Mike's wife's monthly Kona EV efficiency report

Discussion in 'Hyundai Kona Electric' started by navguy12, Aug 30, 2020.

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  1. navguy12

    navguy12 Well-Known Member

    I'm starting a thread to follow the "grid to wheels" efficiency of my wife's new 2021 Kona EV (Preferred).

    I run a thread for my 2018 TM3 and it will prove interesting, to me anyway, to compare the real world energy efficiency between the two vehicles.

    Obviously, I will only post Kona relevant information here, but for background on the TM3 efficiency one can check out this thread: https://teslaownersonline.com/threads/mikes-monthly-model-3-efficiency-report.8945/post-289980

    My first month of data for the Kona is somewhat abridged as we took delivery on 20 Aug 2020 and since the dealership didn't fill up the battery, we had to do that at home.

    If there is a more efficient way to draw information from the Kona than I have chosen (without the use of third party hardware/software), please speak up. :)

    Aug 2020 results:

    aug2020 raw data.PNG

    Note: the above data includes a top-up to 90% (34 kWh) the evening we took delivery of the car.

    "Real Upload" page also shows lifetime difference (blue cells at top):

    aug2020 real upload data.PNG
    The above information was cobbled from the car's trip odometer. The "real" data is showing 80 kWh minus the 34 kWh we required to top up the battery (to 90% SOC) the evening we took delivery of the vehicle.

    Raw data for Aug 2020:

    aug2020 odometer.JPG aug2020 in line meter.JPG aug2020 eyedro.PNG

    Note: the raw "Eyedro" monitoring system is displayed only for reference at this time. The 01-20 Aug 2020 data that shows up on this shot is because the sensor for the system was being used to monitor our kitchen stove...thus the total energy used shows "89.289 kWh" versus the raw "dumb" monitor that shows "80 kWh" that flowed from the circuit breaker panel towards the Kona.

    Summary costs as of 31 Aug 2020:

    aug2020 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $161.1455 - $155.408 = $5.7375/km

    Obviously, the above (outlandish) cost per km becomes smoothed out with more distance traveled.

    The above assumes "zero" value for the vehicle until it is actually sold at some future date.

    For comparison purposes, the costs for my wife's previous car, a 2012 Toyota Yaris:

    Capture.PNG

    Total operating costs, per km (total costs minus capex costs):

    $0.3850 - $0.164 = $0.221/km.

    So, lets see how many months/km must be driven before the Kona operating costs are less than 22.1 cents per km.
     
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  3. navguy12

    navguy12 Well-Known Member

    Sep 2020 results:

    sep2020 raw data.PNG
    "Real Upload" page also shows lifetime difference (blue cells at top):

    sep2020 real upload data.PNG
    Raw data for Sep 2020:

    sep2020 odometer.JPG sep2020 in line meter.JPG sep2020 eyedro.PNG

    Summary costs as of 30 Sep 2020:

    sep2020 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $45.7254 - $43.4017 = $2.3237/km

    Discussion: The insurance for the next 12 months was paid this month.

    Like my TM3, the insurance will ultimately become the largest operating expense on a per km basis.

    The "Purchase" total is larger this month as it includes the Opti-Coat (ceramic) procedure as well as the winter tire/wheel package.

    The "Reg Maint" charge of $98.13 was for the 12 cans of Krown rust spray.
     
    electriceddy likes this.
  4. Still some time to go to reach your goal, thanks for and appreciate the updates...a lot of work involved in this.
     
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  5. navguy12

    navguy12 Well-Known Member

    Cheers. :)

    I'm a data nerd.

    When I talk EV's (and the like) with newbies I never say anything I cannot back up with data.
     
