# Tesla Semi delivery event



## remy_martian (Feb 4, 2019)

Meh - three (or four?) years late to the party and yield must be so bad on the 4680 cells that they gave up on using them in the Semi, in favor of the smaller Model 3 cells, so they could ship SOMETHING in CY2022.

I suspect there's a massive cash bleed on this one, given it was priced with the cheaper 4680 dry cells. Other electric semi trucks have been in production for more than a year. Even Nikola beat Elon to market 😂


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## cricketo (Oct 4, 2018)

Is there one that can do 500mi fully loaded ?


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## remy_martian (Feb 4, 2019)

I see Elon served his Koolaide at the launch
😂


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## cricketo (Oct 4, 2018)

That was a serious question. I know Daimler has a "300mi" one, and we don't know where/how it's supposed to recharge. Tesla is trying to provide a complete solution with fixed specs. We will know if they succeeded after PepsiCo and such will log some miles and share their impressions, but who is the real competition in that space ?


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## remy_martian (Feb 4, 2019)

We do know how the Daimler is supposed to charge - the PGE CEO was at the ribbon cutting for the charger a year or two ago, lol.

Daimler & Volvo own the semi market. Tesla did some nice sales pitches for them in 2018.

Pepsi is a captive customer, as is Frito Lay and Fedex. Go try to buy a Tesla Semi and they'll likely tell you to pound sand. 

Daimler is building to order. On an assembly line in Portland. You can buy one. Volvo is supposedly stall-built. Don't know much about the Kenworth.

When the Koolaide wears off and you come to your senses, you'll realize that Tesla trades payload for range. They're using the same battery tech everybody else is. 

Tesla's use of four motors vs two is not going to add 70% to anyone's range, lol. Wake up, boy 😂

All of these trucks are for regional distribution. None are long haul trucking market, despite Musk's hype. These are established trucking companies with established customers that they can get data from....not a bunch of car guys building trucks. 300 miles clearly fits the 80/20 rule.


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## cricketo (Oct 4, 2018)

I don't quite understand your response. You're saying Tesla semi hauls less than the competition ? I understand the part about the ability to order, Tesla received pre-orders with a significant commitment from those companies, so of course they will work day and night to satisfy those first customers before it becomes available to the general public. Nothing wrong with that.

From the presentation it seemed like it wasn't using 4 motors, but just 3.

Why wouldn't they work for long haul if the infrastructure is built out ? Tesla is still the leader in charging infra, if they want to make this happen, I have no reason to doubt them.


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## Duncan (Dec 8, 2008)

The Tesla Semi will "rule" - they will make and sell far more than the competition - AND when Full Self Driving comes in .......

Give it two years and people will have difficulty giving away the competition


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## reiderM (Dec 30, 2020)

Duncan said:


> The Tesla Semi will "rule" - they will make and sell far more than the competition - AND when Full Self Driving comes in .......
> 
> Give it two years and people will have difficulty giving away the competition


That's assuming they can build enough which considering the battery capacity these will have I don't think they'll make a whole bunch for now. 

Still a place for Diesels for long-haul, at least here in the States where charging infrastructure in a lot of the country is pretty poor.


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## cricketo (Oct 4, 2018)

Semis have 1MWh batteries, so that's an equivalent of ten higher end S or X models. Not a huge problem given the semi market is significantly smaller and they constantly keep increasing their production capacity. I think they will be able to keep up with the demand.


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## remy_martian (Feb 4, 2019)

You missed the part about not having the cheaper 4680 in this reworked product release.

Until Panasonic sorts out Tesla's cell manufacturing mess, either the price will need to go up, or they will bleed cash with each unit shipped. At 2 units per day, just Pepsico and Fedex are backlogged for about six months.

A Class 8 truck is a Class 8 truck. Until you equip it with the weight of batteries to get 500 miles of range. Tesla is the ONLY electric semi where I've seen range quoted as 300-500 miles. With Federal weight limits on the Class, guess how you get that extra 200 miles? No, not Elon Magic.


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## cricketo (Oct 4, 2018)

Battery capacity imposes the absolute maximum range limit, and conditions / terrain / load will impose additional limits on top. They got 500mi out of it on a real route at 82k, but indeed we still don't know what their dry weight is.

Now regarding Federal weight limits, it looks like electrics are allowed extra 2,000lb since recently.


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## brian_ (Feb 7, 2017)

cricketo said:


> You're saying Tesla semi hauls less than the competition ?


Whatever was intended, it is true that more range means more battery which means less payload in a weight-constrained application. Many applications are constrained by volume or just by the size of a specific payload, rather than by truck GVWR limits or legal limits. Other manufacturers are generally targeting shorter range (like the Tesla "300 mile" option), simply because that's appropriate for the applications for which battery-electric make the most sense.



cricketo said:


> From the presentation it seemed like it wasn't using 4 motors, but just 3.


The original presentation (a few years ago) showed 4 motors: two per axle, independently driving wheel sets. The motors were to be those of the Model 3, but of course with a different reduction gearing configuration; they were even reportedly using different gearing ratios between axles.
Recent reports talk about 3 motors, which presumably means that one axle is as originally shown, and the other has a single motor plus differential. I haven't even watched today's presentation for confirmation yet.

Of course the number of motors is nearly irrelevant to efficiency and range. Tesla is using axle-mounted motors, which leave as much space as possible between the frame rails for battery; they're not the only ones. Some other manufacturers use traditional axles and frame-mounted motors, which can be as few as one (but Volvo puts two motors on one transmission for sufficient power, and a tandem drive axle configuration could use a motor or motor pair to drive each axle).


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## brian_ (Feb 7, 2017)

Duncan said:


> The Tesla Semi will "rule"
> ...
> Give it two years and people will have difficulty giving away the competition


Nothing about this truck or Tesla in the automotive market supports this assertion. Yes, they may get a good market share, but they have no technical advantage, and even in the passenger car market none of their competition has trouble selling product.


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## brian_ (Feb 7, 2017)

cricketo said:


> Why wouldn't they work for long haul if the infrastructure is built out ?


If the battery capacity is not sufficient for a full driving day (and 500 miles is not sufficient in long haul) then fast charging at short breaks (lunch?) is required. That is expensive infrastructure, and even if it is built out it is much more expensive to use than slower charging at corporate facilities.


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## reiderM (Dec 30, 2020)

Semi trucks will lag the consumer automotive market in EV adoption by about a decade IMO. Batteries are just too damn expensive at the moment, which makes electric semis exceptionally expensive upfront. 

At $130/kwh for li-ion battery manufacture (current cost) that's $130k in batteries alone. Adding in everything else and you're at likely over $200k in just production costs. How Tesla expects to sell these for less than $200k is absolutely beyond me given the current market. I'm sure they can eat a loss for a handful of units but it's not sustainable long term at all.

