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Discussion Starter #1
Yesterday I drove 105.2 km using 13.7KW on a single charge before switching to ice. In this past winter I've noticed that the car would 14.2-14.3KW on my daily drive. Why such a difference in KW usage from cold to hot weather??
 

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Less regen maybe? It's more about what's left on the battery than what's been used, so if you're not braking as much that's one possibility.

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Less regen maybe? It's more about what's left on the battery than what's been used, so if you're not braking as much that's one possibility.

Sent from my Nexus 6P using Tapatalk
The "kWh Used" number is an estimate, not a meter reading, because it’s actually a net calculation = grid power consumed less regen put back in. The system accounts for variation in the amount of regen during a trip by subtracting it from the kWh Used number on the display (you can sometimes see the number get smaller because of regen as you drive down a long hill), so you, in effect, get to use it again. Since the amount of grid power is consistent from full charge to full charge, the more hills you drove down and the more braking you did, the higher the total power consumed would be if the "kWh used" number was the sum of the grid power used and the regen you got during the trip instead of the difference. By eliminating regen count from the total trip kWh Used, you get a fairly consistent kWh Used number for every fully depleted battery use.

Of course, driving down the road uses the battery and lowers the state of charge, and getting regen by driving down a hill then raises it again. Once the Battery State Estimate algorithm has determined the SOC has dropped to the minimum allowable point, the car switches to ICE and the battery is considered "fully depleted." Why the computer determines it’s time to switch on the ICE one day when you’ve used 14 kWh of your Gen 2's power, and another day when you’ve only used 13.7, is for others to explain...
 

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Regen shouldn't impact the kWh used number unless you net a large elevation change since it subtracts off regen, the number is an indirect measurement of how much power has entered/exited the battery (I would consider it a software meter). My guess is state of charge might have been slightly different at start, or you stopped for a longer period of time and maybe it reestimated state of charge. Maybe you were driving differently? If your net elevation change is zero (charge at the same place and don't use gas on a run) though it should be consistent. Once the engine turns on, ignore that reading.

Actually, did your engine run due to temp in the winter? That could mess with it too depending on how it accounts for that power. My reading gets all messed up with ERDTT.
 

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Discussion Starter #5
On the days that were warmer than -10C but below 0C the car would consistanly use 14.2-14.3KW before turning ICE on. I'll keep an eye on it this week and report back.
 
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