Long Term Nissan LEAF Mileage/Usage Review: Once Around The Sun

MAR 31 2013 BY MARK D. LARSEN 33

I am delighted to announce that today marks one year since taking delivery of my Leaf. Happy Anniversary, Ohm My!I have never thought of myself as very materialistic, but I have to confess that I truly, madly, deeply love this EV! It is by far the best car I have ever owned: clean, quiet, comfortable, inexpensive, responsive, powerful, smooth, solid, reliable, convenient, cutting-edge… downright fun to drive. Indeed, it is sooooo enjoyable that I catch myself looking for excuses to run errands, just so I can spend more time behind the wheel.

Even then, it is not as though my daily driving around this desert community has chalked up a lot of miles. You can see the total mileage for this first year by clicking on these readouts from CarWings:

2012 Results (click to enlarge)

2012 Results (click to enlarge)

2013 Results (click to enlarge)

2013 Results (click to enlarge)

Here are the tallies when added together:


8,232.2 miles with 1,513.2 kW used = 5.4 Miles-per-kWh


Other Leaf owners will undoubtedly notice that my average efficiency is the extremely high exception to the rule. The EPA claims that my 2012 model should use 34 kWh to drive 100 miles, i.e., 2.94 miles-per-kWh. Yet to date my 5.4 average translates to only 18.52 kWh per 100 miles! Since the EPA also states that 33.7 kWh of electricity has the same amount of energy as in one gallon of gasoline, this means that my miles-per-gallon equivalent this past year has been:


8,232.2 miles / (1,513.2 kWh / 33.7 per gallon = 44.9 gallons) = 183 MPGe


Can’t beat that!

Except… I can beat that: the even better news is that those kWh came from my solar array, which means that I drove all those miles with truly zero emissions! Coincidentally, I just received my latest utility bill with the final solar reading for this past year taken six days ago. Those utility stats show that my panels produced 924 more kWh than I used to power both my home and Leaf since taking delivery. (As a side note, I will grumble that, unlike in other states, our utility, Rocky Mountain Power, simply zeroes out the yearly total in March without compensating customers for any excess energy “donated” to its grid —a policy that I am adamantly urging our Utah legislators to change.) But getting back to driving on sunshine, here is how my kWh have stacked up for the first year with my Leaf:

kWh Usage Over First Year Of LEAF Ownership

kWh Usage Over First Year Of LEAF Ownership

As the graph clearly shows, the bright blue slice of the pie is 924 kWh larger than the grey and green slices combined. Below are the stats for the miles driven on the kWh in the green slice:

usage 1

Tsk, tsk. Given my miles-per-kWh average, I could have driven nearly 5,000 miles farther with the extra electrons I “donated” to Rocky Mountain Power this past year. I guess I am just going to have to invent even more errands to run in my Leaf next year. Oh… please don’t throw me in that briar patch…!

Of course, one of the key questions that passersby always ask me about my Leaf is the cost to charge it. More often than not, they also want to voice the old, worn-out “long tailpipe” accusation against EVs. Using the above miles and kWh for my Leaf, the current prices in my area, and EPA data, I have calculated the following comparisons of the fuel costs and greenhouse gases:

ghg math

As you can see, if I didn’t have solar panels, and had charged my Leaf from the grid instead, the GHG to generate the electricity at the power plant would have been only about 15% of the amount from my Subaru’s tailpipe and upstream sources, and would have cost less that 1/10th the price of gasoline.

That savings in fuel costs helps lessen the pain in my back pocket for being an early EV adopter. After all, I did pay a hefty price for my Leaf SL last year: the full MSRP of $37,250. Because of other deductions in 2012, my taxable income did not qualify for the entire $7,500 federal incentive, but my pending refund nonetheless lowers the cost to $31,333. Utah also offers incentives for clean fuel vehicles: a whopping $2,500 for CNG cars, but only a paltry $605 for EVs. Still, that will bring the price down further to $30,728.

