PhilPen
Posts: 72
Joined: Mon Oct 31, 2016 9:54 am
Location: Hamden, CT

Re: List your miles and MPGe

Thu Apr 20, 2017 5:19 am

If your primary concern is environmentalist you will want to compare your EV to gasoline in terms of relative CO2 production.
When you burn one gallon of pure gasoline you get 19.64 pounds of carbon dioxide (CO2) (from E10, gas containing 10% ethanol, you get 18.95 pounds of CO2).
If you go to https://oaspub.epa.gov/powpro/ept_pack.charts you can get a figure for how clean or otherwise your electricity generation is by entering your zip code and electricity supplier.
In my area of CT using UI for electricity the CO2 emission rate is given as 571 pounds of CO2 per MWh or 0.571 lbs/Kwh (a relatively clean state). Thus for the equivalent CO2 as produced by burning one gallon of pure gasoline I'll get 19.64/0.571 = 34.4 KWh (for E10 its 33.2 KWh).
Multiplying this value by my charger efficiency, I’ll use 87.8 % as my L2 charger efficiency ( https://www.veic.org/docs/Transportatio ... Report.pdf ). Thus for the same quantity of CO2 released by burning one gallon of gas I’ll get 30.2 KWh in my battery. Since my current average is 4.1miles/KWh (it’s started going up with the warmer weather) I get a pollution mpge of 124.

Efficiency losses during electricity distribution via the grid would already have been taken into account if the government published figure for CO2 lbs/Kwh is based upon what the customer receives, which seems logical. However, there are additional losses incurred with gasoline that I have ignored, so gasoline is in actuality dirtier than the 19-20 lbs of CO2 you get per gallon by simply burning it, because it takes significant energy to refine and distribute the gasoline… and I’ve ignored this. My ultimate aim would be to use home solar power for my electricity source then I’d generate no net CO2 from driving. Unfortunately I live in a very shady area so I’m not the best candidate for this (I don’t want to cut down multiple large trees to go solar).
2015 Spark EV 2LT electric blue with DCFC
2016 Spark EV 2LT salsa red with DCFC

NORTON
Posts: 1223
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: List your miles and MPGe

Thu Apr 20, 2017 9:55 am

PhilPen wrote:If your primary concern is environmentalist you will want to compare your EV to gasoline .....
My ultimate aim would be to use home solar power for my electricity source then I’d generate no net CO2 from driving. ...
Right, it should be compared as 'Well to Wheel' for gassers and 'Mine to Wheel' (for the coal/nuclear portion of the grid) for EV's.

It's a really complicated subject.

Then talk about where the 'Wells and Mines' are located. But then that starts a political talk, never mind....
At least the electricity is locally produced, theoretically.
And home solar system gives you 'HOMEMADE' power !
Used '14 2LT w/ DCFC. +69 K miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 2nd guess not covered by warranty and cost $800. 3rd guess fixed the problem.

SparkSS
Posts: 15
Joined: Fri Mar 31, 2017 2:51 pm

Re: List your miles and MPGe

Thu Apr 20, 2017 11:04 am

NORTON wrote:
PhilPen wrote:If your primary concern is environmentalist you will want to compare your EV to gasoline .....
My ultimate aim would be to use home solar power for my electricity source then I’d generate no net CO2 from driving. ...
Right, it should be compared as 'Well to Wheel' for gassers and 'Mine to Wheel' (for the coal/nuclear portion of the grid) for EV's.

It's a really complicated subject.

Then talk about where the 'Wells and Mines' are located. But then that starts a political talk, never mind....
At least the electricity is locally produced, theoretically.
And home solar system gives you 'HOMEMADE' power !
"It's a really complicated subject."

That is both absolutely correct and very understated.

Not even addressed were the issues of mining the raw materials to produce the vehicles, especially the impacts of mining the materials for the battery packs. Or the environmental impact of sliced, diced, and roasted birds from wind and solar power generation. Or the human costs of people dying because they cannot afford transportation or the power generation needed to maintain hospitals, infrastructure, and sanitation.

