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Re: 62kwh Leaf Plus Efficiency Posting

Posted: Sun Nov 10, 2019 3:35 pm
by dmacarthur
Sorry, meant to say "include" external electrical draws, because my miles/KWH drops significantly at night, in the cold, and with winter tires. I would just like to ba able to see the extra drain in real time: how much, exactly, is the heat element or the headlights using?

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Sun Nov 10, 2019 4:03 pm
by WetEV
dmacarthur wrote:
Sun Nov 10, 2019 3:35 pm
Sorry, meant to say "include" external electrical draws, because my miles/KWH drops significantly at night, in the cold, and with winter tires. I would just like to ba able to see the extra drain in real time: how much, exactly, is the heat element or the headlights using?
Drive train is using multiple kW. Headlights are using less than a hundred watts. At 60 MPH, less than a 1% error in measuring the drive train power would be the headlight power. There are no meters measuring this, so either use an estimate or you need to add instrumentation to the car.

Heat element is larger, and can have a noticeable impact.

Other things you can't measure, like increased drag from thicker air, stiffer grease, and such, and factors such as different driving behavior also have significant impacts.

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Sun Nov 10, 2019 6:40 pm
by dmacarthur
I have yet to find any real info on the current draw of the heater element- this model does not have the heat pump so it could be similar to a toaster, or 1500 watts or so, at least while warming up. any ideas? I have asked the dealer for this info.... And my old BMWs had single 100 watt halogen headlights, the Leaf has 2 and they are brighter than the BMW, seems like it is going to be several hundred anyway.... over a period of three hours that could knock a few miles off the range.

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Sun Nov 10, 2019 7:23 pm
by LeftieBiker
The heat pump has a variable draw, from about 500 watts to, IIRC, 3kw. If it isn't that high it's 1.5kw. It's hard to determine exactly, because the PTC heater runs as well when the heat is started.

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Sun Nov 10, 2019 9:54 pm
by GerryAZ
Halogen headlights are 60 watts each (120 watts total). Resistance heater is 5 kW (5,000 watts) maximum, but draws less at moderate temperatures with fan on lower speed. Traction motor is 160 kW maximum so headlight use is negligible compared to heater and traction motor.

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Fri Nov 15, 2019 11:35 am
by Birillo
DaveinOlyWA wrote:
Tue Nov 05, 2019 7:16 am
Birillo wrote:
Fri Oct 11, 2019 7:40 pm
Hi, new to this forum, just doing some pre-reading before my probable Leaf purchase. Currently I have a Volt but I suffer psychological harm every time the ICE kicks in.
I've seen it proposed that lower acceleration getting up to highway speed will improve efficiency. From an kinetic energy perspective it should not matter. Is there some inefficiency in energy used when there is a higher power draw from the battery?
Gentler acceleration will reduce degradation of the pack. We have a LEAFer who has 135,000 miles on his 2015 and LESS than halfway to losing his first capacity bar. He shuns the freeway to take country roads with speed limits of 50-55 mph. He charges to 100% and QC's twice daily to make his commute.

There is a higher resistance factor for higher power but from what I can tell, its pretty negligible. DK how regen works in Volt but I drive in B mode which is high regen and try to anticipate traffic and usually never touch my brakes unless I come to a full stop.
SageBrush wrote:
Mon Nov 04, 2019 8:47 pm
Birillo wrote:
Fri Oct 11, 2019 7:40 pm
Is there some inefficiency in energy used when there is a higher power draw from the battery?
.
Yes, but it is a very minor contribution to the overall result

City: reduce brake use
Highway: reduce speed
Thanks for the responses. Sounds like there is no real efficiency gain from lowering acceleration, although there are other advantages.
I bought my Leaf plus a few weeks ago and so far very happy with it. Impressed my buddies with a golf/road trip with 3 guys, 3 sets of clubs and 3 pull carts!

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Fri Nov 15, 2019 12:02 pm
by jlv
Birillo wrote:
Fri Nov 15, 2019 11:35 am
Sounds like there is no real efficiency gain from lowering acceleration, although there are other advantages.
I'm not sure where you get that conclusion. Lowering acceleration will result in real efficiency gains.

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Fri Nov 15, 2019 1:09 pm
by Birillo
jlv wrote:
Fri Nov 15, 2019 12:02 pm
Birillo wrote:
Fri Nov 15, 2019 11:35 am
Sounds like there is no real efficiency gain from lowering acceleration, although there are other advantages.
I'm not sure where you get that conclusion. Lowering acceleration will result in real efficiency gains.
Why is that?

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Fri Nov 15, 2019 3:08 pm
by dmacarthur
We put the studded tires on the Plus and made an essentially identical round trip of about 250 mile (with charging at the far end). Mileage result- loss of about another ten percent (3.3 vs. 3.7) of thruway m/KWH using about the same heat and headlights. This is pretty drastic, but it is the price we pay for living where studs are essential and having bought the Plus S without heat pump heater. It is amazing to see how fast the battery depletes compared to summertime daylight driving on smaller roads, where we average around 4.3-4. Heater, studded tires..... OTOH we get loads more power from the solar panels in the summer, when driving is essentially free, so winter usage is the cost of doing business.....

Re: 62kwh Leaf Plus Efficiency Posting

Posted: Fri Nov 15, 2019 6:18 pm
by DaveinOlyWA
jlv wrote:
Fri Nov 15, 2019 12:02 pm
Birillo wrote:
Fri Nov 15, 2019 11:35 am
Sounds like there is no real efficiency gain from lowering acceleration, although there are other advantages.
I'm not sure where you get that conclusion. Lowering acceleration will result in real efficiency gains.
+ 100!

Aggressive acceleration isn't the best thing for any battery and the higher the current, the higher the resistance so gentle acceleration will boost your efficiency dramatically. This is why I drive Eco all the time. In fact, its the ONLY mode that I use all the time. E Pedal I love but its not always engaged. D mode is used the least, B mode is at least 75% of the time, but Eco is always on simply because it smoothes the power demand spikes that may be fun to do but is wasteful and detrimental to range.

TBT; the newer LEAF's increased power means I rarely have to go as much as half throttle to do what I need to do.