I would expect that the base Tesla semi will retail for close to $300k.


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## Duncan (Dec 8, 2008)

remy_martian said:


> You missed the part about not having the cheaper 4680 in this reworked product release.
> 
> Until Panasonic sorts out Tesla's cell manufacturing mess, either the price will need to go up, or they will bleed cash with each unit shipped. At 2 units per day, just Pepsico and Fedex are backlogged for about six months.
> 
> A Class 8 truck is a Class 8 truck. Until you equip it with the weight of batteries to get 500 miles of range. Tesla is the ONLY electric semi where I've seen range quoted as 300-500 miles. With Federal weight limits on the Class, guess how you get that extra 200 miles? No, not Elon Magic.


How do you get the extra 200 miles

Probably the same way that Tesla cars are better than most of the opposition - by designing it as an EV from the start - not simply replacing a diesel with a motor

Rough numbers
Model X - 350 miles range - battery 600 kg
A big car like the X would have a diesel MPG of about 21 mpg
A Semi is about 7 mpg 
So three times the consumption - and twice the range (700 miles) - is six times the battery - 3,600 kg 
Lets say that 3.6 ton battery will take you for 500 miles 
Lose the engine and gearbox and all of the rest of the junk - 3 tons - replace it with 400 kg of motors
Net gain 1 ton
I'm pretty sure that a redesigned Semi could easily lose a ton!!
But if it didn't then that would be 1 ton of payload lost - as in 2.5% - not a big sacrifice for a massive reduction in fuel costs


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## Duncan (Dec 8, 2008)

reiderM said:


> Semi trucks will lag the consumer automotive market in EV adoption by about a decade IMO. Batteries are just too damn expensive at the moment, which makes electric semis exceptionally expensive upfront.
> 
> At $130/kwh for li-ion battery manufacture (current cost) that's $130k in batteries alone. Adding in everything else and you're at likely over $200k in just production costs. How Tesla expects to sell these for less than $200k is absolutely beyond me given the current market. I'm sure they can eat a loss for a handful of units but it's not sustainable long term at all.
> 
> I would expect that the base Tesla semi will retail for close to $300k.


Its more like $100/kWh
And the Semi will have about 600 kWh 
Which drops the $130K down to $60K - 
Add the same as you thought for "everything else" and we get $130K as total cost
Selling at $200K is a very very decent margin!


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## brian_ (Feb 7, 2017)

Duncan said:


> How do you get the extra 200 miles
> 
> Probably the same way that Tesla cars are better than most of the opposition - by designing it as an EV from the start - not simply replacing a diesel with a motor


No, you get the extra 200 miles, at 2 kWh/mile, with 400 kWh more battery. the Tesla Semi is very conventional: it has an normal heavy truck frame, axles, suspension, brakes, and general cab configuration (the goofy central-seat cab is an unimportant distinction). There's no evidence of "designing it as an EV from the start" about the fundamental design.



Duncan said:


> Rough numbers
> Model X - 350 miles range - battery 600 kg
> A big car like the X would have a diesel MPG of about 21 mpg
> A Semi is about 7 mpg
> So three times the consumption - and twice the range (700 miles) - is six times the battery - 3,600 kg


Good try, but way off. Musk has confirmed that the Semi's consumption when loaded to about 80,000 pounds is about 2 kWh/mile - that's six times Model X consumption, not three times. And there's nothing wrong with that, given the relative sizes of the vehicles and their shapes.



Duncan said:


> Lets say that 3.6 ton battery will take you for 500 miles
> Lose the engine and gearbox and all of the rest of the junk - 3 tons - replace it with 400 kg of motors
> Net gain 1 ton
> I'm pretty sure that a redesigned Semi could easily lose a ton!!
> But if it didn't then that would be 1 ton of payload lost - as in 2.5% - not a big sacrifice for a massive reduction in fuel costs


A realistic battery weight:
500 miles * 2 kWh/mile * 5 kg/kWh = 5,000 kg (5 tonnes)
You can't replace the engine and transmission with just motors - you need the reduction gearboxes for the electric motors as well. A better comparison is to assume that the electric drive units weigh about as much as the diesel truck's transmission, and that diesel-related accessories are comparable to EV-related accessories, so it's a matter of replacing two tonnes of engine and exhaust system with 5 tonnes of battery, for a net 3 tonne increase... plus or minus a substantial margin for error.

I agree that the weight penalty is manageable for many applications... but not all.


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## brian_ (Feb 7, 2017)

brian_ said:


> Recent reports talk about 3 motors, which presumably means that one axle is as originally shown, and the other has a single motor plus differential. I haven't even watched today's presentation for confirmation yet.


I was going to watch the Tesla video, but it's an hour long. Instead I fast-forwarded through the nine-minute version by CNET, and there at 2:20 is the motor setup. It is as I expected, although the sloppy graphic work doesn't clearly show the differential in the single-motor axle (which they call the "highway drive unit", because the two-motor axle can be disconnected for reduced frictional loss in cruise). The single motor axle won't have control of left-right torque distribution, so it will need a lockable diff (common in conventional trucks) for the worst of winter conditions.


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## brian_ (Feb 7, 2017)

Earlier promotional material showed two cab lengths, suggesting a shorter day cab and a longer sleeper cab. As the video shows, the long version is still only a day cab. The interior space ends at the back of the doors, which are well short of the back of the cab; that means that the extra length is a stack of battery above the frame... just like a BYD Class 8 day cab tractor, but with a nicer fairing over it.

Longer-range hydrogen-fueled fuel cell trucks have been shown with a similar behind-the-cab energy storage feature (tanks in that case).

Long haul without a sleeper? It can work (motels exist for a reason) but it's somewhat limiting.


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## cricketo (Oct 4, 2018)

brian_ said:


> If the battery capacity is not sufficient for a full driving day (and 500 miles is not sufficient in long haul) then fast charging at short breaks (lunch?) is required. That is expensive infrastructure, and even if it is built out it is much more expensive to use than slower charging at corporate facilities.


Federal law requires minimum 30 min break for 8 hours of driving. On many routes 500mi in 8 hours won't be even possible due to truck speed limits, scales, and traffic when going through populated areas. I believe with sufficient infra 500mi range can be basically unlimited range if every quick food/bathroom stop results in 10-15 minute charge top off. But the cargo capacity is a better question, perhaps 300mi range + better charging would be a better option.


