Tesla Semi, 500-miles

[aerohead]

I won't attempt any particulars about the recent 'reveal', as there aren't any particulars published yet, but the rig did succeed in covering 500-miles distance on a charge, @ 81,000-pounds GVW, in California, @ 55-mph, including the Cajon Pass.
On a 'gallon-of-Diesel' basis, it's at least 350% more efficient than the 'typical' Diesel 18-wheeler on the road.
It will charge @ 1- Mega-Watt/hour.
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Some working numbers:
* Tesla Tractor- 15,700-lb
* Dry Van- 21,300-lb ( empty ), L=55-feet, W= 102-inches, H= 13'-6-inches
* 45,000- lb cargo capacity
* Projected Frontal Area- 108-sq-ft ( 10.03352871 meters-squared )
* Cd 0.36 ( has been mentioned, but is determined by the trailer ), so it remains an 'unknown quantity' )
* Coefficient of rolling resistance @ 55-mph: Cfrr- 0.008181818
* Tractor-to trailer gap: yes, unspecified distance
* Boat-tail : none
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* 'Supertruck'- Cd 0.3953
* 'Futuretruck,' Cd 0.2635
* NASA Semi-trailer, Dryden Research Center, Edwards AFB, 1980, Cd 0.238
* Walter Korff, Lockheed Aircraft Corp., Semi-trailer, 1963, Cd 0.20

[JSH]

Originally Posted by aerohead

I won't attempt any particulars about the recent 'reveal', as there aren't any particulars published yet, but the rig did succeed in covering 500-miles distance on a charge, @ 81,000-pounds GVW, in California, @ 55-mph, including the Cajon Pass.

I watched the video. The description over on Autoblog is accurate:

The numbers we can see show what looks like some tenderfoot driving. Keeping in mind that the speed limit for Class 8 trucks is 55 mph in California, the Semi did 55 or below for the opening stint; at one point doing 29 mph on what looks like open highway. The driver follows another rig on I-5 at about 60 to 65 mph for a spell, up to about the one-third mark in the trip. Then he locks into 55 or 57 mph for the long stint through central California, dropping as low as 44 mph and 39 mph for a surprising length of time.

For the final 100-mile stretch from Riverside to San Diego, after the driver takes his mandatory break, he doesn’t exceed 51 mph in the video, dropping as low as 47 mph on open highway.

Average speed has to be less than 55 mph. (Which is likely why Tesla did not release the full uncut video like Musk said they would from the stage - it would be easy to calculate the actual moving average)

Congrats to Tesla for delivering their first Semis but it is hard to claim a 500 mile range when the truck is going under the lowest truck speed limit in the USA.

Originally Posted by aerohead

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Some working numbers:
* Tesla Tractor- 15,700-lb

That would make it 1,000 lbs lighter than the dry weight of a Freightliner Cascadia day cab. That isn't likely considering the 1,000 kWh battery. (Musk said it averaged 1.7 kWh / mile on that run so with a 10% battery buffer it would be 1005 kWh)

Some educated guesses are putting the Tesla Semi 300 at about 25,000 lbs +/-

Musk being Musk also had to throw out some crazy sale projections. He said Tesla will sell 50,000 Semis in 2024. For reference that is about 25% market share for Class 8 trucks in the USA. So considering volume production is expected to start until mid-2023 that is 0 to 25% in 18 months.

[redpoint5]

Tesla had better under-promise and over-deliver in the commercial trucking sector. That industry isn't going to tolerate drivers getting stranded due to running out of juice due to unrealistic range expectations.

I don't even know what you do if a truck runs out of juice. Probably unhitch the load and tow the tractor, and get a second tractor to finish pulling the load.

I wonder how feasible it would be to have dispatchable chargers that can provide an emergency "quick" charge. It would have to be battery based since hauling around a megawatt genset isn't practical (or is it?).

[wdb]

I'm watching this rollout with a lot of interest. It seems to me to be a very good application for electric power. Range limitation is based not only on energy capacity but laws surrounding driver stints. Known start and end points make for easy, practical recharging and tractor swapping processes. Electric semis could everything but the 'last mile' of hauling, and in many circumstances such as warehouse destinations they may even do that. Pretty exciting, in a nerdy kind of way.

