EV Savings after 2.5 years and 44,000 miles

[whttiger25]

Hey all,

I wanted to share a screen shot of a spreadsheet I built to track the true cost of my Model S. My goal was to quantify the statement "electric cars are cheaper to run, thus you can afford to pay more for one than a comparable gas car". At the time I bought the car, given how much I drove, how often I crossed the bay bridge (which at the time offered a $3.5 rush hour discount for EV drivers, now it's $4), and assuming a 25MPG for the comparable gas car I would have driven, I estimated I'd save $194 a month. It's turned out to be $218 so far.

As you can see, I update the current gas price each month, along with my mileage. The amount I spend on electricity also varies a bunch, as I have free supercharging so very often I pay zero when I can make it to local superchargers.

Lastly, I track the average true monthly cost since I owned the car, the monthly depreciation (I use KBB to estimate), and the average monthly pure $ cost, not including savings related to EV driving. The goal here is to keep the car long enough so that this number (the average monthly true cost) looks reasonable. Currently it's about $1200 a month. I'm hoping to keep the car 15 years, by then this number will be much much lower.



I purchased the car in June of 2017 and have saved nearly $6500 so far.

 

[Ostrichsak]

My estimates based on our gas/electricity costs prior to ever buying a Tesla was that we'd save ~$2,500 per year in fuel savings alone.

So far, after over a year of ownership we're saving about that amount per vehicle per year. It sounds like your savings line up with my previous estimates and current real-world experience as well.

Granted, we're not factoring in repair costs and EV should also save money here compared to all of the failure points on an ICE vehicle but I'm satisfied with our savings on fuel prices alone.

Not to mention that we no longer own anything that uses gas or oil so the bigger picture take is that we're no longer adding to the dependence on foreign entities for such things. 100% of our energy needs are created domestically now... locally for the most part. That's another bonus to the thousands (about $5k per year for us on two cars) of dollars we're saving.

The way I see it, our purchase price is lowered about $2,500 per car per year that we own it based on fuel savings. Our last vehicles we owned for 8 years and I assume that these EVs will go even longer. Extrapolating these numbers out of over ten years (for round math) we're looking at about $25k per car that we saved on fuel alone.. not taking into account things like oil changes or other maintenance which helps that figure even more. That means that if you buy a $50k Tesla you should see about half of that back in savings as you approach ten years of ownership. Even sooner if you factor in oil changes and other repairs & maintenance. Pretty cool IMO.

One thing that helps with your total number is to not buy new so you don't take such a loss in terms of depreciation. Also, if you're in a position to pay cash you have no interest to a bank to factor in either. These two alone are massively huge in terms of total cost of ownership over 10-15 years.

In my rambling above I base my figures off of total purchase price. This way I'm not trying to track several figures side by side and instead have a static target. If I sell/trade the car prior to the time that I recoup my costs via savings I can then deduct that sale price or amount from whatever "balance" remains if that makes sense.

Either way, love seeing this stuff because this is the real-world cost of ownership that affects individual owners more than the BS the anti-Tesla community continually tries to get us to focus on. It's what makes the #'s make sense to someone like me who is worried most about total cost of items and being as frugal (even when splurging on something like a Tesla) as possible.

 

[whttiger25]

One thing that helps with your total number is to not buy new so you don't take such a loss in terms of depreciation. Also, if you're in a position to pay cash you have no interest to a bank to factor in either. These two alone are massively huge in terms of total cost of ownership over 10-15 years.

We still had the full $7500 federal rebate available when I purchased my car. Also, the 100D battery was new, and thus there was no realistic used market for it. I wanted hte margin of error in terms of range after future degradation the 100D woudl provide. My previous vehicle (which had just been totalled) was a 90D, and the degradation on that in just 20,000 miles had been concerning.

Now, the used market is much more robust than it was just 2.5 years ago, and with the loss of the federal rebate I do agree with you. Tesla has also drastically lowered prices so that's another factor. My car was $98,700 and would probably be about $80k now new. It's not apples to apples, i got the cloth interior, and no air suspension, basic audio, which are now all upgraded in the base model. So I'm feeling a bit more depreciation than a new car buyer now would.

 

[OrbiterTI4]

...
Lastly, I track the average true monthly cost since I owned the car
...

What goes into this number? I'm assuming loan payment and the electric/tolls you've already shown, but anything extra? Insurance? Repairs? Registration?

