TMC is an independent, primarily volunteer organization that relies on ad revenue to cover its operating costs. Please consider whitelisting TMC on your ad blocker or making a Paypal contribution here: paypal.me/SupportTMC

Does Fuel Savings really make that much of a difference?

Discussion in 'Model S: Ordering, Production, Delivery' started by Kbsilver, Jul 25, 2014.

  1. Kbsilver

    Kbsilver Member

    Joined:
    Jul 25, 2014
    Messages:
    134
    Location:
    Central NJ
    New board member, right now just a lurker and a dreamer. I am planning for the future replacement for our 'larger' car which is a 15 year old BMW 540iT (wagon with a V8). It seems as 'estimated' savings is always factored into the payment cost. Here in NJ I'm paying nearly 17 cents a KWH (delivered) which when calculating savings over gas, is essentially insignificant compared to the monthly payments on a Tesla. Or does everyone use time of day metering and only charge the car off peak?

    Currently most driving is in our BMW diesel (335D), which averages well over 30MPG. MPG almost doesn't matter to me, it's the TOLLS!! I spend more on Ezpass than I do on gas/diesel. But I see there is a 10% (off peak) discount for low/zero emissions cars. That's almost as much as much as the fuel savings. Does anyone really buy a Tesla because of the lower fuel costs?
     
  2. pgiralt

    pgiralt Active Member

    Joined:
    Jun 16, 2013
    Messages:
    1,476
    Location:
    Cary, NC
    I'm probably not alone here, but for me, there was no way I'd be able to justify or afford paying for a $80k car if it weren't for the gas savings over my previous car. I had an Acura MDX that got around 16 - 17 MPG of Premium Unleaded gas and I drive around 20k miles a year. That's about 1200 gallons of gas a year at around $4 is $4800 a year in gas. Same number of miles at a conservative 330 Wh/m is 6600 KWh of electricity. Add in another 10% for charging inefficiency and you're up to 7260 KWh. Here in NC we pay around 10.5 cents per KWh which comes out to $762.30 a year of electricity. Take that from the $4800 I would have spent on gas and I'm saving $4000 a year on gas. Keep the car for 8 years and that's a $32,000 savings over the life of the car. That's a big deal for me.
     
  3. ElSupreme

    ElSupreme Model S 03182

    Joined:
    Jan 13, 2012
    Messages:
    4,279
    Location:
    Atlanta, GA
    I am on an EV ToU rate. I pay significant amounts (~30¢) per kWh during the summer day (June-September, 2pm to 7pm, weekdays only). Outside that time and all the time in the fall spring I pay a moderate rate (7¢) per kWh. At night (11pm to 7am) every day I pay virtually nothing (less than 2¢) per kWh. Power in general in Atlanta is dirt cheap.

    So in a normal month I spend roughly $20-30 to drive ~3500 miles in my two EVs. I pay an extra ~$50-60 overall compared to my previous rate plan per month. Considering my non-summer energy consumption is ~70% EV this really is a great deal. Compare this with ~$500 in fuel I was spending every month. It makes a huge difference. Considering I plan on having both vehicles 10 years that is $60k savings over a gasoline vehicle. It is a huge impact to me.

    If you don't drive much you wont save much. If you drive a lot you save a lot. And if your power rates are near zero you save un-believable amounts.

    I assumed 20% charging losses for energy consumption, 333Wh/mi (high), $4 gas, and 28 mpg (high for me, low for my wife)
     
  4. Vger

    Vger Active Member

    Joined:
    Apr 10, 2009
    Messages:
    1,685
    Location:
    Salt Spring Island, BC, Canada
    Bear in mind that your fuel savings will be greater than the difference between your home kWh rate and the price of gas/diesel. You will quickly start using superchargers, and they are free. For us, that is a very significant factor.

    In any case, the fuel savings alone are one reason to buy the car, but not the only reason! The driving experience is so far superior to anything we have experienced before. And then there is this little detail about climate change...
     
  5. ckessel

    ckessel Active Member

    Joined:
    Jan 15, 2011
    Messages:
    4,266
    It's a really big difference relative to a similar cost non-EV car. If you're blowing $50,000 more than you normally would on a car in a sort of once in a lifetime thing (like me), you'll never make that back of course, but then with Tesla you're buying a car that's really not comparable to a Camry or some such.