[redpoint5]

Last mile seems a better application for EV since the speeds are lower and there's more stop and go. On the contrary, cross-country travel is the hardest nut to crack for EV trucking.

I don't know the industry lingo, but it seems the Tesla semi is targeting the mid-distance hauling, which is still a difficult problem to solve.

Will be interesting to be in traffic with these trucks that are capable of accelerating like a car. Used to be able to plan to pass a truck knowing it will be slow to accelerate. Would be annoying to not have enough power to pass on a straight section but then get slowed down in corners behind these rigs.

[Hersbird]

The actual weight of the cargo is the other number they really need to release. Until they do the claim by Daimler and Gates it couldn't be done really still stands. It wasn't the 500 miles that would be impossible because even 2000 miles would be possible by putting nothing but batteries in the trailer, but having a traditional 45,000 pounds of cargo and going 500 miles on a single charge is what's difficult. Daimler's trucks have smaller batteries to keep the weight similar to a diesel setup so they have lower ranges.

[JSH]

No - the commercial sector does not tolerate a company underdelivering. They expect the product to meet the spec. They demand continuous uptime and any problems to be fixed under warranty in 24 to 48 hours. (Every day a truck is in the shop cost the owner $1500 to $2000 in lost revenue). Commercial customers won't wait for weeks to get their vehicle fixed like Tesla's current customer base. Big fleets will buy a test fleet and then run them for 3-5 years to determine a baseline for Tesla. It is all about total cost / mile, uptime and service.

You tow dead electric trucks just like a dead diesel truck. It takes a really big wrecker and they can tow the tractor / trailer combo as one. Vehicle to Vehicle charging exists today so that could be a possibility.

The 500 mile semi is targeting region hauling. There is no way it is going to do long haul where drivers run 700 miles in their 11 hours of driving. Driving at a normal speed this truck likely has a 350 - 400 mile. It does make a lot of sense for depot to depot hauling where the truck owner also owns the infrastructure on both sides.

Yes, the weight of the tractor is key. Every extra pound on the tractor is one pound less cargo that can be carried. The "Breaking the Laws of Physics" statement is yet to be determined. My gut tells me the Semi is thousands of pounds heavier than the equivalent diesel day cab used for regional hauling. The eCascadia with a 438 kWh battery weighs in at 21,800 lbs according to the Freightliner website. Tesla will save some weight by building the Semi to be BEV from the ground up but that battery is huge. For reference the Nikola Tre with a 733 kWh battery weights in at 29,800 lbs.

Daimler and Volvo are targeting drayage and urban use with their electric trucks. The ranges aren't huge because they don't need to be and the truck returns home every day. That keeps the tractor weight low and reduces the cost. Tesla's 300 mile version is also targeting this usage. Commercial customers buy what they need - not more. I expect the 300 will be Tesla's volume seller.

Tesla also talked about Megawatt charging. I REALLY hope this is just Tesla rebranding the MCS standard being worked on internationally. CharIN is heading up the standards effort and their design is good for 1 MW to 3.75 MW. The applications are HD trucks, ships, and airplanes and there are a lot of companies / industries involved hoping to create on charge standard to rule them all instead of the 4-5 different plugs we have with light duty vehicles.

[redpoint5]

Engineering Explained has another video talking about the Tesla Semi.

Estimates are:

Battery weight 10,000 lbs
Battery capacity 850 kWh (usable)
Max cargo weight 44,000 lbs
Cargo weight deficit ~6,000 lbs compared to conventional ICE

Turns out 2/3 of trucks "cube out" and 1/3rd "weigh out", meaning most run out of trailer volume rather than run out of weight capacity.

Do you think we'll reach 50% of commercial hauling going electric first, or 50% of passenger vehicles?

https://www.youtube.com/watch?v=hvg_i0GE0Vo

[Piotrsko]

10,000 , 20,000, 30,000 new OTR trucks a year vs 1.3 million teslas? My guess is no.

[freebeard]

Negatory on an OR question?