BMW i3 Is U.S.’ Most Expensive EV Per Mile Of Range – Tesla Model S 85 kWh Is U.S.’ Cheapest

3 years ago by Mark Kane 58

How much are you paying per mile in an EV? - Mojo Motors

How much are you paying per mile in an EV? – Mojo Motors

Tesla Model S

Tesla Model S

Mojo Motors, in looking for an electric car with the highest range bang per buck, assembled a graph comparing different EVs with Cost Per Mile of Range, or CPMR factor.

CPMR takes into consideration just the United States, only 2014 model year EVs and does not include state or federal tax credits.

Tesla Model S 85, thanks to its large battery pack, is characterized by the lowest CPMR of just $302 per one mile of EPA range. The 60 kWh version is between the Chevrolet Spark EV and the Nissan LEAF.

On the other end of scale is BMW i3, which is at $510 per one mile of EPA range. Not good. The i3 is followed by Toyota RAV4 EV and Mercedes B-Class electric.

In the not premium segment, the best is Chevrolet Spark EV – $325 per one mile of EPA range. Nissan LEAF exceeds $340.

“What these metrics don’t account for is the extra gizmos and do-dads you get in something like the i3, the extra cargo capacity of the RAV4 or safety features of a Fiat 500e when you run over a zombie on the side of the road. It is simply a comparison between the price of the vehicle and how far you can actually drive it between charges. In reality, a shopper in the market for an EV probably won’t be comparing the Tesla Model S with the Chevrolet Spark EV, but if you’re someone who wants the most bang for your buck, cost per mile range can be a valuable metric.”

Mojo Motors

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58 responses to "BMW i3 Is U.S.’ Most Expensive EV Per Mile Of Range – Tesla Model S 85 kWh Is U.S.’ Cheapest"

  1. Mike says:

    Concurrent with this there should be a PURE Miles per kWh chart, where the i3, of course, will come out on top.

    Which explains why the i3 was designed the way it was, with advanced materials for lighter weight.

    1. David says:

      This article is talking about purchase cost of the vehicle. All electric vehicles are so efficient compared to any ICE that efficiency between them isn’t very important. i3 needs more range. Efficiency won’t help if people won’t buy it because its too expensive to start with or if its range isn’t sufficient.

      1. Marty says:

        David, sorry, no electric vehicle is as efficient as an internal combustion engine. First, and electric vehicle wastes minimum 30% of the electricity it uses, because when you are charging the batteries, they only absorb about 85% of the energy – the rest is wasted as heat. Second, when you discharge them, the electric motors and controllers waste a lot of energy as heat.

        And finally, this electricity (at least in the US) came from fossil fuels to start with, nearly half if the electricity in the US still comes from burning coal!!!!!

        1. Alan says:

          I’m surprised no one had responded to Marty yet … I’ll give him the classic rundown as to why electric cars really are a dramatic improvement over conventional gasoline cars.

          First, electric motors are far more efficient than internal combustion engines; they typically have an an efficiency of 90%, while internal combustion engines peak out at 25% at peak efficiency – and often, under real driving conditions, have 15% efficiency. There are battery and transmission losses for electricity, but gasoline needs to be refined and transported, too – resulting in similar, if not greater “transmission” losses. Regenerative braking provides a huge efficiency improvement for electric cars and hybrids over conventional gasoline vehicles. Granted, coal is used to generate a large amount of the electric power in the US, and in localities where it dominates, the advantage of using electric cars is minimized; but in places like California, or the Northeast, use of renewables, natural gas, and nuclear power cause electric cars to be dramatically lower well-to-wheels emissions. A modern natural gas power plant, operated at peak efficiency, can be 60% efficient – far better than the motor in your car. Finally, since electric power can be generated from a variety of sources, using it frees us from paying money to oil producers, which are – all-too-often – oppressive regimes.

        2. danwat1234 says:

          Marty, don’t be dumb. Engines get very hot when running. Electric cars do not, thus way less wasted energy.

          The EPA MPGe of the vehicle takes into account charging losses. Yes a lot of electricity is made by fossil fuels, though in some states like Washington state, there are a lot of renewables in the mix.

          YOu have to account for the energy and pollution needed to capture crude oil and to convert it to gasoline and to transport it.

          Electric cars are where it’s at. Hydrogen is less efficient than straight electric as well.

