11 ms·

Tesla Semi, a Deep Dive

181 points by oxplot 4y ago

oxplot 4y ago
- derefr 4y ago
  > Why the bloody fk would you say that about anything ever? Because there are fundamental limits in chemistry to how little mass an electrical capacitor electrolyte material can have per unit charge; and because there are fundamental limits in physics to the dynamics of self-propelling systems (upper-bounded in efficiency by the ideal rocket equation.) We know those things. Science can prove that we can't do certain things. Thermodynamics, y'know? Of course, we can work around having to do those specific things — e.g. in the case of cargo ships, we could use far more numerous, smaller, lower-mass ships, rather than a few ultra-massive ones; or more obviously (and to Gates' point) we can use some other form of energy storage than capacitance — but that doesn't mean that we're actually then doing those impossible things. Those specific things are still impossible.
  - fuckHNtho 4y ago
  - meindnoch 4y ago
    >there are fundamental limits in physics to the dynamics of self-propelling systems (upper-bounded in efficiency by the ideal rocket equation.) You realize a car works by pushing against the road, not by expelling propellant, right? The rocket equation is irrelevant here.
    - derefr 4y ago
      The ideal rocket equation isn't about the mechanism a thing uses to move; it's fundamentally a thermodynamic equation to describe how far you can get (inverse of a pork-chop plot) when you're fighting against a continuous decelerating force (gravity is one kind, but drag is another; there is no requirement that these forces be constant, decreasing-with-distance, or have any other particular curve), given 1. the energy you have available to accelerate with, and 2. how much mass you lose per watt expended. The convenient thing about the ideal rocket equation as an genericized mental model, is that (solid-propellant) rockets are themselves the ideal movers; "throwing stuff out the back" is the ideal/optimal way to accelerate something; rockets always use the most energy-dense propellants we know of; and thus rockets also spend the most mass per watt as they burn. This means that rockets (and the ideal rocket equation) provide an upper bound on achievable delta-V that no other propulsion mechanism can exceed. You can think of any other propulsion mechanism as a kind of worse rocket—something that is shifted forward on the the ideal rocket equation curve, and/or has a higher exponent for the curve, such that it "goes exponential" (becomes impractical) in fuel requirements sooner than a rocket would. The rocket equation is a useful and relevant model for understanding e.g. the amount of bunker fuel needed for a sailing of a trans-atlantic container ship, because 1. a container ship is overcoming continuous drag through the water, and 2. a container ship's fuel makes up a non-negligible percentage of its weight and therefore changes its drag; and 3. a container ship spends its fuel (becomes lighter / more fuel-efficient!) as it moves. The fuel requirements of a container ship can "go exponential" just like a rocket's can—though, given the energy-density of the fuel they currently use, other practical considerations (like decreased buoyancy from increased mass causing them to scrape the bottoms of shallow shipping channels) put limits on ship carrying capacity before the rocket equation does. With a less energy-dense energy-storage medium, e.g. batteries, this would not necessarily be true. Land vehicles are still governed by the ideal rocket equation — they move through the atmosphere just like anything else, and at any speed above ~10mph, they spend energy mostly to overcome drag rather than ground friction. (Remember, a tire is a flywheel!) There is a reason that a motorcycle can take you further than a car can on the same amount of gas, and that reason can best be modelled not by the fuel efficiency of the motor, but rather by the ideal rocket equation. Vehicles relying on batteries lose no mass as they move (with oxide formulations, they gain mass!), so they're always going to be worse than vehicles with liquid-fuel engines at overcoming drag. So they're going to be worse "ideal rockets", and "go exponential" in fuel requirements, at lower ideal-delta-V cutoffs than vehicles with liquid-fuel engines will.
newyankee 4y ago
Even if the payload is 30k-35k lbs in the conservative case, it still makes it a no brainer for high volume , relatively lower weight applications. Consistent, predictable routes and economies of scale can be achieved on high traffic routes, especially if the terrain is uneven. I just hope the Semi can outperform Diesel semi a lot in the lifetime maintenance costs.
- oxplot 4y ago
  In the presentation, Musk stated that the drivetrain is guaranteed for 1 million miles. I have no data on what sort of guarantees Diesel Semi manufacturers offer. Would be good to work that out. There is battery life and degradation as well to take into account.
  - daguava 4y ago
    Elon's word is worth very little these days, needs to be on paper under scrutiny of a lawyer or it's garbage.
    - DarmokJalad1701 4y ago
      Regardless of whether you believe Elon, this has been shown for the Model 3 drivetrain before https://electrek.co/2018/10/15/tesla-drive-after-million-miles-test/ https://electrek.co/2018/10/15/tesla-drive-after-million-mil... And it's not that hard to believe given that it is a system with very few moving parts and no constant explosions happening in it during operation.
      - josefx 4y ago
        > this has been shown for the Model 3 drivetrain Is there anything more than a picture released by Tesla to that article? I would have expected test results or at least some data on how it holds up.
      - daguava 4y ago
marsven_422 4y ago
justapassenger 4y ago
Calling it deep dive is questionable, at best. Tesla only released marketing fluff so far. No price, no payload capacity, no details of range (yeah, it did 500m drive, but how does it handle different speeds, environmental conditions, terrain profiles, etc), no details on the tech, etc. It has potential to be really cool, but at the same Tesla isn’t exactly known for their marketing fluff being accurate in the real life.
- brookst 4y ago
  Suggest you read the article. They do a pretty good job of estimating a lot of that and showing their work.
  - justapassenger 4y ago
    Yeah, exactly. Estimating, based on marketing fluff. Let’s wait for real numbers before we claim deep dive.
    - me_me_me 4y ago
      Bingo, if its a working real product. Why would then not released concrete numbers on the most important factors? Its like building a house, and only listing colours that house can be painted with and that it comes with reasonable amount of doors and windows. Buy now!
    - brookst 4y ago
      If you think Tesla's "marketing fluff" is factually wrong, you can make a killing with a lawsuit. Misleading investors is a huge thing. Fluff can lack details, but if it false then Tesla will be in a world of hurt. BTW can you explain how the height of Pacheco Pass on I-5 is marketing fluff?
- oxplot 4y ago
  - 4y ago
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greatgib 4y ago
So basically, if I'm right, you need a nuclear power plant for 500 to 1000 of these trucks if we assume one charge per day. That looks awfull to me, no?
- oxplot 4y ago
  Watch the delivery event. They address that.
  - oxplot 4y ago
    TL;DR they sell solar+battery backed Megachargers to go with the trucks.
- anonporridge 4y ago
  You can't drop a comment like this without sketching out your math and base assumptions. I would guess you're assuming a 1GW nuclear reactor, and each truck ~1MWh of battery. Wouldn't that be ~1000 trucks charged per hour, not per day? Are you off by 24x?
  - u8080 4y ago
    Why do we have traffic jams at busy hours?
- jnsaff2 4y ago
  So basically, the battery-powertrain efficiency is about 3-4 times better than with diesel. You need 3-4 nuclear plants worth of energy now. But lets see about your math as well. One reactor (of which there may be several in a plant) is lets say 1GW. The semi will charge at say 1MW. So 1000 of them can charge at the same time. It takes about 1 hour to charge the battery so we are already at 24000 charges per day. Each of them can cover ~800km so about 19 million fleet km or 480 trips around the earth or about 25 round trips to the moon.
- hoseja 4y ago
  I assume you don't mind pulling three times the nuclear powerplant's worth of dinosaur juice from earth?
bombcar 4y ago