If I had waited a year, I could now buy an SL model for $34,840, in which case those same incentives would lower the price to $28,318 —a $2,410 savings. Even after subtracting what it would have cost for gasoline to drive my Subaru, I still paid $918 more to drive my Leaf this past year instead of waiting to buy a 2013 model. Was it worth it? Absolutely, in my humble opinion. I have been naïvely contributing to the pollution on this planet for many decades, and consider that a bargain “fine” for my negligence. Besides, I predict that by next year the fuel savings will have eliminated the price difference entirely. Moreover, it ultimately boils down to a matter of principle. Is it worth paying more to help clean up the planet, transition to renewable, domestic sources of energy, and build a better world for future generations? As the old adage says: you get what you pay for.

In case you are wondering, I should clarify that the reason the total miles and kWh in my utility stats are less than in the CarWings readouts up at the top is because of the six days that have transpired since the last reading. Nonetheless, you can see that my average 5.4 miles-per-kWh remains the same. I would love to claim that such extreme efficiency is because I am a world-class hypermiler, but… in truth it probably has more to do with the environment than the driver.

Another caveat I should state is that my odometer mileage likewise differs from the CarWings data. Below is a photo of what the display showed yesterday before plugging in for the night:

Day 365 Of Ownership

Day 365 Of Ownership

I can only guess at the reasons for the discrepancy. The default explanation would be that I have neglected to touch the “OK” button to authorize data transmission to CarWings each and every time I started the car. However, that possibility could not account for the 300 missing miles in CarWings. There were only a couple of times when I failed to select that icon during the first few weeks of ownership, and even in those instances I immediately remedied the error after driving only a block or two. Since then, authorizing CarWings has become so automatic that it is now second nature to reach for the console screen after pushing the start button.

I suspect that a better explanation is that the odometer tallies its miles according to wheel rotation, but CarWings instead relies upon GPS mapping. Which one of those methods is more accurate, I couldn’t really say for certain, but it seems likely that tire pressure, weather, elevation changes, wider or narrower turns, road surfaces and conditions could render an odometer more prone to variability. A satellite, conversely, uses fixed longitude and latitude coordinates to calculate the distance along a given route on the earth’s surface. I suppose that such discrepancies are simply an oddity for drivers with GPS systems to shrug off. Why, even yesterday, as also shown above, the trip odometer clocked 31.1 miles, yet CarWings reports that I drove 30.4. Go figure:

CARWINGS Data

CarWings Data

I am curious to see what the second year of ownership will bring. In a few more weeks, when the daytime temperatures are again in the mid-70s to mid-80s, I plan to do a second quick-and-dirty capacity test to verify if the condition of my battery pack still conforms to the polynomial curve calculated from Nissan’s published benchmarks. And after another summer of blistering heat, I’ll be most interested in seeing if the dire predictions for my capacity bars from the AZ contingent prove prophetic. Of course, by then I suspect that Nissan will have issued the anticipated software upgrade to make the instrumentation more accurate and reliable —which might render the kerfuffle a moot point.

Speaking of that software upgrade, I have already noticed on the CarWings web page that a new set of instructions has appeared for its settings in the vehicle. The upgrade will apparently include a second menu item which my version of the software does not have, as show in the screen dump on the left below:

Freedom From The Daily Disclaimer Button?

Freedom From The Daily Disclaimer Button? (click to enlarge)

 

Apparently, touching that button will open the display on the right above, which allows one to authorize CarWings to automatically transmit data over a 30-day period. As I stated above, touching “OK” every time I start the car doesn’t really bother me, but I know that there are some owners who deem the constant request infuriating. They will undoubtedly welcome this change with a sigh of relief and joy. At any rate, it makes me wonder what other “easter eggs” are in the pending upgrade: perchance the “percentage of charge” readout and the “80% charge now” option via the speedometer display, like in the 2013 models…? Hope so!