        3. Charlie P says:

          Marty, I own an electric car, but I’m not an EVangelist. Many EV owners get quite irritated with me because I insist on being factual.

          The facts about efficiency are as follows.

          1. A gas car converts about 21-22% of the heat in gasoline to motion. The rest of the energy goes into the atmosphere as heat, vibration, and noise.

          2. A diesel car converts about 30% of the heat in diesel to motion. The rest of the energy goes into the atmosphere as heat, vibration, and noise.

          3. An electric vehicle system — the inverter, the rectifier, the battery — converts 75% to 80% of the energy in electricity from the plug to motion.

          4. The mix of fuels used to generate electricity in the United States, as of 2013, was 39% coal, 28% natural gas, 19%^ nuclear, 7% hydro, 4% wind, 2% solar, geothermal, and biomass, and 1% petroleum. When all the heat efficiencies are combined, an EV converts about 35% of the heat in the various fuels to motion.

          5. An EV is therefore about 1.6 to 1.65 times as efficient as a gas car, and about 1.17 times as efficient as a diesel car.

          6. Most of the EVs in the United States are sold in markets where hydro, wind, and solar have a higher share of the total generation mix. I haven’t done those numbers because the EV numbers are so small, and because I prefer to analyze EVs as “mainstream” vehicles even if that’s not the case right now.

          That much said, if you looked at TODAY’s EV fleet, given where most of the cars are located, I think it’s fair to say that the efficiency comparisons are better than the “U.S. average base case.”

          Those are the facts. You can accept them if you want, or deny them if you prefer. The EVangelists commonly look at only the equivalent m.p.g. numbers, which are about 3-1/2 times higher for EVs than for equivalent gas cars, and impute the ratio to efficiency, without including the efficiency ratios for electricity production.

          When presented with these facts, EVangelists will sometimes counter by pointing out the energy used for oil exploration, drilling, transportation, and refining, without including similar numbers for the energy used for the exploration, mining, transportation, refining, and purification of coal, natural gas, and uranium.

          EVangelists will also argue that EVs would be far more efficient than gas or diesel if renewables were a higher percentage of the electric generation mix. What they prefer not to discuss are the very real limitations on renewables due to their intermittent output and MUCH higher expense, especially if power storage is included.

          In the real world, until the storage issue is dealt with in a cost-effective manner, the percentage of power generated by renewables is unlikely to change by a great deal. And even if storage is cracked, the sheer inertia of the system — which in the U.S. generates 4 quadrillion watt hours a year — will ensure that really big changes will take quite a while to implement.

          THE BOTTOM LINE

          1. Electric vehicles are materially more efficient than gas and somewhat more efficient than diesel.

          2. Electric vehicles are not so much more efficient that they’ll make very much of a difference in the next 50 years, even if widely adopted.

          1. Tom C says:

            if you want to look at facts, you have to look at the gathering of the gas fuels too. And besides the many other things already challenged about your”facts”, you miss the simple fact that many states, and the EV users in those states, use suppliers who provide only Wind or Solar produced energy.

            1. Charlie P says:

              “You have to look at the gathering of the gas fuels too.”

              I realize that my post was long. Please re-read it. I discussed the issue. Maybe you didn’t see that part.

            2. Charlie P says:

              “you miss the simple fact that many states, and the EV users in those states, use suppliers who provide only Wind or Solar produced energy”

              ——

              I also discussed regional variations in power generation. You really, really need to re-read what I wrote.

          2. Alan says:

            Your numbers are reasonable, with one major item overlooked:regenerative braking. Yes, hybrids take advantage of it, but it’s not used with all gasoline cars, but it is with electrics. In a locality with coal power, a hybrid may be cleaner than an EV.

            One thing about an EV, however, is that its battery could be charged with renewable like solar when there are clouds passing overhead. Battery storage means that EVs are well suited to handling some intermittency from the power source. There are some schemes out there for using EV batteries as a backup power supply for a house. For this reason, EVs may be part of a solution enabling a cleaner grid in a way diesel cars never could.

            1. Charlie P says:

              I don’t have the numbers on regen. All I can do is guess, based on experience and observation. I think it adds 10% to 15%, by capturing energy otherwise dissipated by brakes.