  6. navguy12

    navguy12 Well-Known Member

    Oct 2020 results:

    oct2020 raw data.PNG

    oct2020 real upload data.PNG
    Raw data for Oct 2020:

    oct2020 odometer.JPG oct2020.JPG oct2020 eyedro.PNG

    Summary costs as of 31 Oct 2020:

    oct2020 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $25.1608 - $23.8706 = $1.2902/km
     
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  8. navguy12

    navguy12 Well-Known Member

    Nov 2020 results:

    nov2020 raw data.PNG
    nov2020 real upload data.PNG
    Raw data for Nov 2020:

    nov2020 odometer.JPG nov2020.JPG nov2020 eyedro.PNG

    Summary costs as of 30 Nov 2020:

    nov2020 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $24.2671 - $23.0218 = $1.2453/km

    The Kona sits in the garage as my wife recovers from elective surgery. Normal driving patterns should re-commence mid December.
     
  9. navguy12

    navguy12 Well-Known Member

    Dec 2020 results:

    dec2020 raw data.PNG

    dec2020 real upload data.PNG
    Raw data for Dec 2020:

    dec2020 odometer.JPG
    dec2020 in line meter.JPG

    Summary costs as of 31 Dec 2020:

    dec2020 summary.PNG
    Total operating costs, per km (total costs minus capex costs):

    $20.7437 - $19.6747 = $1.0690/km
     
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  10. navguy12

    navguy12 Well-Known Member

    Jan 2021 results:

    jan2021 raw data.PNG

    jan2021 real upload data.PNG
    Raw data for Jan 2021:

    jan2021 odometer.JPG

    jan2021 in line meter.JPG

    Summary of costs as of 31 Jan 2021:

    jan2021 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $16.1146 - $15.2780 = $0.8366/km
     
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  11. navguy12 likes this.
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  13. The car's "accumulated info" compared with actual AC kWh drawn being at 97% (139/144) does not seem realistic. The best possible OBC efficiency alone is 91% and there are many additional overheads such as running the car's electronics and charging the aux battery.

    For troubleshooting the most accurate intermediate data available is the energy supplied to the battery and that's obtained by reading CEC (from an OBD app) before and after charging. The difference is the actual kWh delivered to the pack. The readings will still be valid even taken some hours before and after the charge duration because the only periodic live load to the pack is aux battery charging and that depletion is minor in comparison to what you're adding.

    I believe the accuracy of the BMS's current and voltage measurements are likely very good because the accuracy of the running SoC is entirely dependent on that, and it's DC. Those values would be integrated in real time by the BMS to add to accumulated kWh.

    I charge at only 1.7 kW so losses will be somewhat higher but typically my battery pack receives 84% of the AC energy delivered. I've verified the AC energy measurement device by comparison with a true RMS DMM on a similar fixed resistive load and they concurred to 99%.

    The car's "accumulated info" should use the same BMS hardware but for current leaving the battery. That would be affected by pack cycle losses which are 2% in my estimation.
     
    Kirk likes this.
  14. navguy12

    navguy12 Well-Known Member

    I think you forgot to add the energy added to the car in locations other than "home" for this month.

    A quick review of the Jan 2021 results:

    jan2021 raw data.PNG

    On 04 Jan 2021, we went for our first test of a high speed, level three charger.

    According to the screen shot of what was dispensed on 04 Jan 2021:

    IMG_0641.JPG

    ...plus what was drawn from the grid for all other times this past month:

    jan2021 in line meter.JPG

    ...gives the total of (18.712 + 144) 162.712 kWh.

    Again, a review of the Jan 2021 data:

    jan2021 real upload data.PNG

    In the above screen shot of my spread sheet, for the month of January, the car odometer based uplift of 139 kWh is derived from 175 Wh/km multiplied by 795.5 km traveled (equals 139.2125 kWh, spreadsheet figures as shown are rounded for clarity).

    Real energy amount drawn from the grid to the meter/dispenser (home plus one DC charger event) is 162.712 kWh.

    So I get a 17% delta this month.

    I don't dispute your observations, however I'm simply tracking two numbers.

    First number: what has the grid "given" to run the car.

    Second number: what does the car say the energy spend actually was to propel it x km.

    And based on my (admittedly very low) total distance numbers of an 18% spread between "grid" and "odometer" numbers, I'm comfortable in telling people who are interested in the efficiency of my wife's Kona "to add about 18% to whatever the trip odometer tells you to figure actual energy usage".
     
