Honda Clarity, the Volt Challenger

Discussion in 'Clarity' started by bwilson4web, Dec 6, 2017.

  1. Tiralc

    Tiralc Active Member

    Agree, liquid cooled, antifreeze. Only correction to the web review was that there appear to be two separate cooling systems inverter and battery, not one single system. (from the owner's manual, just scratching the surface so far, it's some 587 pages of good info).

    Last edited: Dec 16, 2017
  2. Tiralc

    Tiralc Active Member

    Fair question on visibility, not sure I can answer directly after a few years. I remember going from a Subaru Outback visibility to the Gen 1 Volt was a severe shock. But, I got used to it, and came to use the side mirrors far more often. I see what you mean about the see through part that was Gen 1, not Gen 2, but honestly Gen 2 felt about the same to me. I feel like I'm sitting a bit higher now in somewhat larger windows. The pillars might be a bit narrower too, and/or their placement seems better for visibility. The angled side mirrors (two different pitches on each mirror) help too.

    I completely agree with jdonalds on the little rear window through the trunk, I'm not sure how useful it will be, and it probably was not needed.

    I've only tried pre-heat plugged-into L2 so far. I will try to check on the previous climate question. The Clarity has "auto". I think you are saying it would be counter productive if A/C from the day before came on for a chilly morning, makes perfect sense. We are all just learning and sharing experiences. There is a lot to learn, more experiences and views are very helpful.

    The only thing I find a bit disturbing is nothing from this forum, but some of the web reviews and blog posts which are conveying incorrect information, mostly about regen.
    Last edited: Dec 16, 2017
  3. jdonalds

    jdonalds Well-Known Member

    Drive redults.

    Today we took a 183.5 mile trip on a mostly straight freeway with a slight elevation drop (perhaps 200 feet). The car tells me the car got 60.6mpg.

    We started with a full battery and full tank of gas (yes ALL 7 gallons!).

    We drove in Econ mode for about 43 miles at which time the ICE started. I pushed the Charge button to recharge the battery.

    Checking the instantaneous mpg it would read about 40 (just a bar graph no digital readout) until I pushed the HV button to put it in charge mode at which time it would drop to about 30mpg.

    The recharge was much faster than I thought it would be. It wasn't one mile of EV range for one mile traveled with the ICE but it wasn't far off. The EV range was up to 25 miles after about 30 minutes.

    At that point we switched back to Econ, drove until the EV range hit zero, then recharged again. By this time we finished our drive in Econ and arrived at our destination with about 10 miles of EV charge remaining.

    i figure without the recharge cycles we would have gotten about 52 mpg so this was a win.

    We will continue our test on the way home tomorrow.
    Atul Thakkar and FrameFlipper like this.
  4. ether100

    ether100 New Member

    FYI -- The 2018 Accord's remote start feature works toward a temperature of 72 F according to the video below. Maybe the Clarity is the same.

  5. If you mean that by charging and discharging your battery you saved gas then you are almost certainly wrong.
  6. Johngalt6146

    Johngalt6146 Active Member

    Thank you very much for your detailed comments! You are doing a good deed.
  7. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    I dunno, I'd like to see some real-world testing of that theory. With electric-powered miles being about 3-3.5 x as energy efficient as gas-powered miles, it may well be they would save some gas overall that way.

    But altho I can see a reason for repeatedly using the gas generator to charge the battery on a middling-distance trip as part of testing out a new car to see what it can do, I think it would be a very bad idea to do that on a regular basis. That would wear out the battery pack with unnecessary cycling.

    Using the gasmobile mode to travel long distances on the highway, saving the battery's energy for in-town driving, is a good strategy, because EVs are far more efficient than gasmobiles in stop-and-go driving. But using the gas motor to charge up the battery pack... frankly, I can't think of any time that would be a good idea**. Charging using electricity from the wall is <i>so</i> much more energy efficient than using the gas motor for charging.

