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Tesla Semi

Discussion in 'TSLA Investor Discussions' started by jhm, Jul 25, 2016.

  1. neroden

    neroden Model S Owner and Frustrated Tesla Fan

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    This is why I'm expcting the bankruptcy of the major oil companies. If demand drops massively, I don't think they can shrink fast enough to avoid bankruptcy.
     
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  2. Adm

    Adm Active Member

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    What if the battery is split between the truck and the trailer?
    The trailer will do part of the braking so it would need a motor too, if not for a part of the acceleration, than at least for regeneration of the enormous energy of the moving trailer.
    A trailer will spend time at a loading dock waiting for (un)loading. A great time to charge the battery.
    Just wondering: could regenerative braking replace the regular brakes of a trailer?
    Just some brain farts at 6am. Not my best part of the day.
     
  3. andrerodpt

    andrerodpt Member

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    When you add less demand to the dropping of the prices as seen since mid 2014, it's the perfect storm for them.
     
  4. jhm

    jhm Well-Known Member

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    The average natural depletion rate of oil wells is about 6% per year. Should demand fall faster than natural depletion that would be an impossible blow to the industry. But even if demand were only declining 2% pa, I think the oil industry would still try to compete for market share, fantasize about new demand somewhere in Asia and perpetuate an endless glut. They can't even rectify the current glut which is much more mild.
     
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  5. electracity

    electracity Banned

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    Semi tractors mostly pull other companies' trailers.

    Three of the five axles are on the semi. There is more potential for energy recovery on the front axles. Electric semis will probably be designed to pull today's standard trailers.
     
  6. oneday

    oneday Active Member

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    The infrastructure requirements of a battery swap station for the benefit really seems to bring diminishing returns to me. Double the battery packs, storage space, the expensive machines to load/unload/mount/unmount etc.

    if the semi has 500-800 miles of range and can then supercharge back to full range in 60-90 minutes, why do you even need a swap. Even then if the truck is only driving 500ish miles a day it doesn't even need to supercharge, it just needs a very large AC connection.

    Supercharging or swapping would really only be necessary if they are only providing the semi's with 200ish miles of range.
     
  7. schonelucht

    schonelucht Well-Known Member

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    Today Daimler Benz took the wraps off their fully electric semi. Key points : 26 tonnes gross capacity, 212kWh battery good for a 200km range, batteries on the truck, not the trailer and not swappable, cost of battery to be estimates 200EUR/kWh in 2025 (that seems very high) production ready 2020, CCS charging at 100kW.

    They are also moving forward with a light duty truck / delivery van. The Fuso Canter e-cell finished a first round of customer trials succesfully and the press release teases about more information next september. Their light duty truck has 48kWh packs also with CCS charging
     
  8. jhm

    jhm Well-Known Member

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    Congress Could Offer Huge Tax Incentives To Energy Storage | OilPrice.com

    A tax benefit for all energy storage is supportive of Tesla Energy broadly. But specifically Tesla Semi may benefit where it embraces battery swapping and fleet charging so as to balance the grid.

    The basic idea of battery swapping is to optimize the economic return on a fleet of grid connected batteries. In a typical day a fleet battery could go through about two cycles in transit and one cycle balancing the grid. Primarily the fleet charging of batteries is about making optimal use of solar and wind power, buying surplus power from the wholesale market, and supplying the local market when wholesale prices are at a peak. Essentially, a swap station is a peaking power plant. Bridging between two markets energy for trucking and the power market assures optimal economics and utilization.

    Without approaching fleet charging as a peak power system, one goes down the path of requiring utilities to build out peaking capacity to support trucking. We should not look at electric trucking in isolation from the supply of power. This is a huge opportunity for Tesla Energy to link solar generation, grid storage and microgrid power management.

    Does anyone think it makes sense to charge semi batteries with power stored grid batteries? This doubles the duty placed on batteries. What I am proposing is that semi batteries be charge directly from solar or wind power.
     
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  9. electracity

    electracity Banned

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    Not a semi. Musk was referencing a tractor, a over the road semi. The mercedes would be the cab/chassis for a large box truck (US terminology).
     
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  10. schonelucht

    schonelucht Well-Known Member

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    Thanks for the correction!
     
  11. dakh

    dakh Supporting Member

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    I think it's premature to speculate about this without knowing one key fact: are they designing a vehicle that won't have a driver cabin to begin with, or going for "driver for now until auto-driving is ready". Economics are fairly drastically different between the two.
     
