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Tesla Semi

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If I understood correctly, axle is the metal rod/link that connects left and right wheels. Correct?

In the ICE world, no matter what the vehicle is, whether a semi or a car, you have only one engine. So you need axles and transmission to transfer power to all wheels. Right?

In the EV world, when each wheel can be fitted with a relatively inexpensive electric motor, why do we need axle? We know transmission isn’t there, same way with axle. Model S has axle because one motor is shared to control both left and right wheels.

On semi trailers they have axles and no motors. Why do you think that is?

Axle - Wikipedia
A non-driving axle, such as the front beam axle in heavy duty trucks and some two-wheel drive light trucks and vans, will have no shaft, and serves only as a suspension and steering component. Conversely, many front-wheel drive cars have a solid rear beam axle.

You don't put axles in just to put power to wheels.
 
I've never been in a semi, let alone driven one. With that out there... anyone have any ideas what sort of braking scenarios would likely be beyond what the regen braking could handle? We're all used to seeing "No Compression Brakes" signs as we enter small communities from highway speeds; think 65 MPH down to 35, etc. Will that noise pollution become a thing of the past? Would compression brakes more than likely just been used when the driver hasn't had time/warning to brake under normal driving conditions; and/or say on long descents, or when the battery pack is too full or unable to accept more regen? TL;DR, what are the likely limitations of the regen system in a Tesla Semi?

Yes. Compression brakes use oil pressure in the engine to engage a rocker level that keeps exhaust valves closed during the exhaust cycle iirc. The pressurized air is released just prior to the piston reaching top dead center on said cycle. This is what creates the noise. Electric motor regen will not have this issue.

Engine brakes are used for long descents to not burn out the actual brakes.

Electric regen would be superior to ICE engine braking because you will be able customize (and control) more the amount of desired regen.

Edit: more background info
 
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On semi trailers they have axles and no motors. Why do you think that is?

Axle - Wikipedia


You don't put axles in just to put power to wheels.
Of course you need axle when individual wheels aren’t directly powered by a dedicated motor. So, trailers obviously have axels.

If the Tesla semi has all its wheels (except trailer of course) each powered with a dedicated motor, there is no need for axel to connect those wheels.
 
Of course you need axle when individual wheels aren’t directly powered by a dedicated motor. So, trailers obviously have axels.

If the Tesla semi has all its wheels (except trailer of course) each powered with a dedicated motor, there is no need for axel to connect those wheels.

True, with dual motors per wheel set, there is no need for an axle shaft to connect the wheels to a center differential.
However, the outer non-motive portion of the axle is still useful for the load carrying aspect. Otherwise, it will need multiple multi-ton independent suspension units. This would require regular alignment checks/ adjustment. A solid axle has no alignment requirement (assuming it was built correctly and not overloaded)
 
Heavy EVs?

This 45-Ton All-Electric Dump Truck Will Be the World’s Biggest EV

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I think that Tesla is working closely with fleet operators to optimize the product for their needs. But when it comes to sales Tesla has strongly resisted having fleet sales of autos at lower price than for individuals. Musk has very strong view that there should be one transparent price for all, albeit there has to be some adjustment for quoting prices in different currencies and for homologation and delivery to other countries. Additionally, Tesla has set a lower price for Powerpacks on orders above 100 MWh.

Given that history, my expectation is that Tesla will sell Semis through the web to any buyer at the same national price. I believe they will fight the temptation to offer lower prices to large fleet operators. However, I do believe that Tesla will work closely with clients to set up charging and solar power generation infrastructure. This is an area where large fleet operators can have an enormous scale advantage and Tesla can help them achieve that. Naturally, as an operator builds out a cheap supply of charging, they will find more value in increasing the size of their Tesla fleet. So there is no need to offer fleet discounts on Semi when you have fleet charging.

It is also important to understand that developing low cost fleet charging is a hedge against the rest of truck makers lowering prices to these operators to attempt to retain market share. Surely competitors will try this. But if you've got charging and surplus power at your site, then you are willing to pay more for a Tesla Semi that can use that power than for a diesel semi that will force your fuel bill to go up.

So fleet charging is key to fleet sales. Otherwise, I expect Tesla to market trucks at the same price regardless of buyer.
 
Pretty sure its going to be fleet only, but we'll know in about a month...

I'm pretty sure Tesla will sell to individuals. However, the truck charging system is not clear yet, and the finances of that may be worse for individual truckers than for fleets with economies of scale. We'll see.

So, yep, we've got the typical TMC consensus on this question. I.e. None. :)
 
IMO, Tesla will want to have the largest market possible for the greatest impact, so they will sell to large fleets, small fleets and individuals, although the first customers will probably be fleet operators. I also believe they will have an aggressive plan to develop the charging, service and support infrastructure to support all types of customers because that's how they roll.:)
 
So, yep, we've got the typical TMC consensus on this question. I.e. None. :)

Tesla will likely sell to individuals... IIRC, Elon said something along the lines of - you'll be able to rent a Semi on Tesla Network -

Even IIRC, not sure if that conclusively means Tesla will sell Semi's to individuals, my educated guess is that they will.