    **Well, one exception: If you were driving into a district where tailpipe emissions were restricted (as it soon will be in Central London), and you'd be facing a fine or a fee for burning gas in that district, then I suppose it would make sense to charge up the battery even if you had to use the gas motor to do so.
  8. The efficiency of gas doesn't come into play here. I'd estimate the round trip efficiency of engine to electricity to motor as 70%. A quick Google search turned up a figure of 41% to 69% for a home energy system. That means you have to be driving at a speed where your gas engine is less that 70% as efficient as it is when charging. Now, at idle I agree that would be true, but it's not easy to even get the engine to run at idle. At normal speeds I doubt you will save anything.
  9. bwilson4web

    bwilson4web Well-Known Member Subscriber

    Let me suggest this protocol I follow with our Prius Prime:
    1. Use EV to reach highway speed.
    2. Reset trip meter.
    3. Enable HV mode so the engine warms up while at speed, highest warm-up MPG.
    4. When low fuel warning comes on, use CHARGE mode to top off battery, your reserve.
    5. Run out of gas and note MPG from trip meter.
    6. EV to next gas station.
    Bob Wilson
    Domenick likes this.
  10. Pushmi-Pullyu

    Pushmi-Pullyu Well-Known Member

    I think you have chosen the wrong factors to compare. What should be compared is the amount of extra fuel the gas motor uses when charging the battery -- not when idling, but when traveling down the road -- and how many miles that amount of charge will take the car, versus how much gas the car uses and how far it can go when in extended range/gasmobile mode without charging the battery.

    Now, I agree that if you just sit still and idle the car merely to charge the battery, that's probably going to yield very poor energy efficiency. Furthermore, common sense and the Laws of Thermodynamics suggest that using the gas motor to do no useful work other than charging the battery pack can't possibly be as efficient as using the gas motor to push the car down the highway, because... physics. However, because we're dealing with engineering here and not pure physics, I won't claim this as fact... only as very likely.

    Or to put it bluntly, it would be stupid to run the gas motor for no other purpose than charging the battery.
  11. I don't think I have.
    The point about idling is that is a case where charging the battery with the engine makes sense, so much so that you are almost forced to do it.
    You make that sound like a complicated comparison. It isn't. You should only switch in and out of charging if the engine would be inefficient. That generally happens automatically.
    No one has suggested that is a good idea.
    It is better when you are avoiding running the engine inefficiently, like idling. Otherwise, I am suggesting, it generally isn't.
  12. jdonalds

    jdonalds Well-Known Member

    Here is the end result from our weekend trip while using as much Recharge as possible.

    We traveled a total of 374.3 miles. We continued to drain the battery running in EV mode, followed by a Recharge using the ICE. I didn't count but I think we recharged 5 or 6 times total. The trip meter said we achieved 46.4 mpg for the whole trip. That's better than the EPA estimates, but the car will never hit the EPA estimates when driving 75 mph. I haven't filled the gas tank yet so I can't compute the mileage that way.

    I figure if we did the same trip (my wife will try this in a couple of weeks) just starting out with a full charge and running 47 miles, then the rest on the ICE at 75 mph for almost the entire trip we would have gotten something like 327.3 miles at 37 mpg = 8.85 gallons. Applying that amount of gas for the entire 374.3 miles we would have averaged 42.29 mpg. The truth will come when I fill the gas tank tomorrow.

    So there was a 4 mpg improvement using those calculations. It really depends on the amount of miles traveled and how many EV cycles there are for that distance. The recharge cycle kicks itself off when it reaches about 25 miles EV charge.

    A more ideal trip might be starting out with a full battery and...
    47 miles EV
    40 miles ICE
    25 miles EV

    That's a total of 112 miles with a single gallon of gas, so 112 mpg using recharge.

    Take the same trip with just the ICE
    47 miles EV
    65 miles ICE

    That's a total of 112 miles with about 1.625 gallons of gas for the 65 miles on ICE, so 68.92 mpg with no recharge.

    There are many variations of course.
    Last edited: Dec 18, 2017
  13. jdonalds

    jdonalds Well-Known Member

    Here are a few observations from our trip this weekend concerning the four drive modes.