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## cricketo (Oct 4, 2018)

brian_ said:


> No, you get the extra 200 miles, at 2 kWh/mile, with 400 kWh more battery. the Tesla Semi is very conventional: it has an normal heavy truck frame, axles, suspension, brakes, and general cab configuration (the goofy central-seat cab is an unimportant distinction). *There's no evidence of "designing it as an EV from the start" about the fundamental design.*
> 
> 
> Good try, but way off. Musk has confirmed that the Semi's consumption when loaded to about 80,000 pounds is about 2 kWh/mile - that's six times Model X consumption, not three times. And there's nothing wrong with that, given the relative sizes of the vehicles and their shapes.
> ...


They have called out the exceptional aerodynamics, which is a component of that. Daimler has a conventionally shaped cab, and there is likely a penalty for that. In a diesel they could get away with that by making the fuel tank bigger, not so much in an EV.


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## remy_martian (Feb 4, 2019)

No...you are still dealing with the drag from the abrupt termination at the back of the trailer and its open wheels.

The Daimler trucks have fairings - they have been competing in fuel economy for decades. "Just burn more diesel" sends customers to the competition.

You must be peeing a lot with all that Musk-aide you've been guzzling 😂 Aero on the front of the truck is lipstick on a pig... that and the centered driver is more crap Musk has stolen from the covers of his 1950's Mechanix Illustrated collection.


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## cricketo (Oct 4, 2018)

https://airshaper.com/cases/tesla-semi-truck-aerodynamics-analyzed


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## remy_martian (Feb 4, 2019)

That freestream (yellow) line, where the flow separates, is supposed to be at the ground, fanboi.


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## cricketo (Oct 4, 2018)

You can easily share another analysis to demonstrate how Tesla is misrepresenting the reality. I don't have a dog in that fight, I just appreciate them doing something different.


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## remy_martian (Feb 4, 2019)

The only thing different is they have a master bullshitter at the helm, and, as CEO and major stockholder, he has the power to BS well beyond what any marketing exec would get approved to do.

Nothing they are doing is any different than anyone else, now.

The Maxwell dry cell tech in the 4680 was their trump card, and they can't seem to get the things to yield with all the cracking when they roll the cell. The "tabless design" was supposed to fix that (you also probably fell for the "superior cooling" sleight of hand Musk stated as to why they did tabless to detract from yield concerns, yet those "cooling" tabs sit on a chunk of ABS plastic in the Monro teardown).

Nothing is different. Both full self driving and the dry cells are still, eternally, two years away.


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## Electric Land Cruiser (Dec 30, 2020)

It does 2kwh/mi and has 1000kwh. Not sure what the controversy is. They posted a video of the 500 mile drive on their youtube channel. It looks like it's limited to 55mph the whole way and sticks to the right lane so it's a realistic run. 

They can sell them for $200k because they aren't just going to sell a truck. They are going to sell the whole charging infrastructure shebang with on-site storage and likely a decade or two contract with recurring costs and fees.


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## remy_martian (Feb 4, 2019)

The economics were predicated on the 4680 cell.

The Semi was delayed by the 4680 cell, as was Cybertruck.

The range was always cited as 300-500 miles. Nobody is disputing it went 500 miles at gross weight. What's in question is the PAYLOAD (the moneymaker).

Volvo, Daimler, and others were eating Tesla's lunch for the past couple of years with EV semi offerings. BYD now has one as well.

The Semi's battery was reworked to use the more expensive 2170 cells.

Tesla's in trouble if they don't get their act together on the 4680. All they have is a "me too" that's late to the party against companies with established service centers. There is no magic in any of this. Daimler has a wind tunnel here in Portland -- as if aero was some kind of innovation that gives Tesla a leg up? Puhleez.

The charger is nothing special - they are and have been available from others...in fact, it HAS to be standardized at loading docks, which is when regional trucks charge.

Tesla's only calling card is self-driving, which doesn't work yet and is no better than Daimler's.

They are severely late to the party. They are running on pricing (now forward pricing) based on 4680. Either they raise the price, or the 4680 goes in. Again, that special sauce ain't there, so this is just a "me too" product with a mouthpiece CEO who's been caught lying and stretching truth as a habit.


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## brian_ (Feb 7, 2017)

Electric Land Cruiser said:


> They can sell them for $200k because they aren't just going to sell a truck. They are going to sell the whole charging infrastructure shebang with on-site storage and likely a decade or two contract with recurring costs and fees.


Perhaps. Of course, we have no idea what they are actually selling them for, since they only have one customer so far, with a negotiated price which is likely confidential.


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## remy_martian (Feb 4, 2019)

Allegedly $150k starting price: Tesla Semi prices released, orders open in the US

Which seems awfully low as compared to a Model X.


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## brian_ (Feb 7, 2017)

The most interesting bit of information that I have seen from this great unveiling and the associated demonstration trip appeared in an article from electrek:
Watch Tesla Semi do something Bill Gates said wasn’t possible
It presumably came from one of Tesla's videos, but I haven't bothered to watch all the way through them, and it shows the battery state of charge over the famous 500-mile drive:








The state of charge drops in a very nice straight line, at 0.186 %SoC per mile; the steep climbs cause dips below that line, but lower consumption and regeneration on the complementary descents bring it right back to that line. The conclusion is that - at least for this vehicle driven this way (relatively steady speed) - grades don't matter to energy consumption per distance travelled. Note that the trip starts and finishes at essentially sea level.

Google Map route


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## Electric Land Cruiser (Dec 30, 2020)

There was a time on internet forums where if you participated in the discussion without having viewed the source material you would be chastised by others.

Now people freely proclaim their ignorance about not having viewed the source material and jumping in anyway.

Yes that graph was shown along with others. It's not surprising to anyone with EV experience; what goes up must come down. Hills along the way don't really hurt the overall range. The most important thing is the beginning elevation compared to ending elevation.


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## brian_ (Feb 7, 2017)

There was a time when "source material" wasn't both infinite in volume and nearly devoid of value. There was a time when corporations released rational information, instead of videos of chatter, so that a graph didn't need to be extracted from a video. And I linked to the source of the graph on which I was commenting, which is a reputable publication; as usual, my contribution here is far more rigorously backed up and clearly presented than most of this forum's content, so I don't see the need for the shot.

I did later skim through the official Tesla video and confirmed that it is the source of the graph, as expected. 

The "up-and-down equals level" effect is not so clearly true. Cycling energy through the powertrain and battery is far from perfectly efficient, so the net effect is not a wash - the result here is good, but that can't be assumed. The efficiency of any powertrain varies with load, so the average efficiency of high power on the climb and low power on the descent can't be assumed to be the same as constant power for the same time - in this case switching between three motors on the way up and one motor on the way down is probably very helpful.


