Tesla Electric Semi-Truck?

[GravitySucks]

Any idea how much this is going to cost a non industry guy like me in tax credits?

[MRG]

Quote:

Originally Posted by ERD50 OK, on the battery, my number look more like: The Tesla 85 kwh pack: 85kwh 600kg 141.67 wh/kg So assume ~ 1000 kwh battery in the semi: 1000 kwh truck batt 7,059 kg truck batt calculated 15,529 # That's about 15 thousand pounds of battery pack. That's a big chunk (~ 19 %) of the 80,000 # max gross weight allowed in the US. Though I'm not sure if most deliveries are limited by weight or size of cargo? Anyone want to take a stab at engine/trans/related weight versus electric motor weight? I'm guessing the delta won't come close to that 15,000 # delta of battery versus 77 gallons of fuel @ ~ 7#/G ~ 540#. Plus the tank weight, battery weight includes the pack , but then again, 15,000 # will require some support as well. -ERD50

The 80,000 lb limit is just a suggestion😂.

I think it depends what your hauling, sand or Styrofoam?

Two real points. Seven miles to the gallon is optimistic. Please give me more fuel, I don't want to bleed the system.

Here's some data on engine weight. Of course you need another 1500 lbs for a transmission. ETA: Four electric motors? Don't know about newer technology but the 100hp 3phase electric I worked around in the 70's was very heavy. There was a lot of copper in there.

As expected, engines in semi-trucks are huge, and they need to be in order to move all of the trailer weight. The Detroit Diesel DD15 is a semi-truck that boasts a 14.8-liter inline six-cylinder diesel engine that weights 2,880 lbs. This big engine isn’t built to provide a semi-truck with horsepower, as it only generates 506 horsepower, but rather to provide torque.

Torque is what helps semi-trucks tow all of that weight behind them. So for this specific truck to carry 80,000 lbs, it needs to generate 1,850 lb-ft of torque—sometimes even more to keep the weight moving and all 18 wheels turning. The fuel tanks inside these semi-trucks are massive in order to combat the weak fuel economy.



http://www.autotraining.edu/blog/the...f-18-wheelers/

[jazz4cash]

Hey I already spend way too much time on the seeking alpha TSLA site where there are 4 articles every day with hundreds of comments each so here's my 2 cents....
It's tough for me to discus Musk
without making comments that should (but won't) bring porky to this thread. I'll leave it at Evil Genius.
City stop and go duty cycles need electric vehicles way more than long haul. It would be much easier for Tesla to go into that market with their current system so I can't fathom why they want to jump all the way to big rigs. The Model S,X, and 3 have issues that would seem to need 100% focus. Oh then there s Roof, Powerwall, SpaceX, Solar City, and Tunnels. Maybe Hyperloop. None are meeting expectations set by Musk. Autopilot is one feature I do believe would be attractive to the semi-truck market, but I believe that feature also has a long way to go.
I was an applications engineer for heavy truck components. You all have done a good job summarizing the challenges to produce an electric semi. I could give you dozens of reasons why the market for class 6,7 electric trucks is way better and easier to implement.

[ncbill]

Quote:

Originally Posted by ERD50 The numbers there seem way off, and are not apples-apples. First, comparing 500 mile range, at 6.5 mpg for diesel, that is 77 gallons, a lot less than 300 gallons. They estimate 1 KWh per mile, but Tesla's site says < 2 KWh per mile. Safe to assume not much less, or they would have said ~ 1 KWh per mile. So off by almost a factor of 2x on battery size. Not sure about the weight comparisons, but you would also need to include the 4 electric motors in that. -ERD50

iirc, EV motors are only about 75 kg each.

Even if the battery pack weighs 5 tons, I don't see any real difference vs a traditional diesel power train.

It would be nice if Tesla would release full specs on the capacity/weight of its battery.