In the interim… Ohm My… what EVentures lie ahead!

Editor’s Note:  Like what you read?  Mark’s also has an EV-advocacy site you can check out here as well.

Categories: Nissan, Test Drives

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33 Comments on "Long Term Nissan LEAF Mileage/Usage Review: Once Around The Sun"

newest oldest most voted
Tom Moloughney

Nicely done Mark! EV+PV is a great combo. I’ve been driving on sunshine for over three years now. Can’t beat it!

Delta

There was a pop song about ‘walking on sunshine’. Well you’re ‘driving on sunshine -and don’t it feel good!

Future Leaf Driver

Hi Mark, thanks for the great report on your experiences with the LEAF. That must be great charging with sunshine and never having to stop for gas. I checked out our site, great resource for EV info, bookmarked!!!!

Looks like “Tisa” is riding around in style!!!! 😉

Future Leaf Driver

Hi Mark, thanks for the great report on your experiences with the LEAF. That must be great charging with sunshine and never having to stop for gas. I checked out your site, great resource for EV info, bookmarked!!!!

Looks like “Tisa” is riding around in style!!!! 😉

Mark Hovis

Great report Mark and great title. PV-EV is the ultimate driving experience. I am in my second PV-EV year as well. Here is to a least 24 more more trips around the sun represented by the common solar warranty!

evnow

The electricity used that Carwings shows doesn’t account for the charger inefficiency. You probably used 15% more electricity.

Good average, BTW. My efficiency gets killed in winter 😉

MrEnergyCzar

I do the same but am about even with my Volt and using the surplus solar… planned it that way…

MrEnergyCzar

John Hollenberg

A very good article, only marred by the reference to battery degradation at the end. It may interest you to know that the temperature profile of your area closely matches Fresno, CA. The Battery Aging Model makes the following predictions for remaining battery capacity for your Leaf based on your annual mileage and excellent miles per kwh:

1 year – 91.70
2 years – 88.50
3 years – 85.92
4 years – 83.67
5 years – 81.62
6 years – 79.71
7 years – 77.92
8 years – 76.22
9 years – 74.58
10 years – 73.01

Note that the model is based on unpublished data from Nissan from a reliable source on mynissanleaf.com. Due to your low annual mileage, outstanding efficiency and climate only modestly above the Los Angeles Civic Center reference the model predicts you will do very well (as will I), far from the “dire predictions for my capacity bars from the AZ contingent”. However, this doesn’t mean folks in Phoenix who drive 15,000 miles a year are doing well.

George B

Let it go, John, Mark has proven time and time again that he is a fan of fiction, not fact. That said, I find his self-indulgent narcissism even more annoying than his ignorance. I can understand that not everyone is an engineer, but that does not excuse the type of behavior and language he has consistently used to discredit others, and to draw attention to himself. You would expect more from long-time EV advocates and PIA members.

darelldd

I’ll just have to assume that George is making a knee-slappingly-funny April Fool’s joke. I haven’t found anybody more devoted to LEAF fact than Mark.

George B
Darell, I would certainly hope so. Perhaps the comments Mark has directed at the affected LEAF owners in Phoenix were all in jest also? There is no doubt in my mind that he has done a lot of distinguished work for the EV cause. While the kudos are well deserved, aren’t we forgetting the drivers in the process? EVs are finally getting adopted in greater numbers, which is undoubtedly a good thing. Given this context, some of the owners could encounter legitimate problems. This is all new technology to the world of mass car manufacturing. Why not shift some of the focus from pure EV advocacy towards other goals? Sometimes, both automakers and newly minted EV owners could use some help. Unbiased words of wisdom from prominent EV advocates can make a lot of difference. What happened in this case was the exact opposite. A number of LEAF owners were deeply upset by the commentary and opinion Mark offered on his blog, and on MNL. http://bit.ly/dremnlpost I have been trying to work with him and politely explain some of the technicalities. Although I respect his opinion, he continues to harp the same tunes, even if it’s completely unnecessary. This article… Read more »
IndyFlick

Well done Mark! I slightly undersized my array. The first year I owed SDG&E $38 and the second year I owed them $75. That’s for the LEAF and the house for a year and also includes our NG! I like to tell people I can produce my own electricity, but I can’t produce my own gasoline.

