Determine Cost Per Mile?

[JeffK]

I'm afraid that any focus on cost of electricity per mile is wildly misplaced, certainly for the first few years of ownership, because it is mere rounding error in the total cost of ownership.

While sales tax, insurance, vehicle license tax, etc. can be significant, by far the largest component of cost of ownership is depreciation. Look around this site and see folks trying to sell low mileage P90DLs for tens of thousands of dollars less than they paid, often more than $5 cost per mile in depreciation alone!

Can you please do a comparison against a Lamborghini? Make sure to add in the $2000 oil changes and $4000 spark plugs. How much per miles is it? Costs over the course of a year, two years, ten years?

Maybe you're right, maybe owning an EV is just too expensive in the long run.

 

[SageBrush]

I'm afraid that any focus on cost of electricity per mile is wildly misplaced, certainly for the first few years of ownership, because it is mere rounding error in the total cost of ownership.
While sales tax, insurance, vehicle license tax, etc. can be significant, by far the largest component of cost of ownership is depreciation. Look around this site and see folks trying to sell low mileage P90DLs for tens of thousands of dollars less than they paid, often more than $5 cost per mile in depreciation alone!

I was with you until the $5/mile depreciation remark. I've been tracking used Tesla prices for over a year now and $1/mile is pretty typical once the tax credit is removed from the calculation.

That is pretty exorbitant for a Honda/Toyota owner like me, so no need to mix in hyperbole.

 

[insaneoctane]

@wrf2e
I must be doing different math than @Haxster and others, because I see EV as a big win.
I used:

• 0.281 kWh/mi = 3.56 mi/kWh
• $0.065 / kWh (I have solar and net metering)
• 26 MPG ICE comparison (Nissan Altima)
• $3.50/gal (S.California)
• 20,000 mi / year (I drive a lot)

ICE fuel calc:

(20,000 mi/yr) / (26 mi/gal) = 769 gal / yr
(769 gal/yr) x ($3.50/gal) = $2,692 / yr
​

EV fuel calc:

(20,000 mi/yr) / (3.56 mi/kWh) = 5,620 kWh / yr
(5,620 kWh/yr) x ($0.065/kWh) = $365 / yr​

So, every year I drive the Model 3 vs ICE I save $2,327 ($2,692 / yr - $365 / yr). After 5 years that's $11,635 and after 10 years that's $23,270. Combined with a federal tax credit of $7,500 and a state rebate of $2,500 my calculations show that only considering fuel and incentives that driving an EV for 10 years vs ICE saves me $33,270.

As I've said in other threads, rather than putting that savings in my pocket (which was my original plan), I'm just spending more on my model 3 than I planned and choosing LR, PUP, AP etc. So while if I picked the super base M3 I could claim these savings, instead I'm just giving them back to Tesla in exchange for an amazing car...well played Tesla!

PS- If someone can find an issue with my math, please let me know.

 

[SageBrush]

@wrf2e
I must be doing different math than @Haxster and others, because I see EV as a big win.
I used:

• 0.281 kWh/mi = 3.56 mi/kWh
• $0.065 / kWh (I have solar and net metering)

If you want nits picks ...
Are all your miles fueled from home ?


---
My numbers work out differently than yours because I drive half the amount and compare to a Prius Prime that averages 100 mpg with much cheaper petrol. This is true even though I also have PV at less than half your cost.

ICE fuel calc:
(10,000 mi/yr) / (100 mi/gal) = 100 gal / yr
(100 gal/yr) x ($2.2/gal) = $220 / yr

EV fuel calc:
(10,000 mi/yr) / (4.5 mi/kWh) = 2,200 kWh / yr
(2,200 kWh/yr) x ($0.025/kWh) = $55 / yr

Annual savings: $165 a year

 

[JeffK]

If you want nits picks ...
Are all your miles fueled from home ?


---
My numbers work out differently than yours because I drive half the amount and compare to a Prius Prime that averages 100 mpg with much cheaper petrol. This is true even though I also have PV at less than half your cost.

ICE fuel calc:
(10,000 mi/yr) / (100 mi/gal) = 100 gal / yr
(100 gal/yr) x ($2.2/gal) = $220 / yr

EV fuel calc:
(10,000 mi/yr) / (4.5 mi/kWh) = 2,200 kWh / yr
(2,200 kWh/yr) x ($0.025/kWh) = $55 / yr

Annual savings: $165 a year

Wait, did you just mention a PHEV and not account for electricity costs? Prius prime gets 54 mpg on gas alone.

 

[SageBrush]

Wait, did you just mention a PHEV and not account for electricity costs? Prius prime gets 54 mpg on gas alone.