Tesla Semi is not the only contender out there now (or at least in progress): https://freightliner.com/trucks/ecascadia/ https://freightliner.com/trucks/ecascadia/ https://www.peterbilt.com/electric-vehicles https://www.peterbilt.com/electric-vehicles https://www.macktrucks.com/trucks/lr-electric/ https://www.macktrucks.com/trucks/lr-electric/
- oxplot 4y ago
  Those "contenders" are referenced in the article: - Escadia has less than half the range of Tesla Semi and ~6 times slower charging rate per mile. - Peterbilt has 3.5x less range that Tesla Semi and ~10 times slower charging rate per mile. - Mack has 5x less range than Tesla Semi and ~10 times slower charging rate per mile (not in the article — I looked at the spec on the link). What are they exactly contending on?
  - suction 4y ago
  - Retric 4y ago
    You’re assuming that range is actually useful. There’s a reason Tesla is also producing a 300 mile semi, EV’s really only work for short haul trips anyway so a big battery is pointless for many users. Ideally you have charging infrastructure at a loading dock between shore trips not along the highway at which point a 250 mile Escadia vs a hypothetically faster charging 300 mile Tesla isn’t really worth much without a much larger investment in charging infrastructure.
    - oxplot 4y ago
      > You’re assuming that range is actually useful. I'm not assuming that. The entire trucking industry keeps talking about how they won't buy low range stuff. Also, while batteries are still slow to charge, any extra minute spent waiting to charge multiple times on a trip is money lost. EDIT: instead of speculating, get hold of someone in those companies that put order down for Tesla Semi and ask them why in their right mind they would do that. Then come back and enlighten us with their response.
kevingadd 4y ago
It's bizarre that they didn't rethink the seat placement in the cab. Every opinion I saw from truck drivers was that they didn't want a centered seat because it impairs visibility, but Tesla's going through with that? Why not put it on the left or right side like virtually every other car? I wonder if they did some studies to convince themselves that it's a good idea.
- deleted 4y ago
  [deleted]
- oxplot 4y ago
  > I wonder if they did some studies to convince themselves that it's a good idea. They explicitly call out the research they did in collaboration with the industry and the drivers that informed this decision. All in the presentation.
- bryanlarsen 4y ago
  Anybody who has driven agricultural tractors knows a center position is better.
  - josefresco 4y ago
    On farmland maybe, but US roads have lanes, and specific behaviors that will make this transition difficult for some. Thankfully I'm sure there's a new generation that will adapt better. The industry annual turn over rate is over 100% I believe.
    - bryanlarsen 4y ago
      Farmers do sometimes drive tractors on roads with lanes.
glitchc 4y ago
Wow, we can finally make a meaningful dent in emissions, not to mention pollution. In North America, the trucks are the primary mode of goods transportation, and they, not cars, contribute the bulk of transportation emissions.
- pengaru 4y ago
  > In North America, the trucks are the primary mode of goods transportation, and they, not cars, contribute the bulk of transportation emissions. ORLY, source? According to epa.gov [0] light-duty vehicles constitute 57% of transportation sector GHG emissions. Medium-and Heavy-duty trucks: 26% [0] https://www.epa.gov/greenvehicles/fast-facts-transportation-greenhouse-gas-emissions https://www.epa.gov/greenvehicles/fast-facts-transportation-...
  - akiselev 4y ago
    According to the DOE [1]: Light duty: < 10,000 lbs. Medium duty: 10,000-26,000 lbs. Heavy duty: > 26,000 lbs. Light duty covers most of the 10-20' UPS/Fedex/whatever trucks for last mile urban delivery which is far less efficient than delivery to a warehouse. Without more data on fuel consumption by gross weight, it's impossible to separate industrial delivery from personal travel/commuting. [1] https://afdc.energy.gov/data/10380 https://afdc.energy.gov/data/10380
    - pengaru 4y ago
      According to search results those delivery trucks are >10,000lbs GVW. Do you have any better sources backing your UPS/Fedex/Whatever light-duty claim than the random results I find in ddg searches?
      - akiselev 4y ago
        You're probably right because the max GVW on a single axle is 20,000 lbs but my source is the USDOT sticker on the license plates of several Fedex and UPS trucks that deliver to my suburban address and my parents' exurban address.
Invictus0 4y ago
Nit: It seems backwards to measure efficiency in terms of kwh/mile. One would expect a higher efficiency value to be better.
- oxplot 4y ago
  The best metric I can think of is expected lifetime miles driven over total cost of ownership. But I don't get why you think it's backwards! You want kwh/mile to be low. Basically, you want to use as little amount of energy stored in your battery to drive a mile. That's what that is.
- foobarbecue 4y ago
  I agree. The equivalent of mpg is miles per kWh. Using the reciprocal is confusing.
  - osigurdson 4y ago
    How about MPJ (Meters per Joule) since it is close to MPG - though the numbers would be tiny. Maybe km per GJ is more appropriate.
    - alkonaut 4y ago
      The distance-per-energy is numerically backwards compared to the energy-per-distance. This is important when e.g. wondering which car to replace, calculating a fleet average consumption and so on and so forth. For example: "Which saves more gasoline, going from 10 to 20 mpg, or going from 33 to 50 mpg"? There is good reason that the rest of the world uses the opposite system, and the reason isn't just that no one else uses gallons. It's that it's an objectively worse way of communicating fuel consumption in every single way that matters.
      - osigurdson 4y ago
        >> "Which saves more gasoline, going from 10 to 20 mpg, or going from 33 to 50 mpg" I'm surprised such questions come up often. Usually a current vehicle gets x MPG and a new one might get y. We use l/100 km in Canada. I think the primary advantage is it relatively easy to compute number of liters needed on a longer trip. It isn't super important however - better just to fill up! PS I was mostly kidding about using MPJ. The numbers would be tiny and hard to make sense of.
dchuk 4y ago
I work with very large fleets making and selling software to them. Basically none of them are operationally able to go from 15 minute diesel fill ups on any corner to the infrastructure and load planning EVs require. Like they literally don’t have the software or expertise to plan the loads around electric needs without losing money on every load. Trucking is a single digit percentage margin business. These trucks are more expensive, require infrastructure that doesn’t exist, charge slower, and don’t go anywhere near as far as diesel trucks. And no fleets in North America are ready to figure out converting a 2000 mile long haul over the road route into 5 400 mile EV relays. Short haul loads? Sure. In places that demand EV on certain timelines (like California). But for everything else, these vehicles require a fundamental reshaping of transportation in America. Not saying that’s not possible, but it ain’t happening any time soon.
- sdze 4y ago
  Geo-Arbitraging Fuel is also not easily attainable. Like they do here in Europe, where you can fill up your >1400-Liter-Diesel tanks with cheaper eastern Europe Diesel and bypass all the expensive Western Europe Fuel that drives you 5000KM.
- kolbe 4y ago
  I can't take you seriously if you only cite the negatives and not the positives. There's $60k/year of fuel savings to be had here. Show why that isn't enough, rather than ignoring it.
- Joeri 4y ago
  Europe has mandatory rest stops of at least 45 minutes, so any software with the ability to plan around those should have the ability to convert them easily to recharge stops. That doesn’t mean the recharge infrastructure exists overnight, but those same stops are being converted to support the rollouts of electric car fleets (e.g. belgium is going to mandate corporate car fleets convert to electric from 2026).
  - adamors 4y ago
    > Europe has mandatory rest stops of at least 45 minutes I'm not a trucker, but if your source is https://transport.ec.europa.eu/transport-modes/road/social-provisions/driving-time-and-rest-periods_en https://transport.ec.europa.eu/transport-modes/road/social-p... I don't read it as mandatory, more like a recommendation.
Animats 4y ago
