The headline is clickbait. As 'twic pointed out, this means "no escort or any accompanying vehicles" [1]. It does not mean that the truck was self driving, which is strongly implied by the headline.
speaking as an automotive mechanic for a small chain of truck repair/wash stations across the midwest, I get how people could mistake it as a self driving truck but the fact that it made it across the US unescorted is a bigger deal than you think.
this means a driver managed pass every pre-flight check after stops, passed inspection stations in roughly a dozen states, weigh station checks despite also carrying a massive battery pack, and safety inspections from state troopers that likely had no clue what the hell it was. The truck was capable of hauling a commercial load. meaning the axle weight adjustments were properly executed and most importantly, Teslas answer to jake braking (engine braking) is a success. No truck, not even teslas, carries a braking system or air system with enough power to stop a downhill tractor trailer without shifting to a lower gear and employing the engine to help some. In my opinion, however tesla achieves this, is the real breakthrough.
> weigh station checks despite also carrying a massive battery pack
I'd hope an empty electric truck is light enough to pass the weigh station check. Else it would be useless when loaded.
> No truck, not even teslas, carries a braking system or air system with enough power to stop a downhill tractor trailer without shifting to a lower gear and employing the engine to help some.
A drivetrain that size should have impressive regeneration supplementing the mechanical brakes. Apparently this is about equal to engine braking in gas trucks. Though these trucks were empty.
I don't know about fully loaded but elecktrek has other articles where tesla said they were using it to pull loads between the giga factory in nevada and the main factory in california.
I don't think it's clickbait, because there haven't been any vehicles yet that did anything like that with self driving. You'd also use a car, not an experimental giant truck. It had a driver too. And used roads. I just don't see it as confusing. The key thing for this semi is that it seems to actually works, drives on regular roads, can be recharged at superchargers. It's a real vehicle.
All this really says is that Tesla has enough charging stations to drive coast to coast. That's progress. They're going to need huge charging stations at truck stops once this gets going, but that's OK.
I wonder when the day will come that you won't be able to drive long distances in a gasoline car without preplanning.
It’s a little more than that. It does confirm that there is a vehicle that is not total vaporware and is reliable enough to make this trip at least once. That’s something.
It doesn’t say anything about autonomy at all though, so readers looking for confirmation of that capability are not going to find much.
My Camry Hybrid has a 500+ mile range. It says "585 miles to empty" after a fillup but usually gets 540-550 miles in mixed driving. Maybe gas-only cars will someday have range anxiety.
funny, I never thought about this.. car took off when stations were numerous enough. As you say the day this parameter goes below a threshold ICE may drop in market value super fast.
US is ~3.1 million square miles. If driving 15 miles to the nearest gas station is considered reasonable that puts the minimum around 4,400 stations which is less than I expected.
Math is off as your driving along roads and you don’t need even distribution etc. But, this does suggest Gas is going to be viable down to ~5% of cars.
One of the services AAA used to offer was trip planning where they would identify gas stations and motels along your route so that you could get to where you were going without running out of gas. Once the interstate system was built, and at the same time a lot of gas stations got built at various off ramps, the number of gaps decreased to the point where few people today think about where they will get gas as they drive long distances, they just assume there will be one or more stations around.
One of the weirder possible futures is that enough progress is made on flow batteries such that you drive into what used to be a gas station and simultaneously dump your expended electrolyte while taking on charged electrolyte to continue your journey. Such a system would work well by having both a very quick charge mode (electrolyte substitution) and a more traditional (but slower) charge mode where you plugged into the grid.
...to visit an important potential customer rather than to carry loads of stuff. Must have been a fun day though for the office guys in the company HQ.
Hopefully there will be a bit more of this Tesla Truck on Tour going on, pleasing crowds all over the globe. I would go outside to check out a Tesla Truck if one rocked up in town. I would probably skip past F1 cars, fire engines and other novelty performance vehicles to do so.
It seems that the Tesla Truck is specifically for hauling big loads on very long distances rather than any other use case, with most truck manufacturers having half a dozen models with untold engine variants for the many other use cases.
I wonder if ultimately it does come down to economics, with the Tesla Truck having 'regen' as quite a trick to play. The 'regen' should make descending a lot safer and obviously a lot more 'green' than normal engine braking. I am intrigued as to how that will work out crossing The Rocky Mountains as per the customer visit going on here.
Deadheading[0] is probably easy on the battery. Yet even empty, the Supercharger network doesn't reach far enough yet, and apparently the truck had to take up several charging stations at "non-Super" chargers. Do things that don't scale, indeed.
> Musk jokingly added that they used a 1,000-mile long extension cord, but he is actually referring a system made of extension cords that they have used to charge Tesla Semi prototypes at Tesla’s regular charging stations.
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People who have witnessed Tesla Semi prototypes charging at Supercharger stations have told Electrek that the system made of extension cords plugs into several Supercharger stalls at the same time and into several charge ports on the truck.
Gas semi trucks can take 30 minutes to fuel, and electrics usually take vastly longer than gas vehicles to recharge. Megachargers will be the key to making these trucks actually viable. If they could get recharge times below refuel times, it would be a great advantage.
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> I wonder if ultimately it does come down to economics, with the Tesla Truck having 'regen' as quite a trick to play. The 'regen' should make descending a lot safer and obviously a lot more 'green' than normal engine braking. I am intrigued as to how that will work out crossing The Rocky Mountains as per the customer visit going on here.