    In my case, in Oregon, I pay something close to .08/Kwh off-peak (4.22 per kwh + 3.xx delivery charge). Over 100,000 miles, compared to a 25mpg car, that'll save me:

    100,000 / 25mpg * $4/gallon = $16000
    100,000 * 350wh/mile * .08c/kwh = $2800

    So I'm saving $13000. And I figure that's conservative as the odds of gasoline going WAY over $4/gallon seems quite high if you look at the historical rise in gas prices. Energy costs go up too, but historically at a MUCH slower rate. I'll probably also put well more than 100,000 miles on my car before I get rid of it. I'm personally figuring 200,000.
     
  6. Larry

    Larry Member

    Joined:
    Jul 28, 2013
    Messages:
    445
    Location:
    East Bay of SF
    I was paying $650-800 in fuel cost per month for my 2 ICE vehicles both of which get 15-20 mpg. Once I got my S costs have dropped to $200-275 and no maintainence costs. I was surprised at the savings. Turns out if I'm home from work or on the weekends my wife takes the S to her work or errands and therfore extra savings. TOU rate makes it $30-40 to charge monthly.
     
  7. Kbsilver

    Kbsilver Member

    Joined:
    Jul 25, 2014
    Messages:
    134
    Location:
    Central NJ
    It seems as most who are using fuel savings as a significant factor for the purchase reasoning have the lower electric rates (remember some areas are taxed to death). I understand and agree on all the other reasons for a Tesla purchase, but for me it would never economically pan out. But if economics were my main criteria, I certainly would not be driving BMWs now. It's just the on-line pricing seems to really make a big deal about the fuel savings. This is one where YMMV, at least until there is a supercharger in every neighborhood.
     
  8. ckessel

    ckessel Active Member

    Joined:
    Jan 15, 2011
    Messages:
    4,266
    You'd have to live in an insane area for it not to be significant. Even if my rates were double, so .16/kwh, I'd still save over $10,000 over 100,000 miles. No, you're not going to get a Tesla to save money. The point is that Tesla total cost of ownership is at least on par with, if not significantly better, than it's competition.

    Unless you're a billionaire, the economics matter no matter what your income level. When you get your first job out of college and stop eating Top Ramen, it's not like you suddenly don't care what food costs.
     
  9. FlasherZ

    FlasherZ Sig Model S + Sig Model X + Model 3 Resv

    Joined:
    Jun 21, 2012
    Messages:
    7,019
    I replaced a 14.5 MPG Chevy Suburban with the Model S @ 9c/kWh to haul my family of 6 around. Over 150,000 it'll save me $35-40k @ $3.80 average per gallon (welcome to Illinois!)

    That's a big savings.
     
  10. Lloyd

    Lloyd Active Member

    Joined:
    Jan 12, 2011
    Messages:
    4,885
    Location:
    San Luis Obispo, CA
    The savings becomes more dramatic when you have enough solar to cover your electrons also. But then you have an investment in the solar panels as well.
     
  11. GoBlue88

    GoBlue88 Member

    Joined:
    Apr 1, 2014
    Messages:
    638
    Location:
    San Diego area
    #11 GoBlue88, Jul 25, 2014
    Last edited: Jul 25, 2014
    Yep. Although I'm charging my car during super off-peak in San Diego ($0.16/kWh), last month because of solar generation credits my average cost per kWh for my entire bill was between $0.02 and $0.03 per kWh. That figures to go up in the winter, but even then with all the sunshine we get out here, I don't think my average cost will exceed $0.16/kWh in any month.

    Assuming an average of $0.10/kWh for the 10 years I plan to own the car vs. a conservative $4/gallon for the high octane fuel I had to put in my Lexus IS 350 that I was driving previously I arrive at the following:

    Miles per year: 10,000 (I've been very consistent on this for the last 5 years - I don't drive as much as some of you guys)

    Lexus IS 350 mileage: 21 mpg (sweet car, but a gas hog)
    Gas cost per year at $4/gallon: 10,000/21 * 4 = $1,905

    MS mileage: 330 Wh/mile. At 10% charging inefficiency to get 363 Wh/mile = 0.363 kWh/mile
    Electricity cost per year at an average of $0.10/kWh: 0.363*10,000*0.10 = $363

    Difference = $1542/year. 10 years = $15,420 savings. Assuming gas cost doesn't increase faster than electricity, even though we all know it does. Also assuming I never charge for free anywhere, even though I already have.

    Also doesn't take into account no oil changes, so smog tests, no brake pad replacements, etc.

    Still may not be the best outcome given what I paid for my Model S, but holy hell will this be sweet for anybody buying a Model III.
     