Still no answer to the big question: how big and heavy is the battery? This thing has to have a huge battery. That cuts into the payload.
- mlindner 4y ago
  The fan community already has that figured out from the standard margin of EVs at "0" miles of range, combined with the percentage state of charge drop from going 500 miles, and the stated efficiency in the presentation (under 2 KWH/mile) and by Elon on twitter (1.7 KWH/mile). This makes it pretty certain that the battery is 1000 KWHr.
  - F_r_k 4y ago
    kWh
  - sofixa 4y ago
    Which is double the size of the other trucks to which it was compared to in the article. So either they're making a massive tradeoff or have managed a physics breakthrough (battery weight or density).
    - codeulike 4y ago
      Efficiency is key, as with cars
    - rep_movsd 4y ago
      Typical "We can do 2x,10x better than others" Musk advertising
    - Animats 4y ago
      That's about 15,000 pounds of battery, correct?
      - vardump 4y ago
        No one knows exactly, but I'd guess closer to about 10000 pounds. Semi's battery is not going to need as much armor.
enqk 4y ago
Why don’t we just put overhead electric lines on highways for semis to pull electricity from, rather than lose weight on big batteries?
- oxplot 4y ago
  While it is theoretically possible to use overhead electric lines to power vehicles on highways, there are a few challenges that would need to be overcome in order to make this a practical solution. For one, the infrastructure required to support such a system would be quite extensive, and would likely be expensive to install and maintain. Furthermore, the system would only be able to provide power to vehicles while they are on the highway, so they would still need some form of on-board power source for use when they are off the road. Overall, while this idea has some potential, there are currently more practical and cost-effective solutions for reducing the weight of vehicles, such as the use of lightweight materials and more efficient batteries.
  - trekkie1024 4y ago
    Feels like the above comment was written using ChatGPT :)
    - deleted 4y ago
      [deleted]
    - deleted 4y ago
      [deleted]
  - panick21_ 4y ago
    Lightweight materials doesn't change physics. In railroading we have long ago learned that long terms power delivery via overhead lines is by far the cheapest and best solution.
    - oxplot 4y ago
      I agree - trains make more sense than running overhead wires over highways.
digestives 4y ago
Engineering Explained made a good breakdown and analysis video on the physics of the truck: "Does The Tesla Semi Make Any Sense?" https://www.youtube.com/watch?v=Uv44W7xa4IU https://www.youtube.com/watch?v=Uv44W7xa4IU
- yourapostasy 4y ago
  The TL;DR of that great video goes against Betteridge's Law: yes it makes sense ("no fatal flaw found"), with the known information at the time Jason made the video. The charging infrastructure is likely not trivial, though; in the comments it was pointed out the infrastructure likely makes heavy use of batteries to avoid stressing out local substations and avoid abusing grid peaking.
  - oxplot 4y ago
    > the infrastructure likely makes heavy use of batteries to avoid stressing out local substations and avoid abusing grid peaking From Tesla's presentation, it looks like that.
    - yourapostasy 4y ago
      Right, and that throws off calculations I've seen so far on Semi's ROI because I haven't been able to find out what that charging infrastructure costs per truck in a single truck scenario, two truck scenario, five truck scenario, and so on. MWh of batteries and the accompanying high-voltage installs do not come cheap, and there is maintenance and capex replacements associated with all that. As much as all that costs and as much electricity it gulps down, you might as well arrange with the utility providers to put in the marginal additional equipment to secure a discount for always consuming out of nuclear or similar baseload during low utilization periods, and only rarely charging batteries outside those periods, trying as much as possible to avoid tapping peaking plants' output. The lifetime TCO calculations for the charging infrastructure for full battery replacement included is going to be interesting to peek into. On a simplistic basis, that TCO plus the electricity costs would be put up against the cost of diesel, Diesel Exhaust Fluid (DEF), Diesel Oxidation Catalyst (DOC) catalytic converter, maintenance on the DEF and DOC subsystems, and so on. With my investor hat on, I still don't have the numbers I'd like to see to evaluate whether the truck is a slam-dunk ROI on short-haul routes.
abledon 4y ago
I can't wait till Munro and co take a look into this stuff. The amount of people already crapping on this is astounding.
- oxplot 4y ago
  Those whose opinion actually matter have done the math and put orders in to save them cost in the long run. Of course, if right now, the load capacity or the range isn't applicable to one's business requirements, then Tesla Semi doesn't make sense. However, cost is often the biggest driver in any business. If a business can change things around to fit within the current constraints of the Semi, then they can do a cost-benefit analysis and Tesla Semi may then make economical sense.
  - oseityphelysiol 4y ago
    I expect the current orders to be PR motivated.
    - oxplot 4y ago
      Hard to tell, but given Tesla's historic record, demand for their products has only ever increased (discounting the current China situation which most likely has nothing to do with disparity between PR and actual product perf).
      - oblio 4y ago
        What's the "China situation"?
  - SpelingBeeChamp 4y ago
    Pepsi’s order was placed in 2017.
    - oxplot 4y ago
      Not sure what you're implying with this. Specs have remained exactly the same and now, they've actually delivered on the spec they advertised in 2017.
afiori 4y ago
Some time ago I heard that the major obstacle to this truck is the weight. That is trucks in the US have a strict max tonnage and so the Tesla Semi can only be used to transport lightweight or not full cargo
- sschueller 4y ago
  Similar in the EU and Canada where the limit is 40 metric tons (88,000 lbs) vs the US where it is 80,000 lbs.
theluketowers 4y ago
I've been fascinated watching the progress of Edison Motors (https://www.edisonmotors.ca/ https://www.edisonmotors.ca/), who are making a diesel electric hybrid semi. Their logic and arguments make a lot of sense: the diesel engine gets to run at its peak RPM 100% of the time to charge the batteries - and it gets to take advantage of the perks of electric like regenerative breaking, quieter operation, and immediate torque. Not to mention the easier transition time when it comes to working within existing infrastructure. There's also all sorts of side benefits with what they're doing like the semi itself being a generator on wheels for heavy duty equipment. Lots of fascinating stuff coming from them, and they already have a driving prototype :)
- oxplot 4y ago
  The problem with hybrid vehicles in general is that they still rely on fossil fuels to some extent, so they're not a truly sustainable solution. And they have all the maintenance and reliability baggage of their fully ICE counterparts, something BEVs do away with. The time and money being spent on developing hybrid technology could be better spent on making fully electric vehicles more affordable and accessible. EDIT: and keep in mind, trucks are purchased with a long service life in mind (decades)
  - theluketowers 4y ago
    While not perfect, they do meet real world needs in ways that are better than current ICE options. A fully electric truck isn't really a viable option in the market they're building for right now (heavy duty working trucks for logging, etc). Additionally, getting a working hybrid option out into the wild still benefits the eventual transition to fully EV trucks as it allows for testing and validating of the electrical systems required to make a functional workhorse that can deliver value to its owners / operators as well as pushes forward the viability & benefit of electric vehicles in the eyes of the public / industry.
  - unethical_ban 4y ago
    They are a transition, to be sure, but especially for consumers who do 80% short trip and need the ability to do long trip, it would seem to ideal choice for the 2020s.
BatteryMountain 4y ago
Just use trains for bulk like a normal country.
- oxplot 4y ago
  It's all about economics. Whatever's cheaper wins. To that end, Tesla has mentioned in their presentations that a Tesla Semi convoy of only 3 trucks can be cheaper than a train for the same load.
