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SByer
'08 #383
Ok, this thread has gotten off topic, and I don't want to add to the mess, but...
The article in the paper this morning listed the top states by amounts of solar added. CA was first, of course, but second was... New Jersey!
The article in the paper this morning listed the top states by amounts of solar added. CA was first, of course, but second was... New Jersey!
mt2
Member
I wouldn't. My thought is you should only list those items that are different between an ICE and an EV. Of course you should note that total cost of ownership will be higher on both vehicles. You can fudge some numbers for cabin filters, headlamps and the like and then add them to the bottom line of both cars. But I wouldn't muddy the water by blending costs that are the same with costs that are different.
shark2k
Member
Got a problem with that :tongue:. The reason for that though is because of the subsidies (mainly the SRECs).
Ok back on topic :biggrin:.
-Shark2k
Are you factoring battery replacement? I've seen the bits Tesla touts about EV cars having much lower maintenance costs, but it sort of glosses over the battery replacement around 100,000 miles. I've seen some estimates it's $25-40k depending on the size (How Much Does a Tesla Model S Battery Pack Cost You? We do the Math). Even if costs drop dramatically, you're looking at a huge maintenance expense when that comes up, as much or more than many ICE engine/transmission replacement items.
Even if you sell the car before battery replacement, it's going to hurt the resale value, much like a house with a bad roof at sale time.
Even if you sell the car before battery replacement, it's going to hurt the resale value, much like a house with a bad roof at sale time.
SByer
'08 #383
I don't because the subsidies are a sneeze in the wind compared to the subsidies for oil and coal. I'd rather they all be zero, but...
Updated the spreadsheet to include a lot of the feedback you guys gave me. Change log in first post.
I'm not sure if I calculated the degraded range correctly. If you get to 20% range degradation at 100,000 miles are you still drawing the (1) same amount of electricity (kWh) from your socket or (2) is the battery unable to hold as much electricity. I added calculations using the logic in (1).
I checked my electricity bill in a year time span and my rate + fees actually went down. I included a suggested % increase for electricity from a member here to be conservative. Gas rate increase was all over the map when I checked gasbuddy.com. Pretty interesting to see the evolution.
You'd really only need to think about replacing the battery when the range diminishes to the point that it no longer works for you. For me I'm going to get the 230mi range pack, which is overkill for my needs and ride it out until the range is less than 100mi or battery replacement is much cheaper. Remember that when Tesla is quoting End Of Life for the battery, they are talking about the battery being at around a 80% range level. IIRC the number they are giving us for their worst case scenario is getting to that 80% level at around 100,000mi.
Unfortunately, there isn't enough publicized data to determine if the degradation of range is linear or has some steep drop once it gets to a certain lifetime.
I'm not sure if I calculated the degraded range correctly. If you get to 20% range degradation at 100,000 miles are you still drawing the (1) same amount of electricity (kWh) from your socket or (2) is the battery unable to hold as much electricity. I added calculations using the logic in (1).
I checked my electricity bill in a year time span and my rate + fees actually went down. I included a suggested % increase for electricity from a member here to be conservative. Gas rate increase was all over the map when I checked gasbuddy.com. Pretty interesting to see the evolution.
You'd really only need to think about replacing the battery when the range diminishes to the point that it no longer works for you. For me I'm going to get the 230mi range pack, which is overkill for my needs and ride it out until the range is less than 100mi or battery replacement is much cheaper. Remember that when Tesla is quoting End Of Life for the battery, they are talking about the battery being at around a 80% range level. IIRC the number they are giving us for their worst case scenario is getting to that 80% level at around 100,000mi.
Unfortunately, there isn't enough publicized data to determine if the degradation of range is linear or has some steep drop once it gets to a certain lifetime.
KBF
Model X owner (formerly Cdn Signature Model S)
The battery's capacity decreases. It shouldn't make a difference as far as cost goes, as you will still have the same $$ per km.