  15. Ok, that's fine, I didn't want to spend too much time digging through all those numbers.
     
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  16. navguy12

    navguy12 Well-Known Member

    Feb 2021 results:

    feb2021 raw data.PNG

    feb2021 real upload data.PNG
    Raw data for 2021 (away from home recharge data photo missing):

    feb2021 odometer.JPG

    feb2021 in line meter.JPG
    Summary of costs as of 28 Feb 2021:

    feb2021 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $13.3014 - $12.6064 = $0.6950/km
     
  17. You should really separate your capital costs from your operating costs. Just take a fraction of the capital to represent the amortization amount for the time you own the car to add to your operating cost. That would make your final numbers look a bit more meaningful, esp that final Cost Summary box.
     
  18. navguy12

    navguy12 Well-Known Member

    Right now the cost is, as broken out above, 69.5 cents per km.

    I do not estimate a fraction of the capital because the day the car is disposed of will result in a negative value being entered as a capital cost, specifically the actual selling price of the vehicle to the new owner.

    Of course, at disposal, any disposal costs are captured as line item costs prior to the sale...such as Ontario used vehicle package and safety inspection.

    I’ve been tracking my automotive costs on this fashion since 1997.

    Once a vehicle is disposed of (always private sale, have never traded in) and the spread sheet is locked, it contains the true cost per km with actual depreciation captured at that time...not including opportunity costs of course.
     
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  19. navguy12

    navguy12 Well-Known Member

    Mar 2021 results:

    mar2021 raw data.PNG

    mar2021 real upload data.PNG
    mar2021 in line meter.JPG

    mar2021 odometer.JPG

    Summary of costs as of 31 Mar 2021:

    mar2021 summary.PNG
    Total operating costs, per km (total costs minus capex costs):

    $12.2889 - $11.6442 = $0.6447/km
     
  20. navguy12

    navguy12 Well-Known Member

    Apr 2021 results:

    apr2021 raw data.PNG
    apr2021 real upload data.PNG

    apr2021 odometer.JPG
    apr2021 in line meter.JPG
    Summary of costs as of 30 Apr 2021:

    apr2021 summary.PNG

    Total operating costs, per km (total costs minus capex costs):

    $11.5831 - $10.9739 = $0.6092/km
     
  21. navguy12

    navguy12 Well-Known Member

    May 2021 results:

    may2021 raw data.JPG

    may2021 real upload data.JPG

    may2021 odometer.JPG

    may2021 in line meter.JPG

    Summary costs as of 31 May 2021:

    may2021 summary.JPG

    Total operating costs, per km (total costs minus capex costs):

    $10.5468 - $9.9900 = $0.5568/km
     
  22. navguy12

    navguy12 Well-Known Member

    June 2021 results:

    jun2021 raw data.JPG

    jun2021 real upload data.JPG

    jun2021 odometer.JPG

    jun2021 in line mater.JPG

    Summary costs as of 30 Jun 2021:

    jun2021 summary.JPG

    Total operating costs, per km (total costs minus capex costs):

    $10.0085 - $9.4788 = $0.5297/km

    Discussion:

    Just like my TM3, when the monthly distance driven decreases (compared to other high distance traveled months) the difference between what the car indicates was used for propulsion versus what was actually drawn from the grid increases (compared to other high distance traveled months).

    With only two EVs, the data set is small, but I will assume that the world wide EV fleet acts the same: "phantom" energy use becomes a larger factor with less distance driven.
     
  23. navguy12

    navguy12 Well-Known Member

    July 2021 results:

    jul2021 raw data.JPG

    jul2021 real upload data.JPG

    jul2021 odometer.JPG

    jul2021 in line meter.JPG

    Summary costs as of 31 Jul 2021:

    jul2021 summary.JPG

    Total operating costs, per km (total costs minus capex costs):

    $9.3868 - $8.8731 = $0.5137/km
     
    Lars, KonaDan and electriceddy like this.

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