  - panick21_ 4y ago
    The problem is that highways are literally not cheaper but massively subsidized and heavy trucks are destroying that public infrastructure because they are so heavy. So just saying its all economics when the underlying rules of the game are totally unequal is not that useful.
    - oxplot 4y ago
      Sorry I should have been more specific. I'm referring to economics from the viewpoint of the business operating a fleet. Given almost all business do not hold back from whatever incentive and subsidies are available to them, it's fairly reasonable boundary to confine the comparison to.
      - panick21_ 4y ago
        Its a reasonable boundary but not reasonable when discussing the politics and what as a society should be done.
  - me_me_me 4y ago
    > To that end, Tesla has mentioned in their presentations that a Tesla Semi convoy of only 3 trucks can be cheaper than a train for the same load. I can carry it on my magic carpet for even cheaper, trust me I am rich so I wouldn't lie... this time. Trains have replaceable engines, power-lines - no battery. Trucks will not be cheaper option no matter what mumbo jumbo techno jargon you throw at it. And decades of technological optimizations. And they dont need lithium to be made and maintained.
reillyse 4y ago
I always assumed the future of electric trucking would involve little battery trailers that could be quickly swapped out on a rolling basis by fleets of trucks. It seems the “refuel” paradigm makes sense for fuels where the majority of the fuel is consumed but maybe not as much for charging. With a network of truckers in the US a floating number of charging centers with batteries wouldn’t be that tough to create/maintain
- Lutzb 4y ago
  I worked for a company that builds electric trucks and that have also shown battery trailers with cargo space. The engineers told me that the coupling of the battery on the trailer with the semi caused them a lot of worries. High voltage/amperage combined with mechanical stress and failure scenarios (failing mechanical coupling of the trailer, destroying the battery connection). However it seems like the European companies heading this way.
- _ph_ 4y ago
  Yes, just exchanging batteries is an alternative to recharging. But it requires additional logistics and also the investment into additional batteries. There are of course scenarios, where battery change is the only practical way. Like it was with horse changes on long distance travel long ago. This changes quickly, if you have batteries with enough range to make recharging feasible. With electric cars the industry was quickly at the point and looking at the specs of the Tesla Semi, heavy trucks are basically there too. Which probably will kill any attempt at setting up a network for battery exchange before it was made.
- oxplot 4y ago
  > I always assumed the future of electric trucking would involve little battery trailers that could be quickly swapped out on a rolling basis by fleets of trucks. Maybe the future, but right now, I suspect the battery energy density is not forgiving enough for the battery to just be a carry load. Increasingly, the battery module is part of the structure of the vehicle and further works as weight to increase traction close to the drivetrain. There is also a lot of nitty-gritty details to do with safety, efficiency and cooling that makes moving the battery away from the Semi itself not a viable option ATM. Also keep in mind that at least for consumer cars, Tesla did try battery swap stations but nobody seemed to show any interest so they canned it.
codesnik 4y ago
I wonder if anyone considered trucking a swappable battery as well. That's not for semi, of course, but road trains do exist?
juurikas 4y ago
Hey all! I'm Jaan, the OP of the Semi article here. Great discussion already! I'm off the 'net for a few days but if you have questions or suggestions, hit me up on Twitter (@theEVuniverse) or on my email jaan/at/evuniverse.io. I also write a weekly EV industry newsletter which is where I uploaded this from. Cheers!
davidy123 4y ago
Disappointing there is not a word about safety to the outside world. I get they have to market to drivers, calling it a "beast," but large trucks are a great danger in terms of losing tires and, especially in cities, collisions. I see it is built with a scoop design so "things" (people, bikes, etc) hopefully don't get pulled under it so easily, but hopefully it also has advanced collision and awareness features suited to such a large vehicle. It is unfortunately typical of Musk to market to the aggressive impulse, rather than harmonious, even if his ultimate goals are beneficial.
- thehappypm 4y ago
  One of the biggest dangers of trucks is losing their brakes and going out of control. As the article points out, regenerative braking vastly reduces that problem. So that’s a safety win!
torginus 4y ago
Considering everyone tends to point out the Achilles heel of EV trucks is the high kerb weight limiting the tonnage of useful cargo, I find it really funny that their premier touted customer is Frito-Lay, whose products are universally referred to as bags of air.
- oxplot 4y ago
  Did a quick search. Diesel Semis' curb weight ranges b/w 10000lbs-25000lbs. The 10000lbs one may not be comparable in performance/range to Tesla Semi so keep that in mind. Tesla Semi based on the estimate in the article, is about 27000lbs.
- caf 4y ago
  Though their other launch customer is Pepsi whose products are cans of water.
  - pwpw 4y ago
    Just to point out the obvious, Pepsi and Frito-Lay are owned by the same company, PepsiCo.
mukundmr 4y ago
I don't understand why you don't have companies like Tesla building fuel cell (hydrogen) solutions for commercial use cases. Here is an article that explains it - https://www.bmw.com/en/innovation/how-hydrogen-fuel-cell-cars-work.html https://www.bmw.com/en/innovation/how-hydrogen-fuel-cell-car... If Tesla can build a super charger network, they can build a hydrogen refilling network.
- drexlspivey 4y ago
  Here’s a video explaining the pitfalls with hydrogen as a fuel https://youtu.be/f7MzFfuNOtY https://youtu.be/f7MzFfuNOtY
- sidcool 4y ago
  From Elon's previous comments, Hydrogen is fundamentally not scalable and uneconomical.
  - qubex 4y ago
    Setting aside Musk’s current plunge in credibility, his argument regarding hydrogen is predicated upon electrolysis. A vast network of transparent tubes and sunlight reflectors feeding genetically engineered microorganisms that release hydrogen would undermine that assumption, but transportation, storage, and energy density would indeed remain a problem.
- jackmott42 4y ago
  A charging network just requires some wire and electronics, everything is well understood and easy to do for experts in that field. Hydrogen on the other hand, is difficult to keep contained and cold enough to remain in liquid form. Even NASA who has worked with it for 50 years with massive budget and engineering expertise constantly has problems with it. For instance one of BMWs hydrogen cars you are not allowed to park in a garage! As hydrogen is expected to leak from it. And current hydrogen gas stations still suffer from this challenge. So hydrogen fuel cells do offer the advantage of better energy density for more range, but you have the dual difficulties of 1. how do I make the hydrogen efficiently AND cleanly and then 2. the infrastructure build out is actually as hard ad EV doubter think wires are.
bryanlarsen 4y ago
I wonder what kind of chargers Pepsico has installed. Sure, the ability to charge at 1MW+ is useful, but you won't want to use that often unless you want to spend all of your fuel cost savings replacing batteries. Just like a car, the battery will last a lot longer if you slow charge. But a slow charge on a 900kW battery is still a lot faster than you can get out of standard 240VAC. Pepsico probably wants to do 50-100kW overnight charging on their vehicles. I wonder if it's something like 1MW of power split between 8 stalls. So if one truck comes in during the day time, it can get a top up at 1MW, but overnight when there are 8 trucks parked, they all charge at 125kW or less.
- zaptrem 4y ago
  Charging a battery of this scale at 1MW likely won't have any more significant effect on life span than charging a Model whatever at a normal supercharger (which is negligible assuming thanks to battery temperature management and charge speed tapering).
  - bryanlarsen 4y ago
    If you always charge at a Supercharger you will have a reduced battery life.
ksec 4y ago
The Link is dead? What happened?

