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I always wondered why my lifetime efficiency would go down when my trip meter is clearly displaying that my efficiency is going up. I think i figured it out today. While at a Fast charger my Lifetime as displayed in the My Chevrolet app was at 3.7 Miles per kilowatt. After charging for an hour the app registered 3.6 K/M lifetime. The app is apparently calculating with Kilowatts added to the battery, rather than kilowatts used by the Bolt. I will further watch to see if lifetime goes up as I drive, but don't charge. My car is relatively new, so this result should smooth out over the years.
 

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I always wondered why my lifetime efficiency would go down when my trip meter is clearly displaying that my efficiency is going up. I think i figured it out today. While at a Fast charger my Lifetime as displayed in the My Chevrolet app was at 3.7 Miles per kilowatt. After charging for an hour the app registered 3.6 K/M lifetime. The app is apparently calculating with Kilowatts added to the battery, rather than kilowatts used by the Bolt. I will further watch to see if lifetime goes up as I drive, but don't charge. My car is relatively new, so this result should smooth out over the years.
I am SOOOOO glad you posted this.

I was wondering what the whole deal was on the lifetime efficiency and found your post in my effort to find a way to reset it.

I too will watch mine and post what happens (I'm only a couple of weeks into ownership) and would love to see you post some additional information about what you see over time.
 

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My lifetime started out at 1.2 when I got the car (with all of 10 miles on it, 3 of which was the test drive). It's been steadily climbing. It's now at 2.7 (with 1627 miles on it).
 

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The situation by devbolt is definitely what I am seeing. It was very low but is climbing.

The irony is that the efficiency as reported on the car dashboard is at 4.1 (this again is lifetime efficiency), however on the mychevy app it only shows 2.3. My car is currently only has a little above 300 miles on it.

Odd.
 

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The situation by devbolt is definitely what I am seeing. It was very low but is climbing.

The irony is that the efficiency as reported on the car dashboard is at 4.1 (this again is lifetime efficiency), however on the mychevy app it only shows 2.3. My car is currently only has a little above 300 miles on it.

Odd.
More than likely the dealer reset the trip-meter prior to giving it to you. How many miles does the trip meter show with the 4.1 miles per kWh? I'm guessing it's less than the actual number of miles on the car...
 

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More than likely the dealer reset the trip-meter prior to giving it to you. How many miles does the trip meter show with the 4.1 miles per kWh? I'm guessing it's less than the actual number of miles on the car...
I should have mentioned that because at first I was thinking the same. But no, the trip meter is showing the exact same (now 343) miles on the car as the odometer. The Vehicle Status section of the mychevy app is also showing 343 but of course it only displays odometer data (for total miles that is).

Wow, don't know if I made that more confusing while I was trying to be more clear.

;)
 

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I should have mentioned that because at first I was thinking the same. But no, the trip meter is showing the exact same (now 343) miles on the car as the odometer. The Vehicle Status section of the mychevy app is also showing 343 but of course it only displays odometer data (for total miles that is).

Wow, don't know if I made that more confusing while I was trying to be more clear.

;)
My point is that there's no lifetime effeciency screen in either the DIC (where the speedometer is), or the Infotainment screen. If you are seeing a miles/kWh figure, it's from the trip meter in the DIC. The myChevrolet app or the my.chevrolet.com website are the only two places to get what the car thinks is the lifetime effeciency. Also, the myChevrolet app/website shows effeciency since the last full charge (either to the Hilltop Reserve level or an actual full charge), and not since the last time the trip meter was reset.

The app seems to have more accurate information than the website. Or at least it's presented better
 

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The situation by devbolt is definitely what I am seeing. It was very low but is climbing.

The irony is that the efficiency as reported on the car dashboard is at 4.1 (this again is lifetime efficiency), however on the mychevy app it only shows 2.3. My car is currently only has a little above 300 miles on it.

Odd.
So I think Jchag totally nailed this. And your data just proved his/her theory.

