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I recently took a 100-mile trip in my gen 2 Volt. I wanted to compare the mileage with making the same trip on my old gen 1. I was disappointed that the mileage appeared to be 54 MPGe, which is less mileage. So I did some figuring and the mileage was around 74, which is considerably better. To me, the mileage is the distance I drive divided by the amount of gas I had to buy to do it. To me MPGe is irrelevant and essentially meaningless.
 

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Just go by kWh/mi. The MPGe is just a reminder that there is 33 kWh of energy in one gallon of gasoline (that internal combustion engines squander most of it as waste heat). If you push the little box on the center display that shows MPGe, it will toggle to total trip MPG as you described as a comparison.
 

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I recently took a 100-mile trip in my gen 2 Volt. I wanted to compare the mileage with making the same trip on my old gen 1. I was disappointed that the mileage appeared to be 54 MPGe, which is less mileage. So I did some figuring and the mileage was around 74, which is considerably better. To me, the mileage is the distance I drive divided by the amount of gas I had to buy to do it. To me MPGe is irrelevant and essentially meaningless.
So feel free to ignore it :)
 

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It's a useless number and it has no business being on the display especially since they don't display MPKWh which is the number that you really want to see. Energy is purchased as gallons of gas and KWh of electricity, the price of each is mostly unrelated to the other. The car does display MPG but to get MPKWh you have to pull out a calculator which is silly.
 

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I never look at MPGe. However, having said that, I don't understand why or how the MPGe for 2.0 would be lower than then MPGe for 1.0. That's something of a mystery. Are you comparing MPGe with MPG? Obviously with an EREV the MPGe will be lower since MPG doesn't account for the use of the electricity.
 

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MPGe is the more meaningful number as it is total energy used, including charging losses. The old MPG number on the Volt 1 was misleading. It is a figure for avoided gallons of gasoline, not actual efficiency. I could say I am very efficient walker, it only takes me 10 steps to go the 5 miles to work. In reality it takes me 10 steps plus 1.5 kwh of electricity.
 

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I ... To me, the mileage is the distance I drive divided by the amount of gas I had to buy to do it. To me MPGe is irrelevant and essentially meaningless.
this is almost funny to see. there are hundreds of threads from the 2008-2012 time frame where forum members railed about how meaningless MPG was and argued about how to best measure and communicate total efficiency and whether that total efficiency had to include power plant and distribution and recharging and refinery and transport efficiencies or not. the most vocal (prolific?) writers argued for the importance of an MPGe number, which you and I think is just not important to us...
enjoy your volt
 

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I always thought the standard MPG display on the energy screen of the gen 1 was just miles traveled divided by gas used, up to 250. Maybe I was wrong all this time. One thing about MPGe, you don't have to worry about infinite mileage.
 

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I'd like to see a display for MPG that is just for miles traveled on gas. Also a mpkWh display for just miles traveled on electricity. Along with knowing AER, I think those numbers tell the whole story about the car's efficiency, and are also easy for anyone to understand.
 

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If it is irrelevant to you, just ignore it. MPGe was proposed by EPA to measure efficiency of electric vehicles that make sense in a predominantly gasoline world.
And marketers love it. It's easy to mislead unsuspecting consumers when you say a minivan gets 80 MPGe (ignore the small, insignificant 'e' there!).

If one gallon of gasoline as approximately the same energy content as 33 kWh of electricity, it can help to compare apples to oranges, like if you are comparing the caloric content of each of those.

My volt can go 70 miles on 14.7 kWh, sooo that equates to about 0.45 gallons of gas, which is like a gas car that can get 155 miles-per-gallon of gasoline. (I think I did that right....). However, that still does not factor in the price of said fuel, so the comparison isn't really done. This is a drawback of MPGe.

In my case, gas is $2.15/gal (at the moment) and electricity is $0.12/kWh, so that 70 miles costs me $1.78 in electricity. Now the money question: what MPG would a gasser need to get to match that? Answer: 84.5 MPG.

Since gas costs vary greatly nation-wide, it falls back to just MPGe for the comparison by the average consumer.
 

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MPGe is useful (sort of) to a car shopper comparing different cars, but once one buys a particular car, that number is no longer of any use. My Honda motorcycle displays instant and average mpg. I would like to see the same in the Volt for gas operation, along with a m/kWh since last full charge. The readouts should be selectable on the DIC display, as this info would probably confuse some people.
 

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I'd like to see a display for MPG that is just for miles traveled on gas.
It is right there on the first page of the energy screen-push the square that shows MPGe. See the two dots under the square?...that's the page1/page 2 toggle. Unfortunately you lose some other info when you go away from the MPGe display.
 

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And marketers love it. It's easy to mislead unsuspecting consumers ...My volt can go 70 miles on 14.7 kWh, ..

In my case, gas is $2.15/gal (at the moment) and electricity is $0.12/kWh, so that 70 miles costs me $1.78 in electricity. Now the money question: what MPG would a gasser need to get to match that? Answer: 84.5 MPG.
...
your are ignoring charging overhead, which is approximately 30% on the Volt. the amount of power going through your meter at home is approximately 30% higher than the electric power used as reported by the volt. if your car tell you that a drive used 10.0 KWh, then you will consume and be billed for 13 KWh to refill the battery.
 

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It is right there on the first page of the energy screen-push the square that shows MPGe. See the two dots under the square?...that's the page1/page 2 toggle. Unfortunately you lose some other info when you go away from the MPGe display.
^^^^ like he said -- the part in the red border below.

 

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Here last i went higher MPGe and MPG. Here picture. i work for Amazon and lot of hills.




Sent from my Nexus 5X using Tapatalk
 

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I am in the process of studying and researching all about the Volt before purchasing my first and now I am so confused. That screen is very confusing to me. Two MPGe readings? Maybe I should rethink this whole thing.
 

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your are ignoring charging overhead, which is approximately 30% on the Volt. the amount of power going through your meter at home is approximately 30% higher than the electric power used as reported by the volt. if your car tell you that a drive used 10.0 KWh, then you will consume and be billed for 13 KWh to refill the battery.
30% loss in charging? I find that difficult to believe. Certainly wasn't that big a gap between what my car displayed as used for a recent drive to Disneyland versus what the ChargePoint charger billed me for. More like <20% as I recall. Still the loss was much higher than I recall my CMAX experiencing.

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your are ignoring charging overhead, which is approximately 30% on the Volt. the amount of power going through your meter at home is approximately 30% higher than the electric power used as reported by the volt. if your car tell you that a drive used 10.0 KWh, then you will consume and be billed for 13 KWh to refill the battery.
Source?

The voltage and temperature effect charging losses, I charge on 240V so my losses are less than someone charging on 120V. Some good information and numbers here: http://gm-volt.com/forum/archive/index.php/t-100681.html

I Only lose around 14% efficiency with my charge setup. Simply put, 30% is *not* a universal number. And from what I'm seeing, the absolute worst case scenario for charging your car on a slow 120V 8A line.
 
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