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I have also ran similar calculations in my head. I think what I'd want to be convinced is a thorough analysis from a mechanical/industrial engineer on how much

I have also ran similar calculations in my head. I think what I'd want to be convinced is a thorough analysis from a mechanical/industrial engineer on how much you can expect to save from a fully electric car on maintenance. The claim I've heard from Tesla is that, since there are much fewer moving parts within an electric motor, the car will last substantially longer. While this makes intuitive sense, I would love to see a breakdown of the actual numbers. Gas savings are pretty easy to calculate. That said, there is one more factor I had considered, for fun. If Tesla continues to deliver more cars and eventually electric cars dominate the new car market in 5-10 years, I would imagine the Model S would be worth an investment as a "classic" car. If you maintained it well, I wonder if the actual value of the car would have a chance of appreciating at a much higher rate past, say, 50 years.

jesusmichael 13y ago
The statement that electric motors have fewer moving parts so they last substantially longer is a fallacy that electric car proponents have been spreading for years. There are still many, moving parts which require servicing and can fail at a rate of similarly serviced gas engines. In fact servicing (rewinding) is quite a labor intensive and expensive operation, given the price of copper or other conductive material used in the construction of electric motor. Should a motor fail. The cost is significant. I like the idea of an electric car, but the truth is the motors do fail. They require maintenance in the static environment of a factory or they will fail, a car on the open road with harsh environmental factors it will be hard on them. But the biggest lie about electric car maintenance is that is lower. Its not. 90% of a vehicle's maintenance has nothing to do with its motor. It's tires, brakes, lighting, lubricants(yes electric motors need oil changes too), and power systems. Which I suspect will be more extensive here since there will be countless OS upgrades to both the drive systems and the power control units. Its not possible at this time to compare gas engine maintenance w/ electric motor maintenance because its not apples to apples. You can however look at replacement cost as an indication of serviceability. A 400hp electric motor costs about $24,000 vs. a 400hp gas engine at about $6000. The gas engine is still far more economical at this point even factoring in fuel costs.
- mikeash 13y ago
  Tesla doesn't seem to think their motors require oil changes. Are you saying that they're just letting their owners destroy the motors by going without necessary maintenance? Also, do you have a source on the $24,000 for their motor? That seems awfully high given that the thing is about the size of a loaf of bread. Hard to see what could make it so expensive.
  - 001sky 13y ago
    http://media.caranddriver.com/images/media/51/under-the-teslas-skin-2013-tesla-model-s-january-2013-issue-large-photo-493014-s-original.jpg http://media.caranddriver.com/images/media/51/under-the-tesl... In addition to the motor, the schematic diagrams above seems to many moving parts that typically need work by 120,000 miles. Eg: steering (likely) differentials (likely) and in various parts of the suspension (internal). Whilst the specifics may be debatable, most of these items are wear items and require fluid changes and/or replacement internals. Things also like wheel bearings will need some preventive maintenance. If this spreadsheet was for a 50,000 mile interval or a lease perhaps you'd overlook these. A chassis for $30K+ with 120k on the clock would bring customers looking at the cost of these services, I would venture. One way luxury brands (at least in the past have) maintained the price premium of their new vehicles is to make the 100K and up maintence quite expensive.
    - mikeash 13y ago
      That's nice, but I'm specifically wondering about the motor "oil changes" and the cost of the motor itself, and this doesn't address that at all.
      - 001sky 13y ago
        What's your theory on how they lubricate the spinning parts?
        mikeash 13y ago
bsilvereagle 13y ago
> fewer moving parts I think auto makers use this to distract potential buyers from what's really going to be replaced: the battery. Just like laptop batteries, the charge life of the car battery is going to decrease with time. Tesla did have this on their website, but the link this is quoted from is broken: "A Battery Replacement Option will be available for purchase soon. The option allows you to pre-purchase a new battery to be installed after eight years for a fixed price: $8,000 for 40 kWh batteries, $10,000 for 60 kWh batteries, and $12,000 for 85 kWh batteries." http://www.teslamotors.com/it_IT/forum/forums/battery-replacement-cost-0 http://www.teslamotors.com/it_IT/forum/forums/battery-replac...
- bsdetector 13y ago
  The $12k battery placement cost is not included in the spreadsheet, not to mention that this is the cost if purchased 8 years ahead of time and purchasing it later will probably be more expensive. He's already bought the car and so he should know how his insurance cost has changed, but doesn't mention how much it changed. The model also does not include property tax. I'm assuming California has a car property tax of some kind. ...so basically this is justifying his purchase to himself, little more than that.
  - morganvachon 13y ago
    >...so basically this is justifying his purchase to himself, little more than that. I don't see where he said otherwise.
    - thefreeman 13y ago
      I think making a domain entirely dedicated to it is evidence that it wasn't intended as just self justification. edit: On further thought, maybe not. It does seem to be the trend to do websites for a single topic or piece of writing. I would still take it as indication you are presenting it to others though.
      - morganvachon 13y ago
001sky 13y ago
The spreadsheet seems light on maintenance numbers. The car is sold in year 8 but hasn't been serviced in several years previous (seems odd). Most people correct for this come the residual. Also, the tires on this car wear out quickly. 120k miles would see at least 6x sets of tires in the back (some are going in under 10k miles), and likely 4 in the front (20x$400=8,000). Also, the Battery is expensive and shoudl be replaced around 100K most likely ($8,000+). These costs would be substantial in total, but the author also forgets Insurance. We've seen Tesla re-design the underbody most likely for insurance rather than pure safety reasons. This is likely ($15-20K) of omitted cost. Lastly, brakes are typically replaced @ 30K miles and on a car of this caliber would be ($4,000) over this timeframe. That is another $40,000 out of pocket on the back of a napkin. It could be more or less, but the spreadsheet shows <$4,000 which seems off by an order of magnitude.
- mikeash 13y ago
  Tesla brakes last practically forever because they're almost never used. Regenerative braking is used for normal driving and the mechanical brakes are just there for hard braking, emergencies, and possibly at very low speeds. So I think you can take that back out of your numbers. Leaving out insurance seems really bizarre though.
- pakile 13y ago
  Tesla offers the option to purchase 4y of maintenance for $1900, which I included in the model, vs. $600/yr. The options are nearly economical neutral, but I plan to do at least the 1st 4y option. Maintenance also includes brake pad replacement. I did not include tires or insurance - either for the Tesla or for the other vehicles (Ody, BMW, Volvo). I also didn't include the financial value of safety (though Travis attempted to on the cash flow model), HOV lane access, cargo space, etc. On the battery, based on the research I've read from existing EV owners, and from my experience as an EV owner for 3y, I'm expecting around 85% of my battery to be available in 8-10y. If a battery swap option is available, I plan to do it around year 15 or so (i.e., ~2030).
  - bri3d 13y ago
    Why didn't you include tires or insurance? Tires for a Tesla (especially with the larger-wheel packages) will be enormously more expensive than those for an Odyssey, and the car will wear them out much more quickly. On a low maintenance gasoline engine (i.e. not VW/Audi), consumables like tires, brake pads+rotors, dampers, wheel bearings, ball joints, and so on outweigh the ICE specific costs like oil filter and change, spark plugs, serpentine belts, timing belts, and water pumps by a decent margin, doubly so if the engine has a well engineered timing chain system and thus doesn't require an involved timing-belt service. Plus, an electric car still has plenty of moving powertrain parts like water pumps and valves that could fail, and we don't know if that will happen yet. Tesla are at a huge advantage in this department, though, because they've accustomed their clients to being tracked at all times and their cars are all serviced at Tesla-owned service centers. That means that if any failure patterns become evident, Tesla can summon their owners to have the issue fixed proactively before it becomes a problem. I love this model and do think it adds a lot of value to the Tesla, but whether or not they can sustain such a program at scale remains to be seen.