Your true efficiency is 4.1 mile/kWh at 300 miles, which means you used 300/4.1 = 73.17 kWh to get to 300 miles.
But the efficiency shown in the app is based on how much energy is charged into battery instead of how much energy is used.
So if you have 100% (60kWh) in the battery, the efficiency shown by the app is
300 miles / (73.17 kWh used energy + 60 kWh energy left in battery) = 2.25 miles/kWh.
That explains the 2.3 you see in mychevy.
 

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I've been trying to figure out the wonky numbers in MyChevrolet, by recording the numbers I see (on the website) into a spreadsheet. I have some observations:

- The "Electric Economy" is definitely charge added to the battery, not the charge expended. (I wish I saw this original post earlier!) I still have low enough total miles (1200) that driving the battery down moves this number. It makes sense then this number will become more reliable as you rack up more miles and more recharges, as weight of the next recharge is averaged out.

- There are two Range figures reported in the "Charging Status" part of the display, "Estimated Electric Range" and "Estimated Total Range". The "Total" figure will jump around when you refresh the charging status. I realized that "Total" randomly reports the estimated range value, or the estimated max, or the estimated min, which you'd see on the DIC.

- The "Electricity Used" value under the Mileage & Efficiency section (reported as "Kwh") is always the same value as the "Estimated Total Range" (which was the estimated min or max or likely range). This seems utterly useless then.

- Miles, Est Fuel Saved, Est CO2 Avoided seem to be reliable (they are all consistent with each other and don't randomly jump around on refresh).

My "Electric Economy" value (mine is currently around 30 kWh/100mi) looks high to me, considering I've been averaging over 4 mi/kWh. I'm thinking the difference is all charge on that Bolt prior to our taking delivery is probably included. If so, that would hopefully also become relatively insignificant once we rack up enough miles.
 

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No “Lifetime” efficiency rating in car

I have 3200 miles on my Bolt. I never reset my trip meter, because it’s the only place to accurately get my efficiency numbers. Mine is at 4.2miles/kWh. There is a huge discrepancy though when I go to Chevy App. It lists it at a seemingly low 3.2miles/kWh ! I’ve been watching the “averages bar graph” in the energy info, and 4.2 seems like a much more accurate number. What gives Chevy?!
 

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I have 3200 miles on my Bolt. I never reset my trip meter, because it’s the only place to accurately get my efficiency numbers. Mine is at 4.2miles/kWh. There is a huge discrepancy though when I go to Chevy App. It lists it at a seemingly low 3.2miles/kWh ! I’ve been watching the “averages bar graph” in the energy info, and 4.2 seems like a much more accurate number. What gives Chevy?!
Go back and read earlier posts in this thread, people figured it out. The figure is based on energy put into the car, not energy used. Thus all the charge currently in your battery is currently counting against you.

Yes, this is stupid.
 

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If the focus is narrowly on operating cost that sorta makes sense:

You incur the cost the moment you obtain the electricity. No miles yet? Then show high Kw/mile!

Yes that is a stupid way to present the information.
 

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New owner here. So...what is the best way to keep track of lifetime? Spreadsheet using the Energy Detail data or Spreadsheet using trip meter data?
If by Energy Detail you mean the screen with the pie chart/ring that divides up your energy usage between driving, heating, and battery conditioning, and by "trip meter data" you mean the number below the speedometer that shows miles traveled on current trip along with mi/kWh efficiency, I'd say why not both? They both derive from the same numbers.

If you're just interested in mi/kWh efficiency, the trip meter data should be fine. I forget the type of average this would be since it groups the miles into "trips" and if that will be different than dividing the odometer miles by the lifetime kWh used when you took the odometer reading. Off-the-cuff I'd say the trip meter data can be thought of as a moving average. I don't know if you can add up moving averages than average them again to get the same average as odometer/kWh.
 

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I'm with TJam: use the trip meter, don't reset it. Mine shows 3.5 miles per kWh over 2286 miles. I drive about one third freeway (around 70 mph), one third expressway (around 50 mph) and one third local streets (25 to 35 mph). I'm fond of hard acceleration, as the tractor beam on the Bolt gives me a thrill.
 
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