If I went back to try and calculate what an ICE would have cost over the same 4.5 years I've had an S, my expectation would be the actual repair costs on the S will have already negated the fuel savings (and if I do the $1000 instrument cluster repair now that mine is bubbling/leaking, will further negate the next few years).

 

[whttiger25]

What goes into this number? I'm assuming loan payment and the electric/tolls you've already shown, but anything extra? Insurance? Repairs? Registration?

If I went back to try and calculate what an ICE would have cost over the same 4.5 years I've had an S, my expectation would be the actual repair costs on the S will have already negated the fuel savings (and if I do the $1000 instrument cluster repair now that mine is bubbling/leaking, will further negate the next few years).

Registration and Insurance are marginally higher, yes, but my repairs and service have been lower than my previous gasoline cars. I so far consider it a wash. All my repairs have been in warranty. We shall see as I emerge from warranty next year....

Also, I took out a 1.49% 72 month loan for the vehicle, and decided to pay it off early in April of this year, so the financing costs, while included, are minimal. Probably should have kept the debt at that rate and invested in the S&P, but I don't really like debt.

 

[Zooomer]

I don't see any fuel savings in winter and it's pretty small in summer. 500w/h winter, .18 for a KW in summer.

 

[mspohr]

My quick back of envelope savings for my almost 5 year old Model S is about $20,000 in 85,000 miles. This includes gas savings and maintenance (no oil changes, lube, filters... and whatever else dealers do to generate revenue).
(Actually, savings are really more since I don't pay for electricity. It's free from solar PV at home or free Supercharging on the road.)

 

[Ostrichsak]

I don't see any fuel savings in winter and it's pretty small in summer. 500w/h winter, .18 for a KW in summer.

Based on ???? Lower efficiency of EVs in the winter?

I tracked my MPG with every tank across several vehicles (dozens) across a couple of decades prior to owning EVs. I'm located on the Front Range of the Rocky Mountains of Colorado. I consistently saw decreases in fuel efficiency in the 15-20% range... this figure increased as more and more gas stations increased the amount of ethanol they put in the fuel. Summary: machinery HATES the bitter cold and it doesn't matter if it's ICE or EV & whenever you put a human in them that prefers the warmth this becomes magnified.

In fact, where I live, the cost of electricity actually goes down in the winter months but about 20% which MORE than makes up for any difference in efficiencies between ICE and EV tech. For me, I pay roughly 1/10th per month to "fuel" my EV than I paid in gas prices to fuel my ICE vehicles. The differences between winter/summer rates in electricity and gas efficiency differences between summer and winter when making the comparison is nominal. This is a direct comparison of my wife's Model S to her ICE car and my Model S to my ICE pickup.

tl;dr the difference between ICE and EV in the winter is nominal at best. It's a non-issue if you actually compare apples to apples.

 

[mspohr]

I don't see any fuel savings in winter and it's pretty small in summer. 500w/h winter, .18 for a KW in summer.

Gas at $3.00/gal = $0.15/mile (Large sedan 20 m/gal)
So, your electricity costs $0.30 kWh in winter?

 

[OrbiterTI4]

You inspired me to dig through my records. What I found with a quick search of my Quicken records...

Pre-Tesla: 09 Chevy Malibu, 6.5 years of ownership, $1802.88 in oil changes / flushes / filters / batteries / tires.
2015 Model S: 4.5 years of ownership, $3056.51 in ski tape / door handles / first+second annual service / ac desiccant / filters / tires.

Granted some of this is on a sliding scale (my Malibu tires were closer to needing replacement than new when I sold, did I need to do the annual services in 2016 and 17 before Tesla changed schedules, etc.) but looks like I'm on the losing side of the bell curve.

Next project will be to look up wife's car (Rav4) and see how it compares...and figure out fuel savings, if I can.

Tangential question - for people calculating fuel savings, did you include the cost of electrical modifications to your home in the equation? In my case, I've modified two homes to add in a subpanel...

 

[mspohr]

You inspired me to dig through my records. What I found with a quick search of my Quicken records...

Pre-Tesla: 09 Chevy Malibu, 6.5 years of ownership, $1802.88 in oil changes / flushes / filters / batteries / tires.
2015 Model S: 4.5 years of ownership, $3056.51 in ski tape / door handles / first+second annual service / ac desiccant / filters / tires.

Granted some of this is on a sliding scale (my Malibu tires were closer to needing replacement than new when I sold, did I need to do the annual services in 2016 and 17 before Tesla changed schedules, etc.) but looks like I'm on the losing side of the bell curve.