              As for solar, do you realize that it accounts for 0.8% of the electricity generated, as of the first five months of 2014? It is less than trivial as a power source — much less than the burning of wood, for example.

              http://tinyurl.com/mv7zncp

              As for EVs handling intermittency because they have batteries, that’s not how it works in actual use. They are no different than other appliances; they are plugged into an outlet. Power dispatch is handled by the grid, which by the way is an essential component of “net metering” schemes.

              Similarly, the idea of using EV batteries as backup has a nice ring to it until you look more closely at the realities of the batteries and how and when the cars are actually used. EVangelists tell themselves all kinds of tales.

        4. Jon Allen says:

          Wow… You are mis-informed. What you say may possibly be true of an EV from the 1970’s early 1980’s with resister controls and lead-acid battery pack (only 80% efficient.) Maybe you ment to say 95 % efficient which is closer to today’s EV batteries. Today’s AC motors and hi-tech control systems as so much more efficient than the controls of even 5 years ago.

          Perhaps we are just having fun with numbers… Imagine an EV having a cooling system as large as a gas or diesel engine to get rid of all that waisted heat energy that makes that technology start at only 20%… And 60% of the waist goes out the tail pipe…

    2. James says:

      Mike, the lightweight materials provide BMW with the opportunity to install a smaller battery pack – which saves BMW money, not you and I. Bottom line is that i3 is an 80 mile or so BEV. Obviously, it’s cost to the consumer to drive 80 miles is much more than the same consumer driving 80 miles electric in a LEAF or SparkEV. So far, I haven’t seen an i3 advertised at the $42,000 MSRP so many online like to quote. Actually, the base BEV runs more than that, all the way up to $56,000+ for the ReX model with all the goodies.

      Your characterization of “PURE” EV miles doesn’t make sense.

      1. ELROY says:

        And how do you know that it doesn’t cost more to make the car lighter, than simply putting a few more kWh of batteries in the car? But again, the key thing here is the i3 is the most efficient in it’s class, and the quickest.

        1. James says:

          I’m looking forward to your article depicting how much time of ownership it’d take to make up the price difference between i3 and LEAF. All this “most efficient” talk seems silly since electricity is so much cheaper than gas. In my neck-o’-the woods, most electricity is from clean hydro and comparatively even lower priced!

          I think “most efficient” is a claim that requires both initial price ( cost ) and cost of service, replacement parts and repair ( such as CFRP body repair ).

          If we don’t factor those expenses in, how can we truly define “efficiency”?

          1. Brian says:

            Efficiency and TCO are completely different metrics. Let’s not dilute either’s meaning by trying to mash them together.

            The i3 is hands-down the most efficient car on the list. But what does that mean? Not too much – they are all far superior to the best ICEV (i.e. Prius). Plus electricity is relatively greener than gasoline. The bulk of the gains are simply getting from gasoline to electricity. The rest is just icing. Expensive icing.

            1. Spec9 says:

              Yeah, the i3 is the most efficient . . . but so what? It is pretty meaningless since any money-saved by its more efficient operation is more than eaten up by its higher sale price (at for mileage less than 100K).

              Now it is it great that its efficiency allows BMW to get away with a smaller batter for an equivalent range but it really sucks that they did not provide the OPTION for getting a bigger battery so you could have a nice long pure-electric range.

              1. Mike says:

                It’s light weight translates into quicker starts.

                Look, your point being efficiency between EV’s doesn’t matter.

                Car sales are based on first, what one can afford.
                I for one cannot afford a Tesla or an i3, but, I will admire the Tesla for it’s range, and the i3 for it’s efficiency. Say you want to move into a smaller home, but can afford 2 Tesla’s or 2 i3’s for you and your wife. Saving 40 kWh per day makes a big difference as to your solar panel needs.

                BMW built an i3 knowing what it’s typical buyer can afford, and if a BMW buyer does buy an i3, they’re doing great things for themselves and the planet.

                Now, your point on the Leaf. Goshen deserves some credit here for making a nice, lux riding EV, for the top 60% of the buying public.

                And GM Knows the American buyer. With a vehicle that you can’t screw up. There’s a gas gauge there, you can get great 40 miles of EV bang for your buck, and then hit gas stations on your drive from Philadelphia to Reno.

                Then there’s the Ford CMax Plugin, which is a BEST BUY for most Americans, who really only need 20 miles of electric most days.

