2014 Honda Accord Hybrid Release Is Approaching

Discussion in 'In the News' started by xcel, Jul 1, 2013.

  1. Luke

    Luke Well-Known Member

    Probably should post this somewhere else?

    I drove today 45 miles and tried to do pure EV driving to see EV only range but on highway speeds it switched to hybrid often even with EV only mode (seems 60 mph or so is threshold?). However first 5 miles at 35-45 mph it showed me range of 14-15 miles (probably less at highway speeds). Total mpg was 62 mpg with 5.4 miles left in EV range. There was some stop & go traffic last 15 minutes or so which increased mpg little bit.
    Drive home I can drain EV fully since last 5 miles or so are not at highway speeds.
  2. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Luke:

    Can you do a Google map from home to work and measure vs. your Odometer/Trip A/B distance? For your next fill, can you do a top off and not reset one of the aFCDs so we can get that offset knocked out as well? After that, it is the speed vs. fuel economy graph ;)

  3. Luke

    Luke Well-Known Member

    It's 46.3 mile and I found odometer was about 0.3 less (but I don't park exactly at that spot so that might be the difference but it's very close. Would odometer be more precise?

    To clarify: do you want me top it off and make a note of current mileage and then at next refill take difference of mileage? Or what's reason not to reset it? Will need some help to do this correctly:).

    For speed vs FE I found it's switching often between multiple modes (EV/HEV/engine only). So will need some help in how to test that properly.

    In 'HEV On' mode it keeps current charge so that's probably the one to use to gauge hybrid mpg. If I turn it off I noticed it still overrides at times at highway speeds. But not constantly so not sure what logic is yet since I barely touch the gas pedal when that happens. Also need to take a look at manual since I see the EV light turn on intermittently at highway speeds. But it's not in sync with the power flow graph so maybe that's the 1st EV battery only?
  4. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Luke:

    Good stuff!!!

    Tomorrow, drive to your road and reset your Trip A or Trip B at that exact point. Not in the garage or drive. From that point, take your normal route and stop at the entry way to the parking lot at work. Record the Trip A or B. Open up Google maps and build that exact route. That is your actual distance and you will use this for your first full tank of fuel to get an actual mpg vs. your aFCD's display.

    When you top off, reset your aFCD(s). Drive the full tank. Now multiply the distance displayed for that tank by the offset to come up with your actual miles traveled. Use that distance/total gallons filled for your actual Fuel Economy. Use that to come up with the actual vs. displayed aFCD offset.

    Now that you have an actual fuel consumption vs. your displayed, head out to a lengthy Interstate with a portable GPS displaying elevation. Low winds and temps above 60 degrees are preferred. The test(s) should be performed later at night when there is little to no traffic to reduce or eliminate traffic side boost.

    While driving along at 60 mph (via your GPS, not the speedometer) with Cruise Control set and your AH's SoC steady at whatever it is, reset your FCD on the fly. When you have traveled at least 10 miles, the final elevation is within 10 ft. of your starting elevation, and SoC is the same as when you reset the aFCD at 60 mph, record your aFCD display.

    Multiply this result by your aFCD display offset for an actual mpg at 60 mph. Do the same in the other direction as well. Now average the two...


  5. Luke

    Luke Well-Known Member

    So I first figure out odometer adjustment factor. So let's say if odometer shows 43 miles and Google shows 44 miles than multiply aFCD with 44/43. Not sure though Google or Bing maps are fully accurate when you make a lot of turns. But GPS navigation system might be more accutate? My Nokia Here app shows distance travelled.

    Regarding emptying tank I can't wait to refuel when it's 100% empty. Unless I'm not commuting then it's easier to make that happen.
    Also not aware of any flat roads here but when I have some time off next month I could try to find something like that.
  6. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Luke:

    The further you can drive for the odometer offset, the more accurate. 44/43 is to rough. 44.2/43.8 would be good enough however.

    You do not need to drive to empty either. Just on your next fill, top off. Drive your normal commute and whatever else. The next time you fill after 500 or so miles, top off again. Now you have the ability come up with an accurate mpg vs. the display.

  7. Luke

    Luke Well-Known Member

    Thanks got it now:). Today I can do the odometer check.