jesusmichael 13y ago

The statement that electric motors have fewer moving parts so they last substantially longer is a fallacy that electric car proponents have been spreading for years. There are still many, moving parts which require servicing and can fail at a rate of similarly serviced gas engines. In fact servicing (rewinding) is quite a labor intensive and expensive operation, given the price of copper or other conductive material used in the construction of electric motor. Should a motor fail. The cost is significant. I like the idea of an electric car, but the truth is the motors do fail. They require maintenance in the static environment of a factory or they will fail, a car on the open road with harsh environmental factors it will be hard on them. But the biggest lie about electric car maintenance is that is lower. Its not. 90% of a vehicle's maintenance has nothing to do with its motor. It's tires, brakes, lighting, lubricants(yes electric motors need oil changes too), and power systems. Which I suspect will be more extensive here since there will be countless OS upgrades to both the drive systems and the power control units. Its not possible at this time to compare gas engine maintenance w/ electric motor maintenance because its not apples to apples. You can however look at replacement cost as an indication of serviceability. A 400hp electric motor costs about $24,000 vs. a 400hp gas engine at about $6000. The gas engine is still far more economical at this point even factoring in fuel costs.

mikeash 13y ago
Tesla doesn't seem to think their motors require oil changes. Are you saying that they're just letting their owners destroy the motors by going without necessary maintenance? Also, do you have a source on the $24,000 for their motor? That seems awfully high given that the thing is about the size of a loaf of bread. Hard to see what could make it so expensive.
- 001sky 13y ago
  http://media.caranddriver.com/images/media/51/under-the-teslas-skin-2013-tesla-model-s-january-2013-issue-large-photo-493014-s-original.jpg http://media.caranddriver.com/images/media/51/under-the-tesl... In addition to the motor, the schematic diagrams above seems to many moving parts that typically need work by 120,000 miles. Eg: steering (likely) differentials (likely) and in various parts of the suspension (internal). Whilst the specifics may be debatable, most of these items are wear items and require fluid changes and/or replacement internals. Things also like wheel bearings will need some preventive maintenance. If this spreadsheet was for a 50,000 mile interval or a lease perhaps you'd overlook these. A chassis for $30K+ with 120k on the clock would bring customers looking at the cost of these services, I would venture. One way luxury brands (at least in the past have) maintained the price premium of their new vehicles is to make the 100K and up maintence quite expensive.
  - mikeash 13y ago
    That's nice, but I'm specifically wondering about the motor "oil changes" and the cost of the motor itself, and this doesn't address that at all.
    - 001sky 13y ago
      What's your theory on how they lubricate the spinning parts?
      - mikeash 13y ago