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## Electric Land Cruiser (Dec 30, 2020)

brian_ said:


> There was a time when "source material" wasn't both infinite in volume and nearly devoid of value. There was a time when corporations released rational information, instead of videos of chatter, so that a graph didn't need to be extracted from a video. And I linked to the source of the graph on which I was commenting, which is a reputable publication; as usual, my contribution here is far more rigorously backed up and clearly presented than most of this forum's content, so I don't see the need for the shot.
> 
> I did later skim through the official Tesla video and confirmed that it is the source of the graph, as expected.


Yes, devoid of value  Luckily for you Tesla posted an edited down 35 minute version on their Youtube channel.

I don't really know anything about semis but here are a couple things that popped out to me from watching the Tesla event myself and then reading this thread:

-The Tesla semi uses a 1000+ volt architecture while the other EV semis use lower. Daimler comes close at "800-900." More voltage is an efficiency advantage, especially on a vehicle like this that will pull massive amps on a regular basis.

-Tesla designed a semi from the ground up whereas the legacy brands adapted their existing engineering that is really still 60s technology for the most part. They still have "fuel tanks" on the sides under the steel cab with fiberglass wind deflector for instance. There are benefits to doing it both ways. A cheap EV truck to move smaller trailers around a yard or make local deliveries might not need to be super advanced but obviously due to the technical challenges a long-haul EV semi does need to be super advanced. 

-It's a 4WD truck standard with advanced traction control. Your comments about it being bad in winter conditions is pretty telling. In the event, they did spend some time talking about winter conditions and how the semi has advanced traction and stability control to prevent jackknifing and other things. They said "it drives like a Tesla" because Teslas are famed for their winter performance and traction control. The open differential matters less with traction control using the normal disc brakes and single motor modulating, the rear axle should be able to torque vector and use disc brakes, both axles can be driven independently. Also the boost motors are able to connect and start providing torque before the cruise motor reaches full power when the driver puts their foot down as stated in the event. The 4WD should be able to seamlessly activate whenever needed or the driver can just turn it on for snow. Now heater performance and range in winter, that's another thing entirely.

-The brakes barely ever get warm due to regen, as to be expected but that is a massive benefit to truckers not having to let their brakes cool or check them. They have to pull over and get out of the truck and inspect etc. I've seen semis with their brakes literally on fire coming down I-70. A few years ago a run away semi killed several people after he lost control coming down from 9000ft into rush hour traffic. Not having to shift through the gears and change axle ratios etc is a massive improvement for driver fatigue as well. Much less brake pad dust in the environment longer service intervals.

-Yes, any EV truck will suffer a max payload penalty. But most trucks are not running at their max capacity or anywhere close. I don't think you can fit enough potato chips in a semi to hit 80k. Maybe if it's full of Pepsi. The Semi has an estimated 11,000 lbs of battery which definitely takes a chunk out of payload but in a lot of cases that doesn't matter. 

-Advances in technology like going to super single rear tires instead of dualies and aluminum trailers can tip the scale back towards an EV. For instance the Kenworth EV semi uses dualies and the Tesla semi uses big singles. The big single tires can save 1000 lbs by themselves. It's the sum of the parts coming together that make the end result significantly better than each small change can do on it's own.

-Average diesel semi engine/trans is 5000lbs

EV Semi +11,000lbs battery
-1000lbs aluminum wheels/tires
-2000 aluminum trailer
-1000lbs aluminum cab
= 7,000lbs net

EV truck 2,000lbs gross weight bonus = 5,000lbs net. Payload capacity unaffected. Obviously these are napkin level calculations for the purpose of discussion.

-Battery tech at launch is usually updated quickly by Tesla. I'm not a fanboy by any means but their track record shows. They upgrade batteries in first gen Model S and Roadsters for a really great price.

-In the delivery event livestream they showed their semi supercharger infrastructure. They spent several minutes showing acres of backup battery storage to deliver to Pepsi and Frito-Lay for their locations. It looked like Elon had batteries coming out of his ears he has so many.

-Elon said that Tesla will guarantee lifetime 7 cent/kwh Semi Supercharging and they will go 1,000,000 miles. The youtube channel below calculated that would be $180,000 for electricity vs. $700,000+ of diesel at current prices for 1,000,000 miles. It's unclear if the battery itself will go 1mn miles or just the chassis and drivetrain. I doubt the battery can come close but I bet it lasts about the same amount of time as an engine needs before it's time for an overhaul.






Like I said I'm no Tesla fanboy and do not like their marketing vaporware and anti-right to repair stuff like Rich Rebuilds is famous for but Tesla's track record is pretty good otherwise. I think EV makes more sense in a lot of cases for larger vehicles than small ones simply because a larger vehicle can carry more batteries. I also hate sitting behind two semis trying to pass eachother for 5 minutes on the interstate and I hate the smell of diesel.



> The "up-and-down equals level" effect is not so clearly true. Cycling energy through the powertrain and battery is far from perfectly efficient, so the net effect is not a wash - the result here is good, but that can't be assumed. The efficiency of any powertrain varies with load, so the average efficiency of high power on the climb and low power on the descent can't be assumed to be the same as constant power for the same time - in this case switching between three motors on the way up and one motor on the way down is probably very helpful.


There are a couple of advantages because of air resistance on a large vehicle like a semi it's better to drive at a slower speed and regen more vs. on a smaller EV to allow the car to accelerate with gravity and regen less. If there was no aero drag or safety issue it would be most efficient to just let the vehicle coast all the way down hills as fast as possible and then slow as you go up the next hill or use the speed to carry you are far as possible til you need to add power. Speed limits, traffic, and aero drag tip the scales towards driving 55 and regening. The 1000 volts also likely helps a lot in the losses of cycling the battery. Either way I know from my time commuting in an EV that the hills and ups and downs didn't matter anywhere near as much as the starting and ending elevations.


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## remy_martian (Feb 4, 2019)

Let's review what you wrote, with my notes at ###

-The Tesla semi uses a 1000+ volt architecture while the other EV semis use lower. Daimler comes close at "800-900." More voltage is an efficiency advantage, especially on a vehicle like this that will pull massive amps on a regular basis.

### The motors used in the Semi are the exact same ones used in the Plaid. Not even half the voltage your "1000+ volt architecture" argument makes. So, all that efficiency argument you are making is BS. They are likely "doubling series, halving parallel" in a 900V charging configuration. Daimler, I believe, uses an actual 800V motor, so your argument of who has the more efficient driveline gets reversed.

-Tesla designed a semi from the ground up whereas the legacy brands adapted their existing engineering that is really still 60s technology for the most part. They still have "fuel tanks" on the sides under the steel cab with fiberglass wind deflector for instance. There are benefits to doing it both ways. A cheap EV truck to move smaller trailers around a yard or make local deliveries might not need to be super advanced but obviously due to the technical challenges a long-haul EV semi does need to be super advanced.

