HV Only Gas Mileage

Discussion in 'Clarity' started by David Towle, Dec 15, 2018.

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  1. Linkmodo

    Linkmodo Member

    Makes sense for areas where there are a lot of hills... Where I live it's flat as it can be
     
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  3. neal adkins

    neal adkins Active Member

    There's a down grade of about 14 miles that increases bars. Probably from 2 bars to about 50 percent if i use hv charge mode, to the best of my memory. I will check it closer next time i go that way. Average speed is around 65 mph.
     
  4. Clarity_Newbie

    Clarity_Newbie Active Member

    MNSteve

    Yes I see gain daily...plus...corresponding decrease. Can't mess with physics...what goes down must eventually go up all things being equal. lol

    Hope this helps.
     
  5. David Towle

    David Towle Well-Known Member

    But there's always significant losses in the process. If there wasn't, the mpg penalty for driving in hills would be close to negligible.

    So I guess no one thinks the 33-38 mpg runs I recorded is out of the normal range?
     
    JustAnotherPoorDriver likes this.
  6. Clarity_Newbie

    Clarity_Newbie Active Member

    Fully agree...thats why I also state "...corresponding decrease..."

    33-38 seems low to me but then again my temps have barely dipped below 40 and I drive conservatively.

    I will do one more test when a cold streak appears to check mileage then. Hopefully January.

    Hope this helps.
     
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  8. David Towle

    David Towle Well-Known Member

    That's what bugs me, I am a very conservative driver so I was hoping for better. I always get over 100,000 miles out of a set of brakes with normal cars.
     
  9. jdonalds

    jdonalds Well-Known Member

    I don't think 33-38 is normal mpg for the Clarity. The only way I see less than 40 is if I hot rod around.
     
  10. Clarity_Newbie

    Clarity_Newbie Active Member

    I can sense your concern which is why I am going to run a test when it gets super cold here for a few days. Trying to help you figure it out.

    I have been fortunate on brakes as well...80k plus on all vehicles except one Subaru with horrendous rotors...the slick service rep tried to tell me all Subaru's got 20k on brake pads and rotors...we tussled a little but I got it fixed (ie) rotors changed out for proper ones. Gotta stand your ground when BS is BS.

    Oh, by the way...after rotors got changed...my next set of brake pads were at 50k plus when I donated the car prior to getting the Clarity. Gotta love it.

    Keep grinding.
     
    David Towle likes this.
  11. David Towle

    David Towle Well-Known Member

    Today when I went to drive the car after it sat about 4 hours, pressed the on button, and noticed a strange noise. Got out and found the two electric fans were running for 10 seconds, then going off for 10 seconds, over and over. Hmmmm.
     
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  13. AlAl

    AlAl Active Member

    Were you running climate? This car is pretty noisy in EV mode too. Lots of squeals and whines while in motion; figure it's just inverter and motor noise
     
  14. David Towle

    David Towle Well-Known Member

    No I never use that, have a garage.
     
  15. David Towle

    David Towle Well-Known Member

    Did another pair of runs similar to my last 2 weeks ago.

    Run 1: Ct shore to Okemo VT again. 30s and 40s temp, wet roads. Speed average 73 mph, battery full at start. Since I only got 33 mpg last time I tried not using the cruise control but kept the power smooth and mostly between about 10% and 60% on the meter by speeding up a little on downhills and slowing down on uphills. Of course on long downhills it went into coast. This kept the gear icon on about 90% of the time. Result 29.5 mpg, terrible. The good thing though is I guess it shows the car's power mode decision making is OK and better than me keeping it mostly in gear.

    Run 2 return: Since the cruise control did not seem to be the problem I kept it in cruise, but used the steering wheel set speed adjustment to keep it from suddenly accelerating or braking. Example before I pulled into the left lane from riding behind a slower car I set the speed just 2 mph above the slower car, then waited for a downhill to toggle back to 73. Also I used the 14 miles of battery range left for the downhill on local roads before getting on the highway. Result 43 mpg, much better (37 last time), especially since it did not include the slow downhill on local roads like last time. Will try using this cruise control method both directions next time.

    Other conclusions: a) The gas tank is too damn small. b) If it wasn't for the under $20k net price this car would definitely be the wrong choice for me. The Accord hybrid due to lighter weight and bigger engine would make more sense with my extensive highway driving. But at the price I'm still happy.
     
  16. Dan Albrich

    Dan Albrich Well-Known Member

    As mentioned my clarity may not have electric range of others, and I am prone to hitting angry bees sound at regular and predictable intervals (anytime electric range is zero). I drive a long flat stretch of interstate 5 about once a month. Not a lot of curves or anything. I tend to drive between 70-80mph on the freeway if there's not a lot of other folks on the road-- but slow down in traffic of course. I measure mileage only actual and ignore what the car says. i.e. Start from full, hit the trip meter. Return to home, fill tank. Divide the total number of miles by gallons of gas purchased. Finish full again. I've done this repeatedly. I always get something above 40mpg. Typically 41mpg. I even got 41mpg after using long HV push after running electric range to zero. Can't explain that, but I did.

    Now I am likely skewing my numbers with electric to some degree-- and I have at times gone EV only for the last 10-20 miles if I remember to do so-- but some trips I forget and still get good mileage.

    -Dan
     
  17. jray19

    jray19 Member

    Here is my observations from a 805 mile trip over several days about 30 EV miles included. Started with full tank of gas and nearly full charge ended with full tank of gas and no EV range remaining. Car loaded with about 400lb of humans and 150lb of gear (550lb total). Generally heat set to 68 as I figured it was almost free since ICE was running.

