How is MPG figured for 4xe

Skeethree

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Unfortunately that’s just more unquantifiable information. Who knows how many kilowatts went into all the recharges? I don’t always start recharging at 1%, might take 15kw, maybe only 6 depending on the miles I drive each day. The only viable, meaningful figures you can compare are:

1) electric only distance traveled from full charge to when the ICE first kicks on
2) mpg obtained once electric charge is gone, you have to reset one of the tripmeters to get this, and
3) total distance traveled with full tank and full electric charge until gas is refilled with no electric recharging

Of course it’s also fun to compare your total net out of pocket cost with the guy who bought the non-hybrid. My commute is 4 miles, I could drive 1000 miles on zero gallons of gas if I never took my Jeep anywhere else.
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SpaceCase

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Unfortunately that’s just more unquantifiable information. Who knows how many kilowatts went into all the recharges? I don’t always start recharging at 1%, might take 15kw, maybe only 6 depending on the miles I drive each day. The only viable, meaningful figures you can compare are:

1) electric only distance traveled from full charge to when the ICE first kicks on
2) mpg obtained once electric charge is gone, you have to reset one of the tripmeters to get this, and
3) total distance traveled with full tank and full electric charge until gas is refilled with no electric recharging

Of course it’s also fun to compare your total net out of pocket cost with the guy who bought the non-hybrid. My commute is 4 miles, I could drive 1000 miles on zero gallons of gas if I never took my Jeep anywhere else.
Here is my most recent test, this was using 11.3 gallons of gas. From these numbers, the MPG is being calculated as use of gas AND use of regenerated electricity. If it were calculated on gas only, my MPG should have read 16.52MPG, and if it was calculated on both electric and gas (including charges) it would read 33.45MPG.
20210529_112415.jpg


I plan on testing keeping track of "miles added" with recharges. It will obviously be a little off but will hopefully confirm my suspicions that the MPG displayed is for hybrid miles not including charges.
 
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Black96z

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Electric only miles are counted by trying to calculate "MPGe" and factor it into the MPG displayed. Its total BS to me. They should just have 2 meters, one for fuel used, one for kW/hr used.

If you reset your trip meter at a full charge and drive around, the active MPG screen will show 99 while moving in electric. If you look at your MPG average, it will represent the MPGe until the engine kicks on.
 

jdeolivares

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Electric only miles are counted by trying to calculate "MPGe" and factor it into the MPG displayed. Its total BS to me. They should just have 2 meters, one for fuel used, one for kW/hr used.

If you reset your trip meter at a full charge and drive around, the active MPG screen will show 99 while moving in electric. If you look at your MPG average, it will represent the MPGe until the engine kicks on.
Yes. I think you are right. It’s is calculating mpge when running full electric . The way you can tell is when you stop moving, there is still some electric energy being used and your mpg(e) starts to drop.
 

Skeethree

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Yes. I think you are right. It’s is calculating mpge when running full electric . The way you can tell is when you stop moving, there is still some electric energy being used and your mpg(e) starts to drop.
The problem is that automakers base MPGe on the equivalent electrical energy of a gallon of gasoline, which has no good correlation to what we pay for electricity. The easiest way to make a legitimate comparison is to figure out what electricity costs you (typically about 13-15 cents per kw/hr, or about 2 bucks to fully charge), then see how many miles you can drive for those two bucks, usually I see 24-28 miles. Since gasoline is about $3 per gallon here, I figure I get 36-42 miles on electricity for the cost of a gallon of gasoline. Even if you only get 20 miles with electricity, that’s still equal to 30 miles for the cost of a gallon of gasoline, but Jeep’s claim of 49 MPGe is really not a useful number.
 

SpaceCase

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If you reset your trip meter at a full charge and drive around, the active MPG screen will show 99 while moving in electric. If you look at your MPG average, it will represent the MPGe until the engine kicks on.
Tried this on my next recharge and the MPG read the same at 25.9MPG (never showed 99). It did change slightly while driving in all electric tho...
 
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