    The 60 mph test may take a while since traffic is almost always busy and need to find stretch of flat road. I could use my hiking Garmin GPS to get elevation history graph to determine if there's stretch on 101 that would be suitable for that (it's pretty hilly except potentially in San Jose area). Also before I test that I guess I want to drain EV first.

    My final mpg yesterday shown was 56.3 mpg (lots of stop & go traffic and last stretch 70+ mph). I'm not able to recharge EV currently at work yet. Still need to look into that.
    Haven't figured yet how to read the 10 bars battery charge. But it seems the first 8 bars are pure EV and last 2 are for hybrid battery (since it shows 0 mile EV at that point). But could be wrong. Aren't there 2 batteries in PHEV?

    EDIT: just checked Google and Bing maps and there's 0.1 mile difference for exact same route (46.2 and 46.3 miles). Less than 1% difference so that shouldn't matter:).
    Last edited: Aug 7, 2013
  8. Luke

    Luke Well-Known Member

    Hi Wayne,

    I checked today odometer and weird thing is that I get 1 mile less and I'm pretty sure the route matches. Is this possible:

    Honda Trip A odometer: 45.3 miles
    Google maps: 46.2 miles
    Bing maps: 46.2 miles
  9. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Luke:

    Yup and this very typical for a Honda ever since the lawsuit a few years back. And it is one of the reasons that their aFCDs usually underreport from actual. Both is which are a good thing.

    Now that you have an underreport of odometer/trip miles vs. actual, when you do your fill calculations, multiply your (miles displayed) * (1.0198) and you have your actual miles traveled.

    You now have 1/3 of the puzzle complete and thanks for going through the motions for us! Or me ;)

  10. Luke

    Luke Well-Known Member

    Great:). That means also I get less miles on my Honda:).

    Tank is still 80% full but will refuel this weekend. Question how to compute mpg since with EV mode mpg you get a mix. I assume you'd be interested in hybrid only mpg and I could drain EV to get pure hybrid mode mpg. However not sure there's such a thing as a EV battery and hybrid mode battery. It's only 1 battery I think now. It shows 10 bars and at 2 bars it shows EV range 0 miles. So 2 bars might be the SOC needed for this test?

    I did do a very brief 70 mph test for about 2 miles on almost flat road and that showed 50 mpg and it was running hybrid only. However too many variables to be sure it's anywhere accurate.
  11. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Luke:

    Did not think of that... Do not charge for the first 200-miles at the beginning of the tank and refuel early. Than you have a solid aFCD offset result.

    That is going to be hard for you to do...

  12. Luke

    Luke Well-Known Member

    My guess is best to drain EV by turning HV off (=EV mode) and wait until EV range goes down to 0 miles. At that point I have 2 bars left out of 10 which I assume is capacity for HV operation. At that point I'll refuel completely. EV range stays at 0.0 miles I found as long as I don't go downhill for a long distance (going downhill for 15-20 minutes or so I found it did charge to about 30%).

    Also I did another 3.5 mile cruise control test at 70 mph on flat road with GPS indicating 70 mpg (speedometer is less than 1% off) and that yielded now 45.9 mpg. Still requires adjustments and need longer distance (ICE only is about 42 mpg). But I'm starting to get feel what I'd get in pure hybrid mode. Driving at 60 mph is not an option here but maybe there's opportunity in the weekend to drive bit slower.

    EDIT: reading manual HV is not quite what I thought it would be. Seems that HV Mode is rather keeping EV charge same. So at 2 bars EV mode is unavailable and keeping HV mode on should keep SOC at same level.

    Electric (EV) mode– At start-up and during low- to mid-speed cruising, the vehicle is propelled by the electric motor, powered solely by
    electricity stored in the High Voltage battery. Not used during aggressive acceleration or while cruising at high speed. When the battery
    charge begins to run low, the vehicle switches to HV mode.

    Hybrid (HV) mode– The vehicle is propelled by electricity supplied by the battery, and also from the generator which is driven by the
    gasoline engine (except during low-speed driving). This mode maintains the High Voltage battery at existing level. You can press the HV
    button to switch from EV to HV mode. Press the HV button again to return to EV mode.