I'm more concerned about powering the "mega" chargers:

https://www.teslarati.com/tesla-semi...close-up-look/

[misanman]

At some point shouldn't these electric vehicles pay highway taxes? Seems like they are getting a "free ride".

[lwp2017]

Natural gas fueled large trucks are the future.

Electric trucks are uneconomical without a carbon tax credit to offset the battery cost.

[ocean view]

Quote:

Originally Posted by misanman At some point shouldn't these electric vehicles pay highway taxes? Seems like they are getting a "free ride".

No more free ride in CA. We just implemented a new gas tax to help fix the roads, adding 12 cents/gallon. At the same time EV drivers will now have a transportation surcharge added to their annual registration fee to cover their share. I don’t recall the amount, maybe $100 per year.

Have any other states done anything similar?

[rocketjockey]

Quote:

Originally Posted by jazz4cash Oh then there s Roof, Powerwall, SpaceX, Solar City, and Tunnels. Maybe Hyperloop. None are meeting expectations set by Musk. Autopilot is one feature I do believe would be attractive to the semi-truck market, but I believe that feature also has a long way to go. I was an applications engineer for heavy truck components. You all have done a good job summarizing the challenges to produce an electric semi. I could give you dozens of reasons why the market for class 6,7 electric trucks is way better and easier to implement.

I am not a semi truck applications engineer, but I AM an aerospace engineer who has work in the rocket launch biz for 20 years and counting, including several years for SpaceX.

Elon has a well known knack for overly optimistic schedules, but I would not bet against his success. In less than 15 years he has completely turned the rocket biz on its head. Unseated the longtime megacorp giants, sending them out of biz or forcing a massive scramble to try and catch up which will take decades if they pull it off. All from absolute zero. I myself laughed at SpaceX when they first came out, made fun of the amateur. Then they killed my company and I went to work for them.

Sure Tesla has piles of problems, but in just over 5 years, the have sold over 150K Model S alone. From "Who?" to outselling S-Class Benz, 7 Series BMW, A8 Audi, etc......

I might poke fun at his timing, but I would not bet against his long term vision.

[CaptTom]

Quote:

Originally Posted by ocean view No more free ride in CA. We just implemented a new gas tax to help fix the roads, adding 12 cents/gallon. At the same time EV drivers will now have a transportation surcharge added to their annual registration fee to cover their share. I don’t recall the amount, maybe $100 per year.

These types of taxes are ridiculous.

The roads benefit all of society, not just the car and truck owners. I'm not a fan of big government, but I have to admit there are a few things that we all benefit from if done centrally. Roads are among them.

You can argue (but please don't!) how to create a fair tax structure. But once that's decided, money for roads should come from those general tax revenues. Not just drivers and truck owners.

I'm not a big fan of tolls, for the same reasons, as well as highway safety, traffic jams and the creation of a new bureaucracy of toll collectors.

[mickeyd]

Quote:

Originally Posted by aja8888 I hope he comes out with a hand-held, battery powered device soon that can allow people to speak to each other through a coded numbering system! That would be cool!

Will it have to be hand-held?

[NW-Bound]

Large EVs have been around, though they do not have the publicity of this Tesla semi engine. A Chinese company called BYD has been making large articulated buses, garbage trucks, tractors, etc... for their domestic use. They have been pushing for sales in North America.

So, the question is not whether heavy EVs are technically feasible as they are well within the reach of today's technology, but how economically competitive they are. This will be interesting to watch.

By the way, Warren Buffett invested in BYD.

[ERD50]

I posted this a while back - I guess some testing is still going on, but not too much news. An electric delivery/garbage truck - limited range but a constant speed turbine keeps the batteries topped off. They get the benefit of regen braking, and they say the turbine is clean and meets future EPA requirements w/o any added stuff.

https://www.wrightspeed.com/technology

http://www.early-retirement.org/foru...ml#post1746288

-ERD50

[Chuckanut]

Interestingly, a few years ago I read an article by a former GM exec saying that electric vehicles made more sense in expensive low mpg type vehicles. More savings bang for the buck in a 50K and up vehicle that gets lousy mileage compared to cheap small car that gets 38 mpg. The big truck seems to fit right that to a 'T'.