  12. Fallenone

    Fallenone Active Member

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    Model X towing a payload with a combined weight of about 10k lb has less than 100 miles of range with a 90 kWh battery. Maximum weight for US semi is 80k lb. A simple linear extrapolation (which definitely won't be true) indicates you need 720 kWh battery to achieve 500 miles range. SC power is 145 kW. Even disregarding the marginal decrease of charging power, it will take 5 hours of current SC to fully charge back this imaginary 500 mile semi. Plus, these semis will be doing these long distance travel all the time and if they are using only one battery pack, degradation will be a serious problem
     
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  13. RichardL

    RichardL Member

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    I think this is a great idea as an interim solution - basically turns the combination unit into a hybrid
     
  14. oneday

    oneday Active Member

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    That's power from one SC stall designed for the model S/X/3's 85/90 kWh pack. The Semi could plug into multiple
    SC'ers, in locations designed for Tesla Semi's. The bigger the pack the faster you can safely charge. If you can get a half charge in a model S in 20 minutes, The same is possible for a semi, albeit just with proportionally more infrastructure.

    As to the Daimler semi, it looks like the gave the middle finger to designing an aerodynamic cab. At 26 tons gross and a 212kWh pack it has a range of 200km. This puts it at just over 1.7kWh per mile. So a full size Semi designed with aerodynamics in mind capable of 40 tons gross should be around 2kWh per mile. I think this is right in line with others estimates. A 1000kWh pack would give 500 miles of range. At 60mph it would take 8 hours 20 minutes to run out of range. Let's say the truck charges the remaining 15+ hours a day. At 80% charging efficiency the semi needs an 83kW connection. Sure this is big but lots of semi's drive at night, and most truck stops are in the middle of nowhere, land is cheap, so it's not hard to imagine multi mWh solar fields distributed throughout the country nearby truck stops.

    I don't think degradation is going to be as much of an issue people say it is. It certainly hasn't been on the S and chemistries are only improving. A semi will take 5 years + to reach a million miles, even if the battery has degraded 30% in that time the semi has paid for itself by then. Buy new packs, old packs get recycled to TE.
     
  15. Fallenone

    Fallenone Active Member

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    If we're talking about C in terms of charging, then to achieve the same C for Model S/X, the wire for semi would be very very big to accommodate all that A, otherwise it will just melt.

    Charging a truck 15+ a day seems a very very low efficiency of the truck itself to me. Regulation has 11 hour of driving for semi trucks. Also, having most of the time charging the electric semi totally defeats the purpose of developing it. The point was increase utilization and efficiency, not lowering it. If you need to charge 15+ hour a day. That basically lowers the efficiency of the truck by a factor of two. No one is going to use this type of transportation.

    Degradation on the S was not a problem because the batteries were not daily cycle, it takes more like a week to complete a cycle for each of the cell in the pack. This is also the reason the battery in the cars are different from those in the Powerwall, which is designed to run daily cycles. The semi situation is totally different from the S/X/3 because you want them to operate to maximum and you either need the daily cycle batteries, which is more expensive, or have some spare packs to rotate. Otherwise they will be abused.
     
  16. AZ Desert Driver

    AZ Desert Driver Rare combination

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    Remember that the production of oil and gas has uses beyond transportation fuels. Most of the plastics of the world - such as your computer keyboard - are petroleum based. Sure, fuel is a big chunk of Oil companies, but "only" about 30% of the product stream. I'm not convinced that his "impossible blow" will be fatal. Hurtful, yes...but not a bankruptcy, impossible blow.
     
  17. neroden

    neroden Model S Owner and Frustrated Tesla Fan

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    #37 neroden, Jul 27, 2016
    Last edited: Jul 27, 2016
    Land transportation fuel is about 2/3 of oil usage, though importantly it's the *most profitable* portion. This demand is going to go to near-zero within 15 years.


    In order to get a 6% overall decline, you only need a 9% decline in land transportation fuel demand. There are about 1.2 billion cars now. A very rough guess would claim that 108 million electric -- or plugin hybrid -- cars removes 9%. (Plugin hybrids are almost always powered by electricity, because electricity is typically cheaper, at least until oil drops below $20/bbl -- so for projecting oil demand they matter.)

    But this isn't right because some cars use a lot more fuel than others, and they're more likely to switch to electric first. Nobody cares if someone's "yard car" which is sitting in the yard, not driven, is gasoline-powered. Switching out the most heavily used, biggest fuel hogs has the biggest impact on oil demand. This makes it hard for me to tell how many cars per year are actually needed to make this big a dent in oil demand; it's obviously *less* than 108 million per year, a lot less, but I'm not sure how much less.

