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Interesting. :)

It's not really a Cummins truck; it's a prototype of a Cummins powertrain for Class 7 trucks and similarly-sized buses, shown in a demonstration truck built by Roush.

From Cummins (via their "social" site, because this is all about publicity rather than transportation):
5 COOL THINGS ABOUT OUR ELECTRIC POWERTRAIN CONCEPT TRUCK
The five things are:
  1. It's all electric!
  2. It has plenty of other energy-saving features
  3. Its environmental impact
  4. It's all about options
  5. It has Cummins' size and experience behind it
Only the first two contain any technical information:
  • It's all electric!
    • 140 KWh battery pack
    • "The weight of the electric powertrain is roughly equal to that of the removed engine, aftertreatment, transmission and fuel tank" - perhaps because it has a relatively low-power motor and very limited range
    • "The tractor day cab when paired with a trailer has a gross vehicle weight rating limit of 75,000 pounds."
    • "The concept truck has a range of about 100 miles on a single charge for city driving that’s extendable to 300 miles with additional battery packs" - no weight is given for the main battery, or the additional capacity
    • "The powertrain and truck will enable Cummins to learn more about the potential electrification holds for larger vehicles." - in other words, this is still a development effort, not yet a viable product
  • It has plenty of other energy-saving features
    • "regenerative braking system" - of course!
    • "the potential for solar panels on the trailer roof" - that's just fluff for people who don't know anything
    • "Air drag is reduced by replacing side mirrors with an in-dash camera system" - unlikely to be legal, and would be just as applicable on a diesel truck
    • "The truck achieves a significant air drag reduction via its highly streamlined design as well as a better sealed truck body and underbody – with no front radiator intrusion" - it likely does have a radiator, but certainly the electric powertrain requires much less cooling airflow and resulting drag; the smoother underbody is another EV benefit
One more "thing" contains an interesting note:
  • It's all about options
    "Diesel engines aren’t going away. The company expects diesel to be a popular option with customers for years to come."​

The photos on that Cummins page show a couple of other details:
  • wide-base single tires are used on the drive axle (for lower rolling resistance, another feature that could be used on any truck, but is necessary to make the electric truck even remotely viable)
  • there is a large box on the back of the cab, likely for battery, which is interesting given the massive volume available in the side pods and under the hood

The demonstration truck appears to have an International cab, and so presumably the corresponding International chassis. The lack of any identification of International suggests that they didn't fund, support, or endorse the project... although it may also just be Cummins striving to stay brand-neutral, to avoid offending any potential customers (who are the truck manufacturers, not truck operators). I suppose the price of a truck (especially just a glider) is nothing on the scale of these projects, so they didn't need International.
 

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Discussion Starter · #3 ·
Until much improved battery performance ..weight, power, quick charging, size , cost , etc.....become available, i would think these "Semi" type tractor rigs would be a good subject to use replaceable battery packs on .
They lend themselves to large , easily accessible, simple shaped, battery packs that could be swapped out quickly at service areas.
Probably quicker than refueling a few hundred gallons of diesel into a tank.
..A bit like mini container packs but onto the tractor unit.
 

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Until much improved battery performance ..weight, power, quick charging, size , cost , etc.....become available, i would think these "Semi" type tractor rigs would be a good subject to use replaceable battery packs on .
They lend themselves to large , easily accessible, simple shaped, battery packs that could be swapped out quickly at service areas.
Probably quicker than refueling a few hundred gallons of diesel into a tank.
I think that's a great idea. :)

Battery-swapping has proven to be a failure for general-purpose consumer vehicles, for a few reasons:
  1. few consumer vehicles would physically accommodate a readily swappable battery configuration
  2. personal vehicles will be inconsistent, so the best battery configuration will not be the same for all of them
  3. even within one vehicle type, obtaining consensus on a completely single battery specification will likely be impossible (they can't even agree on a charging plug now!)
  4. few owners want to swap their battery for an unknown, so it is really viable only for leased batteries under a contract that includes the swapping
  5. each swap delivers a different amount of energy - depending on what was left in the battery which is turned in - so swap pricing would be challenging
  6. having stocked battery swap depots everywhere they might be needed is not feasible, especially for a small number of users spread over a wide area
A commercial route is another matter entirely...
  • Karter2 already addressed the first item.
  • All batteries and trucks would be owned by the same operator, and would be interchangeable, making the next four issues go away.
  • In any local service in which the truck returns to the base during the day, the operation could be supported with a single swap depot. Even for short hauls up to a substantial fraction of the battery range, if they are on a repeated route a swap depot at each end would work.
There are precedents for the idea of depots dedicated to a specific fleet of vehicles with a special energy need. Vehicles fueled by compressed natural gas are rare, but where they have been successful has been where a fleet operates one local area with dedicated filling stations, or overnight refuelling, typically in utility company service operations. Long-haul trucks can run on liquefied natural gas, but there are no stations; a fleet here ran for a while on a single regular route (of a few hundred kilometres) supported by a couple of LNG filling stations which were justified essentially by that one fleet.

..A bit like mini container packs but onto the tractor unit.
Do you mean onto the truck, between the cab and the trailer, like a dromedary contaier (or drom box)? It would be much smaller than these boxes on moving vans. That would work, but the length of the truck could be a bit of an issue (especially with a conventional, rather than a cab-over-engine). I think that hanging packs on each side in the usually saddle fuel tank location would work, and might be easier to handle.
 

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Discussion Starter · #5 ·
...There are precedents for the idea of depots dedicated to a specific fleet of vehicles with a special energy need. .....
There certainly are. Its a long established and well proven practice ...
....as initially used by Wells Fargo, etc about 150 years ago ! :D
 

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....as initially used by Wells Fargo, etc about 150 years ago !

I assume that was for "Stage Coaches" and horses - in which case it was actually used by the "Post" a couple of hundred years before that

And I think the Romans used it a wee bit before then
 
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