Bob Lutz on Electrification of Pickup Trucks and VIA Motors

Of course, Mr. Lutz tends to change his mind from time to time. But, IMHO, a Model S or a fancy roadster makes more sense than the Model 3. The Model 3's biggest competitor will be hybrids like the Prius or the new 50+ mpg hybrid Camry. My 2¢.

Mr. Musk has a habit of under estimating the time and difficulty of his projects.
OTOH, if you want to get cargo up to the ISS and then take a meaningful amount back he has the only space craft that will do that. And, his rockets, while perhaps not super dependable yet, are cheap enough that they are worth the risk. Who else can land a first stage on a barge in the ocean and then reuse it? This is hardly the mark of a con-man, IMHO.

I suspect his subsidies are not worse than many others who get the 'gubmint' to pay part of their bill. Just give some thought to ethanol as fuel. Or sugar prices. Or bailed out banks. Etc. etc. etc.....

[NW-Bound]

Quote:

Originally Posted by ERD50 I posted this a while back - I guess some testing is still going on, but not too much news. An electric delivery/garbage truck - limited range but a constant speed turbine keeps the batteries topped off. They get the benefit of regen braking, and they say the turbine is clean and meets future EPA requirements w/o any added stuff. https://www.wrightspeed.com/technology http://www.early-retirement.org/foru...ml#post1746288 -ERD50

Yes. This idea of a hybrid car is not new, where propulsion is provided solely by an electric motor, whose battery is kept charged by a small combustion engine running at a constant speed. The current day version uses a high-tech turbine, but older prototypes used a small 4-stroke engine tweaked for efficiency at one constant speed.

I recall in the early 80s reading about Briggs & Stratton building such a concept car, because small 4-stroke engines were their specialty. It did not go anywhere, and I just now wonder if this company is still around.

Dug a bit better, and the same idea in that B & S concept car was implemented by a French company called Krieger, back in 1904! How about that?

PS. Yes, Briggs and Stratton is still in business. Sales in 2016 is $1.6 billion. I have not heard much about them, but then I have not been looking in the market for a lawn mower or anything that uses a small engine.

[ERD50]

Quote:

Originally Posted by NW-Bound Yes. This idea of a hybrid car is not new, where propulsion is provided solely by an electric motor, whose battery is kept charged by a small combustion engine running at a constant speed. ... .

I'm fascinated with this concept, so maybe I can fill in a few details.

The problem with a pure series hybrid ( as you say "propulsion is provided solely by an electric motor, whose battery is kept charged by a small combustion engine running at a constant speed") is that it does help efficiency to keep that engine at a constant speed. But while you cruise the highway at 65 mph, you have the losses of converting rotary motion to electric, and from electric back to rotary (maybe 10% loss each way?). Even worse if some of that is buffered by the battery (another ~15% loss in/out?).

So you also want to be able to couple that engine to the wheels directly when you can. Check out "Engineering Explained" on youtube. I think it is one of the new Hondas that runs in EV mode right up to highway speeds, and then the the ICE couples direct to wheels above ~ 35 mph - no transmission, always direct drive, just a clutch to disconnect the ICE from wheels at lower speeds.

Quote:

Originally Posted by NW-Bound ... The current day version uses a high-tech turbine, but older prototypes used a small 4-stroke engine tweaked for efficiency at one constant speed.

WrightSpeed uses a turbine, and from what I understand it is a low maintenance engine, which makes it attractive for a fleet operator. And meets emission rules w/o added stuff. But turbines are not as efficient as a piston engine, so it really needs the stop-start regen braking advantage to come out ahead, it won't cut it in long haul trucks (Ian Wright is very upfront about that).