I've read on this forum that Tesla engineers are thinking the range degrades at a high rate at first, levels out for a long time, then as it approaches end of life it has a downward curve (discussion here). Again, the only thing that affects is range, not cost to drive AFAIK. I haven't seen anything on the time it takes to get to something like 50% capacity.
I've read on this forum that Tesla engineers are thinking the range degrades at a high rate at first, levels out for a long time, then as it approaches end of life it has a downward curve (discussion here). Again, the only thing that affects is range, not cost to drive AFAIK. I haven't seen anything on the time it takes to get to something like 50% capacity.
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Todd Burch
14-Year Member
Tesla has often said that the Model S will have the same cost of ownership as a Ford Taurus, if the cost of gasoline is $4 a gallon.
Based on preliminary estimates, I'm having a hard time finding that believable unless you go out beyond 250k mi for the life of the car (at which price for fuel and maintenance exceeds the price of battery replacement.)
So far, I'm seeing cost of ownership approximately on par with a BMW 335i for the first 150k-200k mi. Wonder what Tesla was using for the total life of the car when they made that statement.
Based on preliminary estimates, I'm having a hard time finding that believable unless you go out beyond 250k mi for the life of the car (at which price for fuel and maintenance exceeds the price of battery replacement.)
So far, I'm seeing cost of ownership approximately on par with a BMW 335i for the first 150k-200k mi. Wonder what Tesla was using for the total life of the car when they made that statement.
@KBF: If the batteries ability to hold energy decreases, can you assume that the new energy level decrease will be directly proportional to the range decrease? I would have thought $ per distance would be impacted a bit over time somehow. Maybe it turns out to be negligible. For now I'll just zero out the range decrease setting in my v2 comparison spreadsheet.
@Todd Burch:
Here's the quote you're referring to ...
Based on the above statement, for all we know Tesla could have used an average gas cost of $8 over ownership of 200,000miles. That paragraph was worded with wiggle room on purpose. Typical company jargon.
If you use my v2 spreadsheet, change the Tesla to the 160mi config (42 kW·h battery capacity) and zero out the 10k cost of the 230mi pack, bump the car1 cost to 35000, zero out the gas & electricity increase, and zero out the EV range decrease number, change the mpg to 22, and set the miles for comparison to 100,000miles, the Tesla Model S is about the same cost of ownership as the Ford Taurus. Bump up the gas cost from $4 to $4.10 and the Tesla is cheaper. My spreadsheet is on the cheaper end for the ICE car maintenance too since I do a bunch of my own service on an ICE car.
Tesla's press release doesn't seem too far off the mark.
@Todd Burch:
Here's the quote you're referring to ...
Above referenced from Autoblog
Based on the above statement, for all we know Tesla could have used an average gas cost of $8 over ownership of 200,000miles. That paragraph was worded with wiggle room on purpose. Typical company jargon.
If you use my v2 spreadsheet, change the Tesla to the 160mi config (42 kW·h battery capacity) and zero out the 10k cost of the 230mi pack, bump the car1 cost to 35000, zero out the gas & electricity increase, and zero out the EV range decrease number, change the mpg to 22, and set the miles for comparison to 100,000miles, the Tesla Model S is about the same cost of ownership as the Ford Taurus. Bump up the gas cost from $4 to $4.10 and the Tesla is cheaper. My spreadsheet is on the cheaper end for the ICE car maintenance too since I do a bunch of my own service on an ICE car.
Tesla's press release doesn't seem too far off the mark.
JRP3
Hyperactive Member
I don't know what Tesla does in their Roadster "tune up" but unless there is something malfunctioning there should be nothing to "tune", and if something is malfunctioning it should be under warranty. The idea of a yearly tune up is left over from the ICE age, and even modern ICE's don't really require such, other than oil changes.
This is a very helpful spreadsheet - nice work!
One thing that would be interesting to factor in is the replacement cost of a battery pack at x number of miles. So for example, if you entered of the battery pack cost and mileage for replacement, you could presumably amortize that cost over the life of the car or factor in the replacement purchase or something similar.
