Real-world comparison of my cost per mile - MS versus ICE

[PatD]

So I finally got my energy monitoring system up and running. Had a very short errand to run today, probably didn't get above 35 miles per hour. Drove 3.6 miles.

My MS was already full when I left. When I got home, plugged her back in. My monitoring system showed just about 40 amps was being drawn. Didn't take long to charge; checked my monitoring and it showed I just used $.33 of electric (Our rate is $.14/kwh for anyone interested.)

Did the math and I used $.09/mile with the Tesla.

In my old TL, assuming $3.50/gallon for gas (I only used premium, as it suggested - shoot me) and assuming 22 miles per gallon (Probably high for the errand I ran, but 22 was a good overall average for me), that same trip would have cost me $.57/mile.

Wow. Just wow. Can't wait to do a longer trip to see what the numbers look like - I'll report back!

Also, if anyone is interested, I installed a Green Eye Monitor from Brultech (http://www.brultech.com/home/store/product.php?id_product=114) Very simply to install, runs over my wireless network. Can monitor all sorts of stuff. It, out of the box, doesn't really give you stats. You either buy their Dashbox, or tie it in to Smart Energy Groups (https://smartenergygroups.com), which is what I did. Here's a view of my garage sub-panel, which ONLY has the Tesla on it so far. I built this dashboard and can view it from anywhere and add different stats and such. I only spent a minute or two on it, so it's not necessarily the final view, but until I get some data in to it. . .

https://smartenergygroups.com/widgets/1c46e9d6670aa5d617bdb60d62eb10d7acd9abdb

 

[lphe]

$0.33 of electricity divided by $0.14/kWh = 2.36 kWh. Did charging really require 2.36 kWh of electricity? 2.36 kWh / 3.6 = 0.655 kWh / mi. That seems rather high. You will need to monitor the total miles driven and the total electricity consumed over a much longer period of time to get a better estimate of the cost per mile. You will probably find the cost to be even lower than you observed above.

But isn't $3.50/gallon / 22 miles / gallon = $0.16 / mile?

 

[Candleflame]

thank god in europe there is a highly useable metric system and petrol gets sold by the litre. X_x

So if you are crusing and it shows ~200 Watts/kilometer you just need to mentally remove the last 0 to get the consumtion in kw/100km which allows comparison directly with litre/ 100km.

So in that case 20kw/100km as compared to perhaps 7L/100km for an ICE car. 20kw are about 5.50 euros in Germany at daytime and 7L about 9 euros.

Just use metric, you know it makes sense!

 

[green1]

thank god in europe there is a highly useable metric system and petrol gets sold by the litre. X_x

And yet the UK still hasn't figured it out, so they drive by the mile and fill by the litre (which must make for some interesting mileage calculations!), at least the Americans are consistent in their ignorance of the metric system.

(not that I can talk really, we Canadians may officially be metric, but I know my height and weight in imperial, but the size and weight of my groceries in metric, go figure!)

 

[PatD]

You're right on the fuel cost. That was total fuel usage, not per mile. Damn. Doesn't look as good now! I'm sure longer trips will yield more interesting results.

Take a look at the last link in my original post. That's my usage for the trip in question. I thought it high too but...

 

[green1]

You're right on the fuel cost. That was total fuel usage, not per mile. Damn. Doesn't look as good now! I'm sure longer trips will yield more interesting results.

Take a look at the last link in my original post. That's my usage for the trip in question. I thought it high too but...

Really your data point is too small to get any real idea of it. In total I'd expect about 10% higher than the car's consumption during the trips. (barring any preconditioning)

 

[Candleflame]

And yet the UK still hasn't figured it out, so they drive by the mile and fill by the litre (which must make for some interesting mileage calculations!), at least the Americans are consistent in their ignorance of the metric system.

(not that I can talk really, we Canadians may officially be metric, but I know my height and weight in imperial, but the size and weight of my groceries in metric, go figure!)

