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> I'd say you are off by an order of magnitude.

On what basis? I know he didn't cite, and I'm not trying to put the burden of proof on you, but I'm curious why you think this. As in, I'd like to see some data (from either side).

I did some brief searching and he is correct that [45]00 HP brushless motors seem to go in the low five figures (at least on Ebay, which I know is not representative of Tesla's costs). I'm happy to believe Tesla's cost less, but I'm not sure.




On the basis that it is the size of a (very large) watermelon. What's it made of? Copper and steel and aluminum. $1000 of materials and $1000 in labor.

Here's a pic: http://insideevs.com/wp-content/uploads/2014/12/Screen-Shot-...

Then of course there is the cost of the cooling jacket and the electronics. I can't estimate that readily.


This manner of cost estimation is not convincing to me, for reasons that should be obvious to anyone. There are plenty of small things that cost a lot of money, because, perhaps, of the precision or techniques required to manufacture them or their components, or the dearness of the materials that compose the minority of the object.

TL;DR: What is a sub-one ounce object made mostly of silicon that costs more than a thousand dollars. http://www.newegg.com/Product/Product.aspx?Item=N82E16819116...


>TL;DR: What is a sub-one ounce object made mostly of silicon that costs more than a thousand dollars. (intel i7)

In that case, you are paying for the IP, not the silicon.

The Tesla motor is a simple design, no magnets, no brushes. I assume they are hand-built. Some, but not too much precision machining required.

Think about how much precision goes into a 2TB hard drive that costs $100 retail.


I often come to the wrong conclusion when "just thinking" about it, especially in domains where I am not even a novice. Also, the fact that I don't find listings for 500hp brushless motors for <10k online calls into question the results of your thought experiment.

I can see where you get your belief -- I wasn't questioning that it is a reasonable one to hold. But I am asking for evidence that compels me to a confidence level I'd actually bet on. Data will be required. Thought experiments are not sufficient.

(Don't get me wrong, I'm not accusing you for failing to provide data. It may not be publicly available. And it is not your duty to give me this. But that is what I am asking for, and if you don't have it, you don't have what I want, your duty or no.)


You're making an assertion that runs counter to the common wisdom that electric cars will require less maintenance, so the burden of proof is on you.

The fact that you can't find brushless motors online that retail for less than $10k is not convincing, because it's a new use case, a unique design, and they're not selling them outside of cars. You don't know what the pricing is. As far as materials, that amount of copper isn't going to help it get to $10k.

EDIT: Oh sorry, I mistook you for the originator of this thread, jesusmichael. He asserted that, not you.


So your logic tells you that Tesla has "invented" an electric motor, so rugged that it can withstand that riggers of being inside a consumer vehicle on the open road with a novice operator, in various environmental conditions, that is a fraction of the cost of similarly powered electric motors that operate in static environments, such as a factory floor, with experienced operators and fixed maintenance schedules? Wow.. I have a bridge to sell you... you're not the guy to be discussing "common wisdom"...


You're bringing up a lot of irrelevant stuff.

Novice operator - the operator of the motor itself is the control electronics, not the driver. If the operator can do something to damage the motor, the design is faulty.

Industrial electrical motors and control electronics like those in robots have completely different tolerance requirements, and are made in relatively low volumes, and so there are fewer units to support development costs.


relatively low volumes? Nearly every machine in every factory in the world has an electric motor of some ilk.. Have you ever been in a factory?

The novice operator and put the machine itself in a situation in which it will not operate correctly, extreme cold, flood, etc. Steep grade + Lead Foot = burnt coil. While I do agree with you to some extent... there is some user input... but motors in Tesla... are still pretty complex..


I meant that the individual models of industrial motors are made in low volumes relative to the motors in a mass manufactured product like the Model S, not that there weren't many electric motors in industry. There obviously are quite a lot of them involved in industry, but they come in many types, each of which has to pay back its own development budget.