181 points by oxplot 4y ago

derefr 4y ago
> Why the bloody fk would you say that about anything ever? Because there are fundamental limits in chemistry to how little mass an electrical capacitor electrolyte material can have per unit charge; and because there are fundamental limits in physics to the dynamics of self-propelling systems (upper-bounded in efficiency by the ideal rocket equation.) We know those things. Science can prove that we can't do certain things. Thermodynamics, y'know? Of course, we can work around having to do those specific things — e.g. in the case of cargo ships, we could use far more numerous, smaller, lower-mass ships, rather than a few ultra-massive ones; or more obviously (and to Gates' point) we can use some other form of energy storage than capacitance — but that doesn't mean that we're actually then doing those impossible things. Those specific things are still impossible.
- fuckHNtho 4y ago
- meindnoch 4y ago
  >there are fundamental limits in physics to the dynamics of self-propelling systems (upper-bounded in efficiency by the ideal rocket equation.) You realize a car works by pushing against the road, not by expelling propellant, right? The rocket equation is irrelevant here.
  - derefr 4y ago
    The ideal rocket equation isn't about the mechanism a thing uses to move; it's fundamentally a thermodynamic equation to describe how far you can get (inverse of a pork-chop plot) when you're fighting against a continuous decelerating force (gravity is one kind, but drag is another; there is no requirement that these forces be constant, decreasing-with-distance, or have any other particular curve), given 1. the energy you have available to accelerate with, and 2. how much mass you lose per watt expended. The convenient thing about the ideal rocket equation as an genericized mental model, is that (solid-propellant) rockets are themselves the ideal movers; "throwing stuff out the back" is the ideal/optimal way to accelerate something; rockets always use the most energy-dense propellants we know of; and thus rockets also spend the most mass per watt as they burn. This means that rockets (and the ideal rocket equation) provide an upper bound on achievable delta-V that no other propulsion mechanism can exceed. You can think of any other propulsion mechanism as a kind of worse rocket—something that is shifted forward on the the ideal rocket equation curve, and/or has a higher exponent for the curve, such that it "goes exponential" (becomes impractical) in fuel requirements sooner than a rocket would. The rocket equation is a useful and relevant model for understanding e.g. the amount of bunker fuel needed for a sailing of a trans-atlantic container ship, because 1. a container ship is overcoming continuous drag through the water, and 2. a container ship's fuel makes up a non-negligible percentage of its weight and therefore changes its drag; and 3. a container ship spends its fuel (becomes lighter / more fuel-efficient!) as it moves. The fuel requirements of a container ship can "go exponential" just like a rocket's can—though, given the energy-density of the fuel they currently use, other practical considerations (like decreased buoyancy from increased mass causing them to scrape the bottoms of shallow shipping channels) put limits on ship carrying capacity before the rocket equation does. With a less energy-dense energy-storage medium, e.g. batteries, this would not necessarily be true. Land vehicles are still governed by the ideal rocket equation — they move through the atmosphere just like anything else, and at any speed above ~10mph, they spend energy mostly to overcome drag rather than ground friction. (Remember, a tire is a flywheel!) There is a reason that a motorcycle can take you further than a car can on the same amount of gas, and that reason can best be modelled not by the fuel efficiency of the motor, but rather by the ideal rocket equation. Vehicles relying on batteries lose no mass as they move (with oxide formulations, they gain mass!), so they're always going to be worse than vehicles with liquid-fuel engines at overcoming drag. So they're going to be worse "ideal rockets", and "go exponential" in fuel requirements, at lower ideal-delta-V cutoffs than vehicles with liquid-fuel engines will.

Even if the payload is 30k-35k lbs in the conservative case, it still makes it a no brainer for high volume , relatively lower weight applications. Consistent, predictable routes and economies of scale can be achieved on high traffic routes, especially if the terrain is uneven. I just hope the Semi can outperform Diesel semi a lot in the lifetime maintenance costs.

oxplot 4y ago
In the presentation, Musk stated that the drivetrain is guaranteed for 1 million miles. I have no data on what sort of guarantees Diesel Semi manufacturers offer. Would be good to work that out. There is battery life and degradation as well to take into account.
- daguava 4y ago
  Elon's word is worth very little these days, needs to be on paper under scrutiny of a lawyer or it's garbage.
  - DarmokJalad1701 4y ago
    Regardless of whether you believe Elon, this has been shown for the Model 3 drivetrain before https://electrek.co/2018/10/15/tesla-drive-after-million-miles-test/ https://electrek.co/2018/10/15/tesla-drive-after-million-mil... And it's not that hard to believe given that it is a system with very few moving parts and no constant explosions happening in it during operation.
    - josefx 4y ago
      > this has been shown for the Model 3 drivetrain Is there anything more than a picture released by Tesla to that article? I would have expected test results or at least some data on how it holds up.
    - daguava 4y ago

marsven_422 4y ago

justapassenger 4y ago

Calling it deep dive is questionable, at best. Tesla only released marketing fluff so far. No price, no payload capacity, no details of range (yeah, it did 500m drive, but how does it handle different speeds, environmental conditions, terrain profiles, etc), no details on the tech, etc. It has potential to be really cool, but at the same Tesla isn’t exactly known for their marketing fluff being accurate in the real life.

brookst 4y ago
Suggest you read the article. They do a pretty good job of estimating a lot of that and showing their work.
- justapassenger 4y ago
  Yeah, exactly. Estimating, based on marketing fluff. Let’s wait for real numbers before we claim deep dive.
  - me_me_me 4y ago
    Bingo, if its a working real product. Why would then not released concrete numbers on the most important factors? Its like building a house, and only listing colours that house can be painted with and that it comes with reasonable amount of doors and windows. Buy now!
  - brookst 4y ago
    If you think Tesla's "marketing fluff" is factually wrong, you can make a killing with a lawsuit. Misleading investors is a huge thing. Fluff can lack details, but if it false then Tesla will be in a world of hurt. BTW can you explain how the height of Pacheco Pass on I-5 is marketing fluff?
oxplot 4y ago
- 4y ago

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greatgib 4y ago

So basically, if I'm right, you need a nuclear power plant for 500 to 1000 of these trucks if we assume one charge per day. That looks awfull to me, no?

oxplot 4y ago
Watch the delivery event. They address that.
- oxplot 4y ago
  TL;DR they sell solar+battery backed Megachargers to go with the trucks.
anonporridge 4y ago
You can't drop a comment like this without sketching out your math and base assumptions. I would guess you're assuming a 1GW nuclear reactor, and each truck ~1MWh of battery. Wouldn't that be ~1000 trucks charged per hour, not per day? Are you off by 24x?
- u8080 4y ago
  Why do we have traffic jams at busy hours?
jnsaff2 4y ago
So basically, the battery-powertrain efficiency is about 3-4 times better than with diesel. You need 3-4 nuclear plants worth of energy now. But lets see about your math as well. One reactor (of which there may be several in a plant) is lets say 1GW. The semi will charge at say 1MW. So 1000 of them can charge at the same time. It takes about 1 hour to charge the battery so we are already at 24000 charges per day. Each of them can cover ~800km so about 19 million fleet km or 480 trips around the earth or about 25 round trips to the moon.
hoseja 4y ago
I assume you don't mind pulling three times the nuclear powerplant's worth of dinosaur juice from earth?

