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TonyWilliams
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Re: Power Consumption Table

Fri Sep 30, 2011 5:01 pm


rmerte
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Leaf Number: 7938

Re: Power Consumption Table

Thu Nov 24, 2011 9:12 am

One mistaken assumption I see: "and have a 10% remaining margin remaining to allow for possible diversions / traffic jams etc."

Note that traffic jams HELP your range when you're on the freeway. Remember that when you're not moving, you're not using any (relatively) electricity, compared to running a gasoline engine. :)

Based on this profile you should be fine. I drive minimum 56 miles RT every day, with plenty of hills.

DaveinOlyWA
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Re: Power Consumption Table

Thu Nov 24, 2011 10:49 am

i have to question your trips having "marginal" results. i have to say that the trips even in very bad weather conditions should use no more than 75-80% of your capacity one way and 5 hours is more than enough time to recharge

what i think you need to do is at the end of a marginal trip. continue on a controlled route (circling if you must) to see exactly what is left in the pack. i think you are more a victim of the GOM than any range restriction
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 deceased. 29,413 miles. 2018 S40; 15,000 miles, 478 GIDs, 37.0 kwh 109.81 Ahr , SOH 94.61, Hx 120.15
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TomT
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Location: California, now Georgia
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Re: Power Consumption Table

Thu Nov 24, 2011 10:54 am

Not always, actually. If you can move at a fairly constant low speed, yes, but if you are in stop and go driving, it can actually eat in to your range more than a constant slow speed. My M/Kwh is almost always lower when I am in stop and go, 5 or 10 mph traffic than when I can cruise at a constant, reasonable, slower speed... The need to accelerate and then decelerate, stopping, and parasitic loses add up in such a condition.


rmerte wrote:One mistaken assumption I see: "and have a 10% remaining margin remaining to allow for possible diversions / traffic jams etc."
Note that traffic jams HELP your range when you're on the freeway. Remember that when you're not moving, you're not using any (relatively) electricity, compared to running a gasoline engine.
Leaf SL 2011 to 2016, Volt Premier 2016 to 2019, and now:
2019 Model 3; LR, RWD, FSD, 19" Sport Wheels, silver/black; built 3/17/19, delivered 3/29/19.

DaveinOlyWA
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Joined: Sat Apr 24, 2010 7:43 pm
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Location: Olympia, WA
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Re: Power Consumption Table

Thu Nov 24, 2011 10:59 am

TomT wrote:Not always, actually. If you can move at a fairly constant low speed, yes, but if you are in stop and go driving, it can actually eat in to your range more than a constant slow speed. My M/Kwh is almost always lower when I am in stop and go, 5 or 10 mph traffic than when I can cruise at a constant, reasonable, slower speed... The need to accelerate and then decelerate, stopping, and parasitic loses add up in such a condition.


rmerte wrote:One mistaken assumption I see: "and have a 10% remaining margin remaining to allow for possible diversions / traffic jams etc."
Note that traffic jams HELP your range when you're on the freeway. Remember that when you're not moving, you're not using any (relatively) electricity, compared to running a gasoline engine.


stop and go is NEVER going to be more efficient that constant velocity unless talking about very high speeds. also keep in mind; in any time scenario, several things have fixed usage so the longer on the road, the lower the efficiency. now in most cases, time is insignificant. but if spending an hour in stop and go running a heater using 2 Kw /hour that is 6-9 miles of range gone
2011 SL; 44,598 miles. 2013 S; 44,840 miles.2016 S30 deceased. 29,413 miles. 2018 S40; 15,000 miles, 478 GIDs, 37.0 kwh 109.81 Ahr , SOH 94.61, Hx 120.15
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tbleakne
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Leaf Number: 2400
Location: Claremont, CA

Re: Power Consumption Table

Thu Nov 24, 2011 11:41 am

TomT wrote:Not always, actually. If you can move at a fairly constant low speed, yes, but if you are in stop and go driving, it can actually eat in to your range more than a constant slow speed. My M/Kwh is almost always lower when I am in stop and go, 5 or 10 mph traffic than when I can cruise at a constant, reasonable, slower speed... The need to accelerate and then decelerate, stopping, and parasitic loses add up in such a condition.


rmerte wrote:One mistaken assumption I see: "and have a 10% remaining margin remaining to allow for possible diversions / traffic jams etc."
Note that traffic jams HELP your range when you're on the freeway. Remember that when you're not moving, you're not using any (relatively) electricity, compared to running a gasoline engine.

TomT +1. On freeways with only gentle up and down grades, destination near same altitude as start, at steady speeds, no climate control, I can achieve 5.1 to 5.2 mi/kwh. Stop and go (0-30 mph) can cut this almost in half, no matter how careful I am to watch traffic several cars ahead of me to smooth-out my speed. In normal traffic I let the speed creep up above 60 mph on short gentle downgrades to avoid the inefficiencies of regen.

Your elevation profile shows some grades that might not be "gentle." On steeper upgrades I would suggest you drop your speed as low as is safe for the surrounding traffic, 50 mph or even lower, to avoid motor draws exceeding 25 kWs. On steeper downgrades you may have to use some regen to keep speed down, otherwise you will have higher aerodynamic losses.

You might consider building the SOC meter (see CanBus sub-forum) to more accurately track you battery State-of-Charge. I find it very helpful for estimating exactly how far I can go and how much reserve I have left.
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LEAFfan
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Leaf Number: 1855
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Re: Power Consumption Table

Thu Nov 24, 2011 12:54 pm

tbleakne wrote:On freeways with only gentle up and down grades, destination near same altitude as start, at steady speeds, no climate control, I can achieve 5.1 to 5.2 mi/kwh.


At what speed do you travel on the freeways to get 5.1-5.2? According to the chart, that would be around 45mph. Did you reset your m/kW h meter when you reached your set speed? I've hit 5.0 @60mph (CC) twice so far on a 20mi., all freeway RT, relatively flat, same starting altitude, temp low 70s, no HVAC. I can tell you that there is a huge difference when the ambient temps are below 70 on the freeway AND in city street driving.
2013 LEAF SV Del. 2/28/13
2013 LEAF World Record for Most Miles Driven On One Charge-188 miles/8.8 m/kW h
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