tonymil
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Location: Latham, NY

Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Fri Sep 07, 2012 8:32 am

Personally I think the mpge figure has limited value. Basically the EPA set up the formula to compare BTU's. So the MiEV's 112 mpge means a lot less BTU's burned than a car that gets 30 mpg. But the selling point of an EV is reduced pollution and reduced fuel cost and the mpge figure by itself implies significantly reduced cost and reduced pollution which may not be the case depending on where you live. I think the EPA should come up with something like an Energy Star label for EV's.

Energy star labels on appliances give consumers an estimate of yearly energy consumption and yearly operating cost with the operating cost based on a national price average for electricity or natural gas. And the label shows how that appliance's operating cost compares to similar appliances. A similar label for EV's would be a bit more complex because it would have to compare EV's against gas vehicles, but it can be done. The consumer would then have to look at the average gas price and average electricity price used for the label and compare them to local gas and electricity prices.

Unfortunately this excludes pollution considerations. it would be even more difficult to come up with a simple chart that compares the pollution produced by an EV with the pollution produced by similar gas vehicles, especially because how much pollution an EV produces will depend on the type of power plant where you live. But I hate to see the selling point of EV's limited to a cost comparison.

JoeS
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Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Fri Sep 07, 2012 9:34 pm

Don wrote:...The only way to get a number than means ANYTHING is to get cost completely out of the equation...

Hi Don. Whereas we usually agree and complement (and compliment) each other, this topic is one we can roll up our sleeves on... ;)

First off, let's agree that we are only talking about energy ('fuel') and fuel consumption of electric and gasoline vehicles. All other elements, although important when talking about total operating costs, are off the table. Similarly, we're not talking about reduced pollution, health benefits, etc., that may have been significant reasons why we bought our iMiEV in the first place.

Since we're in the US and discussing the Monroney sticker, we'll stick with gallons and mpg and not litres or litres/100km. Happily, kilowatts and kWh are universal.

Next, I am well aware that the EPA took the energy equivalency approach, using 33.7kWh/gallon of gasoline. Within the Monroney sticker is their assumed cost basis for electricity (12 cents/kWh), with gasoline assumed cost being well-hidden but if you work it backwards from 22mpg and 15K miles/year and $12,600 over 5 years that gives us $3.697/gallon.

Allright, with that out of the way, what's the beef?

My contention is that COST is THE reason that "miles per gallon" is being discussed in the first place. The consumer doesn't give a darn about relative efficiencies - the consumer simply wants to know how much it will cost to drive the vehicle, with mpg and fuel cost in terms of cents/mile being reasonable and well-understood metrics.

The consumer looks at the iMiEV Monroney sticker 112mpge and thinks, wow, that's great! The examples alohart and you (Saudi Arabia) pointed out fully support my case. In terms of fuel cost per mile, in Hawaii alohart's efficient gasoline car costs less to drive (fuel cost) than our iMiEV. Thus, I contend, the Monroney sticker utilizing energy equivalence is misleading the consumer - in that locale, the iMiEV fuel cost/mile will be greater than that of an efficient gasoline car.

On the other hand, my table clearly shows the mpg equivalence for a given price of electricity and gasoline which the consumer can directly compare to any gas-guzzling chariot's mpg in the area they live in.

Don't worry, I don't expect to see my chart showing up anywhere soon ... it's primarily of academic interest, anyway, and I suspect most consumers don't know their electricity costs in terms of cents/kWhr.

Thus, Don, we agree to disagree: I believe COST and not energy efficiency is the underlying common denominator in mpg discussions.

BTW, tonymil, my take is that the Monroney sticker is indeed EPA's attempt at an EnergyStar label.