    In 2018, Tesla will only be putting out half a million cars a year. But I find from ev-sales.blogspot.com that the industry as a whole seems to be putting out 810K cars per year this year, 2016 (mostly in China). Chinese sales are doubling yearly (actually growing by a factor of 2.18) and I expect everyone else will catch up to that growth rate eventually. BYD has stated their intent to produce as many electric cars as Tesla as fast as Tesla... and they're only one of several successful Chinese electric car companies. This should give us over 3 million electric or plugin hybrid cars per year in 2020, over 18 million in 2022, and 100% of world sales in 2024. This actually seems fairly plausible. It won't be 100% of world sales due to dropoff at the end of the adoption curve, but it'll be close enough, with gas-only cars reduced to a niche; once purchase price parity is reached, there's just no advantage to cars without a plug, and only crazy people will buy them. Adoption rates might actually accelerate past this.

    I agree with you that the demand drop doesn't need to be as fast as 6% per year to smash the oil industry, because *they are still drilling new wells*! The 6% rate is dependent on them NOT doing that. Every well they drill reduces their profits, basically, but they'll keep doing it until *well* past the point where it was economic. The coal mining companies did this too.

    I am having trouble pinning down exactly when the death of the oil companies happens, since there are so many moving parts. I feel very safe in my projection that they'll all be bankrupt by 2030 -- there's lots of breathing room in that projection.

    I tried to figure out the oil price *after* the disappearance of land transportation from the oil market. Global demand is now around 96 million barrels per day, so it should be anywhere from 28 million to 36 million barrels per day depending on your estimate of non-transportation demand. The cheapest-cost producers will survive; the more expensive will shut their wells in. There are big arguments over what various countries' production costs are because they're secretive. There are some ultra-cheap Middle Eastern oil producers, including Saudi Arabia, Iran, Iraq, Kuwait, and the UAEs. Together they do not produce enough for this residual non-transportation demand. Add in some other relatively cheapsources like the older US oil wells (not the new ones) and the older Russian oil wells, and it's covered easily, even accounting for 6%/year depletion. These already-existing sources have production costs (for the wells which already exist) somewere between $15/bbl and $25/bbl. This is where the oil price is headed in the 2024 timeframe.

    The really important point for the multinational oil companies is that most of them are heavily invested in (a) much more expensive sources of oil, and (b) oversized refinery systems which (c) are focused on producing gasoline, or maybe diesel.

    The drop in sales will mean that the multinationals can't cover their debt service, and that means bankruptcy.

    Writing off the overpriced sources of oil will slash their book value and make it hard to borrow, exacerbating the problem.

    Cancelling the dividend will slash the stock value and make it hard to recapitalize by issuing stock; instead, they will likely load up on debt to pay the dividend (they are already borrowing money to pay their dividends) which vastly increases the chance of bankruptcy.

    Many of the refineries will become worthless due to overcapacity. Furthermore, restructuring the refineries to optimize them for a different primary product (not gasoline) is expensive.
     
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  18. oneday

    oneday Active Member

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    #38 oneday, Jul 28, 2016
    Last edited: Jul 28, 2016
    The wire wouldn't have to be bigger, it could be, but you could also just have multiple charge ports, each port with 145kw or whatever max per charge port, if you want to supercharge you just have to plug in x number of charge cables. or you could have some kind of single giant charge cord as well, that plugs in either autonomously or mechanically. No matter how its set up I'm sure they would want to be capable of supporting multiple charging options.

    As to 15 hrs of charging being a waste of time, I agree, I wasn't saying every truck should operate this way. Just like the MS being able to accept different amperages so should the semi, obviously. All I was saying whether you are supercharging or with an AC connection the semi can be capable of multiple amperages: charge in 90 minutes, charge in 15 hours, or charge over a weekend; all of this technology just crosses over from the MS.

    Now as to your degradation concerns, Tesla's Li-ion cells have really good cycle lifes. And there are many ways you can increase your battery life, ie. not fully draining or overcharging. This is why Tesla puts buffers on each end of the usable kwh in the MS. Using the data on the Powerwall, that particular Li-ion cell is capable of 5000 cycles before reaching the end of its useful life. Its useful life is considered to be over when the battery degrades to 80%. For total mile calculation lets assume we have linear degradation and we, on average, for the life of the battery we use 90% of our total pack. In the testing they do a 80% depth of discharge to calculate cycle life. Lets assume a 1000kWh pack delivers 500 miles of range. For total mile calculations(based on the above) we can only use 80% or 400 miles, and then we also only get 90% useful life out of this, so that reduces our total miles to 360 miles per charge, hypothetical. Multiply that times the 5000 cycle rating the semi battery has a useful life of 1,800,000 miles. Cycle life is NOT going to be an issue here. The weight of the pack is the main issue here, but all of the other efficiencies make the trade off worth it.

