures aren't exact as well. No range figure is exactly what it says. The days of driving until no fuel to find rage are over and now it's based on emissions in a stationary car with an algorithm applied.

[BiotechBen]

The smart thing to do is have them be plugin hybrids to start with like a small motorcycle engine to generate emergency electricity so that they can be easily retrofitted out with more batteries in place of the small engine.

[Bombastinator]

1 hour ago, BiotechBen said:

The smart thing to do is have them be plugin hybrids to start with like a small motorcycle engine to generate emergency electricity so that they can be easily retrofitted out with more batteries in place of the small engine.

Is and isnt.  The problem with hybrid is you’re dragging a generator along with you.  They can weigh a lot.  Also it negates the service advantages of electric cars which are pretty extreme.  An electric car can have only one moving part in its drive system.  There’s thousands of parts in just a transmission. A motorcycle engine based generator might make a certain amount of sense.  Do it military style.  Make the thing easily removable so if it breaks you just haul it out and slap in a new one while the first one gets fixed

Edited February 28, 2021 by Bombastinator

[BiotechBen]

54 minutes ago, Bombastinator said:

Is and isnt.  The problem with hybrid is you’re dragging a generator along with you.  They can weigh a lot.  Also it negates the service advantages of electric cars which are pretty extreme.  An electric car can have only one moving part in its drive system.  There’s thousands of parts in just a transmission. A motorcycle engine based generator might make a certain amount of sense.  Do it military style.  Make the thing easily removable so if it breaks you just haul it out and slap in a new one while the first one gets fixed

That's what I'm getting at. Something like a 350cc motorcycle engine hooked to a small generator that can be swapped out for a melon sized electric motor and mountable battery pack. This being aimed at where full BEV is not as easily attained. 

[Bombastinator]

1 hour ago, BiotechBen said:

That's what I'm getting at. Something like a 350cc motorcycle engine hooked to a small generator that can be swapped out for a melon sized electric motor and mountable battery pack. This being aimed at where full BEV is not as easily attained. 

That wouldn’t work.  The issue with gas engines is drive train.  There are two ways to do hybrid:  make the gas engine an electric generator and run everything through the electric motor, or make the thing an ice vehicle with various cutoffs and shunts so the electric motor can drive the driveshaft.  The volt is the first, the Prius is the second.  A sort of removable backpack electric generator is more or less what the i3 does except it turns out it’s not so removable so it runs basically like a volt. The mini e1 is an i3 with no ice engine and a bigger battery instead.  The driveshaft system is more efficient for gas engines.  The electric generator system has fewer parts, so longer life and easier maintainance.  It turns out that over 90% of people drive a vehicle for 20 minutes or less at a stretch most of the time. Commuting.  They don’t need batteries near the size of what they have.  The volt has enough battery to do this which makes it effectively an electric vehicle that drags around a gas engine all the time for the few instances when it is needed.  This is commuter passenger cars though.  A postal vehicle will have a different profile, and I suspect that profile varies pretty drastically by route. 

[Sarra]

As long as this means that my mail will be delivered to my house, and not the house a block up with the same number address, but different street, I'm okay with this.

[Bombastinator]

12 minutes ago, Sarra said:

As long as this means that my mail will be delivered to my house, and not the house a block up with the same number address, but different street, I'm okay with this.

I’ve had various issues not totally unlike that. The most effective move for my issues has been aword to the actual mailman that delivers to your house.   This changes occasionally without warning, so it must be kept up when one gets a new carrier.

[BiotechBen]

1 minute ago, Bombastinator said:

I’ve had various issues not totally unlike that. The most effective move for my issues has been aword to the actual mailman that delivers to your house.   This changes occasionally without warning, so it must be kept up when one gets a new carrier.

I've got the same carrier who refuses to drive down my driveway to deliver a package because there isn't a street box, but he will for the neighbors across the street who do. We have an address post. Direct quote from post office "we can't do anything about it. We have no control over the mail carriers"

 

[Bombastinator]

7 minutes ago, BiotechBen said:

I've got the same carrier who refuses to drive down my driveway to deliver a package because there isn't a street box, but he will for the neighbors across the street who do. We have an address post. Direct quote from post office "we can't do anything about it. We have no control over the mail carriers"

 

Sounds like you need a street box then.  Shouldn’t be terribly expensive.  Mail carriers are humans too.