PS Don - I used nine cents/kWh (not six cents/kWh) for my own case - if I paid for my electricity. With my solar panels amortized elsewhere I get infinite mpg$ with my iMiEV. :roll:
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

Don
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Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Sat Sep 08, 2012 7:13 am

JoeS wrote:My contention is that COST is THE reason that "miles per gallon" is being discussed in the first place. The consumer doesn't give a darn about relative efficiencies - the consumer simply wants to know how much it will cost to drive the vehicle, with mpg and fuel cost in terms of cents/mile being reasonable and well-understood metrics

Don't worry, I don't expect to see my chart showing up anywhere soon ... it's primarily of academic interest, anyway, and I suspect most consumers don't know their electricity costs in terms of cents/kWhr.
I respectfully disagree - I think about all the average consumer really understands is the relative efficiencies

I don't think most consumers know what their actual operating costs are (or would be) anyway, Moroney sticker or not since the cost of gasoline varies so much week to week and state to state . . . . sometimes even hour to hour. About all they really understand is . . . . that it costs exactly half as much to drive a 40 mpg car as it does a 20 mpg car, so 40 is better than 20. President Clinton drove this point home Wednesday when he said that no matter what gasoline costs you, it's going to cost you half as much when you have one of the new 54.5 mpg cars in 2024

For most of us, that's all we understand

True, most don't know what they pay for a Kwh of electricity, but I'll bet most also don't have a clue what they paid for a gallon of gas averaged over the past year either. If you ask most any average driver what they paid in total for gasoline last year, I think you'll get lots of shrugged shoulders and very few could come up with a number within a couple hundred of the correct one. This is not something very many of us know. If my daughter had any clue, she'd make sure the kids were ready when the bus comes so she doesn't have to drive them to school

I truly believe that the mpg number alone means more to them than any other bit of information on the Moroney sticker . . . . and 112 mpg translates very well in the average brain which knows that 45 mpg is a really good number - Trying to get any more technical than that means that very few in your audience will get anything out of the discussion and trying to compare actual costs for them personally is a very complicated lost cause

When a stranger asks me about the car, invariably the first question is . . . . "What sort of mileage does it get?" - THAT'S how they compare one car with another. When I tell them it uses no gas and costs about 3 cents a mile to drive, I usually get blank stares . . . . I think because they have no idea how that compares to what they're driving. Before I bought this car, I had no idea how many cents per mile my ICE cost to drive - When the tank was empty, I filled it up, grateful that the tank was small and I could go 400 miles before I needed to do it again

It's almost impossible to talk dollars when you're discussing one car - Varied cost of gasoline, varied mileage depending how and where you drive, whether the car is well maintaned or not, summer or winter formula fuel, etc, etc. Now try to compare costs with a totally different kind of car which doesn't use gasoline at all and where the 'fuel' costs vary even more widely than the cost of gasoline does and all you're going to come up with is a million numbers which quickly beome meaningless for most of us

I understand that opinions will vary and I respect the fact that mine is no more valuable than anyone elses ;)

Don
2012 iMiEV SE Premium, White
2012 iMiEV SE, White
2017 Chevy Volt Premier
2014 Ford Transit Connect XLT SWB wagon, 14,000 miles
1979 Honda CBX six into six

iMiEVNZ7
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Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Sat Sep 08, 2012 3:27 pm

Here in New Zealand, Fuel is pretty expensive. Got invited to a party about 50 km away, as did my friend, we had to travel in seperate cars due to him being on call for his job, and I needed to be home earlier than him also.

He was discussing how expensive it was to travel there and back, particularly if he had to come back early to a call out and then back to the party to pick up his family.

I mentioned it would be only $ 3 NZ in the imiev, to which he said yes, but that would mean would not have enough power to go back to the party. I said he could swap to the petrol car if he had to go to work.

While at the party, even though I was there in the Hilux, I got talking to one of the guests about the imiev, and she was really impressed about the $ 3 refuel of the car, and the range for running the kids about to sports.

I may drop off a flyer to her about the car. While there, I spoke to a local councilor about power points for the local sports' grounds so people could refuel the imiev. He said he would put me in touch with the sports ground guy.

