most efficient heating in winter, power gauge to battery drain?

Discussion in 'Clarity' started by michael shama, Nov 19, 2018.

To remove this ad click here.

  1. michael shama

    michael shama New Member

    Hi all!
    Long time reader, 1st time poster. Owned my clarity 7 months, 9500 miles. LOVE IT!! (of course many things need to be improved, hopefully via wireless updates). But in the meanwhile, I have several technical questions about power usage. I have a 40+ mile roundtrip commute in the DC area. Summer was no problem, but now I need to squeeze every mile I can in DC area winter. It occurred to me that I am cycling my battery (max fill to “empty” much more frequently than I should, and hopefully that wont rapidly diminish battery capacity). So, in an effort to be most efficient, I have several questions:
    1. Is the power gauge to battery drain linear? I have a hunch its not linear, and not quite logarithmic, but some weird mix. Further confused by the lack of numbers on the gauge.
    2. Does anyone know how much power the heater/seat warmer draws? is it constant? I found this for Tesla which is great! but not sure if the honda is the same (I feel like its way different). Based on this, most efficient heating would be seat warmer, followed by heater at low setting (what matters more, temp or fan speed?)
      1. I guessed this was like a home heater where the temperature doesn’t really matter, as the system is either on or off, but recently have convinced myself temperature does matter more, fan speed matters less?.
    3. I have a feeling that having the seat warmer/heater on while driving 60mph would drain the battery faster than seat warmer/heater on while stopped. Is that true?
    Any details/tips are appreciated. Thanks all!
  2. To remove this ad click here.

  3. Robert_Alabama

    Robert_Alabama Well-Known Member

    Attempted answers:
    1) I have no reason to believe it isn't linear, but I have no real proof of that since the information isn't overly available to view in real time as we drive the car.
    2) I would bet around 100 Watts per seat at full output , but I haven't seen actual numbers. I think it is probably constant and only varied as you change the level of warming. I agree that the seat warmers are the lowest drain on the battery for climate control. I think for the heater setting that the temperature setting being warmer will draw more than the fan speed being faster.
    2.1) I think temperature is very important, fan less so.
    3) I don't believe that the load is any different for seat warmer/heater either with or without the car moving (or going 60 mph).
  4. Atul Thakkar

    Atul Thakkar Active Member

    Have you noticed any difference whether you keep inside air circulation or keep fresh air from out side ON ?
    I thought inside air circulation should be more efficient due to heated air circulated , however I noticed that it fogs the window, so works only some time.
    I noticed that it is better to keep outside air ON rather than putting front defog setting on for glass which will turn ON A/c by default and kill more battery.
  5. su_A_ve

    su_A_ve Active Member

    From what others have said elsewhere, seat warmer is more efficient than heater use.
  6. dnb

    dnb Active Member

    "Econ" mode on will trigger seat warmer (driver only) and heat slower but more efficiently.

    However, your best bet is to pre-condition the car while its still plugged in, that way you'll leave the house / work with a pre-warmed / cooled car and still full battery.
    Richard_arch74 and jorgie393 like this.
  7. To remove this ad click here.

  8. Jason Lalonde

    Jason Lalonde New Member

    I always pre-condition my car now that it's cold while it's plugged in. It does not take long to warm and it's awesome getting in a warm car in the winter (This is becoming one of my favorite features). As the heating element are already at the peak heat I figure that it's more efficient. I also at times will turn off the heat a few minutes before arriving at my destination as the inside of the car will take a while to cool down to the point where it will bother me (I'm slowly acclimatizing myself for when I step out of the vehicle) while also saving energy. I'm not sure how much these things make a difference but I only do them if I know I will go eventually deplete my battery that day. If I'm just making a short trip, then the heat is blasting and the seat warmers are on full. I do wish it had a steering wheel heater.
  9. bpratt

    bpratt Active Member

    Everyone usage of the seat heater or heater is going to vary depending on how you drive your Clarity. Why not do what I did to find out how much my AC effected my driving range. I simply pulled my car out into the hot sun on a 95 Degree day, started the car (ICE not running) and sat there monitoring the EV range. In about 20 minutes, the range had gone down 1 mile so I concluded that using the AC was going to cost me 1/10 mile every 2 minutes or 1 mile in 20 minutes. Now I could easily calculate how long my daily commute took and how much the EV would be effected.
    I'll probably eventually do the same test for the driver seat heater and the heater.
    Randy Stegbauer likes this.
  10. I've thought about doing that as well. Let's see, charge fully, turn on both seat heaters to high and record how fast the EV milage goes down. Finally, reset my Kill-a-Watt and recharge, noting the kWh used to recharge fully. I'll do that this week and report back.

    That said, I did this for 10 minutes in my car one day a few weeks ago and noticed that the milage went *UP* after five minutes with the seat warmers on. I think it went from 31.1 to 31.2 and then again to 31.3 after five minutes (or so) each. When I got back into the car after doing my shopping, it reported 31.5. Odd. Any explanations?

Share This Page