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Re: seat warmer power consumption

Posted: Sun Jan 31, 2016 7:41 pm
by ytrottier
Thank you! Can't beat measurements. I've been taking more careful data using the battery percentages, and I think what was happening was that my regular commute just happened to be right on the edge of losing an extra bar. So yes, the seat heater can push me over the edge, but it's not using a full bar. But I'm still waiting for two identical wind/temp days to do a back-to-back comparison. I will post when I have that.

I'm still curious about the DC-DC converter efficiency if anyone knows that.

Re: seat warmer power consumption

Posted: Mon Feb 01, 2016 5:34 am
by arnis
One bar is 21kWh / 12bars =1 750Wh. That is 1750Wh / 35W = 50h - 50 hours of one seat heater (or 25h of two seat heaters).
Most likely you use seat heater with colder weather. And that has much much more effect on range.

I know that 2011/2012 Leaf had dumb climate control panel that heated water even if climate was not blowing at all.
If it is chilly outside it will use some juice (maybe 100-500Wh) just because it is so dumb. Using any blower will result
in constant consumption. Is it the case? Does Climate consumption graph show any activity if blower is disabled?

Re: seat warmer power consumption

Posted: Mon Feb 01, 2016 6:58 am
by BrockWI
But remember as soon as the car is in ready mode it is consuming somewhere between 200w and 400w with nothing else on, so you have to add any loads to that, not sure what it pulls in acc mode vs on, hopefully a LOT less, but it also isn't running the 12vdc charger all the time then either.

Re: seat warmer power consumption

Posted: Thu Feb 04, 2016 7:51 pm
by ytrottier
I've managed to collect data from three similar days. All these trips were along similar routes, with the same elevation change (+160m), same general direction (westward) and same weight. Climate control was always off for the whole trip.

Code: Select all

Wind   SSW 24        SSW 24      S 24    km/h
Temp     +3           -3          +5     deg C
Speed   70.4          74.1       77.6    km/h average
seat     off          off        high    driver seat only, plus steering wheel.
Dist.   118.8        103.0       107.5   km
start     81           89         99     % charge
end       0            14         25     % charge
delta     81           75         74     % charge
d/chg    1.46         1.37       1.45    km/%charge
It's a 2016 model with a 30kWh battery, not the old 24. Supposing that 0 to 100% is 26kWh, 1.45 km/% works out to around 5.6 km/kWh, which is about what the dashboard computer gives. Energy economy is within 6% among all trips, which is within 3/4 of a bar. But most of that difference was probably just due to the lower temperature of the middle column.

My conclusion is the seat warmer doesn't make a difference. I probably got that impression from the reduced battery efficiency with dropping temperature. (And again, for those who didn't get it the first time, climate control was OFF. The 2016 has a heat pump, not a PTC heater, but it doesn't matter because it was off.

Re: seat warmer power consumption

Posted: Thu Feb 18, 2016 2:14 pm
by arnis
Actually Leafs with heat pumps do have PTC heaters. It is used much less and in above freezing weather almost not used at all.

Like I said 0,035kW each hour is not measurable :)

Re: seat warmer power consumption

Posted: Thu Feb 18, 2016 8:45 pm
by dhanson865
arnis wrote:One bar is 21kWh / 12bars =1 750Wh.
The quote below shows how the bars are anything but even and I hope you'll see that you shouldn't use 1/12 for any sort of math related to them.
I'm not going to worry about duplicates at the cusp, I'm sure you aren't worried about the last tenth of a percent. Oh and there are two kinds of bars

capacity bars
100% to 85% = 12 bars (15%)
85% to 78.75% = 11 bars (6.25%)
78.75% to 72.5% = 10 bars (6.25%)
72.5% to 66.25% = 9 bars (6.25%)
66.25% to 60% = 8 bars (6.25%)
60% to 53.75% = 7 bars (6.25%)
53.75% to 47.5% = 6 bars (6.25%)
47.5% to 41.25% = 5 bars (6.25%)
41.25% to 35% = 4 bars (6.25%)
35% to 28.75% = 3 bars (6.25%)
28.75% to 22.5% = 2 bars (6.25%)
22.5% to 16.25% = 1 bar (6.25%)
16.25% to 0% = 0 bars (16.25%)

charge bars
100% to 91.5% = 12 bars (8.5%)
91.5% to 84% = 11 bars (7.5%)
84% to 77.9% = 10 bars (6.1%)
77.9% to 70.8% = 9 bars (7.1%)
70.8% to 66.2% = 8 bars (4.6%)
66.2% to 58% = 7 bars (8.2%)
58% to 50.9% = 6 bars (7.1%)
50.9% to 43.4% = 5 bars (7.5%)
43.4% to 36.3 = 4 bars (7.1%)
36.3% to 31.3% = 3 bars (5%)
31.3% to 26% = 2 bars (5.3%)
26% to 17.4% = 1 bar (8.6%)*
Low battery
Very low battery

*see range chart and other threads for how dangerously quick you can drop from 1 bar to turtle. Don't rely on expected range at low states of charge.

and note the charge percents I gave were based on a 100% capacity battery all the charge bars get modified if the capacity is below 100%.
and I'd have to link to another thread to document why you shouldn't use 21 kWh and should instead use a higher number but for now I'll let that fraction be.

Re: seat warmer power consumption

Posted: Sat Feb 20, 2016 10:13 am
by ytrottier
Thanks for the information and data! Is there a good place to read consolidated information on range and battery capacity, especially for the newer lizard battery? I'm commuting 210 km/day, in a situation where I have to be very careful about range. I modulate my speed and charging times down to the minute, collect lots of data, and adjust for temperature and wind to routinely arrive at destination with 2-3% charge.

I know the only long term solution is to instal a level 2 charger at home, and I have the hardware, but it may be months before I can arrange installation. (Don't ask. It's complicated.) Until then, I have to rely on smarts, discipline, and the weather getting warmer faster than my battery capacity fades. I've been doing this since November and never gotten the turtle mode, and with an early spring coming I'm optimistic I can make this work until my charger is installed.

Re: seat warmer power consumption

Posted: Tue Nov 29, 2016 6:38 am
by MikeJaneWill
Hello. In my case i use the Wagan IN9438-2 12V Heated Seat Cushion with Lumbar Support. He uses little electric energy, and does not drain the battery as much as his alternate versions. For his Voltage this model warm cool as for me. It is not the best choise but correlates well: the price-quality. :D

Re: seat warmer power consumption

Posted: Wed Aug 23, 2017 12:10 am
by MikeJaneWill
On the nose of winter, and I again get it) :)