Yeah, it's a really complicated subject. Lots of unintended consequences, and even questionable intended consequences.

fr100
Posts: 27
Joined: Sun Dec 13, 2015 4:11 am

Re: List your miles and MPGe

Sun Jun 25, 2017 11:30 pm

My lifetime MPGe always shows 132 even though my drives are way more efficient than that. I don't know why.

http://imgur.com/a/gkO60

scrambler
Posts: 135
Joined: Sat Jan 14, 2017 4:11 pm

Re: List your miles and MPGe

Mon Jun 26, 2017 9:57 am

fr100 wrote:My lifetime MPGe always shows 132 even though my drives are way more efficient than that. I don't know why.

http://imgur.com/a/gkO60
Things to consider:
Have you had the car from the start, or did it have a previous owner? They could have had a different driving style.
Do you live in a place where you have to use the heater and or the AC a lot during some month?
If so that would also mean, the battery conditioning could be used a lot during these periods too. Both of these will decrease your overall efficiency even if your driving style is very efficient.

NORTON
Posts: 1223
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: List your miles and MPGe

Mon Jun 26, 2017 10:38 am

fr100 wrote:My lifetime MPGe always shows 132 even though my drives are way more efficient than that. I don't know why.
I was seeing the same dang thing. That number would never move up even though I'd have most of my drives reporting much better numbers.

Now I don't have the fancy parts of that app, so frankly my dear,,,

I now know when it's done charging or if some AH unplugged it. That's the important parts.
Used '14 2LT w/ DCFC. +69 K miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 2nd guess not covered by warranty and cost $800. 3rd guess fixed the problem.

ncerna
Posts: 76
Joined: Sat Jun 17, 2017 4:25 pm

Re: List your miles and MPGe

Mon Jun 26, 2017 1:54 pm

How do you figure out the MPGe? When I charge my car completely, I think it shows that I have like 85 miles available.

TheLondonBroiler
Posts: 179
Joined: Tue Oct 31, 2017 6:25 am

Re: List your miles and MPGe

Thu Mar 22, 2018 2:33 pm

2015 2LT 20,553 miles Displays 5.1mi/kw average since new (previous owner never reset tripometer).

I've put right at four thousand miles in two months of ownership. Car was a southern California lease before it moved to South Carolina.

When people ask me about efficiency, I give them the EPA formula plus charging loss((5.1x33.7)/x0.8(L2 charging loss)) 137mpge and tell them it costs me about 4¢/mile and that my Toyota Corolla had cost me ~8¢/mile in fuel lifetime ownership.

I use a Juice Box Pro 40 Lite charger and have observed charging efficiency between .79-.85, using the Juice Box App and vehicle information.
Last edited by TheLondonBroiler on Fri Mar 23, 2018 8:11 am, edited 1 time in total.
2015 Spark EV w/ DCFC 46,XXX miles
Purchased 1/20/18 w/ 16,5XX miles
2019 Bolt EV w/ DCFC 6,XXX miles
Purchased 3/16/19 w/ 87 miles

Chris101
Posts: 98
Joined: Thu Jan 18, 2018 11:37 am

Re: List your miles and MPGe

Fri Mar 23, 2018 2:32 am

How are you guys seeing the MPGe anyway? Is this ONLY via an App and having ONStar because I don't see an option for this in the car itself.

This entire winter has shown us 3.7kwh per mile and it never seems to waver :(

Yesterday I drove very conservative in L, DRL off never going above 56mph on the highway with cruise set ON and STILL only 3.7kwh per mile efficiency displayed after a 60+ mile jaunt. (It was 42 degrees at the time)

NORTON
Posts: 1223
Joined: Fri May 01, 2015 5:52 am
Location: KC,MO

Re: List your miles and MPGe

Fri Mar 23, 2018 5:04 am

Chris101 wrote:How are you guys seeing the MPGe anyway? ...

This entire winter has shown us 3.7kwh per mile and it never seems to waver :(

... 56mph on the highway with cruise set ON and STILL only 3.7kwh per mile efficiency displayed after a 60+ mile jaunt. (It was 42 degrees at the time)
I can't answer the MPGe question, but 3.7 miles / kWh is,, maybe normal in the winter (?), but your example should have been better, I would think.

Keep in mind there are 2 displays for energy usage.
>There is the resettable page, where a trip mileage and mi/kWh keeps an ongoing record.
>Then there is the brief trip display at shutdown that only shows your last trip data.

Hang in there...
Have you heard it's SPRING!!! :mrgreen:
Used '14 2LT w/ DCFC. +69 K miles.
Mostly free charging! Only one LONG visit to the shop....
GM needs Modern Troubleshooting tools for Modern EV's.
3 step Trouble Tree, 2nd guess not covered by warranty and cost $800. 3rd guess fixed the problem.

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