    Actual MPG 39.93 mpg calculated 805 miles/20.159 gallons of fuel
    GOM trip computer calculated 44.6 mpg

    Details
    Leg 1 EV nearly full 173 miles 3.732 gals of gas = 46.35 mpg. Temps were in the Mid 40's speed was in the 60-70 mph on the highway terrain level (Chicagoland to South Haven MI).
    Leg 2 EV nearly full 190 miles 4.939 gals of gas = 38.47 mpg. Temps around 40 speed was 70-80 mph on the highway some terrain (South Haven to Traverse City MI). Note when speed was in upper 70's the engine was really humming when on level or up hill, much more so than in the low 70's.
    Leg 3 EV down to 8 miles (4 bars) 244 miles 6.238 gal of gas = 39.12. Temps in mid 20's speed around 70 mph on the highway some terrain (Traverse City MI to Kalamazoo MI).
    Leg 4 EV range 0 - (two bars) 198 miles 5.250 gals of gas = 37.71 mpg. Temps were 35 speed was 70 mph for about 130 miles and 65 mph of about 60 miles terrain was level (Kalamazoo MI to Chicagoland). Did notice the GOM estimate of mpg was in the 38-39 range at 70 mph and got to the low 40's when I dropped down to 65.

    Notes:
    - It's hard to preserve EV charge as every time you stop and turn off/on car and reset HV mode it seems to want to loose a little before it settles into it's new level
    - Speed saps mpg. 60-65 mph looks to me will beat the projected 40 mpg rating while 70 seems to yield about 40 mpg
    - No challenges going 80 mph but it does make that little engine work pretty hard compared to slightly lower speeds
    - Seems like having some charge above 2 bars has a positive impact on mpg.

    Please comment.
     
  18. David Towle

    David Towle Well-Known Member

    Great information and pretty compatible with what I found, thanks.
    I have found I get about 35 miles of winter range on the batteries alone at highway speeds, so shouldn't you be deducting that from your mileage total? Therefore (805-35)/20.159 = 38.2
     
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  19. Jordan

    Jordan Member

    I just did all HV driving on a 400 Mile road trip, no hills or anything and got 38mpg. I was very disappointed because usually I've gotten 45 or so. My friend who has a BEV told me that it's very possible that my car would experience lower MPG in cold weather (it was in the low 30s) because it's not a true combustion engine but more like a generator because it still had to use the electricity to power the motor and we know it doesn't do well in cold climates. Anyway, I'm definitely not an expert, but it makes sense (and made me feel better about my lower MPG, still amazing though for a 4000 lb car)
     
  20. ukon

    ukon Member

    I did short trip of 120 miles but interesting observations.
    I went from San Francisco to santa cruz via CA 17 and back to San Francisco via CA-1 coastal mountain highway.
    In First leg there is one 200-2000ft climb followed by going down.
    second leg has two 800-1200 ft climbs and going down by same and several 300ft changes.
    Speed is in 60-65. My mpg was ~48 based on my observations after next refuel. The trip computer showed 51.7 For that trip.

    Something of interest: At 65, 200-2000 ft climb took off 3-4 miles of range. I gained that back downhill if I used regen paddles carefully. On CA_1 when I was just driving using brakes I gained back 75-85% of lost miles.
    Based on this if I were to drive to Tahoe at 7000ft, steady climb, I will keep atleast 70-80% charge in winter to keep my drive pleasant.
     
  21. Walt R

    Walt R Active Member

    This topic seems an appropriate place to note my experiences last week on a road trip, 420 miles each way. Location was NY and Pennsylvania.

    On the way north, temperatures in the low 40s, I saw the behavior I'd previously seen in NJ where in HV mode the engine still shuts off fairly frequently, about 20% of the time and on every little downgrade. Gas mileage is around 42 mpg based on tracking the miles I drive in HV - dash display shows the average as 46-47.

    On the way south I started with temperature about 29 degrees and the car was parked outside (but plugged in). I noticed that the gas engine was never turning off, even when the flow display was in light regen and not pulling any power from it. The first time I saw the engine turn off was when the temperature had risen to 37 degrees (this was over 2 hours after starting). It started turning off regularly when the temperature rose to 41 degrees. Gas mileage on this leg was around 38 mpg (still with the in-car display showing about 10% higher).

    So I have a theory that the gas engine doesn't shut off below about 2 degrees Celsius (37 F) - probably to maintain its own temperature, but cabin heating could be a factor (I tried switching into Econ but it had no effect). 41 F is 5 Celsius and I saw more expected willingness to shut off above that temperature. Without the periods of "free" distance gained with the engine off, gas mileage suffered. These figures are from mostly driving 70-72 mph.

    Do others have similar observations to report? Looking at the geographic regions of those giving experiences above, it seems consistent that those getting poor mileage are in currently cold areas, and those with nice high numbers are describing mild areas. If you keep a close eye on when the engine shuts down in HV, I'd like to know if others have seen the same result.
     
  22. David Towle

    David Towle Well-Known Member

    I think you are saying the engine was on even though on the display there were no arrows going from the engine to the battery or wheels? And you determined this from hearing the engine?

    On the highway I always have the stereo blasting so if that happened I easily could have missed it. I will turn it down and check more closely my next ski trip.
     
  23. Clarity_Newbie

    Clarity_Newbie Active Member

    David Towle

    Pink Floyd? lol

    Haven't forgot about the HV mpg when its is cold...just haven't experienced much yet. We usually get a spell of freezing daytime temps in January to early February. I'll keep you posted.
     

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