### Tesla designed nothing from the ground up anymore than anyone else did. Everyone uses a motorized axle. Everone uses a 'glass body on truck frame. Everyone uses underslung battery packs. Arguably, Tesla puts their batteries behind the cab to get that extra range...ever notice the armored rack behind a semi's cab? It's to keep a load shift from spearing the cab...genius place to put a battery that lights up when you puncture it. CG-wise, the tractor will also be more prone to flipping in curves.

-It's a 4WD truck standard with advanced traction control.

### this is called a "full tandem" configuration, which has been available in your great grandfather's day.

Your comments about it being bad in winter conditions is pretty telling. In the event, they did spend some time talking about winter conditions and how the semi has advanced traction and stability control to prevent jackknifing and other things.

### Which is pure Musk bullshit. A jackknife occurs when the trailer tries to pass the tractor. The only thing traction control will do it align the trajectory of the tractor with the trailer to force the tractor into a wall or over a cliff.

They said "it drives like a Tesla" because Teslas are famed for their winter performance and traction control. The open differential matters less with traction control using the normal disc brakes and single motor modulating, the rear axle should be able to torque vector and use disc brakes, both axles can be driven independently.

###more nonsense. If the goal was real traction control, they would not have cheaped out on deleting that second motor on the single motor axle. This is typical for Tesla - they cheap out in stupid areas, imo.

Also the boost motors are able to connect and start providing torque before the cruise motor reaches full power when the driver puts their foot down as stated in the event. The 4WD should be able to seamlessly activate whenever needed or the driver can just turn it on for snow. Now heater performance and range in winter, that's another thing entirely.

### there's no sleeper, so warming the cabin is a piece of cake compared to even a sedan with a lot of glass that includes its roof.

-The brakes barely ever get warm due to regen, as to be expected but that is a massive benefit to truckers not having to let their brakes cool or check them.

### you have ZERO regen for the top 100kWh of charge. Zero. The regen argument applies for Volvo, Daimler, BYD, and others' trucks as well. Meh.

They have to pull over and get out of the truck and inspect etc. I've seen semis with their brakes literally on fire coming down I-70. A few years ago a run away semi killed several people after he lost control coming down from 9000ft into rush hour traffic. Not having to shift through the gears and change axle ratios etc is a massive improvement for driver fatigue as well. Much less brake pad dust in the environment longer service intervals.

### there is no low gear at the top of SoC. There is no low gear. You HAVE to ride the brakes down the hill in that case. And stop to cool them down before they fade to zero.

-Yes, any EV truck will suffer a max payload penalty. But most trucks are not running at their max capacity or anywhere close. I don't think you can fit enough potato chips in a semi to hit 80k. Maybe if it's full of Pepsi. The Semi has an estimated 11,000 lbs of battery which definitely takes a chunk out of payload but in a lot of cases that doesn't matter.

### Tesla has carefully chosen its battle. You are absolutely correct about potato chips, styrofoam MacDonalds cups, etc as loads. Again, applies to all electric semis

-Advances in technology like going to super single rear tires instead of dualies and aluminum trailers can tip the scale back towards an EV.

### Tech that's been in use in Europe and ROW forever.

For instance the Kenworth EV semi uses dualies and the Tesla semi uses big singles. The big single tires can save 1000 lbs by themselves. It's the sum of the parts coming together that make the end result significantly better than each small change can do on it's own.

### Tires and wheels are build options for the other EV semis

-Average diesel semi engine/trans is 5000lbs

EV Semi +11,000lbs battery
-1000lbs aluminum wheels/tires
-2000 aluminum trailer
-1000lbs aluminum cab
= 7,000lbs net

### you don't get to pick the trailer, especially when much of the freight out there is modular and uses sea containers

EV truck 2,000lbs gross weight bonus = 5,000lbs net. Payload capacity unaffected. Obviously these are napkin level calculations for the purpose of discussion.

-Battery tech at launch is usually updated quickly by Tesla.

###battery tech was supposed to be the cheaper 4680. Look for a price increase or profuse bleeding of cash if they hold pricing.

I'm not a fanboy by any means but their track record shows. They upgrade batteries in first gen Model S and Roadsters for a really great price.

-In the delivery event livestream they showed their semi supercharger infrastructure. They spent several minutes showing acres of backup battery storage to deliver to Pepsi and Frito-Lay for their locations. It looked like Elon had batteries coming out of his ears he has so many.

### Batteries WAS a Tesla strength. This will change in 2-3 years. Tesla had NO batteries for the semi -- they had to redesign the pack to use more expensive Model 3 batteries. Chargers from BYD and Proterra have been out there for a while using reverse pantographs, which don't seem possible with Tesla's cab design.

-Elon said that Tesla will guarantee lifetime 7 cent/kwh Semi Supercharging and they will go 1,000,000 miles.

### Musk has made many promises on the cars he has taken back. He's a carny, a pitchman, a barker.

The youtube channel below calculated that would be $180,000 for electricity vs. $700,000+ of diesel at current prices for 1,000,000 miles. It's unclear if the battery itself will go 1mn miles or just the chassis and drivetrain. I doubt the battery can come close but I bet it lasts about the same amount of time as an engine needs before it's time for an overhaul.

###If the motors are geared down as I suspect, using the 20,000 RPM Plaid motor was a mistake for longevity, imo. Tesla was renowned for not getting more than 100k miles out of Model S drive units. Semis run long days, many miles, and a diesel is low RPM...which is why it lasts longer.

###So there you go - I've intentionally taken the counterpoint here to get the collective opinion to settle to reality, vs fanboy and shareholder hype. There are great attributes common to all EV semi trucks. There are also silly, car-guy, design choices that were made, much like was done with Cybertruck. Yes, Semi will haul bags of potato chips 500 miles...and getting speared in your truck cab by a Dorito is unlikely.

### I've been busy lately, but I think there's a Youtube video on this that's topical. I'll screen it first and if worthwhile, will reference it in this thread.


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## brian_ (Feb 7, 2017)

Electric Land Cruiser said:


> ... If there was no aero drag or safety issue it would be most efficient to just let the vehicle coast all the way down hills as fast as possible and then slow as you go up the next hill or use the speed to carry you are far as possible til you need to add power. Speed limits, traffic, and aero drag tip the scales towards driving 55 and regening.


I agree. Regen to control speed on descent is the practical approach; it incurs an efficiency loss, but still works out well.


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## brian_ (Feb 7, 2017)

The Tesla delivery event was certainly successful with the target audience, convincing those who were inclined to favourable opinions - and largely unfamiliar with heavy truck design and operation - that a miracle had indeed been delivered. Of course, it had not... but they did deliver a perfectly good battery-electric truck.