    HV Charge mode– You can press and hold the HV button to charge the High Voltage battery. The engine runs constantly in this
    mode (fuel economy will be reduced). When the electric battery is fully charged, the vehicle switches to HV mode. Press again to return
    to EV mode. During high-speed cruising, the vehicle is directly propelled by the gasoline engine. When driving in HV Charge mode, the engine also
    recharges the High Voltage battery, if its charge level is low.

    (https://ev.owners.honda.com/Accord-...ileName=2014 Accord Plug-In Navigation Manual)
    Last edited: Aug 8, 2013
  13. Luke

    Luke Well-Known Member

    By the way 2nd result of way back home on longer route: 48.2/47.3 = 1.0190
    So that's almost identical (diff from previous reading is less than 0.1 mile).
  14. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    Thanks for doing all this testing , Luke. This is some good stuff !

    This car ( and the upcoming Accord Hybrid) will raise the bar for mid-size(huge) hybrid cars.

    And when the competition is a Toyota hybrid, that's really saying sumthin'.
  15. all_about_the_glide

    all_about_the_glide Well-Known Member

    Thanks...Love the car.
  16. Luke

    Luke Well-Known Member

    Thanks. Unfortunately will take a while to get accurate mpg results. Today I'll refill tank first time and leave EV drained so I can figure out real world mpg. I also checked Garmin elevation profile of my commute but there's not even a 5 mile flat stretch so would have to look elsewhere.

    Yesterday I had EV drained and it was running hybrid system only which got me 43 mpg average driving 30 miles between 65-75 mph (lot of acceleration though since lot of traffic). Last 10 miles were between 30-40 mph and end result was 50 mpg. Still pretty impressive. Certainly ymmv is very true since I noticed the guy driving the car to North California only got 35 mpg (not sure how he achieved that:)).
  17. Luke

    Luke Well-Known Member

    Actually I think I was wrong that EV charge makes a difference because mpg doesn't include eMPG used. So if I drive more EV miles then the amount of gallons used would remain the same since for each 1 EV mile the mpg goes up and odometer evenly as well?

    That said I didn't recharge just in case and got today first refill:

    Indicated mpg: 48.6 mpg
    Odometer: 353.2 mi

    Gas: 6.95 gallons
    Computed mpg = 353.2*1.019 / 6.95 = 51.8 (+7%).

    So looks like it's underestimating mpg by about 7%.
    Next would be to test 60 mph but that will be difficult as I haven't found a long flat road yet and I noticed at constant speed it goes in an out of EV periodically so mpg goes up and down so you need good distance to be sure.
    Last edited: Aug 15, 2013
  18. Mendel Leisk

    Mendel Leisk 2010 Prius (CAN Touring) Staff Member

    Our civic hybrid would under estimate mileage, ie: report worse than calculated. Not by much, maybe 1%. That's commendable, compared to the Toyo Prius BS meter lol.
  19. Luke

    Luke Well-Known Member

    I checked today elevation profiles and the only 10 mile relatively flat road seems to be near Los Banos which is bit far. If I'd go to Yosemite one day I could do some testing but by that time the Hybrid model is probably already available (btw est city mpg went up to 50 mpg).
    That said I have a pretty decent idea what mpg I can get. So far I have consistently hit around 51 mpg at 80% highway in hybrid only mode which is so much better than I expected especially with extra battery weight.

    I'm now able to recharge at work and that gives me 70 mpg each way which is pretty great. Now the only stupid thing I found is that PGE is charging 30 cents per kWh which is more expensive than the gas! I looked into switching to EV rate plan where they only charge 10 cents at night but then during day (2-11pm) they charge 37 cents which is ridiculous. Arguably larger battery I'd be able to offset the higher day rate but still this kind of defeats purpose of promoting EV's.
    Last edited: Aug 21, 2013
  20. Luke

    Luke Well-Known Member

    I just noticed that although capacity is 6.7 kWh a full charge is only 3.7 kWh. So seems its reserving 25%. Is that same with Prius plug-in?

    I still get 14-16 miles with that so I guess no worries just bit confusing.

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