  12. Kbsilver

    Kbsilver Member

    Joined:
    Jul 25, 2014
    Messages:
    134
    Location:
    Central NJ
    I just saw the light. Here in NJ we have some of the nations highest electric rates, yet some of the lowest fuel costs. You said even if your rates double to .16kwh, well mine is already over that. With TOD metering it does go down to about .08 per. I'm still saying Tesla is a brilliant execution of a TEV, just that in my circumstance, the energy savings is not that significant for my 15,000 miles a year. (If you said I got all the tolls for free, THAT would be a big). The fact that my vehicles already get decent MPG makes the difference less dramatic. Heck our 15 year old V8 station wagon averages over 20.
     
  13. ckessel

    ckessel Active Member

    Joined:
    Jan 15, 2011
    Messages:
    4,266
    Yep, you're definitely in a zone where isn't not going to save you much. At least not today. Might be worth reviewing though in a few years and seeing if things have changed.
     
  14. GoBlue88

    GoBlue88 Member

    Joined:
    Apr 1, 2014
    Messages:
    638
    Location:
    San Diego area
    Model S may be too expensive if you don't drive enough miles like some of the others here, but I think if you run the numbers on Model III, there's no way that the savings won't be very significant.
     
  15. ckessel

    ckessel Active Member

    Joined:
    Jan 15, 2011
    Messages:
    4,266
    Actually, with the Model 3 the savings become even less significant because it's comparing against smaller, more fuel efficient vehicles. The Model S compares against gas hogs.

    Now, if gas is at $6/gallon in 2017 (which is not that big a stretch of the imagination), that has a big impact on the calculations.
     
  16. derekt75

    derekt75 Member

    Joined:
    Jul 16, 2012
    Messages:
    592
    Location:
    San Jose, CA
    $0.17/kWh is still cheaper than $3.50/gal.
    At 0.33 Wh/mile and 30 mpg, that translates to $0.06/mi and $.12/mi.
    Sure $1000/year in savings isn't huge compared to a lot of things, but it's still $1000/yr at 17k miles/year

    I agree that it's impossible to justify paying $30k more for a car to save $1k per year.

    Other costs also make a difference (tires on the Tesla might be more expensive, while brakes will be cheaper).

    You can likely do better than $0.17/kWh in NJ. (My marginal electric rate was $0.40/kWh a few years ago, but I charge my car for about $0.10/kWh).
    You noted that you could get it down to $0.08/kWh. That's still only $1500 or so per year savings at 17k miles/year.

    In summary, your transportation fuel bill will be significantly lower if you buy a Tesla. but if you currently only spend $2000/yr in gasoline, you're not going to save more than $2000/yr in fuel. :)
     
  17. GoBlue88

    GoBlue88 Member

    Joined:
    Apr 1, 2014
    Messages:
    638
    Location:
    San Diego area
    Disagree as a broad point. Model 3 will allegedly start at $35K, but I bet most people will be adding options that will take it well into the $40K range.

    I had a Lexus IS 350 which would be precisely in the Model 3's range of competition (about $43K nicely loaded). It gets lousy gas mileage for the size of car it is. If Model 3 was available, that's what I would have purchased instead of Model S, and that fuel savings would have been far more compelling off the price of the car.
     
  18. Zythryn

    Zythryn MS 70D, MX 90D

    Joined:
    Mar 18, 2009
    Messages:
    1,660
    Location:
    Minnesota
    As you have already mentioned, the answer to your own question is, it varies from person to person.
    For any electric, total cost of ownership is an important consideration when buying a car. As long as the calculations are shown, I far prefer it over not having it available.

    I know a limo driver who is looking at saving 8-10 thousand dollars a year. I'm saving about $3,000/year. That adds up quick.

    However, the single best reason to buy the Model S is, overall, it is the best car available on the market today.
    The money savings are just frosting on the cake.
     
  19. GoBlue88

    GoBlue88 Member

    Joined:
    Apr 1, 2014
    Messages:
    638
    Location:
    San Diego area
    Yeah, replacing a Prius obviously won't translate in quite the fuel savings over replacing a Lexus IS 350.

    That said, you'll be taking a huge step up in acceleration, driving pleasure, and coolness factor! :cool:
     
  20. ItsNotAboutTheMoney

    ItsNotAboutTheMoney Active Member

    Joined:
    Jul 12, 2012
    Messages:
    4,502
    Location:
    Maine
    Depends on the buyer they're attracting.

    Mid-size BEV v mid-size luxury car?

    Sure, my Prius costs 6c/mi to refuel at current prices (excluding tax, which hopefully will be changed), but replacing 30mpg would be (excluding taxes) going down from 10c/mi around here. Could be 5c/mi less in fuel , so $500 for every 10,000 miles. Not extraordinary, but certainly significant.

    However, if luggage spaces remain relatively large for the form factor it could attract more downsizing, particular for the Y.
     

Share This Page