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## brian_ (Feb 7, 2017)

I found the *three-motor powertrain* choice interesting. Like Rivian (which has disconnects for the rear axle shafts of the R1T), Tesla found that running one highly loaded motor was adequate for highway cruise, and more efficient than running three or four similar motors, each lightly loaded. The efficiency difference with load isn't surprising (you can see it in the efficiency map of any motor), but I find it interesting that just one motor is enough, and that the efficiency difference is enough to justify the cost and complication of the disconnects. By the way, at least in smaller sizes, those disconnects are common off-the-shelf components.

The original (five years ago) publicly displayed prototype used dual motors on each axle, but the gear reduction ratio was different between the axles, so they had apparently intended even then to operate on the motors in only one axle under some conditions. I don't recall seeing any references to physical disconnects at that point, but they may have been included. The disconnects may also have been added after Rivian demonstrated their application.

The conventional equivalent is that trucks with tandem rear axles have been routinely available in three configurations:

*6X2*: only one rear axle (generally the leading one) is driven; the other one is a "pusher" (ahead of driven axle) or "tag" behind driven axle) and may have single tires (or smaller super-singles if the drive axle has wide-base singles). Tag and pusher axles can have castering wheels (self-steering). A common intercity coach (bus) is a 6X2 with tag axle.
*6X2/4*: only one rear axle (the leading one) is driven; the other one is engaged only when required for traction. Since the two axles will "fight" causing destructive and energy-consuming tire scrubbed the second axle is left disengaged as much as possible. This is functionally like a traditional part-time 4WD system, in which one axle (traditionally the front) is engaged only off-road. _The Tesla Semi is essentially doing this, but due to the separate motors for each axle scrub is not an issue._
*6X4 with inter-axle differential*: both axles are driven at all times, by the two outputs of an inter-axle differential which is mounted on the leading axle. The inter-axle differential may be lockable, just as the centre differential in a 4X4 may be lockable. An electric truck with motors on each axle is equivalent, but doesn't need a mechanical inter-axle differential or lock because the motors can run at different speeds and can be controlled to run at the same speed.
Some current heavy battery-electric trucks (such as those from Volvo/Mack) use a motor (or two on a shared transmission) mounted to the frame and conventional mechanically driven axles. Others (such as those from PACCAR) use axle-mounted motors like Tesla. I have not seen any indication of their motor management scheme, meaning how many motors they use under what conditions.


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## brian_ (Feb 7, 2017)

The weight comparisons between the Tesla Semi and diesel trucks in online discussions can be very frustrating. Almost no one makes a rational comparison, which means

accounting for all major components, meaning
battery, motors, gearboxes, and supporting equipment (charger, cooling, etc) for the EV
fuel, engine, transmission, driveline, and supporting equipment (exhaust, cooling, etc) for the diesel

comparing similar configurations, which means tandem-drive Class 8 day cabs
assuming comparable options (e.g. everyone uses aluminum wheels now; if one has wide-base single tires then other should, too)
using the same trailer, if considering trailer weight
For a very rough example:

EV with 1 MWh battery: 5,000 kg (11,000 lb) battery + motors, gearboxes, and supporting equipment (charger, cooling, etc)
Diesel: 2,000 kg engine + 300 kg fuel + transmission, driveline, and supporting equipment (exhaust, cooling, etc)
If the diesel's transmission weighs about the same as the EV's motors and gearing, and the diesel's exhaust system (with DPF and SCR) weighs about the same as the EV's charger, etc, and both have cooling systems, then the EV is 2,700 kg (a few tons) heavier; there is a huge uncertainty in that value.

Tesla likely compares their day cab to a typical diesel sleeper cab to conclude that the difference is only one ton of extra weight allowed by U.S. federal highway standards. It helps to get this deception accepted that the 500-mile (larger battery) version of the Semi has a cab extension that looks like (but is not) a sleeper.

The delivery video shows (at 16:47, if I recall correctly) a much-discussed example load behind a Tesla Semi, consisting of eleven roughly 10-foot concrete road dividers (called "jersey barriers"). A much-quoted estimate assumes 4,000 pounds per barrier (that's at the light end - many are substantially heavier) plus a 10,000 pound flat-deck trailer for a total of 54,000 pounds. Subtract that from the 81,000 pounds stated for a different Semi with a different trailer (!) and you get a 27,000 pound tare weight for the Semi tractor. There are so many rough estimates and questionable assumptions that this is very approximate, and more likely a high limit than an expected value (because of the light barriers and implausibly light trailer). That's higher than needed (based on component weights), but only about a ton heavier than the heavy end of sleeper-equipped diesel highway tractors.


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## remy_martian (Feb 4, 2019)

This carries an extreme anti-Musk sentiment and is hypercynical, but has some interesting points of view, nonetheless:






For the unfamiliar, he's been calling out Musk for years on his channel.

edit: He does go through some of the weight analysis Brian posted while I was posting this one.


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## Electric Land Cruiser (Dec 30, 2020)

brian_ said:


> The Tesla delivery event was certainly successful with the target audience, convincing those who were inclined to favourable opinions - and largely unfamiliar with heavy truck design and operation - that a miracle had indeed been delivered. Of course, it had not... but they did deliver a perfectly good battery-electric truck.


Is anyone here saying it's supposed to be anything more than a perfectly good battery electric truck? People are saying it's worse, definitely....


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## electro wrks (Mar 5, 2012)

Here's my Semi weight analysis from 2017, when the Semi was first introduced:

"The Tesla Semi main designe_r, _Jerome Guillen, said in a recent presentation in Europe that the Tesla truck weighs no more than a diesel truck. If you take a modern diesel semi (also designed by a team lead by Jerome Guillen when he worked for Daimler/ Freightliner) and pull the engine:DD16® | Freightliner Trucks ; transmission:https://freightliner.com/demand-detroit/detroit-dt12-transmission/ say ~1000# of tanks, radiators, non-fuel fluids, and other ICE related equipment; and 200gal(~1400#) of fuel. You save ~6000# (if I haven't left any thing out). So how much energy will ~6000#(~2700kg) of batteries give us? "

I wonder how close to the finished product I got.


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## remy_martian (Feb 4, 2019)

I bet the electric air compressor for the brakes on an EV semi is pushing 200 pounds.

The entire engine bay of the eCascadia I saw about a month ago was completely filled with stuff, despite the humongous inverter boxes, motors, and batteries being mounted elsewhere.

Everything seemed to be mounted on heavy steel weldments. The truck builders understand longevity and everything was built like a brick poophouse on that truck - Tesla is using high-strung car motors, and I'm guessing with none of that margining. The cab is aluminum, so what else is for lightweighting? Aluminum cracks under fatigue...