bsilvereagle 13y ago

> fewer moving parts I think auto makers use this to distract potential buyers from what's really going to be replaced: the battery. Just like laptop batteries, the charge life of the car battery is going to decrease with time. Tesla did have this on their website, but the link this is quoted from is broken: "A Battery Replacement Option will be available for purchase soon. The option allows you to pre-purchase a new battery to be installed after eight years for a fixed price: $8,000 for 40 kWh batteries, $10,000 for 60 kWh batteries, and $12,000 for 85 kWh batteries." http://www.teslamotors.com/it_IT/forum/forums/battery-replacement-cost-0 http://www.teslamotors.com/it_IT/forum/forums/battery-replac...

bsdetector 13y ago
The $12k battery placement cost is not included in the spreadsheet, not to mention that this is the cost if purchased 8 years ahead of time and purchasing it later will probably be more expensive. He's already bought the car and so he should know how his insurance cost has changed, but doesn't mention how much it changed. The model also does not include property tax. I'm assuming California has a car property tax of some kind. ...so basically this is justifying his purchase to himself, little more than that.
- morganvachon 13y ago
  >...so basically this is justifying his purchase to himself, little more than that. I don't see where he said otherwise.
  - thefreeman 13y ago
    I think making a domain entirely dedicated to it is evidence that it wasn't intended as just self justification. edit: On further thought, maybe not. It does seem to be the trend to do websites for a single topic or piece of writing. I would still take it as indication you are presenting it to others though.
    - morganvachon 13y ago

001sky 13y ago

The spreadsheet seems light on maintenance numbers. The car is sold in year 8 but hasn't been serviced in several years previous (seems odd). Most people correct for this come the residual. Also, the tires on this car wear out quickly. 120k miles would see at least 6x sets of tires in the back (some are going in under 10k miles), and likely 4 in the front (20x$400=8,000). Also, the Battery is expensive and shoudl be replaced around 100K most likely ($8,000+). These costs would be substantial in total, but the author also forgets Insurance. We've seen Tesla re-design the underbody most likely for insurance rather than pure safety reasons. This is likely ($15-20K) of omitted cost. Lastly, brakes are typically replaced @ 30K miles and on a car of this caliber would be ($4,000) over this timeframe. That is another $40,000 out of pocket on the back of a napkin. It could be more or less, but the spreadsheet shows <$4,000 which seems off by an order of magnitude.

mikeash 13y ago
Tesla brakes last practically forever because they're almost never used. Regenerative braking is used for normal driving and the mechanical brakes are just there for hard braking, emergencies, and possibly at very low speeds. So I think you can take that back out of your numbers. Leaving out insurance seems really bizarre though.
pakile 13y ago
Tesla offers the option to purchase 4y of maintenance for $1900, which I included in the model, vs. $600/yr. The options are nearly economical neutral, but I plan to do at least the 1st 4y option. Maintenance also includes brake pad replacement. I did not include tires or insurance - either for the Tesla or for the other vehicles (Ody, BMW, Volvo). I also didn't include the financial value of safety (though Travis attempted to on the cash flow model), HOV lane access, cargo space, etc. On the battery, based on the research I've read from existing EV owners, and from my experience as an EV owner for 3y, I'm expecting around 85% of my battery to be available in 8-10y. If a battery swap option is available, I plan to do it around year 15 or so (i.e., ~2030).
- bri3d 13y ago
  Why didn't you include tires or insurance? Tires for a Tesla (especially with the larger-wheel packages) will be enormously more expensive than those for an Odyssey, and the car will wear them out much more quickly. On a low maintenance gasoline engine (i.e. not VW/Audi), consumables like tires, brake pads+rotors, dampers, wheel bearings, ball joints, and so on outweigh the ICE specific costs like oil filter and change, spark plugs, serpentine belts, timing belts, and water pumps by a decent margin, doubly so if the engine has a well engineered timing chain system and thus doesn't require an involved timing-belt service. Plus, an electric car still has plenty of moving powertrain parts like water pumps and valves that could fail, and we don't know if that will happen yet. Tesla are at a huge advantage in this department, though, because they've accustomed their clients to being tracked at all times and their cars are all serviced at Tesla-owned service centers. That means that if any failure patterns become evident, Tesla can summon their owners to have the issue fixed proactively before it becomes a problem. I love this model and do think it adds a lot of value to the Tesla, but whether or not they can sustain such a program at scale remains to be seen.