    Other than Sport which I didn't try and am not likely to use (we never used the power mode in the Prius). I don't believe there is any such thing as pure ICE mode. When the car is put into HV mode it is really in hybrid mode, alternating between the ICE and EV all the time. Unlike the Prius (2015 model) the hybrid mode will switch to EV even at 75 mpg. So when I put the car in HV mode I was, at first, surprised to see the car happily going along in just EV mode some of the time.

    When in ICE + Recharge mode the ICE does stay on all the time and the EV mode is 100% off.

    I really wish the car has a digital instantaneous mpg readout but it doesn't, or at least I haven't been able to find it. But there is one graph that attempts to show instantaneous mpg, leaving the driver to guess what the value is. It looked to me like the car was averaging about 37 mpg at 75 mph when in HV mode and the ICE was running. Switching to HV+Recharge it looked like the mpg dropped to something around 27 mpg.

    Econ isn't actually EV mode. Econ can be switched on any time. I don't know if it has any effect when in Sport mode but it apparently continues it's quest to improve mpg when in HV mode or not.

    To go full electric one switches HV off. So really it is the HV switch that controls everything. I had assumed that the Econ button turned on EV - wrong.

    HV On means hybrid mode. Of course that's what HV means I know.
    HV On with Recharge means ICE mode
    HV Off with Econ Off means EV mode but the ICE may kick on (I suppose)
    HV Off with Econ On is your best shot at EV mode. And in our own use of the car it really is EV mode with no ICE unless you really jam down on the accelerator. We went for nearly two weeks without using a drop of gas, including city and highway driving.

    The car attempts to indicate how many miles of EV remain, and how many miles of HV remain. We saw some pretty strange HV readings. At one point the HV range read over 500 miles. At that time we had achieved 50 mpg average and it looked like we had used perhaps a gallon or two of gas. So if the computer was using those figures of 50 mpg and the remaining 5 or 6 gallons of gas in the tank it would have made more sense to show an HV range of 250 to 300 miles (which I wouldn't believe either). How it came up with over 500 mile is a mystery to us.
  14. jdonalds

    jdonalds Well-Known Member

    This is the first car we've had with any drive assists like Honda Sensing. Here are my observations. You may have much more experience and a different take, but it's sometimes interesting to hear a newbies feedback. I'm the newbie.

    ACC - Adaptive Cruise Control
    Pros: It's great. I was very much looking forward to ACC when we bought the car. The trip we took this weekend is a perfect application. A divided road with two lanes on each side; the road being nearly straight and pretty much flat. When we approached a slower moving car the Clarity would adapt. That just took the whole job of either clicking the cruise control to slow down, or shutting the cruise off and working the pedals. It was just great and it worked quite well. The Clarity gives four distance categories. I felt the closest distance selection wasn't tight enough for me.

    Cons: If I was in the fast lane and wanted to pull over to let someone pass I might pull into the slow lane with a car ahead but the distance to that car was less than the ACC was comfortable with. I didn't think it was too tight myself. The Clarity was much too aggressive, slowing or actually applying the brakes. At one point I pulled over in front of a truck with what I thought was an ample distance between me and the truck. But with a car ahead of me in the slow lane the Clarity applied the brakes and really pissed the truck driver off. I think the Clarity could be smarter about this and ease back rather than being so aggressive.

    Then when I'm in the slow lane, going 63 miles an hour behind a truck (ACC speed set to 75 mph) and I pull over into the fast lane the Clarity is painfully slow at accelerating up to 75 mph. I found I had to apply the accelerator to smoothly move into the fast lane merging with the traffic in that lane. The good news is applying the accelerator doesn't interrupt the ACC settings. My guess is the Clarity is trying to maximize mpg but it doesn't make for good driving habits in typical conditions.

    On a scale of 1-10 I would rate the Clarity ACC an 8.