I lost faith in Tesla's truck sensibilities after the Cybertruck abomination. How do you carry bales of hay with it or even load it from the side?

(my pic):


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## brian_ (Feb 7, 2017)

Electric Land Cruiser said:


> Is anyone here saying it's supposed to be anything more than a perfectly good battery electric truck? People are saying it's worse, definitely....


Here? No. But here the participants in the discussion are generally knowledgeable about the reality of battery-electric vehicles.
The Youtube and Facebook (and presumably Twitter, if that system is still operating ) comments have the usual Musk disciples spouting nonsense.


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## brian_ (Feb 7, 2017)

electro wrks said:


> Here's my Semi weight analysis from 2017, when the Semi was first introduced:
> 
> "The Tesla Semi main designe_r, _Jerome Guillen, said in a recent presentation in Europe that the Tesla truck weighs no more than a diesel truck. If you take a modern diesel semi (also designed by a team lead by Jerome Guillen when he worked for Daimler/ Freightliner) and pull the engine:DD16® | Freightliner Trucks ; transmission:https://freightliner.com/demand-detroit/detroit-dt12-transmission/ say ~1000# of tanks, radiators, non-fuel fluids, and other ICE related equipment; and 200gal(~1400#) of fuel. You save ~6000# (if I haven't left any thing out). So how much energy will ~6000#(~2700kg) of batteries give us? "
> 
> I wonder how close to the finished product I got.


With what is likely 11,000 pounds (5,000 kg) of battery, and the pesky little details of electric motors, reduction gearboxes, inverters, etc. the "500 mile" Tesla Semi will be substantially heavier than a truly comparable diesel truck, because that "~6000#(~2700kg) of batteries" isn't enough. But we are all still wondering, because Tesla won't say what the Semi weighs.

With only 60% of that amount of battery, the "300 mile" Tesla Semi would have about 6,600 pounds (3,000 kg) of battery, and come closer to the "same weight", but still needs the 2,000 pound exemption that U.S. federal rules allow.

The biggest available diesel engine may be a reasonable choice if the basis of comparison is power, but few if any buyers would spec that engine for an ordinary highway tractor at only 80,000 gross weight; this is minor factor, since the more appropriate DD13 is only 20% lighter. Also, there's no need to burden the diesel with 200 gallons of fuel when it only needs 75 gallons for 500 mile range.


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## electro wrks (Mar 5, 2012)

brian_ said:


> With what is likely 11,000 pounds (5,000 kg) of battery, and the pesky little details of electric motors, reduction gearboxes, inverters, etc. the "500 mile" Tesla Semi will be substantially heavier than a truly comparable diesel truck, because that "~6000#(~2700kg) of batteries" isn't enough. But we are all still wondering, because Tesla won't say what the Semi weighs.


At the time of this analysis in 2017, some of us were thinking the battery energy density would have to improve by a factor of ~2X for the 500 mile range Semi to have the same weight as its diesel counterpart. It will be interesting to see what the actual weight is.


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## brian_ (Feb 7, 2017)

That first half of the "Thunderf00t" video was an enormous waste of time, raising nothing other than the obvious (the product is late, the truck's tare weight is not stated, and FSD is a farce), and the weight analysis is laughably wrong. He is correct that the trucking industry does not care about acceleration or grade-climbing speed the way Tesla seems to, and that autonomous operation is still not ready. At the end he returns to the obvious - that range is limited and charging takes time, and that while Tesla has stalled real truck manufacturers have put battery-electric trucks in production for appropriate applications. In my opinion, the nonsense drowns out the intelligence.

In the demonstration drive the Tesla Semi doesn't pass anything, simply because the driver is maintaining a relatively constant and moderate speed, as it must for sufficient range. 

Check the comment by Doggfite on that YouTube video for an explanation of the multiple errors in Thunderf00t's weight nonsense. For a simpler check, note the barriers are most of the length of the vehicle passing the trucks - it's not a Smart ForTwo so those are not 2 metre (6 foot) barriers on the truck.


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## cricketo (Oct 4, 2018)

Fun Tesla Semi video here :









Tesla on LinkedIn: Our engineers tested Semi in a variety of harsh conditions to maximize… | 127 comments


Our engineers tested Semi in a variety of harsh conditions to maximize reliability & durability. Join us on the Vehicle Test Team. https://lnkd.in/gu2NPePh | 127 comments on LinkedIn




www.linkedin.com


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## electro wrks (Mar 5, 2012)

Here's one recent estimate of the weight and battery capacity of the Semi: https://www.teslarati.com/wp-conten...Shot-2022-12-29-at-9.01.43-AM-2048x1142-1.jpg
If correct, this is in line with what some of us figured in 2017, as outlined in posts 44 and 48. It's too bad that Tesla was not able to keep the tractor weight down(again, if this is correct) to that of its diesel powered counterparts, as claimed at the time of the Semi's introduction. The Semi still appears to be as good or better than its competitors. This weight factor will only improve over time, with better batteries. Overall, it remains to be seen how well this radical shift in technology will be accepted into the very competitive trucking industry.


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## Electric Land Cruiser (Dec 30, 2020)

That is actually lighter than a lot of people predicted for the Tesla semi. A lot of people thought it would be 30k or more. Some diesel semi tractors are 20-25k lbs also.

Lastly the weight is less important I read a stat that based on data 90% of trucks on the roads in the USA are 73,000 or less. They are not always fully loaded which was my previous suspicion. Of course it won't replace every semi but definitely a good amount.


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## remy_martian (Feb 4, 2019)

It's just a matter of time before Musk gets accused of unfair trade practices (battery dumping) by his competitors, if those price estimates are correct. 

There's no magic in this stuff that cuts prices in half...


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## brian_ (Feb 7, 2017)

electro wrks said:


> It's too bad that Tesla was not able to keep the tractor weight down(again, if this is correct) to that of its diesel powered counterparts, as claimed at the time of the Semi's introduction. The Semi still appears to be as good or better than its competitors.


I don't remember the details of the original fantasy, but Tesla has recently claimed that the Semi would be heavier than "a diesel truck" by only the extra 2,000 pounds allowed under U.S. federal rules for highway vehicles, giving them the same payload. Now, what is "a diesel truck" and what are "its competitors"?



Electric Land Cruiser said:


> Some diesel semi tractors are 20-25k lbs also.


Yes, but what tractors? Day cabs with only 80,000 pound gross weight ratings? Not likely. We probably have lots of highway tractors here at that tare (curb, empty) weight, but they have sleeper cabs and are equipped and used for Super B-Train or dual 53-foot trailer service, with 63,500 kg (140,000 lb) combination weight rating. Comparing the Tesla Semi day cab to a diesel tractor with a large sleeper, or to a tractor capable of hauling much higher loads, doesn't make sense.