bombcar 4y ago

Tesla Semi is not the only contender out there now (or at least in progress): https://freightliner.com/trucks/ecascadia/ https://freightliner.com/trucks/ecascadia/ https://www.peterbilt.com/electric-vehicles https://www.peterbilt.com/electric-vehicles https://www.macktrucks.com/trucks/lr-electric/ https://www.macktrucks.com/trucks/lr-electric/

oxplot 4y ago
Those "contenders" are referenced in the article: - Escadia has less than half the range of Tesla Semi and ~6 times slower charging rate per mile. - Peterbilt has 3.5x less range that Tesla Semi and ~10 times slower charging rate per mile. - Mack has 5x less range than Tesla Semi and ~10 times slower charging rate per mile (not in the article — I looked at the spec on the link). What are they exactly contending on?
- suction 4y ago
- Retric 4y ago
  You’re assuming that range is actually useful. There’s a reason Tesla is also producing a 300 mile semi, EV’s really only work for short haul trips anyway so a big battery is pointless for many users. Ideally you have charging infrastructure at a loading dock between shore trips not along the highway at which point a 250 mile Escadia vs a hypothetically faster charging 300 mile Tesla isn’t really worth much without a much larger investment in charging infrastructure.
  - oxplot 4y ago
    > You’re assuming that range is actually useful. I'm not assuming that. The entire trucking industry keeps talking about how they won't buy low range stuff. Also, while batteries are still slow to charge, any extra minute spent waiting to charge multiple times on a trip is money lost. EDIT: instead of speculating, get hold of someone in those companies that put order down for Tesla Semi and ask them why in their right mind they would do that. Then come back and enlighten us with their response.

kevingadd 4y ago

It's bizarre that they didn't rethink the seat placement in the cab. Every opinion I saw from truck drivers was that they didn't want a centered seat because it impairs visibility, but Tesla's going through with that? Why not put it on the left or right side like virtually every other car? I wonder if they did some studies to convince themselves that it's a good idea.

deleted 4y ago
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oxplot 4y ago
> I wonder if they did some studies to convince themselves that it's a good idea. They explicitly call out the research they did in collaboration with the industry and the drivers that informed this decision. All in the presentation.
bryanlarsen 4y ago
Anybody who has driven agricultural tractors knows a center position is better.
- josefresco 4y ago
  On farmland maybe, but US roads have lanes, and specific behaviors that will make this transition difficult for some. Thankfully I'm sure there's a new generation that will adapt better. The industry annual turn over rate is over 100% I believe.
  - bryanlarsen 4y ago
    Farmers do sometimes drive tractors on roads with lanes.

glitchc 4y ago

Wow, we can finally make a meaningful dent in emissions, not to mention pollution. In North America, the trucks are the primary mode of goods transportation, and they, not cars, contribute the bulk of transportation emissions.

pengaru 4y ago
> In North America, the trucks are the primary mode of goods transportation, and they, not cars, contribute the bulk of transportation emissions. ORLY, source? According to epa.gov [0] light-duty vehicles constitute 57% of transportation sector GHG emissions. Medium-and Heavy-duty trucks: 26% [0] https://www.epa.gov/greenvehicles/fast-facts-transportation-greenhouse-gas-emissions https://www.epa.gov/greenvehicles/fast-facts-transportation-...
- akiselev 4y ago
  According to the DOE [1]: Light duty: < 10,000 lbs. Medium duty: 10,000-26,000 lbs. Heavy duty: > 26,000 lbs. Light duty covers most of the 10-20' UPS/Fedex/whatever trucks for last mile urban delivery which is far less efficient than delivery to a warehouse. Without more data on fuel consumption by gross weight, it's impossible to separate industrial delivery from personal travel/commuting. [1] https://afdc.energy.gov/data/10380 https://afdc.energy.gov/data/10380
  - pengaru 4y ago
    According to search results those delivery trucks are >10,000lbs GVW. Do you have any better sources backing your UPS/Fedex/Whatever light-duty claim than the random results I find in ddg searches?
    - akiselev 4y ago
      You're probably right because the max GVW on a single axle is 20,000 lbs but my source is the USDOT sticker on the license plates of several Fedex and UPS trucks that deliver to my suburban address and my parents' exurban address.

Invictus0 4y ago

Nit: It seems backwards to measure efficiency in terms of kwh/mile. One would expect a higher efficiency value to be better.

oxplot 4y ago
The best metric I can think of is expected lifetime miles driven over total cost of ownership. But I don't get why you think it's backwards! You want kwh/mile to be low. Basically, you want to use as little amount of energy stored in your battery to drive a mile. That's what that is.
foobarbecue 4y ago
I agree. The equivalent of mpg is miles per kWh. Using the reciprocal is confusing.
- osigurdson 4y ago
  How about MPJ (Meters per Joule) since it is close to MPG - though the numbers would be tiny. Maybe km per GJ is more appropriate.
  - alkonaut 4y ago
    The distance-per-energy is numerically backwards compared to the energy-per-distance. This is important when e.g. wondering which car to replace, calculating a fleet average consumption and so on and so forth. For example: "Which saves more gasoline, going from 10 to 20 mpg, or going from 33 to 50 mpg"? There is good reason that the rest of the world uses the opposite system, and the reason isn't just that no one else uses gallons. It's that it's an objectively worse way of communicating fuel consumption in every single way that matters.
    - osigurdson 4y ago
      >> "Which saves more gasoline, going from 10 to 20 mpg, or going from 33 to 50 mpg" I'm surprised such questions come up often. Usually a current vehicle gets x MPG and a new one might get y. We use l/100 km in Canada. I think the primary advantage is it relatively easy to compute number of liters needed on a longer trip. It isn't super important however - better just to fill up! PS I was mostly kidding about using MPJ. The numbers would be tiny and hard to make sense of.

dchuk 4y ago

I work with very large fleets making and selling software to them. Basically none of them are operationally able to go from 15 minute diesel fill ups on any corner to the infrastructure and load planning EVs require. Like they literally don’t have the software or expertise to plan the loads around electric needs without losing money on every load. Trucking is a single digit percentage margin business. These trucks are more expensive, require infrastructure that doesn’t exist, charge slower, and don’t go anywhere near as far as diesel trucks. And no fleets in North America are ready to figure out converting a 2000 mile long haul over the road route into 5 400 mile EV relays. Short haul loads? Sure. In places that demand EV on certain timelines (like California). But for everything else, these vehicles require a fundamental reshaping of transportation in America. Not saying that’s not possible, but it ain’t happening any time soon.

sdze 4y ago
Geo-Arbitraging Fuel is also not easily attainable. Like they do here in Europe, where you can fill up your >1400-Liter-Diesel tanks with cheaper eastern Europe Diesel and bypass all the expensive Western Europe Fuel that drives you 5000KM.
kolbe 4y ago
I can't take you seriously if you only cite the negatives and not the positives. There's $60k/year of fuel savings to be had here. Show why that isn't enough, rather than ignoring it.
Joeri 4y ago
Europe has mandatory rest stops of at least 45 minutes, so any software with the ability to plan around those should have the ability to convert them easily to recharge stops. That doesn’t mean the recharge infrastructure exists overnight, but those same stops are being converted to support the rollouts of electric car fleets (e.g. belgium is going to mandate corporate car fleets convert to electric from 2026).
- adamors 4y ago
  > Europe has mandatory rest stops of at least 45 minutes I'm not a trucker, but if your source is https://transport.ec.europa.eu/transport-modes/road/social-provisions/driving-time-and-rest-periods_en https://transport.ec.europa.eu/transport-modes/road/social-p... I don't read it as mandatory, more like a recommendation.

