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Tesla Semi

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481–490 of 575 posts

Re: Tesla Semi

#481

Anyone else find it odd they don't talk about the battery? 500 miles of range at 2kwh a mile is a 1000kwh battery which is 10 model S batteries. Model S battery weighs 1,200 lbs lets assume they somehow improved on that by 20-30% so this is a 10,000 lb battery. Not sure how much the motors weigh, the Tesla motor and inverter are about 350lbs so lets say another 1000lbs. A Diesel engine, transmission and fuel for 500…

If you take the Model S and scale it up then people have said the battery is half the cost of the car, and therefore the battery alone is roughly the cost of a normal car. I don't think it would be suprising if the same is true for the semi. There's at least one rural delivery man who bought a Tesla Model S and paid for it by using the mileage payments he gets for his job. So as long as your route fits, the same kind…

There's at least one rural delivery man who bought a Tesla Model S and paid for it by using the mileage payments he gets for his job.

There's a specific tax deduction for commercial vehicles that cost more than $50000.

Re: Tesla Semi

#482
post #421

:/ The centre driving location, not sure if that is a terrible idea for pedestrian and bicycle safety. Or the opposite as closer to the other side. Guess time will tell if a lot gets squashed against fences like bikers often do in London.

London already has a terrible problem with extremely narrow (and often jagged) roads.

As an American many of the streets were hell to navigate, and I understood why tiny cars are valued there

Re: Tesla Semi

#483

Earlier quoted context omitted.

It wasn't really from scratch though was it, he hired out people who had already worked with space projects. None of the tech is really new (yet). We used to have the same types of rockets in the past. Amongst Model 3 fiasco Solarcity too currently has issues.

The entire reusability thing was not really a thing before spacex

Wasn't the space shuttle and it's SRBs reusable?

Re: Tesla Semi

#484

Earlier quoted context omitted.

Elon Musk decided that spending days or a week preparing for a presentation is not the best use of his time. At least that much time is generally what it takes to pull off a really smooth presentation. I heard that he does not script them and just does them off the top of his head. Tim Urban has a great essay about different levels of prep people do for talks [1] which he wrote when preparing to give a Ted talk. Musk…

Considering Tesla is depending on it's image to get more money to fill the gap of it's ever deepening losses, spending days preparing a presentation is the best use of his time. Tesla has a price-to-sale ration of nearly 6, while Nissan and GM are <0.5. So Tesla is mostly image and vision, not reality. Therefore it depends on Musks presentations with visions of a glorious future.

Or maybe Tesla's "image and vision" stem from its founder's tendency to completely ignore sideline commentary on non-substantive issues and focus on product.

Re: Tesla Semi

#485
post #296

Earlier quoted context omitted.

I took an interest in this and looked up "retarder" on Wikipedia and it mentions engine braking (and exhaust braking), hydraulic retarders and electric retarders which are eddy current brakes more commonly used in the railways. Which one are you referring to? According to the article, most commonly these are not used for regenerative braking, the energy is wasted as heat instead. Eddy current brakes can be used for r…

Sorry, for not checking Wikipedia. Because I work in the industry as an electrical engineer defining standards, and owning a historic truck myself just for fun, because I can. Originally, it is right that retarders were introduced to just having a non-destructive brake by just wasting the energy. That was around the 1980s. This was just to save maintenance cost as brakes were a big part of that costs. The trucking in…

Regenerative brakes in an electric car use the engine, and add no weight and no complexity.

Re: Tesla Semi

#486
post #421

:/ The centre driving location, not sure if that is a terrible idea for pedestrian and bicycle safety. Or the opposite as closer to the other side. Guess time will tell if a lot gets squashed against fences like bikers often do in London.

Also don't like that there aren't passenger seats, or at least they don't show in the interior pictures.

On a YouTube stream we were watching, I saw at least one fold down passenger seat in the truck cabin. Not sure how comfortable it would be, though.

Re: Tesla Semi

#487

Earlier quoted context omitted.

I assumed it meant "nonspecifically, but impressively, tough."

Like my fist has the power of a supernova explosion?

Is your fist's energy not a derivative of the big bang itself? Where did you think your fist got its energy from?

Supernova would be underestimating the power of your fist. Truly think about the history of the energy of your system!

Re: Tesla Semi

#488

Earlier quoted context omitted.

It would be a slow rollout anyway. First customers would be people with ~200 mile routes, just charge at home base. Then people with ~500 mile routes that can charge at both ends. grow from there.

It looks like the first big buyer is using them for those short-haul trips. Does the Semi have a sleeper cab? If not, it won't be used on long-haul routes regardless of battery.

What's required for a sleeper cab? We got some shots of the interior and it looked easily big enough to add a bed or the like. With a battery that big heating overnight should be practically free.

Re: Tesla Semi

#489
post #214

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…

"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."

This dismissive attitude of a domain expert's opinion while taking Musk's/Tesla's word on revolutionary claims that they don't even have a working prototype of yet is a perfect example of why the court of public opinion is slowly starting to turn on Silicon Valley

Re: Tesla Semi

#490

Earlier quoted context omitted.

At 7 lbs a gallon for diesel most semis can carry 200 gallons so add an extra 1000lbs if you like, the Tesla still has to make up 5000 lbs while having 1/3rd the range. Timing stops for megachargers will be a whole lot more difficult than truck stops until they are as ubiquitous. If you have to use a plain old supercharger your talking 8-10 hours for a charge, don't even bother with a normal plug of any kind.

Elon says that the truck will be charged by the end of the 30 minute DOT required break (14:06 into the livestream: https://livestream.tesla.com/ ).

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...
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