Good catch, but on purpose.
I consume 6.3*130 kWh a year, at 2.5 cents a kWh

I was too lazy to include it because it is such a small amount
And I figured people hoping to show the EV cost advantage would overlook the detail

 

[JeffK]

Good catch, but on purpose.
I consume 6.3*130 kWh a year, at 2.5 cents a kWh

I was too lazy to include it because it is such a small amount
And I figured people hoping to show the EV cost advantage would overlook the detail

Anything I can do to increase that cost advantage to quiet the naysayers

 

[Topher]

People always cite the rates they pay but don't include the installation cost and any fixed costs to the utility company.

People, not ME. I pay $0.083 per kWh which INCLUDES installation cost, fixed payment to the utility ($12.88 / month). On the other hand it does NOT include any payments I get from selling RECs (since I haven't gotten a check yet). Residential rates in the area are $0.158 to $0.164 depending on usage etc.

By the way, what are they citing if not installation costs? Actual panel costs are less than 20% of the total.

Thank you kindly.

 

[JeffK]

People, not ME. I pay $0.083 per kWh which INCLUDES installation cost, fixed payment to the utility ($12.88 / month). On the other hand it does NOT include any payments I get from selling RECs (since I haven't gotten a check yet). Residential rates in the area are $0.158 to $0.164 depending on usage etc.

By the way, what are they citing if not installation costs? Actual panel costs are less than 20% of the total.

Thank you kindly.

Likely they are citing what they are usage / monthly utility bill.

Let's say a system is $1.50/ watt and you get a 10 kW system that's around $10k after 30% tax incentives. Over the course of 20 years, assuming you paid outright with no interest, that's $41.67 per month add in fixed costs, we can use yours as an example, and you are up to $54.55 per month before factoring in night usage. Let's say you want storage. Powerwall adds around $29 per month after cost of installation over 20 years so you're up to $83.55 per month. This is lower if you state law makes the utility company pay you in cash instead of giving credits. Some places are even trying to do away with net metering.

My average bill on the grid alone is under $75 / month ($30-40 in the winter and a little over $100 in the summer.).

Right now, for me, unless my usage skyrockets or the price of solar comes down, it doesn't make financial sense. After I get a Model 3, I'll have to run the math again based on my usage. It might make financial sense right away with an EV.

 

[Topher]

before factoring in night usage.

What is this night usage you speak of? Net metering means the difference between what you export and what you import. Properly sized, this should be zero over the course of a year.

Let's say you want storage.

Why would you want storage? It isn't required for solar. If you get frequent or long power outages you might want to consider storage, otherwise, it is a waste of money. Or if your utility bribes its way into repealing net-metering, then you go off-grid, but that is a separate calculation, and you cut out the monthly minimum (which for you looks to be about $10).

So, you are paying $75 when you could be paying $55 per month. Or $4,800 in savings over the course of 20 years. And that isn't counting any increases in the price of electricity.

Yes, wait until you know what you will be using for your EV before committing to a size for the solar system.

Thank you kindly.

 

[ArizonaP85]

I was with you until the $5/mile depreciation remark. I've been tracking used Tesla prices for over a year now and $1/mile is pretty typical once the tax credit is removed from the calculation.

That is pretty exorbitant for a Honda/Toyota owner like me, so no need to mix in hyperbole.

Please look at posts throughout the Teslas for Sale section of this site:

2016 S 90 D Sticker $111,200 Fully Loaded Ask $75,000 9,500 miles

$111,200 - $7500 = $103,700 original net cost

$103,700 - $75,000 = $28,700 depreciation

$28,700 / 9500 miles = $3.02 per mile AND THIS IS NOT A LUDICROUS MODEL! You'll see that as I cited, those have even worse depreciation.

How about this one?

For Sale: 2016 Model S P90DL (Refresh) [5800 miles]

$142,700 original cost, asking $102,000

$40,700 - $7500 tax credit = $33,200 net depreciation

$33,200 / 5800 miles = $5.72 per mile IF HE GETS HIS ASKING PRICE!

I am NOT trying to disparage Teslas in ANY way, merely pointing out that focusing on two, five or even ten cents electricity cost per mile is misplaced. IF you purchase a discounted CPO car and/or are able to amortize your initial purchase cost over many years and 100,000+ miles, then electricity cost per mile might be more relevant. However, as I pointed out originally, none of us is guaranteed protection against a "forced" sale through totaling of our cars at a much higher rate than other cars for similar accidents, so the risk of not being able to amortize cost over a long term is always present.