    LSF - Low Speed Follow
    Pros: Very cool. You're in heavy traffic, stop and go traffic. Set the car in ACC mode and not only will the car follow the car ahead matching it's speed (up to your cruise setting) but if the car ahead stops, say at a red light, so will the Clarity. We tested it and it works great! After a stop, completed by the LSF, the car will remember the prior set speed and attempt to regain that speed.

    Cons: When the car ahead starts up again I must either touch the accelerator or the Resume button on the steering wheel to make the car go again. The Clarity will otherwise just sit there. I can understand this limitation.

    On a scale of 1-10 I would rate the LSF a 10.

    LKAS - Lane Keep Assist System
    Pros: Someone said having a plug-in hybrid was frustrating because it was just a taste of a real full electric car. I feel the same way about LKAS. Yes the Clarity does Assist but I want more. On a straight road it will keep the car in the lane. It demands keeping my hands on the steering wheel, and actually applying some force. Ultimately it does what it is designed to do - Assist. I am always diligent about looking ahead when driving. Those times when I reach for something and look away I find that I have a tendency to drift right in the lane. The LKAS prevents that. I do fear that I will become a bit too dependent on it though and develop habits of looking away from straight ahead. In that case the LKAS would be a determent.

    1) Straight road fine. Put a slight curve in the road and LKAS has a slim chance of staying in the lane (at 75 mph in our experience). In those cases I must take over and steer through the turn. I'm not talking about a tight turn at all. These are gradual turns that are no challenge to navigate at 75 mph. You can forget the car steering on a curvy country road.
    2) The Clarity wanders from the left side of the lane to the right side, all the time. It's annoying.
    3) I didn't know it but when I pass an 18-wheeler I have a tendency to shift over a bit to the left as I pass the truck. The LKAS wants to stay in the center and that made me a bit uncomfortable. So I would steer toward the left a bit, fighting the LKAS which was insistent about staying in the center.
    4) The LKAS isn't smart enough. When in the slow lane and passing by an off ramp or on ramp to the freeway the LKAS would try to stay in the center using the left lane marker on that side but seeing the white strip splitting off toward the exit as the right side. The car would veer to the right momentarily, then recenter itself when the right side lane marker reappeared. Same on the on ramp but less of a motion. It seems like the car needs to look further ahead and to be smart about freeway exits.

    On a scale of 1-10 I would rate the Clarity LKAS a 4.

    LDM - Lane Departure Mitigation
    Pros: Great. I wouldn't want any system that would make a sound to warn me if I'm leaving a lane. The Clarity shakes the steering wheel; it's quite noticeable, and welcome. It also flashes a warning in the instrument cluster.

    Cons: The Mitigation system is supposed to help, "in addition to a visual alert, applies steering torque." Whatever it does to help it isn't enough. While I was testing the Clarity's ability to navigate through curves in the freeway the car would sometimes leave the lane and the LDM would go off. At no time did I feel the LDM was helping me correct. It may have been trying but it was far from enough help to notice.

    On a scale of 1-10 I would rate the Clarity LDM a 7

    CMBS - Collision Mitigation Braking System
    Pros: One time the car applied heavy braking was I believe due to the ACC. But it would break quite substantially in that case. The other time was when I was trying the LSF - Low Speed Follow system. In both cases the car proved it was smart about braking. I trust the CMBS would also work but fortunately we didn't have to try it out.

    Cons: What a disappointment that the CMBS says, "It does not prevent a collision nor stop the vehicle automatically." Why? I don't get it. The LSF will stop the car completely. If it didn't we would have crashed into the car in front which had fully stopped. This seems dumb to me. Must be due to some sort of liability issue. Okay I get they can't prevent a collision, but at least brake to a stop if needed.

    On a scale of 1-10 I would rate the CMBS a 6

    Break Hold
    One more cool thing we haven't fully tested is the Break Hold. We did try it out. It's a cool feature. When stopped for a long time in Drive, say at a red light, normally I'd have to keep pressing down on the brake pedal to keep the car from moving forward. Just push the Break Hold button on the shift console and the car holds the brakes on for me. When I want to move forward I just press on the accelerator. Works like a champ. I am just a little concerned that I might bump the accelerator and crash into the car ahead too easily though.