Another thing that pops to mind is a way to factor in depreciation. I'm not sure how best to do this, but it's probably an important factor in true TCO. Even if the depreciation factor was a pure guess (which would likely be the case - at least early on), it would give a way to do "what-if" scenarios.
Thoughts?
One thing that would be interesting to factor in is the replacement cost of a battery pack at x number of miles. So for example, if you entered of the battery pack cost and mileage for replacement, you could presumably amortize that cost over the life of the car or factor in the replacement purchase or something similar.
Another thing that pops to mind is a way to factor in depreciation. I'm not sure how best to do this, but it's probably an important factor in true TCO. Even if the depreciation factor was a pure guess (which would likely be the case - at least early on), it would give a way to do "what-if" scenarios.
Thoughts?
The issue of predicting battery replacement and depreciation in a spreadsheet like this is pretty tricky.
Battery replacements can fall under 2 main categories IMO; total battery replacement or partial battery replacement. Both battery replacements would only take effect after the battery warranty runs out. Both replacements would be completely different in cost. Unfortunately, we don't have any idea on how much either approach would cost and at what mileage/time. There aren't enough cars on the road to get good statistics on how long li-ion batteries, of the kind Tesla uses, last in a pure electric car.
The spreadsheet also only really includes preventative maintenance items for both the ICE and EV. To include battery replacement for the EV it would only be fair to include engine (including manifold, intake, fuel injectors, etc), transmission, and full exhaust (including catalytic converter, muffler, etc) replacement in the ICE. I'd also need to add electric motor replacement for the EV. My assumption for the comparison is that no critical failures occur for the specified time of comparison.
To properly do depreciation justice I'd have to pull in a database of data like the folks at Edmunds and that's above my Excel spreadsheet-only expertise. I'd have to link it with Access or convert the sheet into a format for a server and use mysql or something. Teslanomics included depreciation but they used the 1st gen Rav EV and I don't fully agree with that.
I was trying to keep this spreadsheet macro/database free. The INDIRECT function command in Excel is pretty nice. New one I learned doing this.
I'm probably just over thinking the problem or my brain is actively making excuses because the suggestions seem hard to implement. :smile:
I might take a stab later at allowing the user to configure a polynomial to calculate depreciation for each car based on what ever data is available.
Thanks for the feedback and trying the sheet out.
Battery replacements can fall under 2 main categories IMO; total battery replacement or partial battery replacement. Both battery replacements would only take effect after the battery warranty runs out. Both replacements would be completely different in cost. Unfortunately, we don't have any idea on how much either approach would cost and at what mileage/time. There aren't enough cars on the road to get good statistics on how long li-ion batteries, of the kind Tesla uses, last in a pure electric car.
The spreadsheet also only really includes preventative maintenance items for both the ICE and EV. To include battery replacement for the EV it would only be fair to include engine (including manifold, intake, fuel injectors, etc), transmission, and full exhaust (including catalytic converter, muffler, etc) replacement in the ICE. I'd also need to add electric motor replacement for the EV. My assumption for the comparison is that no critical failures occur for the specified time of comparison.
To properly do depreciation justice I'd have to pull in a database of data like the folks at Edmunds and that's above my Excel spreadsheet-only expertise. I'd have to link it with Access or convert the sheet into a format for a server and use mysql or something. Teslanomics included depreciation but they used the 1st gen Rav EV and I don't fully agree with that.
I was trying to keep this spreadsheet macro/database free. The INDIRECT function command in Excel is pretty nice. New one I learned doing this.
I'm probably just over thinking the problem or my brain is actively making excuses because the suggestions seem hard to implement. :smile:
I might take a stab later at allowing the user to configure a polynomial to calculate depreciation for each car based on what ever data is available.
Thanks for the feedback and trying the sheet out.
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JRP3
Hyperactive Member
There should be no need to add electric motor replacement for an EV. There is a single moving part supported by two bearings, it should outlast the vehicle. Replace the two bearings if needed and it should be ready to outlast another vehicle.
Todd Burch
14-Year Member
That's right. Somewhere I read that the Model S motor will comfortably exceed 1 million miles before needing replacement.