                This metric should be posted with other metrics, it clearly isn’t the best metric out there, as most Americans don’t need more then 40 miles of range.

              2. FFY says:

                If it was all just about nickles and dimes, everybody would be driving iMiev or cheap Hyundai ICE cars, and nobody would buy Tesla cars. 😉 But obviously there are other factors, such as performance, fun, fascination with innovative technology or whatever floats your boat. Or someone has the primary goal of reducing their CO2 footprint as much as possible, or perhaps run a net zero energy household from their solar cells, in which case 25% reduced energy consumption compared to another EV can make a major difference.

                Personally, I like the direction BMW is taking with the i-series primarily because I think that is where the market in general needs to go. Cars have gotten heavier and heavier in the last few decades and basically nullified the gains that have been made in engine and drivetrain efficiency. This needs to stop. In the big picture, the fleet consumption is what counts; if millions of cars use 25% less energy each, that makes a huge difference.

                1. Mike says:

                  Yes. The only time someone would be using this metric, and the only time it’s valid, is when you’d be buying an Electric Delivery Truck.

                  Purchase Price per 1 Mile of Range?
                  And even then you have to ask your self, between candidate A and B, do they First have Sufficient Range, you might say, only EV’s with 120 miles of range qualify for purchase.

                  Then you’d say, Of the two candidates, which is cheapest per one mile of Range.

                  In that case only 3 candidates would qualify from this chart.
                  1) Toyota
                  2) MB B Class
                  3) Tesla

                  In that case the MB B Class wins.

                  In what real world comparison would you use this test?

      2. JRMW says:

        James,

        come to Minnesota. We have tons if i3s for sale for around $43k.

        The i3 with Rex runs about $47k, but several are on sale for $45k.

        http://www.motorwerksbmw.com/inventory.aspx?_new=true&_makef=BMW&_location=8437,8441&_model=i3

    3. david_cary says:

      I’ll take a gander.

      The number I found is 117 mpge for an i3 and 115 for a Leaf.

      Just for kicks, I’ll plug in my driving. 10k miles a year and 5 cents a kwh.

      I’ll go and round in the i3’s favor and call it 2% more efficient.

      I pay about $120 a year so the i3 will save me just about $2 a year (I rounded in the Leaf’s favor this time).

      So I got a SV for just about $32k with taxes – $7500 or $25500. We can go with $50k for the i3 (with taxes) or $42500 after rebate.

      So the cost difference is $17k. So right around 8500 years to make up the difference.

      Ok – don’t use $$, use carbon. Think of how many solar panels would it take to make up the $2 of electricity a year and what that would cost…. $50

      1. MTN Ranger says:

        Officially 126/101/114 city/hwy/combined MPGE for Leaf and 137/111/124 for the i3.

        http://www.fueleconomy.gov/feg/Find.do?action=sbs&id=34699&id=35207

        1. david_cary says:

          Wonder how I found the numbers I did? 2013 Leaf explains the 1 mpge difference but the i3 was from a EPA sticker.

          Brings it closer to 1000 years.

          1. david_cary says:

            Bet the numbers I had were for the REX and your numbers are for the non REX

    4. jj says:

      idk they are all very expensive… And aside from the Tesla, the range is pretty much useless to the average suburban driver.

    5. Compumagic says:

      I get 5.1 miles per KWh average over the past 3700+ miles I have driven my i3 REx. I drive very efficiently.

  2. john yanoscik jr says:

    2013 coda 111 miles per charge
    $10,000 purchase price

    enough said

  3. Bonaire says:

    Marketing math.

    Looks like someone is “using math to pump Tesla”. Sure, the scale indicates miles of range per dollar. However, who buys cars on that scale?

    What if a driver drives 40 miles per day – then the scale could be “per miles of range needed per vehicle driving day (PVDD)”.

  4. JRMW says:

    I’m not sure if this measurement is very useful.
    Car price divided by range?

    In the end the graph tells us something we could have known intuitively.
    -luxury brands cost more
    -SUVs cost more than sedans
    -Sedans cost more than the teeny tiny commuters

    and Tesla, which focused on RANGE, is able to produce a car that has a lower purchase price/range ratio than others. This is more of an artifact of having a high denominator than anything else. It’s more playing with numbers than anything else. (although I applaud Tesla for doing this, it’s really not comparable to any other car on this list).