I never made that assertion. I'm only asking questions.

"Common wisdom" does not create a burden of proof for detractors, especially if the common wisdom is never, that I can find, backed up with evidence. That is absurd. It would be like saying that the burden is on non religious people to prove that Jesus is not god because billions of people think he is.


Yeah, sorry about that, I got you mixed up with another poster.

But I do think that it's backed by evidence. There's no multi-gear transmission, and while there are moving parts, and other than the wheels/brakes, they aren't bathed in liquids that need regular changes and they aren't subjected to combustion and various other destructive forces that an ICE is constantly subjected to. There's relatively little force transmission hardware needed. The motors themselves should be relatively low-friction, and mechanically are much, much simpler than internal combustion engines (compare a breakdown of the parts of an ICE vs. electric motor, they're in completely different leagues). Air-fuel mixture control, turbochargers, and all manner of other chemical energy management systems are replaced by solid state electronics.


As to your i7 costs, lets conveniently ignore the costs of the FAB, the equipment to make that small little piece of silicon is enormously expensive


What about volumes of scale?


It doesn't cost $1000. What you're paying for is R&D. Just like a Windows 8 DVD doesn't cost hundred of dollars to make


The implicit claim being that Tesla does not factor in R&D when they charge consumers for replacements?


No, just pointing out that processed silicon does not cost Intel anything close to $1000.

Also I doubt R&D cost for an electric motor is high because the technology is mature.


Given how vertically integrated Tesla is, this is the right approach. Include a factor for time on capital equipment (number which can be produced per year per machine, cost of machine, cheap cost of capital, wear on machines, depreciation over lifetime) and you'd probably be good (maybe $3k total for the part?)

If it's a commodity item (like most electric motors, but maybe not the one in the Tesla), with a competitive market, you might be able to estimate cost by looking at open market pricing, but for something like SpaceX, that clearly doesn't work.

Tesla is closer to SpaceX in thinking than it is to most car companies, especially startup car companies.


The entire car is only about twice that, and we know the battery is very expensive. There's no way the electric motor costs $24k.


Here's one on Ebay for $10k.. Ebay! http://www.ebay.com/bhp/300-hp-electric-motor

General Purpose 350HP motor. $25K http://www.globalindustrial.com/p/motors/ac-motors-2-phase/3...

In general these motors have tight tolerances and aren't the motors in your electric shaver

The entire car cost $70K...


Referring to your 350 hp example:

1. That motor is a low speed motor, as such it is massive. It weighs 3044 pounds. The Tesla motor runs at nearly 10 times the speed, and ought to be roughly a factor of 10 lighter. 2. See how the price drops by almost 10% when you buy more than 5 of these motors? Now imagine you are buying 20,000+... 3. You can bet the manufacturer of the motor (Baldor) did not get $25k for it. I imagine the markup for the reseller is of the order of 30-50%, on top of other costs such as transport. These do not apply to Tesla.

I am pretty sure even $6000/unit is an over-estimate.

I have some information from an occasionally reliable source that the entire car costs around $20,000 to make. This is the "incremental cost", after tooling, R&D etc has been paid for. This is apparently about the same as a top level mass produced luxury Benz - for the Benz, the much higher inherent production cost is offset by the scale and efficiency of their production line.


The comparison is retail to retail... Not wholesale cost. I'm sure if you need a motor, because yours failed after 6 years, they aren't going to sell it to you for wholesale. And if they are marking up the cost of the car by 400% than if their motor is $5000... you'll be paying $20k


Analysis estimates of the cost of the car are about $56K

http://green.autoblog.com/2014/02/26/why-teslas-35000-model-...

That $20k motor is much less advanced than what's in a Tesla... So @ $24k I think its a bargin... what is the rest of the car? Aluminum and Plastic and a couple of computers...


In that range the price usually includes the controller and associated power electronics, which is a significant fraction of the cost.




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