I'm not british and think in metric. In fact, I've been here for so long when I see something in miles my brain has already erased it and replaced it with kilometers. Like when I see a speed limit 50 sign I just see 80. :biggrin:

 

[majorlance]

Based on my experience, the Tesla uses much more energy in the initial mile or so than it does afterwards. A short trip here or there won't be as efficient as longer trips... and I mean around town, not out on the road. On road trips, it's much better.

My 130 mile trip to the Delaware costs about $4.50 to $5.00 of electricity (@.133 per kwh). My previous 2013 MB S550 would use around 6 gallons of premium... $20 - $25 depending on the price of premium. Around town, I see about the same ratio meaning it costs about 20% of my prior ICE car.

Mother's Day weekend I'm traveling up to Boston from DC and back (about 470 miles)... my cost will be.... hmmm. $0! A couple of supercharger stops plus charging at my sister-in-laws. Which is nice!

 

[HankLloydRight]

Because so few people know their actual $/mile cost to drive their cars, I calculated a comparative $/gallon cost to drive my MS versus my 2002 BMW M5.

This was back when the cost of fuel was >$3.50/gallon for premium, but my adjusted $/gallon to drive the MS (compared to the M5) was $0.37/gallon. That's a number people can relate to.

*I was also factoring in that my cost for electricity is $0.066/kWh due to Solarcity power lease.

 

[brucet999]

Mother's Day weekend I'm traveling up to Boston from DC and back (about 470 miles)... my cost will be.... hmmm. $0! A couple of supercharger stops plus charging at my sister-in-laws. Which is nice!

Will your in-laws still want you to visit after they figure out why their electric bill is so high, or is that part of your strategy?

 

[CHG-ON]

So... Regardless of all the very complicated calcs needed to really see how much energy is used to charge the MS; which is way beyond my simple mind. Here is what I have experienced:

I changed to the California PGE EV rate plan and my total cost for electricity DROPPED 100/mth when I bought the car. Now, there are some variables here. When I bought my girl I was driving at a cost of 650/mth for gas for an Acura RDX Turbo that got a measly 18 mpg. That was a rate of 30/yr. Then I quit my miserable job. During that time (2 months) I saw a 100/mth increase in my electricity cost. So I was saving 550/mth...Cool! Now I am a very happily unemployed urchin, driving perhaps 1K/mth and my total electricity cost has actually dropped from 350/mth to 250/mth. And I am now driving my old mileage before taking the job that I quit (which is why I bought the Tesla). So I am way ahead and very happy about it. I have calc'd that it cost me about 4.55 to charge to 235 mi, as opposed to an estimated 55.00 for my Acura, which I just sold.

Essentially, my MS is free to drive. Others have found this with states that offer these time of use charging options. Very cool.

Score!

 

[DonD]

I'll add another data point to this discussion.

After the first annual service on my Model S (~23,000 miles) I totaled the cost of service ($600) plus the cost of the two new tires I needed, plus the total increase in my electric usage (~ $0.12/KWh). Dividing by the 23,000 miles driven I came up with a cost of $0.092/mile including electricity, tires, and service. I'd be shocked to find an ICE that cheap to drive.

 

[exLeaf]

I'll add another data point to this discussion.

After the first annual service on my Model S (~23,000 miles) I totaled the cost of service ($600) plus the cost of the two new tires I needed, plus the total increase in my electric usage (~ $0.12/KWh). Dividing by the 23,000 miles driven I came up with a cost of $0.092/mile including electricity, tires, and service. I'd be shocked to find an ICE that cheap to drive.

Civic NG average 45 mpg, quite often 50 mpg, 28000 miles cost of cng $865, cost of oil change $90, nothing else needed so far, cost per mile is $0.034103. Not a luxury car but quite comfortable for my commute.

 

[DonD]

Civic NG average 45 mpg, quite often 50 mpg, 28000 miles cost of cng $865, cost of oil change $90, nothing else needed so far, cost per mile is $0.034103. Not a luxury car but quite comfortable for my commute.

