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Tesla Semi

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Re: Tesla Semi

#551

"The quickest acceleration—from zero to 60 mph in 20 seconds, fully loaded." sound of cargo falling over :P But serious question: how important is acceleration for trucks?

May have been a joke but 20 seconds is still really slow. I had a van that took 13 seconds on paper (although I never actually verified that) and the contents we never in danger of being tossed around.

Re: Tesla Semi

#552
post #214

Earlier quoted context omitted.

"Well, it's a fraction of the cost to operate, but if a tire blows, the mechanic will have to detach a piece of plastic. So I think we'll pass."

Don’t worry, when the tire blows it’ll take that fiddly piece of plastic with it. Which I think is at least part of parent’s point.

And the 99.9% of time when the truck is running with all tires intact, that fiddly piece of plastic gives, say, extra 5% of fuel efficiency. Even if it requires a complete replacement every time a tire blows, it may be worth having.

Re: Tesla Semi

#554

Ok as a mechanic a few million questions: * What happens when a wheel seal goes? Do I have to remove all that ridiculous plastic on #2,3 axels?? * What happens when a tire blows? Is it going to destroy all that plastic and take out a few more tires in the process? * Why all the glass? I've spend entire days replacing windshields for a 12 or so truck shop which generally come in two (drivers and passengers), the Tesla…

Why do you worry - only Tesla authorized service will be allowed to repair the truck

Re: Tesla Semi

#555

Earlier quoted context omitted.

Then it's dead out of the gate, almost every trucking company in existence does in house repairs due to cost.

Call me a fanboy, but something tells me that the guy who built a revolutionary space program from scratch while successfully running a revolutionary auto company, probably has some ability to think things through pretty comprehensively from all angles and plan effectively for what's needed. Do you think you've just pointed out something that never occurred to him? Do you think if you could share your comments with h…

its a cult of one man and a pity that the man in question still wants to take all the credit i wonder who will take the blame when time comes

Re: Tesla Semi

#556
post #384

Earlier quoted context omitted.

Pretty sure Model 3 production is going amazingly well, yeah. Astoundingly well. But the media's portrayal of it has people convinced otherwise. Let's try this perspective instead: "Decade-old electric car company moves up plan for mass production of new affordable long-range sedan by 2 years" And then ask ourselves, after moving it up by 2 years, does a 3-month delay mean "things are going badly"? If I say I'm going…

> If I say I'm going to leap 500 feet, and then I leap 450 feet, do you say I failed? Yes, that's what the word failed means.

and if your leap is 1 foot instead?

Re: Tesla Semi

#557
post #323

Earlier quoted context omitted.

> If you check out the reveal, you'll see that it doesn't have those rediculous covers https://tctechcrunch2011.files.wordpress.com/2017/11/tesla-s... ? I'm not sure what you mean. Looks about the same as the linked page to me. > nor does it have near zero clearance between the cab and trailer which would prevent articulation, and nor does it have near zero ground clearance. https://i.imgur.com/cECtzId.png https://i.…

Odd, the article I read had this image: https://c1cleantechnicacom-wpengine.netdna-ssl.com/files/201... (or one like it), and looking at the video, it seems they had both on stage? Are there two models? It didn't seem to be discussed.

They had two on stage. One tall, one less-tall. That's the latter.

Re: Tesla Semi

#558
post #490

Earlier quoted context omitted.

Is that possible? Assuming 500 miles of range at 2kwh a mile is a 1000kwh battery, charged over 30 minutes, is 2 megawatts, if the voltage is the same as the supercharger (480V) requires 4000 amps...

Google says your average powerline carries 10k amps.. so it seems within reason, but it would require some power upgrades ;)

Power = amps × voltage . So no. They are 10kA × 3kV (well, depends on the line), so that gives us 30MW.

Re: Tesla Semi

#559

Earlier quoted context omitted.

30 square meters, laying flat. So maybe 3kW. While the engines need more like 100kW. You can't effectively power any vehicle with 15% efficient solar panels.

No, but you can improve the range by a few percent.

until you consider the weight of the solar panel

Re: Tesla Semi

#560

Earlier quoted context omitted.

There will always be situations where you can no longer recover energy, fully electric or hybrid. Your battery could be full, or overheating. At that point, you have to waste the energy. I believe the normal way to handle this scenario is to just fall back to mechanical braking.

Why do most/all electric and hybrid cars have regenerative braking while ICE cars don't? It's because, as the GP said, the battery would be quickly topped up and extra energy wasted. Only electric vehicles doing frequent stops/downhills can make productive use of regenerative braking. Potential energy lost by a truck going 10 m (vertically) downhill: 40 000 kg * g * 10 m = 4e6 J. Capacity of car starter battery: 40 A…

To drive the point home, a Swiss company is working on a mining truck that will be a net generator of electricity - it goes up the mountain empty, but when it goes down it is full of heavy ore, and regenerative breaking charges the batteries more than was used to climb the mountain. The extra 10kWh can then be fed back into the grid.

https://arstechnica.com/cars/2017/09/this-cement-quarry-dump...

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