I have a client here in NZ on holiday from Aussie, and he can't get over how expensive it is to refuel the petrol Adventra here in NZ. He said it was about 80 $ Aus, compared to 140 $ NZ !.
To go the same distance in the imiev, it would be about 12 $ NZ.... :D :D :D

JoeS
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Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Wed Mar 26, 2014 10:38 am

Thought I'd revive this old thread - borrowing from the TOU thread -
Mart wrote:... please realize the MPGe is solely based on energy content, not price. It may be confusing to people to use it in a financial context, even though that's what most people are really wanting to know, "How much money do you save?". Unfortunately, people are used to MPG figures on the window, and by establishing MPGe the government has gotten itself into the same quagmire of measuring light bulbs and lamps in "incandescent watt equivalent" rather than using the more effective lumens and CRI. Edmunds argues for a move to Monthly Fuel Costs, but even this must be based on an "average" driver figure which varies as much as EPA MPG estimates. http://www.edmunds.com/car-news/fuel-mileage-equivalency.html

It's hard to come up with a money per mile estimate with fluctuating fuel prices, differing rates, and currency value fluctuations occurring daily or hourly. This editorial and the comments might be worth a read. http://insideevs.com/op-ed-time-new-metric/
Mart, thank you very much for this link. The comments section in that insideevs link I found very entertaining - it's been some time since I've seen so much lively banter about metrics - an interesting read if you're into that stuff.

The traditional metric for efficiency that the EV crowd used for many decades (a century?) was Wh/mile or Wh/km or kWh/100km (I won't get into a debate as to whether there should be a multiplication dot between the "W" and "h") - suffice it to say that distance is in the denominator and energy is in the numerator. Thus, the lower a vehicle's energy consumption/unit distance, the lower the number. When it comes to conventional ICE fuel consumption, the US is alone in using the back-asswards Miles Per Gallon (MPG) metric, whereas the rest of the world uses the far more logical litres/100km metric. Unfortunately, auto manufacturers have (and, I confess, so have I) been continuing this sin (?) and using the metric of miles/kWh; for example, the Leaf has this number displayed on their dash, although it further confuses the issue as it represents battery-to-wheels and not wall-to-wheels. Perhaps this distance/energy metric is in keeping with our national 'bigger is better' obsession?

Anyway, after all the give-and-take in the comments section of that article, there seemed to be no consensus on how to change EPA's current MPGe metric - even though that metric was vilified by most and the Joule over distance was felt to be the 'purest' metric.

In the end, it doesn't matter, as we all know that Your Mileage May Vary dramatically, depending on how you yourself drive your i-MiEV!
EVs: 2 Wht/Blu SE Prem., '13 Tesla MS85, 3 156v CorbinSparrows (2 Li-ion), 24v EcoScoot(LiFePO4)
EV Conv: 156v '86 Ram PU, 144v '65 Saab 96
Hybrids: 48v1kW bike
ICE: '88 Isuzu Trooper. Mothballed: '67 Saab (orig.owner), '76 MBZ L206D RHD RV

Mart
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Location: Midtown, Jackson, Mississippi

Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Wed Mar 26, 2014 7:06 pm

I think for the common man or woman on the street, the best you can tell them is the EPA estimate of 112 MPGe. After reminding them that it uses electricity instead of gasoline, they'll want to know the price of a "gallon" of electricity. :roll:

alohart
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Location: Honolulu, HI, and Uppsala, Sweden

Re: 288 MPG Best Case is More Than Twice the EPA Range and M

Wed Mar 26, 2014 8:02 pm

Mart wrote:I think for the common man or woman on the street, the best you can tell them is the EPA estimate of 112 MPGe. After reminding them that it uses electricity instead of gasoline, they'll want to know the price of a "gallon" of electricity. :roll:

The EPA considers 33.7 kWh equivalent to 1 gallon of gasoline, so 1 gallon of electricity would cost 33.7 divided by the cost of a kWh of electricity. In Honolulu, electricity costs ~30¢/kWh, so 1 gallon of electricity would cost ~$10 here.
Aloha,
Art
Honolulu: 2014 BMW i3 BEV (formerly 2012 i-MiEV SE)
Uppsala, Sweden: 2000 Honda Insight

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