But what is old is new again. Recently, I posted some links to Mazda's SC-HCCI engine.

edit/add: here is the link:

http://www.early-retirement.org/foru...ure-88129.html

A gasoline piston engine with the efficiency of a diesel. I think if this works out and is coupled with a strong hybrid, there is a real future for the old piston engine.

With those sorts of efficiencies, an SC-HCCI hybrid likely produces less pollution than the power plant output to charge an Electric Vehicle (even on a very 'green' grid). And no range anxiety.

-ERD50

[Scrapr]

Quote:

Originally Posted by ERD50 I posted this a while back - I guess some testing is still going on, but not too much news. An electric delivery/garbage truck - limited range but a constant speed turbine keeps the batteries topped off. They get the benefit of regen braking, and they say the turbine is clean and meets future EPA requirements w/o any added stuff. https://www.wrightspeed.com/technology -ERD50

I test drove one of Ian's delivery trucks at a conference several years ago. It was very cool. The sound of the turbine going was freaky. The motors on ea wheel were very small. I'd bet <50 lbs ea. I'd bet the weight of the turbine & motors on ea wheel were much less than engine + transmission.

I would have done one of his trucks but he wasn't ready for market. Last time I looked he was doing some garbage companies in the Bay.

Just looked at his site. Looks like he is focusing on Class 8 trucks and not the lower weights. He added a transmission instead of motors on ea wheel. Weight differential vs engine + transmission looks about even now

[ERD50]

Quote:

Originally Posted by Scrapr I test drove one of Ian's delivery trucks at a conference several years ago. It was very cool. The sound of the turbine going was freaky. The motors on ea wheel were very small. I'd bet <50 lbs ea. I'd bet the weight of the turbine & motors on ea wheel were much less than engine + transmission. I would have done one of his trucks but he wasn't ready for market. Last time I looked he was doing some garbage companies in the Bay. ...

That's cool! I've been very impressed with Ian when I've seen interviews. He was a co-founder of Tesla, for those who were unaware of that.

-ERD50

[Running_Man]

These electric vehicles with their environmental reputation are merely trading carbon emissions for lethal cobalt, nickel and lithium heavy metals into the environment which are destined to become a major problem. To manufacture the battery chemicals requires a whole body suit for production workers and all these metals are serious problems in a fire, which as the spread of these batteries occurs will eventually become known as cancers are spread by exposure to the heavy metals. If one looked at the SDS sheet for the chemicals going into a battery they’d never bring it into their house.

[ERD50]

Quote:

Originally Posted by Running_Man These electric vehicles with their environmental reputation are merely trading carbon emissions for lethal cobalt, nickel and lithium heavy metals into the environment which are destined to become a major problem. To manufacture the battery chemicals requires a whole body suit for production workers and all these metals are serious problems in a fire, which as the spread of these batteries occurs will eventually become known as cancers are spread by exposure to the heavy metals. If one looked at the SDS sheet for the chemicals going into a battery they’d never bring it into their house.

It is true that there are a lot of dangerous chemicals used in the battery production, but I have not seen anything that really breaks that down in terms of hazards to the public or environment.

But they are recycled, not just thrown about. Oil is a hazardous chemical as well. Do you have any sources that quantify the risks?

I'd like to know the same about solar panels. They use dangerous chemicals, and lots of energy in their production (the energy is paid back after about the first 2 years in the sun). They will need to be recycled in ~ 30 years, I'm not sure how green that is?

My more immediate concern is that EVs burn as about much/more fossil fuel than a good hybrid. But I think that's a different story for an EV versus diesel truck - those diesel trucks are dirty! I would expect an EV truck to have a real advantage there. Not so much with an EV car.

-ERD50

[6miths]

Quote:

Originally Posted by Ready I'm glad to see Elon is continuing to create new products, but it would be nice if he could figure out how to build more than a few Model 3's each week before venturing out into two new product categories.

+1