To the other comment about Lamborghini operating costs: I don't personally know any Lamborghini owners but I doubt operating costs factor into their decision to purchase and drive a half-million dollar Aventador or even a $200+K Huracan. Certainly they are not trying to split hairs between two and five cents per mile additional operating cost.

Drive and love your Tesla, but please don't base your purchase decision solely on electricity cost per mile while ignoring the many other, higher, components of operating costs.

 

[JeffK]

Please look at posts throughout the Teslas for Sale section of this site:

2016 S 90 D Sticker $111,200 Fully Loaded Ask $75,000 9,500 miles

$111,200 - $7500 = $103,700 original net cost

$103,700 - $75,000 = $28,700 depreciation

$28,700 / 9500 miles = $3.02 per mile AND THIS IS NOT A LUDICROUS MODEL! You'll see that as I cited, those have even worse depreciation.

How about this one?

For Sale: 2016 Model S P90DL (Refresh) [5800 miles]

$142,700 original cost, asking $102,000

$40,700 - $7500 tax credit = $33,200 net depreciation

$33,200 / 5800 miles = $5.72 per mile IF HE GETS HIS ASKING PRICE!

I am NOT trying to disparage Teslas in ANY way, merely pointing out that focusing on two, five or even ten cents electricity cost per mile is misplaced. IF you purchase a discounted CPO car and/or are able to amortize your initial purchase cost over many years and 100,000+ miles, then electricity cost per mile might be more relevant. However, as I pointed out originally, none of us is guaranteed protection against a "forced" sale through totaling of our cars at a much higher rate than other cars for similar accidents, so the risk of not being able to amortize cost over a long term is always present.

To the other comment about Lamborghini operating costs: I don't personally know any Lamborghini owners but I doubt operating costs factor into their decision to purchase and drive a half-million dollar Aventador or even a $200+K Huracan. Certainly they are not trying to split hairs between two and five cents per mile additional operating cost.

Drive and love your Tesla, but please don't base your purchase decision solely on electricity cost per mile while ignoring the many other, higher, components of operating costs.

Again your numbers mean nothing as depreciation is still lower than with a comparable ICE.

Example a 2016 Aston Martin Rapide S @ 2,901 miles with a 0-60 in 4.2 seconds like the 90D.

MSRP was $206,000 asking price is $149,520 so that's a depreciation of $56,480
$56,480 / 2901 = $19.47 / mi

Compared to the ICE, the EVs are a steal (oh and cheaper to run per mile).

Plus, who wants all these buttons??

 

[SageBrush]

Please look at posts throughout the Teslas for Sale section of this site:

I think you found some outliers, and they are probably explained by some combination of the following:

1. Cars are less than a year old
2. No AP2 ?

Look at cars that are 3-5 years old

 

[obe1]

One thing this calculation is missing. The vampire loss. When I installed a PV system I calculated the lose due to constantly charging the battery. This amount will depend on settings, ie always awake ect....

Since you are calculating the cost per mile. This cost could be high if you drive very little miles a year, or not much if you drive a lot. changing the cost per mile. For example if you only drive one mile in a year then the vampire cost of the whole year gets added to the 3 cents. Making that an expensive mile. Of course extreme but you get the idea.

If the efficiency is the rumored 0.237 kWh / mi which it's likely true, then it's your price / kWh * 0.237.

My current house it's 10 cents always, so $0.10 / kWh * 0.237 kWh / mi = $0.0237 ... so if you were to round up and include some charging losses it's a little less than 3 cents per mile.

My prius, for comparison, gets 44 mpg and gas is recently $2.25 so $2.25 per gallon / 44 mpg = $0.051 so compared to a prius, the Model 3 would cost about half as much per mile.

 

[insaneoctane]

If you want nits picks ...
Are all your miles fueled from home ?

I'm expecting so. My home price per kWh is pretty amazing around here. Work is not free, nor will SC, so home for almost all except trips that require SC.

ICE fuel calc:
(10,000 mi/yr) / (100 mi/gal) = 100 gal / yr
(100 gal/yr) x ($2.2/gal) = $220 / yr

EV fuel calc:
(10,000 mi/yr) / (4.5 mi/kWh) = 2,200 kWh / yr
(2,200 kWh/yr) x ($0.025/kWh) = $55 / yr

Annual savings: $165 a year

Your Prius is already in EV territory with 100 MPG. Heck I think almost all Tesla's (prior to M3) are < 100 eMPG and therefore wouldn't expect to gain much.
Wow. I pay a lot for EVERYTHING compared to you. I knew Southern California was high cost of living, but damn!