    The thing is if I'm in stop and go traffic I need to move forward one car length, then stop again. Break Hold handles this just fine. Again the Break Hold would take over - no need to push the Break Hold button again.

    On a scale of 1-10 I would rate the CMBS a 9
    Domenick likes this.
  15. Tiralc

    Tiralc Active Member

    Similar, but at least some differences. For example, Clarity remote climate control runs for 30 minutes. The iphone app shows the actual interior temperature when pre-conditioning. I ran it from 11 am to 11:30 am, says 75 F now. I don't remember what I left it set to last drive.

    Another thing I need to verify is that the engine will not come on when plugged in (in the garage). So far it has not. The Volt had a vehicle setting that said don't run ICE while the vehicle is plugged in.
    Last edited: Dec 18, 2017
  16. Tiralc

    Tiralc Active Member

    Nice review! Thanks for taking the time to post so many details.

    A couple of very minor differences, I did not see the back and forth drift with LKAS in my first long highway drive home, but I have not tried it since. I agree that LKAS and like systems may be problematic for distracted driving incidents (I still enjoy automated systems though).

    I find the gap settings (following distance) fine for ACC, however most of my driving is away from metro areas where highway driving is relatively light. I am able to use 3 to 4 interval bars most of the time, dropping down as I approach cities (very similar to Volt, except Volt has 3 gap settings). A lot of the time, when traffic builds, I just drop out of ACC.

    Sport mode regen 4 is my staple now, but only because so far it is the only way to keep the higher level regen locked on for one-pedal driving. I might go back to normal or eco, but not sure I want to be having to constantly toggle the regen selectors every time I stop, not sure yet. I know you don't have to, but I like the more aggressive regen when stopping, maybe just habit now. Of course where possible, it is more efficient to gradually slow with no intervention beyond the regular gentle regen.
    Last edited: Dec 18, 2017
  17. Johngalt6146

    Johngalt6146 Active Member

    I really enjoy the detailed technical discussion underway above. Since I can't contribute much to that, here are a novice's impressions of my test drive today:

    Positives: Very Impressive overall. Plenty of power at low speed and no problem in getting from 30-65 quite promptly. When I floored it, the ICE came on with a roar. Its actually not a bad sound - like an afterburner. I could not feel any mechanical transient. Extremely quiet in normal driving. There are a lot of safety and electronic features for the (post rebate) price.

    So - So: Styling leaves much to be desired. The interior tan with dark brown color scheme leaves me cold. I wish they had left it all tan.

    Item of Concern for more study: The car is very wide (73.9" without mirrors), and the mirrors make it even wider. I will need to research to see how difficult it will be to get into my garage.

    Other: The dealer had it blinged out with $1095 of local extras including pinstripes and Nitrogen in the tires. I pointed out that I prefer a 78% Nitrogen blend unless the other is free.

    Final Lament: I know I'm being non-analytic (even though I'm an E.E.), but why can't electric cars be stylish or sporty?

    Domenick likes this.
  18. jdonalds

    jdonalds Well-Known Member

    I filled the gas tank today so can compute the trip average based on real data. Final figures based on actual gas used... We traveled 374.3 miles using 8.838 gallons of gas for a result of 42.35 mpg. So based on these figures it doesn't seem worth the effort to use recharging on the road. I can't imagine much better conditions than we had this past weekend, to test out the recharge feature. We won't bother in the future.

    Still it will be interesting to see what the results will be in a few weeks when my wife makes the same trip, not using recharge.
  19. JyChevyVolt

    JyChevyVolt Active Member

    I will guarantee a better mpg by not using recharge.
  20. Johngalt6146

    Johngalt6146 Active Member

    Mr. JDonalds: What is the total width of the Clarity from mirror tip to mirror tip (with the mirrors NOT folded)? I know the car width (w/o mirrors) is 73.9 inches, but I cant get a straight answer from Honda about the width including the mirrors. Thanks much!!!

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