IndyFlick

Mark, you say “my taxable income did not qualify for the entire $7,500 federal incentive”. Do you have an IRA? You can always move money out of an IRA to create a taxable event and then use the EV tax credit to cover it. The result is having tax free cash in a savings account. If you’re under 59 1/2 you move it into a Roth IRA. It sits in that account tax free until you reach 59 1/2.

Ed Marek
“Another caveat I should state is that my odometer mileage likewise differs from the CarWings data… I can only guess at the reasons for the discrepancy… CarWings instead relies upon GPS mapping… yesterday, as also shown above, the trip odometer clocked 31.1 miles, yet CarWings reports that I drove 30.4. Go figure:…” I believe you have guessed wrong, Mark. CW uses tire rotation to calculate miles driven just as the dash odometer does, but it has an odometer error (with stock wheels and tires) of ~2..5% in all 2011. 2012 , and (perhaps) 2013 LEAFs, as was shown (less accurately, due to the low miles driven sample) in your 31.1/30.4 mile report results above. This also explains the same ~2.5% error (assuming your LEAF displays it) in your LEAF’s dash m/kWh (which uses the ~2.5 % under-reported Carwings miles) in relation to the navigation ( which uses the dash odometer miles) screen m/kWh report. Please take a look at the MNL thread below, to confirm whether you LEAF is in fact SNAFU, and for a discussion of how this can improve your understanding of LEAF kWh use reports: “Here are my suggestions, for you and other CW users. All 2011-2… Read more »
Ed Marek

Mark,

I should have started my long comment above with the more important conclusion, on which we agree.

After (almost) two “trips around the Sun”, I also have found that my 2011 LEAF:

“… is by far the best car I have ever owned: clean, quiet, comfortable, inexpensive, responsive, powerful, smooth, solid, reliable, convenient, cutting-edge… downright fun to drive…”

George Bower

Great article Mark. Sorry I missed it. Kayenta is a beautiful place. My wife April has her work at 873 Art Gallery. You should go check it out.. She was featured artist in Sept.

Linda Nicholes

As a long-time EV driver who totally powers her transportation with “gallons of sunshine” from the solar array on my residential roof, I absolutely applaud and validate Mark’s enthusiasm and well-laid out EV + PV facts. I personally have literally not made a stop at the gas station for over ten years. Also conspicuously missing from my life are the hefty utility bills from the 20th Century. (Literally!)

“The California Public Utilities Commission estimates that the state is generating 1,255 megawatts of electricity from 122,516 rooftops. (At peak output, that’s the equivalent energy production of a big nuclear power plant.)” http://www.forbes.com/sites/toddwoody/2012/07/03/how-california-is-democratizing-solar-for-the-99/

Trevor Larkum

Mark, if you’re feeling civic minded, you could set up a public charge station at your place to use up the excess electricity. I’m thinking of doing that at my place in England – I imagine so long as it’s free there are few legal complications.

Trevor

Lawrence Freil

Mark,

Excellent article. I have 6Kw of solar on my roof and just purchased a Leaf. I won’t be generating nearly the power due to the cloudy days, however I do generate enough for the
vehicle and offset my house considerably. In the future I will likely add more solar as our power company actually pays a premium for solar power over and above usage. As for the discrepancy between the car’s miles per kilowatt vs carwings, many GPS receivers ignore the elevation calculations when figuring distance (and speed). You are correct in that tire rotation and inflation can make odometer readings inaccurate. Using a handheld GPS on a level surface should allow you to figure how far off (or not) your speedometer is. I know on my new Leaf, the police speed warning radar is right on with the speedometer.