    I want to throw out a rough cost per mile calculation comparison here based on a few assumptions and see what people think.

    Diesel
    6.5 mpg @ $2.40 gal (Jul/2016 avg US price) = $0.37 per mile

    Electricity
    2kWh per mile & 80% efficiency = 2.5 kWh per mile @ $0.15 kWh (Solar City rooftop lease prices) = $0.37 per mile

    So we have cost parity, obviously these are rough numbers and don't include many things including the hidden cost of burning petroleum products (which are huge). However, from a strictly financial perspective all we need to do is, 1. bring the price per kWh down or, 2. use better numbers :)

    Edit: Fallenone: I now see that you mentioned that MS has different cell chemistry than Powerwall, so you are right that Tesla might not use the same chemistry as the MS.

    I tried to find cycle life of the MS battery but couldn't find it anywhere. I wonder what the cost to manufacture per kWh difference is between the MS chemistry and Powerwall chemistry.
     
  19. -=buzz=-

    -=buzz=- Member

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    I know Tesla is unlikely to go this route, but for semi trucks a hybrid solution could work too:

    Here are my thoughts:

    Drop a P90D drivetrain into a semi.
    - Dual Motors to allow torque sleep.
    - P to get into comparable HP regions
    - Regear for optimal Efficiency @ 65mph
    - Regear it for <90mph, to push torque higher, if it doesn't conflict with the efficiency target
    - If the current battery pack can't be put on the Floor like in MS/MX it should be possible to fit it within the load strucutre by folding in in half (like the electric MB Semi prototype)
    - Beef up cooling system for battery and Motors, to handle higher loads

    Replace the existing engine with a 150KW Generator.
    - Average power estimations range from ~100KW (according to a german study on a mixed urban-rural-Highway scenario, which I can't find right now) and 150KW for US Highways (according to a post in the Short-Term TSLA-Thread)
    - As an example a Volvo Penta Generator like this generates 150KW with a consumption of ~10 gal/h (and 100KW @ ~7 gal/h)

    With this you'd get an average 6.5MPG @ 65mph (or 7.1MPG @50mph for european trucks )
    Best case consumption of new ICE trucks in europe is ~7.8MPG (30l/100km) with average closer to 6.8MPG (35l/100km) for normal day-to-day Operation (mixed)

    Additionally we get the following benefits:
    - Regen capability (> 10% according to this graphic on this site)
    - option to drive electric only (low noise, zero emissions)
    - lower noise emissions due to fixed rpm
    - removal of transmission (900lbs) an driveshaft
    - replacing the massive engine (2400+lbs) with a lighter generator (~2100lbs for the penta including tank)
    - resize exhaust treatment due to lower gas flow and lower variation in operationg conditions (constant rpm)
    - Instead of "up to 45 %" engine efficiency for best case, the generator is running at a constant load (36% for 150KWh/10gal)
    - The volume saved by smaller and removed parts should allow more freedom for aerodynamic optimisations
    - Base drive load will be provided by the generator. The battery pack will see very low loads and cycles.

    Most of these should push Efficiency even higher without causing any additional cost.


    Once you have this system running you can start to optimize even further with different battery and generator sizes or additional motors
    I know this looks a lot like the "Nikola one"-truck but for me this looks to be the fastest way to get into the semi business without much higher costs.


    That's it for my fist post :)
     
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  20. bxr140

    bxr140 Active Member

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    Not worth it. Hybrids are stop gap solutions to evolving battery technology. It doesn't make sense to put nonrecurring time/money into a product that is going to have a relatively short lifecycle.

    It's smarter to put the effort into developing a full electric vehicle, even if the dev phase uses unprofitably heavy batteries. Then wait for battery technology to converge on the e-truck business case before moving to mass market, which wont be long after the dev phase once things like the gigafactory are operational. In the meantime, hone adjacent technology like autonomous features and especially charging solutions--since its obvious you can't just "ultra supercharge" a bunch of electric trucks with simple improvements to existing infrastructure.
     
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