Regenerative braking stops helping when the battery is full - on my Camry Hybrid, after going down about 600 feet of vertical drop, it actually starts the engine to engage engine braking.
Also, there's a limit in the rate of how much velocity energy can be converted to electricity by regeneration, per second. For instance, slowing from 65 MPH to 64 can take over a second using only regenerative brakes.
> apparently the truck had to take up several charging stations at "non-Super" chargers.
No, these were multiple connections to Tesla Superchargers - not ‘regular’ chargers. This is necessary because the Tesla Hyperchargers that are being developed to quickly charge the Semis are not deployed anywhere yet.
they have only announced them they will build them when the tracks are out. they have continually built their superchargers, keeping up with demand. this year with their incredible increase in vehicle production for the model 3 they have also increased their rate of new superchargers. See supercharge.info for some details. But it will still be hard for them to keep up with new vehicle production.
So how will they charge the numerous trucks they've sold before the full Megacharger network is available? Will a truck roll into a Supercharger and take up half the chargers?
It would be stupid for tesla to reduce charging opportunities which are a crucial need for a new truck. an example of how telsa deals with this is that tesla sells adapters so you can charge a tesla at a high speed chademo charger today, and also for j1772. tesla asked for a higher amperage j1772 standard that any car manuf. can support but only tesla really uses it (80 amp 220v).
A tesla can slow down much much faster than 1 mile an hour per second with regenerative brakes. As you said, if the battery is really full (like 99%, but not 80%) even on a tesla it uses regular braking when full, but once you drive a tesla 10 or 15 miles it has room to do regen braking. also you don't typically charge it to 100% every day, i only charge to the recommended ~90% - so i'm always ready for regen. You drive it in a certain mode where you don't need to use the brakes much, just take your foot off the gas pedal and it slows down rapidly. That's not good enough for say emergency stopping on the freeway but I don't need to emergency stop much.
But on a tesla at least the regen braking takes speed off much faster. there are two things at play, just taking off the power will start to slow you down, but you can see the breaking impact when you car is using negative power.
Kinetic energy increases at the square of velocity - so a 4400 lb car, accelerating from 64 MPH to 65 uses 7.25 KW, while going from stopped (0 MPH) to about 7 MPH uses slightly more, 7.75 KW.
It takes additional energy to add energy to a system that already has some energy. For example, recharging a partially-full battery from 70% to 90% will take more energy (or time) than charging from 5% to 25%.
At 65 MPH, it takes my Camry Hybrid over a second to absorb 1 MPH and reduce to 64 MPH, with only regenerative braking. At 35, it can absorb several MPH per second. Like a Tesla, the regenerative braking is always slowing the car down, but unlike a Tesla, it only regenerates at 5%-10% until the brake pedal is pressed, which is reflected by the "tachometer" dipping down into the blue CHG section.
> a 4400 lb car, accelerating from 64 MPH to 65 uses 7.25 KW
My Chevy Spark EV can regenerate at up to 60 KW. Forward drive tops at 100 KW. The regen limit is due to the battery charge rate, the bigger the battery, the more charge it can accept.
> It takes additional energy to add energy to a system that already has some energy. For example, recharging a partially-full battery from 70% to 90% will take more energy (or time) than charging from 5% to 25%
Why do you say "additional energy"? Do you mean "additional time", because that makes some sense as DC quick charging usually tapers off in rate as the battery becomes full. Please explain this if you actually mean additional energy as it is confusing.
Seriously. Tesla/Elon are one of the many dead horses around here that HN readers like to beat. There are other interesting things going on in the world.
I think if Tesla can pull this off, they will be in a great position. Self Driving cars are years away (I think), but I think self driving trucks are not.
I've driven down highways and passed massive distribution facilities that are just off the highway. It's a lot less complicated to have a truck drive along a highway, stop at a charger, and continue on to a distribution center. Low risk, boring, driving. If Tesla can role out a truck where they can say "It will cost $3,000 to move this trailer from our interchange facility (or the customers warehouse) here in North Carolina to our interchange facility here in Nevada in 24 hours" that's big.
I don't think you will be able to replace human drivers at every step (at the moment), but if Tesla can replace the long haul drivers- that's big. When the Electric Car market hits an inflection point, Tesla is going to be playing catch up but if they can get into trucking before anyone else does, and with a solid long haul self driving truck, we're going to see a lot of chance.
Autonomy in trucking is going to be _much_ easier because it will initially be performed in convoys: one human driver up front and several autonomous trucks following. So you can easily get 80% of the cost benefit in a much safer situation.
"Tesla Semi made it 'across the country alone'" in the title does imply that it was self driving though the article clarifies that in this case 'across the country alone' actually means with only battery power and connections to SuperChargers.
None of this refutes poster's point of the greater value and likely simpler use case for automated trucking versus the consumer transportation market. It just makes them not relevant to this particular article.
In the embedded tweet [1], Musk clarifies that "alone" means "no escort or any accompanying vehicles". Which seems like a pretty unimpressive feat to me.
Seems OP thought 'made it alone' means without driver - self driven while it's actually without conventional fuel but just battery power alone. But OP's point is what Otto set out to solve, I guess and now Anthony is starting a church
1 = https://news.ycombinator.com/item?id=17842679