    I think the only minor surprise is that the Fit and Focus are on the more expensive side but again it’s relatively meaningless measure.

    1. Brian says:

      For the sake of accuracy, the Fit EV price dropped by 1/3 (lease only at $259 vs $389), so it is actually the champion here at $297.38 per mile. Not to mention miles are unlimited, charging station is included and comp/collision insurance is provided. As to whether the chart is useful, it would be like comparing sports cars based on speed per dollar spent where the mitsubishi beats the porsche based on a cost of 1/4.

  5. Warren says:

    First, only three of the cars on the list are available outside of Unicornland: the Leaf, i3, and Tesla.

    Second, if you deduct the $7500 federal tax credit, the Leaf is the clear winner, as the credit has almost three times the impact on per mile price on the Leaf.

    1. Warren says:

      Yes, I know there are other cars on the list that are theoretically available. But there are none available for test drive on any lot here in central Virginia.

      With the exception of the Tesla, nobody is going to buy one of those without a test drive!

      1. Warren says:

        And, for the base model i3 Rex we test drove, at 150 mile range, it is the best bargain going! A couple hundred pound scooter motor you will hardly ever use vs 900 pounds of extra battery you will hardly ever use.

        1. James says:

          Yet, who can ASSUME how much another person will ever use? Your assertion appears narrow – and basically made around your needs.

          Many of us need more than 80 miles EV range, and 50 miles or so on the highway until we fill up our tiny, tiny tank.

          i3 or i3ReX is a commuter car – a city car.
          It has significant limitations. I’d take more battery any day vs. a 2 cyl. scooter range extender. Getting off the freeway every 40-50 miles on a long trip is ridiculous. Any way you look at it – you have
          basic LEAF limitations – or any other 70-85 mile BEV. So why pay THAT MUCH?!!!

          There is a lot of talk in defense of i3 quoting “premium brand”, or “luxury”. I wouldn’t call i3 luxury by any stretch, but BMW is considered a premium ICE brand that makes a whole lot of ICE CUVs they call “SAVs”, and a large line of ICE sedans and wagons.

          Many would define luxury as having range to go where you want, when you want. In that respect, solutions like the Volt or Model S provide much more of that luxury.

          i3 has so many shortcomings, not to mention it’s weird, impractical doors. But if i3 intrigues you – how much does your perceived luxury brand deserve such an exhorbitant cost? i3 does have a nice interior and clever lightweighting, such as in the seats.
          It just doesn’t go from point A to B any better than options that cost so much less.

          Again – “quicker” ( sigh ) – even testers admitted that once they spend time with i3, they realized it seemed quicker perhaps because it was lighter and dartier – feeding back more road noise to the driver. Now think about that awhile. If we take sound insulation out of a compact car and perhaps remove upholstery and lighten the seats, it would provide similar feedback.

          So my point has always been – does all that lightweighting benefit you, or BMW? Smaller battery pack equals less cost for them.

        2. Dan says:

          If you are including range-extenders, the i3 is always going to lose (badly) to the Volt.

          1. Warren says:

            Living in the country, I would be burning gas every day with a Volt, a proposition I wouldn’t consider.

            We didn’t buy the base Rex because I am betting GM will come out with a Sparkish compact with a real 200 mile range for less than the Rex. If not, that base Rex will probably still be on the lot then, as the dealer has sold two fully loaded i3s, one a Rex, already. It seems BMW buyers won’t be seen in a base model. 🙂

    2. Matt says:

      The Ford Focus Electric is too… much smaller numbers of course, though 🙂

      1. Warren says:

        Not here. You’d have to order it, as no dealer here has ever seen one!

  6. JohnMo says:

    What bull**** method is this !

    1. MikeM says:

      O.K. JohnMo. Dissatisfied? Want meaningful stats? – How about this:

      Length (inches) of wheelbase per Diameter (inches) of steering wheel.

      Pretty sure Tesla nails that one too!
      Also, it seems like the less useful the measure, the more comments it spawns.

  7. John Hollenberg says:

    The proper metric would be to at least include the federal tax credit in the calculation. That would put the Spark EV and the Leaf as the two lowest. If state incentives were added, the gap would be wider still.

    1. io says:

      +1

      Not that it makes the resulting numbers any more useful anyway… Next, price per kg/lb anyone?

  8. Brian says:

    Useless measure. This is more for a post-purchase look at how much you got for your money, but it will never be used to make a decision on which vehicle to purchase!