[BiotechBen]

2 hours ago, Bombastinator said:

Sounds like you need a street box then.  Shouldn’t be terribly expensive.  Mail carriers are humans too.

Really the issue is with amazon not telling if they're doing them delivering or doing usps handoff for "final delivery". We're doing the Amazon Drop box now, it's just too convenient.

Like I'd be cool with them just like yeeting it out the window like a paper boy... I'm not usually ordering something that'll break from being tossed around a little.

 

[spartaman64]

On 2/27/2021 at 1:54 PM, poochyena said:

165,000 vehicles is absolutely significant when they are being driven even single day for many hours

 

omg that wasn't the point. So frustrating.
The point is if we have EVs that can go 300 miles, then we can absolutely have usps EVs that have to travel significantly less miles.

I don't think you are following the conversation. I'm asking for source to this specific claim in regards to EVs: "Accelerating a vehicle from a stop is significantly less efficient than staying at a set speed (say, 50 mph for EPA enjoyment). Guess what a USPS vehicle does? Start. Stop. Start. Stop. Start. Stop."

well inertia exists. objects at rest tend to stay at rest it takes more energy to get an object at rest to start moving than it does to accelerate a moving object. also its always well known that gas cars in the city is more inefficient than on the highway thats why they publish two miles per gallon ratings city and highway. 

also my point is its much easier to pump gas with a mechanical pump or a siphon than it is to store enough electricity in batteries or get enough backup generators to keep usps trucks running during an outage. 

[dalekphalm]

2 hours ago, spartaman64 said:

well inertia exists. objects at rest tend to stay at rest it takes more energy to get an object at rest to start moving than it does to accelerate a moving object. also its always well known that gas cars in the city is more inefficient than on the highway thats why they publish two miles per gallon ratings city and highway. 

also my point is its much easier to pump gas with a mechanical pump or a siphon than it is to store enough electricity in batteries or get enough backup generators to keep usps trucks running during an outage. 

There's a fundamental problem though: Outages shouldn't happen frequently.

 

Obviously that's a problem with US Infrastructure - a problem they caused themselves by not keeping up to date.

 

Ontario had that problem too - but after the infamous 2003 blackout that took down half the continent, Ontario invested in their infrastructure, and now we have one of the best ones out there. If I have a power outage more than once a year, that's unusual. And it normally only lasts a few minutes, or a few hours at most.

 

Yes there are certain challenges to EV's right now - particularly for someone like the USPS, but they're challenges that can be solved right now with the right investments.

 

I'm not opposed to the USPS buying some ICE vehicles still - but a lot of the excuses people have about why they shouldn't buy more EV's are largely non-issues.

 

The primary problem is simple: Money. If Congress gives them more money, they can get more EV's right off the bat. Hopefully Congress does that.

[AnonymousGuy]

What happens to the battery packs in an electric version of this thing?  They're just going to swap them out every 10 years?  Were they doing engine replacements that frequently with the current LLV?  Do the batteries actually die in 5 years with this sort of constant hard use that Tesla vehicles never see?

 

It's been said probably a ton of times but charging infrastructure is actually a significant problem.  Even doing something "basic" like putting a pedestal in a parking garage requires engineering effort because oftentimes *nothing* was built assuming you now need several thousand watts of power delivery in one area.  In a vehicle yard with a bunch of these vehicles you're probably talking about needing to do substantial upgrades all the way back to the transformers.  And oh by the way it's all been fully built on, so it's not as cheap as it was when it was under construction and everything was wide open.

[GDRRiley]

2 minutes ago, AnonymousGuy said:

What happens to the battery packs in an electric version of this thing?  They're just going to swap them out every 10 years?  Were they doing engine replacements that frequently with the current LLV?  Do the batteries actually die in 5 years with this sort of constant hard use that Tesla vehicles never see?

 

no, I'd expect they are built for ether 1/2 the life or the full life

no idea, go figure out how well GM i4 iron dukes last

you do realize there is a service in LA that uses teslas for long hall taxis, and they've got cards with 500k miles