Heavy truck manufacturers generally do not publish the weights of their products online, even in downloadable brochures and guides, presumably because the weight can vary so much with the many configuration options offered. Tesla doesn't share any real information at all. This makes objective comparison extremely difficult. It would be interesting if there were a real journalist anywhere in the automotive world who would assemble a Tesla Semi some truly comparable tractors, and run them all through scales to get real information. That's not going to happen any time soon, but we can hope that a Pepsi driver takes a Semi through a scale without a trailer and shares the weight.


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## brian_ (Feb 7, 2017)

electro wrks said:


> Here's one recent estimate of the weight and battery capacity of the Semi: https://www.teslarati.com/wp-conten...Shot-2022-12-29-at-9.01.43-AM-2048x1142-1.jpg


That appears to be from the Teslarati "news" item _Tesla Semi outperforms rivals in specification analysis_, and repeats material published by NextBigFuture as _Shopping Guide for Electric Semi Trucks [Prices, Weights and Payload]_.
That author provides no sources. We know that Tesla does not provide any weight data, so those values are guesses; I wonder if they're all guesses?

I note that there are two Freightliner eCascadia configurations listed with the same battery capacity, essentially the same range, the same price... and yet two significantly different weights (one 16% or 3050 pounds heavier). The heavier eCascadia has less power and lower GCWR, suggesting that it might be a straight truck rather than a tractor; if so, the comparison table is nearly useless. I applaud the effort, but there isn't enough information here to seriously compare anything.

I also note that the Tesla Semi 300 and the lighter variant of the Freightliner eCascadia are quite comparable in weight (the Tesla has 16% higher guessed battery capacity and 9% higher guessed weight). This isn't surprising; it also doesn't demonstrate any Tesla advantage. The claimed range of the Tesla is much higher in this pair, but all range values are of little value with no comparable basis for range determination.


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## brian_ (Feb 7, 2017)

electro wrks said:


> If better, more up to date info becomes available, by all means people should post it.


I agree; I will certainly share anything that I find which I think is valuable.



electro wrks said:


> For now, this is what is available. Should I take it down because it is not perfect?


That's not what I intended at all. I appreciate the link to the material which is available, although I wish the originator had provided sources or explanations of the numbers, which would have given them more value. I do think it is important to distinguish data from estimates.


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## brian_ (Feb 7, 2017)

Electric Land Cruiser said:


> Lastly the weight is less important I read a stat that based on data 90% of trucks on the roads in the USA are 73,000 or less. They are not always fully loaded which was my previous suspicion. Of course it won't replace every semi but definitely a good amount.


While mass is important to energy consumption, I agree that legal truck weight limits are not as major a limiting factor as many people think. Trucks are often limited by the bulk (volume) of the load rather than the weight (called a "cube-out" situation), or simply to the size of what needs to be moved as one shipment. 

Suiting the truck to the application is important. While the Teslarati article ignores this (because their purpose is to rationalize a declaration of Tesla superiority), the _NextBigFuture_ article which is the source of all of their information copies and links to a rational discussion from Freightliner: _Moving the Electric Needle: Smart Ways to Use Electric Trucks_

Most rational EV applications in trucking are in anything but long-haul, and most are for straight trucks rather than tractors pulling semi-trailers. Tesla has only addressed the tractor-trailer application, presumably either because they think that it is the most impressive to their fans, or because they don't want to deal with upfitters (the companies that add second-unit bodies and equipment to base trucks to make them useful).


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## remy_martian (Feb 4, 2019)

Meanwhile, Ian Wright, one of Tesla's founders (pre-Musk), went the other way and founded a company that builds electric trucks (not semis) at Wrightspeed.


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## electro wrks (Mar 5, 2012)

brian_ said:


> That author provides no sources. We know that Tesla does not provide any weight data, so those values are guesses; I wonder if they're all guesses?


Or, they might not be. Maybe the author called around to the electric truck manufacturers, with a reporter's verve, asking them to confirm or deny performance specs of their trucks. Or, maybe he told them he was going to publish some arbitrarily unflattering figures for the specs, forcing them to cough-up the actual specs.


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## brian_ (Feb 7, 2017)

electro wrks said:


> Or, they might not be. Maybe the author called around to the electric truck manufacturers, with a reporter's verve, asking them to confirm or deny performance specs of their trucks. Or, maybe he told them he was going to publish some arbitrarily unflattering figures for the specs, forcing them to cough-up the actual specs.


So we agree - we have no idea where these numbers came from. It would be good to know.
I did not claim that I had better information; I only distinguished between these numbers and real data.


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## MattsAwesomeStuff (Aug 10, 2017)

Just a note, I purged some personal squabbles from this thread. If you feel it was unfair, and these were beneficial to the community, PM me and we'll discuss it.


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## electro wrks (Mar 5, 2012)

brian_ said:


> I did not claim that I had better information; I only distinguished between these numbers and real data.


This does not make sense. If you claim to have "real data", then you must think you have "better information". This spreadsheet is what information, and yes assuming some errors, is out right now by one author. By all means, show us more correct and up to date information, if you have it. Or, better yet, do the research and make up a better spreadsheet.


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## brian_ (Feb 7, 2017)

electro wrks said:


> This does not make sense. If you claim to have "real data", then you must think you have "better information". This spreadsheet is what information, and yes assuming some errors, is out right now by one author.


Again (and again, and again...) I did not claim to have real data or better information. But thanks for confirming that this spreadsheet contains at least values which are not real data or confirmed information.

Matt, please feel free to delete this round, too...


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## brian_ (Feb 7, 2017)

A rational discussion of most of the interesting issues regarding the Tesla Semi, as an update of an earlier discussion:
YouTube by Jason of _Engineering Explained_: _Does The Tesla Semi Make Any Sense? Part 2!_

Sources and basis for values and calculations are provided. While there are minor issues, I generally agree with this analysis.


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## Electric Land Cruiser (Dec 30, 2020)

brian_ said:


> A rational discussion of most of the interesting issues regarding the Tesla Semi, as an update of an earlier discussion:
> YouTube by Jason of _Engineering Explained_: _Does The Tesla Semi Make Any Sense? Part 2!_
> 
> Sources and basis for values and calculations are provided. While there are minor issues, I generally agree with this analysis.


I said that the truck was driving at 55 mph or less for the journey.
I said that the up and down of mountains doesn't matter as long as the starting and ending elevation are the same.
I said that the deficit of the Tesla semi vs. a diesel would be about 5,000lbs.
I said that the majority of loads on the road are less than 73,000lbs.

I should have written it on a white board.


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