  9. David Murray says:

    But what if you calculate it based on the i3 Rex? Things suddenly change quite a bit there. And since any range above 80-ish miles will be used rarely (by most people), the Rex is just as good IMO as having another 80 miles of battery range that is seldom used.

    1. Dan says:

      The i3 REx has less EV range than the BEV i3. Unless you’re talking about including the range on gasoline, in which case we would also have to add the Volt, Fusion Energi, C-Max Energi, and Plug-in Prius… all of which would immediately dominate the i3 REx (and everything else on this list) in price per mile of range.

      1. David Murray says:

        Yes, I was referring to using gasoline. Hence, bolstering my point that I believe the range extender is currently the most economic way to add more range to a vehicle without needing to add dozens of kilowatt-hours of extra batteries.

        1. Josh says:

          But would you drive an REx from Dallas to Houston? I think the Volt is still a better one car family vehicle, while the i3 is just the ultimate commuter car.

          The i3 really fits into a new segment and should expand the market. They obviously were not optimizing for $ / EPA mile, while Tesla and Nissan probably were.

  10. Thanh Lim says:

    There’s lies, damn lies, and then there’s statistics.

    Why not look at the real #, like total cost of ownership. Take the samples at 10/15/20K a year with a standardized electrical cost for charging?

    (Let’s not take into account the super chargers or the free charging by Nissan since that’s not how most people charge.)

  11. Jouni Valkonen says:

    This is a good reminder that electric cars makes perfect sense among the luxury car category, base price above $50 000.

    Therefore EV incentives should be directed for the cars cost more than $50 000. Best way is that luxury ICE cars face severe car tax, so this would increase the competive advantage of electric cars.

    If the most expensive 2 % of all cars sold were electric, this would mean that global EV markets were more than million cars per year.

    This is lot more EVs than what positive EV incentives have helped to generate sales. Simply put, with negative EV incentives one gets more bang for the buck, because the rich 1 % does not mind if their car costs $60 000 or $120 000 or if it is fully electric or not. Only the car quality matters.

    1. pete g says:

      2% of US auto sales is only 320k, and I do not see oil company executives buying electric cars.

      1. Mike says:

        Oil Industry CEO’s run their companies with a Political Agenda. Like investing in the ultra low profit Canadian Tar Sands fields.

        And ignoring solar power at just 5 cent per kWh now in Texas, in their back yard.

  12. Spec9 says:

    I think it is a pretty interesting metric. And many of those with the lowest dollar/range-mile cost are the best-sellers (Leaf & Tesla 85KWH). I would think the Spark EV would sell pretty well if it were available everywhere and was marketed a bit.

    Range & price are certainly the most important intertwined factors

  13. pete g says:

    Just for laughs change the title to electric only range, and add the plug-in prius. It must be the best it’s the most expensive.

  14. tiburonh says:

    Cost per mile of range is an interesting but ultimately irrelevant basis for comparison.

    If one wants to truly compare the relative efficiency of the different pure electric vehicles, then one needs to compare the total ownership/operating cost per mile. I haven’t seen that done yet, but I suspect that the i3 will beat the Tesla here. Its purchase price is much less than the Tesla’s (especially when one factors in the federal and state tax credits/rebates), and its MPGE is way higher than the Tesla’s.

  15. malarchist says:

    How is this metric of any practical use? So you pay $40k for your BMW, you drive 80 miles, and then you recharge it! And then you drive some more. If your commuting patterns require an EV with some minimum range, then it automatically puts some cars completely out the question for you.

    “Cost per mile of range” is a completely bullshit metric and has no practical meaning whatsoever. What does make sense is “Cost per miles which can be travelled in lifetime of vehicle”, but then again, we don’t know enough about the reliability of these cars to know how long they last for

  16. Tummy says:

    The metric looks different when you factor in state and federal tax incentives where it has a greater effect on lower priced cars.

  17. Charlie P says:

    Not that you’d ever expect a journalist to get this, but when every electric car must contain an expensive battery, the cost of the battery (even a larger one) relative to the rest of the car will go down as the car gets more expensive.

    Therefore, you’d expect a Tesla Mpdel S to cost less per mile of range than a cheaper car with a smaller battery. This could all be explained with algebra equation, but reporters never liked algebra very much.