Next project will be to look up wife's car (Rav4) and see how it compares...and figure out fuel savings, if I can.

Tangential question - for people calculating fuel savings, did you include the cost of electrical modifications to your home in the equation? In my case, I've modified two homes to add in a subpanel...

I built a new garage so the electrical cost was minimal.

(What's ski tape? Also, probably didn't need those two annual services.)

 

[Ostrichsak]

Tangential question - for people calculating fuel savings, did you include the cost of electrical modifications to your home in the equation? In my case, I've modified two homes to add in a subpanel...

I added only $39 worth of parts from Home Depot to my charging solution which is a NEMA 14-50. I was an electrician many years ago for a very brief stint. In our case, we're fortunate enough that our panel is on the wall of our garage right where we'd want to install connectors. I even bought two signature HPWC and they're still sitting in the box because we just haven't needed them. Sure, I could have thrown thousands of dollars at this solution but it just wasn't necessary. Others may not be as necessary but if you plan properly and shop around it's a lot less expensive than most think. Paying an electrician to install a NEMA 14-50 should be relatively inexpensive (probably starting around $300 depending on where you live) unless your panel is on the other side of the house the parts cost can add to that price dramatically. A NEMA 14-50 is MORE than enough for these cars and what Tesla even recommends.

 

[OrbiterTI4]

I built a new garage so the electrical cost was minimal.

(What's ski tape? Also, probably didn't need those two annual services.)

Did you build the garage specifically for getting a Tesla, or was the garage being built anyway, so adding a 14-50 was no big deal?

The ski tape came about at my first annual service - apparently its a barrier surrounding the battery pack (but inside of the debris shield/cover) - apparently a rock or something had worked its way inside and damaged the protective tape around the HV battery.

...
Paying an electrician to install a NEMA 14-50 should be relatively inexpensive (probably starting around $300 depending on where you live) unless your panel is on the other side of the house the parts cost can add to that price dramatically. A NEMA 14-50 is MORE than enough for these cars and what Tesla even recommends.

Yeah, we've had the opposite luck - the main boxes have been located as far away from the garage as physically possible, so it required running 50' of wire in each house to the subpanel installed in the garage (in one case, trenching and then conduit through the backyard) along with replacing a main breaker in the second home, since it was only 100A main service for the existing 2 ACs (40A each) and 2 electric ovens (30A each) and 30A dryer, let alone the NEMA 14-50 going in! (We actually made the subpanel 100A, with 2x 14-50 and a 6-50 in case I got crazy and wanted to weld). I think the combined electrician bills for the two homes was $6500.

Ditto on 14-50 being sufficient though. I can remember on one hand the number of times I arrived home late enough with too low a charge that I wasn't able to get to 90% before leaving again in the morning.

 

[mspohr]

Did you build the garage specifically for getting a Tesla, or was the garage being built anyway, so adding a 14-50 was no big deal?

Well... that's a long story.
We had been living without a garage at this house for about 15 years. Several times we had considered building one but didn't. After ordering the Tesla, we decided we needed a garage and of course we ended up building a detached large two car garage plus a loft extra bedroom above. It ended up being quite expensive but we rent the bedroom on AirBnB which provides a nice income and will pay for the garage over time.
So, yes, we built the garage for the Tesla but I didn't think it should be counted as a Tesla expense. It cost much more than the Tesla.

 

[whttiger25]

So for me, I lived in a Condo, I paid $3000 to install an Evercharge unit, but have since sold hte condo. I never really considered it a cost per se because It was a capital improvement that I would in theory get back whenever selling the condo, considering an EV charger in my complex was fairly rare. I did sell the condo and who knows maybe I sold it for $3k more?

Now I'm renting, and totally dependent on 110V charging at work, and occasional local supercharging. The new Supercharger in Walnut Creek (where I work) has made this very convenient indeed. However for me this means that electricity is 99% free, I only pay in certain rare situations. I'm aware that won't be possible for a lot of people, or a lot of people will choose to pay for convenience of charging in their home. If I owned a home, I'd probably charge there more When I owned the condo and the Evercharge unit, I did pay more for electricity due to its convenience (including the $15/mo subscription fee which included the mandatory liability insurance).

When I do eventually buy a house, proximity of the electrical panel in garage will be a consideration, but I also continue to believe modernizing a home to be EV charging capable is a capital investment in the house and not really on par with an "expense" of owning an EV. At the very least it is certainly something I'd include in the basis cost of the house for tax purposes.