Animats 4y ago

Still no answer to the big question: how big and heavy is the battery? This thing has to have a huge battery. That cuts into the payload.

mlindner 4y ago
The fan community already has that figured out from the standard margin of EVs at "0" miles of range, combined with the percentage state of charge drop from going 500 miles, and the stated efficiency in the presentation (under 2 KWH/mile) and by Elon on twitter (1.7 KWH/mile). This makes it pretty certain that the battery is 1000 KWHr.
- F_r_k 4y ago
  kWh
- sofixa 4y ago
  Which is double the size of the other trucks to which it was compared to in the article. So either they're making a massive tradeoff or have managed a physics breakthrough (battery weight or density).
  - codeulike 4y ago
    Efficiency is key, as with cars
  - rep_movsd 4y ago
    Typical "We can do 2x,10x better than others" Musk advertising
  - Animats 4y ago
    That's about 15,000 pounds of battery, correct?
    - vardump 4y ago
      No one knows exactly, but I'd guess closer to about 10000 pounds. Semi's battery is not going to need as much armor.

enqk 4y ago

Why don’t we just put overhead electric lines on highways for semis to pull electricity from, rather than lose weight on big batteries?

oxplot 4y ago
While it is theoretically possible to use overhead electric lines to power vehicles on highways, there are a few challenges that would need to be overcome in order to make this a practical solution. For one, the infrastructure required to support such a system would be quite extensive, and would likely be expensive to install and maintain. Furthermore, the system would only be able to provide power to vehicles while they are on the highway, so they would still need some form of on-board power source for use when they are off the road. Overall, while this idea has some potential, there are currently more practical and cost-effective solutions for reducing the weight of vehicles, such as the use of lightweight materials and more efficient batteries.
- trekkie1024 4y ago
  Feels like the above comment was written using ChatGPT :)
  - deleted 4y ago
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  - deleted 4y ago
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- panick21_ 4y ago
  Lightweight materials doesn't change physics. In railroading we have long ago learned that long terms power delivery via overhead lines is by far the cheapest and best solution.
  - oxplot 4y ago
    I agree - trains make more sense than running overhead wires over highways.

digestives 4y ago

Engineering Explained made a good breakdown and analysis video on the physics of the truck: "Does The Tesla Semi Make Any Sense?" https://www.youtube.com/watch?v=Uv44W7xa4IU https://www.youtube.com/watch?v=Uv44W7xa4IU

yourapostasy 4y ago
The TL;DR of that great video goes against Betteridge's Law: yes it makes sense ("no fatal flaw found"), with the known information at the time Jason made the video. The charging infrastructure is likely not trivial, though; in the comments it was pointed out the infrastructure likely makes heavy use of batteries to avoid stressing out local substations and avoid abusing grid peaking.
- oxplot 4y ago
  > the infrastructure likely makes heavy use of batteries to avoid stressing out local substations and avoid abusing grid peaking From Tesla's presentation, it looks like that.
  - yourapostasy 4y ago
    Right, and that throws off calculations I've seen so far on Semi's ROI because I haven't been able to find out what that charging infrastructure costs per truck in a single truck scenario, two truck scenario, five truck scenario, and so on. MWh of batteries and the accompanying high-voltage installs do not come cheap, and there is maintenance and capex replacements associated with all that. As much as all that costs and as much electricity it gulps down, you might as well arrange with the utility providers to put in the marginal additional equipment to secure a discount for always consuming out of nuclear or similar baseload during low utilization periods, and only rarely charging batteries outside those periods, trying as much as possible to avoid tapping peaking plants' output. The lifetime TCO calculations for the charging infrastructure for full battery replacement included is going to be interesting to peek into. On a simplistic basis, that TCO plus the electricity costs would be put up against the cost of diesel, Diesel Exhaust Fluid (DEF), Diesel Oxidation Catalyst (DOC) catalytic converter, maintenance on the DEF and DOC subsystems, and so on. With my investor hat on, I still don't have the numbers I'd like to see to evaluate whether the truck is a slam-dunk ROI on short-haul routes.

abledon 4y ago

I can't wait till Munro and co take a look into this stuff. The amount of people already crapping on this is astounding.

oxplot 4y ago
Those whose opinion actually matter have done the math and put orders in to save them cost in the long run. Of course, if right now, the load capacity or the range isn't applicable to one's business requirements, then Tesla Semi doesn't make sense. However, cost is often the biggest driver in any business. If a business can change things around to fit within the current constraints of the Semi, then they can do a cost-benefit analysis and Tesla Semi may then make economical sense.
- oseityphelysiol 4y ago
  I expect the current orders to be PR motivated.
  - oxplot 4y ago
    Hard to tell, but given Tesla's historic record, demand for their products has only ever increased (discounting the current China situation which most likely has nothing to do with disparity between PR and actual product perf).
    - oblio 4y ago
      What's the "China situation"?
- SpelingBeeChamp 4y ago
  Pepsi’s order was placed in 2017.
  - oxplot 4y ago
    Not sure what you're implying with this. Specs have remained exactly the same and now, they've actually delivered on the spec they advertised in 2017.

afiori 4y ago

Some time ago I heard that the major obstacle to this truck is the weight. That is trucks in the US have a strict max tonnage and so the Tesla Semi can only be used to transport lightweight or not full cargo

sschueller 4y ago
Similar in the EU and Canada where the limit is 40 metric tons (88,000 lbs) vs the US where it is 80,000 lbs.

theluketowers 4y ago

I've been fascinated watching the progress of Edison Motors (https://www.edisonmotors.ca/ https://www.edisonmotors.ca/), who are making a diesel electric hybrid semi. Their logic and arguments make a lot of sense: the diesel engine gets to run at its peak RPM 100% of the time to charge the batteries - and it gets to take advantage of the perks of electric like regenerative breaking, quieter operation, and immediate torque. Not to mention the easier transition time when it comes to working within existing infrastructure. There's also all sorts of side benefits with what they're doing like the semi itself being a generator on wheels for heavy duty equipment. Lots of fascinating stuff coming from them, and they already have a driving prototype :)

oxplot 4y ago
The problem with hybrid vehicles in general is that they still rely on fossil fuels to some extent, so they're not a truly sustainable solution. And they have all the maintenance and reliability baggage of their fully ICE counterparts, something BEVs do away with. The time and money being spent on developing hybrid technology could be better spent on making fully electric vehicles more affordable and accessible. EDIT: and keep in mind, trucks are purchased with a long service life in mind (decades)
- theluketowers 4y ago
  While not perfect, they do meet real world needs in ways that are better than current ICE options. A fully electric truck isn't really a viable option in the market they're building for right now (heavy duty working trucks for logging, etc). Additionally, getting a working hybrid option out into the wild still benefits the eventual transition to fully EV trucks as it allows for testing and validating of the electrical systems required to make a functional workhorse that can deliver value to its owners / operators as well as pushes forward the viability & benefit of electric vehicles in the eyes of the public / industry.
- unethical_ban 4y ago
  They are a transition, to be sure, but especially for consumers who do 80% short trip and need the ability to do long trip, it would seem to ideal choice for the 2020s.