Thank you for the insight. The Civic does sound like an economical commuter car. I now realize I should have tempered my enthusiasm by saying "I'd be shocked to find a comparable ICE sedan that cheap to drive." :smile:

Note for further comparisons - if we can agree that I did not NEED the annual service (but chose to have it, because of being so early in the production run) my cost/mile drops by 0.026 to only $0.066/mile

 

[majorlance]

Will your in-laws still want you to visit after they figure out why their electric bill is so high, or is that part of your strategy?

Ha! My brother-in-law is a car geek too so we'll go for a spin around the coast... And trust me, the electric bill is the least of what we'll consume once I get into his wine cellar.

 

[brucet999]

I'll add another data point to this discussion.

After the first annual service on my Model S (~23,000 miles) I totaled the cost of service ($600) plus the cost of the two new tires I needed, plus the total increase in my electric usage (~ $0.12/KWh). Dividing by the 23,000 miles driven I came up with a cost of $0.092/mile including electricity, tires, and service. I'd be shocked to find an ICE that cheap to drive.

5 year average operating cost at 12,000 mi/yr (fuel plus scheduled maintenance and tires per my Lexus dealer) for Lexus ES 300h (hybrid 40 mpg) costs $0.077 per mi; ES 350 ICE costs $.111 per mi.

These aren't quite the same class as Model S, a little narrower, shorter wheel base but similar cabin size and creature comfort level.

 

[JohnQ]

Electicity cost is the wild card here. I pay $0.20 per kWh (all in--generation, transmission, tax, etc). Including charging losses and my higher than normal average Wh/mi my energy cost is about $0.065 per mile. An equivalent vehicle (20 mpg, premium gasoline at $3) is $0.15 per mile

 

[spc]

So I finally got my energy monitoring system up and running.

I find very hard to believe that a car this sofisticated and smart one stil have to go buy a energy monitoring system to tell how much energy goes in the car.
That also is not a good solution as it can only tell us when we are at home and not abroad. So how is one going to calculate the true cost.
Hello Tesla.. a few lines of code would give us all the info and even email us a file with the info every month including a gps location one can plugin the cost for that location. and acount for the $0 supercharger.
any gas station will tell you the exact quantity of gas going in the tank, lets make the car tell us what it already knows.
PLEASE..:smile:

 

[PatD]

OK - giving this another shot. Here's a few more stats.

First off, in the past day or two, I drove 29 miles. Used 10.4kWh of energy, averaged 358 Wh/mi.

I put my Tesla on the charger and used exactly 14kWh to recharge. Took a hair under two hours @ 40 amps to recharge.

I'm slightly surprised at the 10.4kWh vs 14kWh, but I have read the same from others. I expected closer to a 20% increase, but hey. . . Also not a huge sample of miles, but I digress.

At my electric rate of $.14/kWh, I used $1.96 for 29 miles, for a cost of $.067/mile. Not bad.

Now my Tesla reports 679.2 total kWh used over 1900 miles. If we say a 30% increase over the kWh reported, we're looking at 883kWh. Now some of that power was from a one-time visit to a supercharge as well as my local service center. But worst case, I've spent about $123 in electric for 1900 miles. At $.064, that's pretty consistent with my number above.

Anyway, still love this car. The fact that I can drive my usual ~10k miles a year and spend about $600 a year in "fuel" is great (Then again, I got my car after the cold winter, so I'm sure that'll hurt next year.) In my old TL, this would have probably cost about $1750 based on my MPG and local fuel cost.

My lifetime avg energy for anyone keeping score is 357Wh/mi.

 

[kuttakamina]

Thank you for the insight. The Civic does sound like an economical commuter car. I now realize I should have tempered my enthusiasm by saying "I'd be shocked to find a comparable ICE sedan that cheap to drive." :smile:

Note for further comparisons - if we can agree that I did not NEED the annual service (but chose to have it, because of being so early in the production run) my cost/mile drops by 0.026 to only $0.066/mile

I think for the quality and class of the car, the operating costs are impossible to beat.
Sure you can compare Model S with Civic NG, but I'm sure if you looked hard enough, you'd find something cheaper than a Civic NG too.
The Volt for instance, a 2015 old model right now, is probably going to have a very low TCO.