It'd be very interesting if Tesla created an uber-like service for transportation of goods and individuals could add their Semi's on that network.
 
Until we advance down the EV road another 5-01 years it's going to be tough to sell an individual semi that's super-impactful right out of the box. The charging infrastructure needs to be developed hand-in-hand.

I imagine these first few fleet applications will be custom designed and optimized for the routes and distances traveled. It'll be almost like building out a disconnected monorail system.
 
I think Tesla (Elon) is not afraid of changing some basic concepts of trucking. I assume the following has been done:

- The truck itself has a short range battery, roughly 300 km at 80 km/h unloaded.

- The cargo trailer has batteries under the floor for extending the range up to total 1000-1200 km at 80 km/h.

- The cargo trailer has atleast one axle with a motor/regen. This to solve regenerating in a good way without applying brakes or transferring all load to the truck (not good with big loads or on slippery roads). Also improves traction uphill.

- The trucking concept changes: Regular customers has the trailer battery charging at their place. The truck delivers a full cargo trailer with near empty batteries, and pick up the empty trailer with full batteries. Deliver empty trailer at other company, pick up full etc... For parcel transport you pick up a fully loaded trailer at each delivery point and leave the other behind for sorting. Bonus: Eliminating driver waiting for unload, 100% effective drive, faster parcel delivery.

- The truck destination slow-charges only at night and can drive a full day with different trailers. Tesla destination chargers are mounted on regular truck stops around the world.

- The trailers slow-charge at their destinations.

- The cargo trailers can have different sized batteries for different uses/stretches, but they couple to the same truck. Larger battery trailers for customers that don't destination charge and for long hauls. Bigger battery trailers have longer range, but are more expensive and have smaller payload weight.

- These trailers will also work well with end-point destination parcel delivery circled around a storage facility. Pick up trailer, drive it around and put it back empty for charge. Pick up new trailer. Use these semis for big volume areas.

- Later Tesla will probably develop smaller vans for door-to-door delivery.

- The cargo trailer can slowly drive on its own using remote control without a truck. So customers and facilities can move them around when they're done charging/loading. There's gotta be one advantage of being electric.

- Truck will have the best acceleration on the market.
 
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Two quotes from Musk to Electrek about the Semi.

Why the Tesla truck will turn freight industry upside down


“It is a heavy duty, long range, semi-truck. So it has the highest weight capability and with long range. So essentially it’s meant to alleviate the heavy duty trucking loads. And this is something which people do not, today, think is possible.

“They think the truck doesn’t have enough power or it doesn’t have enough range. And then with those with the Tesla semi we want to show that no, an electric truck actually can out-torque any diesel semi and if you had a tug-of-war competition, the Tesla semi what will tug the diesel semi uphill.”
 
Pretty sure its going to be fleet only, but we'll know in about a month...

I'm pretty sure Tesla will sell to individuals. However, the truck charging system is not clear yet, and the finances of that may be worse for individual truckers than for fleets with economies of scale. We'll see.

So, yep, we've got the typical TMC consensus on this question. I.e. None. :)

Thanks all. I keep coming back to thinking along the lines of neroden (which is why I asked the group). While it seems very much like Tesla to sell to individuals, I'm not yet seeing a realistic/convenient path for individuals to charge such a beast right now. Whereas, I can very much imagine fleet operators (i.e. Walmart) with their own point to point charging infrastructure which is of the necessary scale. That said, I live in Idaho and the Supercharger build out on the map for the next year along I-84 got me thinking about what Tesla might have up their sleeve for accommodating the Semi. Currently, I-84's Supercharger locations are all quite manageable (~130 miles apart) in a Tesla and yet they are adding SCs that will shorten these hops by about 1/2 - so ~60 miles apart. It's great, but some have thought it's a little odd given that other routes from say Boise, ID to like south western Oregon, or to California(!) are really difficult right now with the SC network. You have to go way out of your way to make it work. So, the prioritization seems a little weird to me unless there's something we don't know. This got me thinking about these new, upcoming locations. Is there something different about them? They all definitely seem to be really pro-truckstrop. So much so that I started researching those big brands - especially Love's to see what their location footprint might look like relative to these new locations. There is overlap, but it's not a slam dunk. I guess we shall see in a few weeks. Thanks for the thoughts...
 
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Will any of these trailer battery packs make the sea voyage with the cargo? If so you could trickle solar charge them all by floating and dragging a half mile long thin-film array behind the cargo ship.

Would you use the battery packs on board to help power the ship itself?
 
Custom trailers with battery packs seems risky, but could also be very successful.

"If" Tesla has their own trailer design, no doubt they will be using these trucks between GF1 and Fremont to sell the idea to fleet customers. Could also be used for shipments leaving GF2 when it gets up and running.