BatteryMountain 4y ago

Just use trains for bulk like a normal country.

oxplot 4y ago
It's all about economics. Whatever's cheaper wins. To that end, Tesla has mentioned in their presentations that a Tesla Semi convoy of only 3 trucks can be cheaper than a train for the same load.
- panick21_ 4y ago
  The problem is that highways are literally not cheaper but massively subsidized and heavy trucks are destroying that public infrastructure because they are so heavy. So just saying its all economics when the underlying rules of the game are totally unequal is not that useful.
  - oxplot 4y ago
    Sorry I should have been more specific. I'm referring to economics from the viewpoint of the business operating a fleet. Given almost all business do not hold back from whatever incentive and subsidies are available to them, it's fairly reasonable boundary to confine the comparison to.
    - panick21_ 4y ago
      Its a reasonable boundary but not reasonable when discussing the politics and what as a society should be done.
- me_me_me 4y ago
  > To that end, Tesla has mentioned in their presentations that a Tesla Semi convoy of only 3 trucks can be cheaper than a train for the same load. I can carry it on my magic carpet for even cheaper, trust me I am rich so I wouldn't lie... this time. Trains have replaceable engines, power-lines - no battery. Trucks will not be cheaper option no matter what mumbo jumbo techno jargon you throw at it. And decades of technological optimizations. And they dont need lithium to be made and maintained.

reillyse 4y ago

I always assumed the future of electric trucking would involve little battery trailers that could be quickly swapped out on a rolling basis by fleets of trucks. It seems the “refuel” paradigm makes sense for fuels where the majority of the fuel is consumed but maybe not as much for charging. With a network of truckers in the US a floating number of charging centers with batteries wouldn’t be that tough to create/maintain

Lutzb 4y ago
I worked for a company that builds electric trucks and that have also shown battery trailers with cargo space. The engineers told me that the coupling of the battery on the trailer with the semi caused them a lot of worries. High voltage/amperage combined with mechanical stress and failure scenarios (failing mechanical coupling of the trailer, destroying the battery connection). However it seems like the European companies heading this way.
_ph_ 4y ago
Yes, just exchanging batteries is an alternative to recharging. But it requires additional logistics and also the investment into additional batteries. There are of course scenarios, where battery change is the only practical way. Like it was with horse changes on long distance travel long ago. This changes quickly, if you have batteries with enough range to make recharging feasible. With electric cars the industry was quickly at the point and looking at the specs of the Tesla Semi, heavy trucks are basically there too. Which probably will kill any attempt at setting up a network for battery exchange before it was made.
oxplot 4y ago
> I always assumed the future of electric trucking would involve little battery trailers that could be quickly swapped out on a rolling basis by fleets of trucks. Maybe the future, but right now, I suspect the battery energy density is not forgiving enough for the battery to just be a carry load. Increasingly, the battery module is part of the structure of the vehicle and further works as weight to increase traction close to the drivetrain. There is also a lot of nitty-gritty details to do with safety, efficiency and cooling that makes moving the battery away from the Semi itself not a viable option ATM. Also keep in mind that at least for consumer cars, Tesla did try battery swap stations but nobody seemed to show any interest so they canned it.

codesnik 4y ago

I wonder if anyone considered trucking a swappable battery as well. That's not for semi, of course, but road trains do exist?

juurikas 4y ago

Hey all! I'm Jaan, the OP of the Semi article here. Great discussion already! I'm off the 'net for a few days but if you have questions or suggestions, hit me up on Twitter (@theEVuniverse) or on my email jaan/at/evuniverse.io. I also write a weekly EV industry newsletter which is where I uploaded this from. Cheers!

davidy123 4y ago

Disappointing there is not a word about safety to the outside world. I get they have to market to drivers, calling it a "beast," but large trucks are a great danger in terms of losing tires and, especially in cities, collisions. I see it is built with a scoop design so "things" (people, bikes, etc) hopefully don't get pulled under it so easily, but hopefully it also has advanced collision and awareness features suited to such a large vehicle. It is unfortunately typical of Musk to market to the aggressive impulse, rather than harmonious, even if his ultimate goals are beneficial.

thehappypm 4y ago
One of the biggest dangers of trucks is losing their brakes and going out of control. As the article points out, regenerative braking vastly reduces that problem. So that’s a safety win!

torginus 4y ago

Considering everyone tends to point out the Achilles heel of EV trucks is the high kerb weight limiting the tonnage of useful cargo, I find it really funny that their premier touted customer is Frito-Lay, whose products are universally referred to as bags of air.

oxplot 4y ago
Did a quick search. Diesel Semis' curb weight ranges b/w 10000lbs-25000lbs. The 10000lbs one may not be comparable in performance/range to Tesla Semi so keep that in mind. Tesla Semi based on the estimate in the article, is about 27000lbs.
caf 4y ago
Though their other launch customer is Pepsi whose products are cans of water.
- pwpw 4y ago
  Just to point out the obvious, Pepsi and Frito-Lay are owned by the same company, PepsiCo.

mukundmr 4y ago

I don't understand why you don't have companies like Tesla building fuel cell (hydrogen) solutions for commercial use cases. Here is an article that explains it - https://www.bmw.com/en/innovation/how-hydrogen-fuel-cell-cars-work.html https://www.bmw.com/en/innovation/how-hydrogen-fuel-cell-car... If Tesla can build a super charger network, they can build a hydrogen refilling network.

drexlspivey 4y ago
Here’s a video explaining the pitfalls with hydrogen as a fuel https://youtu.be/f7MzFfuNOtY https://youtu.be/f7MzFfuNOtY
sidcool 4y ago
From Elon's previous comments, Hydrogen is fundamentally not scalable and uneconomical.
- qubex 4y ago
  Setting aside Musk’s current plunge in credibility, his argument regarding hydrogen is predicated upon electrolysis. A vast network of transparent tubes and sunlight reflectors feeding genetically engineered microorganisms that release hydrogen would undermine that assumption, but transportation, storage, and energy density would indeed remain a problem.
jackmott42 4y ago
A charging network just requires some wire and electronics, everything is well understood and easy to do for experts in that field. Hydrogen on the other hand, is difficult to keep contained and cold enough to remain in liquid form. Even NASA who has worked with it for 50 years with massive budget and engineering expertise constantly has problems with it. For instance one of BMWs hydrogen cars you are not allowed to park in a garage! As hydrogen is expected to leak from it. And current hydrogen gas stations still suffer from this challenge. So hydrogen fuel cells do offer the advantage of better energy density for more range, but you have the dual difficulties of 1. how do I make the hydrogen efficiently AND cleanly and then 2. the infrastructure build out is actually as hard ad EV doubter think wires are.

bryanlarsen 4y ago

I wonder what kind of chargers Pepsico has installed. Sure, the ability to charge at 1MW+ is useful, but you won't want to use that often unless you want to spend all of your fuel cost savings replacing batteries. Just like a car, the battery will last a lot longer if you slow charge. But a slow charge on a 900kW battery is still a lot faster than you can get out of standard 240VAC. Pepsico probably wants to do 50-100kW overnight charging on their vehicles. I wonder if it's something like 1MW of power split between 8 stalls. So if one truck comes in during the day time, it can get a top up at 1MW, but overnight when there are 8 trucks parked, they all charge at 125kW or less.

zaptrem 4y ago
Charging a battery of this scale at 1MW likely won't have any more significant effect on life span than charging a Model whatever at a normal supercharger (which is negligible assuming thanks to battery temperature management and charge speed tapering).
- bryanlarsen 4y ago
  If you always charge at a Supercharger you will have a reduced battery life.

ksec 4y ago

The Link is dead? What happened?