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Discussion Starter · #1 · (Edited)
The EPA "fuel economy rating" of the "Volt" is going to be very interesting.

Will the "Volt" be classified as 48 mpg hybrid ... OR ... something else?

My guess is that there will probably have to be a new classification that requires additional data to be included on the EPA label!

The one that GM won't like is probably some type of statistical data that answers the question "How FAR will the average Volt go on a FULL CHARGE before the IC engine cuts in when using an pre-aged (1, 3, 6, or 10 years?) battery pack?". That could require between 1,000 and 4,000 discharge/recharge cycles! This could easily take up to 3 years just to get the test data (depending on recharge/discharge cycle times) for the first year's product.

I think it is safe to say that WE consumers all know that aged/cycled rechargeable batteries can behave radically differently than new ones. So it is reasonable to believe the consumer (potential buyer) will want some type of comparative data ... OR ... an IRONCLAD "performance/durability" GUARANTEE.

It just occurred to me that this "New EPA Label" will require some type of data about the amount of electrical energy (recharging energy in kW hours) that is required to travel a given distance (under various conditions) when operating in full electrical mode! Maybe even requiring an "Energy Star" or some other electric energy rating from DOE? :D

It will be very interesting to see how these challenges are met and resolved. And, what data will ultimately be provided to the public by EPA (DOE?) ... and ... GM!
 

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The one that GM won't like is probably some type of statistical data that answers the question "How FAR will the average Volt go on a FULL CHARGE before the IC engine cuts in when using an pre-aged (1, 3, 6, or 10 years?) battery pack?". That could require between 1,000 and 4,000 discharge/recharge cycles! This could easily take up to 3 years just to get the test data (depending on recharge/discharge cycle times) for the first year's product.
I doubt the EPA would do require GM to do this. It would be like asking a manufacturer to list the mileage a car would get after it hit 100,000 miles.
 

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I think they should give an electric only range number. And then list the fuel economy of the IC engine when the battery hits the magic 35% charge limit and the IC engine is basically producing the electrical energy.

Basically two numbers.
Electric only range.
Fuel economy as if you forgot to plug it in last night.

None of this engine is required to maintain a 100% charge crap. Run the thing as it was designed to run.
 

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GM is guaranteeing 40 mile range on a 10 year battery. I don't see the point in this. GM is going to be the only one that will be able to offer this technology. The research they are doing now will ensure longevity.
 

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Discussion Starter · #5 ·
I think they should give an electric only range number. And then list the fuel economy of the IC engine when the battery hits the magic 35% charge limit and the IC engine is basically producing the electrical energy.

Basically two numbers.
Electric only range.
Fuel economy as if you forgot to plug it in last night.

None of this engine is required to maintain a 100% charge crap. Run the thing as it was designed to run.
Excellent suggestion!

Should there be a third number for "Electrical energy to run X miles in electric only mode"??

It seems that this would be absolutely necesssary to predict electrical energy consumption costs. Or don't they count?
 

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Excellent suggestion!

Should there be a third number for "Electrical energy to run X miles in electric only mode"??

It seems that this would be absolutely necesssary to predict electrical energy consumption costs. Or don't they count?
What would be the best would list the number as:

40m + 40mpg Highway
40m + 35mpg City

40 miles + average fuel economy so that we know that the first miles are ''free'' while after that the car does 40mpg on the highway and 35 in the city for exemple. This way you know exactly how much gas you burn and also the initial electric only range of the vehicle, because we will see a lot more volt-type vehicle in the future so each one will have his own initial electric only rating.
 

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Discussion Starter · #7 ·
What would be the best would list the number as:

40m + 40mpg Highway
40m + 35mpg City

40 miles + average fuel economy so that we know that the first miles are ''free'' while after that the car does 40mpg on the highway and 35 in the city for exemple. This way you know exactly how much gas you burn and also the initial electric only range of the vehicle, because we will see a lot more volt-type vehicle in the future so each one will have his own initial electric only rating.
So you propose a "guaranteed range" in city and highway plus a "traditional" city/highway rating ICE only.

I have a problem with 'we know that the first miles are ''free'''.

It seems that it would be absolutely necesssary to predict electrical energy consumption to allow estimation electrical costs. Or don't they count?
 

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So you propose a "guaranteed range" in city and highway plus a "traditional" city/highway rating ICE only.

I have a problem with 'we know that the first miles are ''free'''.

It seems that it would be absolutely necesssary to predict electrical energy consumption to allow estimation electrical costs. Or don't they count?

Yes no, who know's? If you arrive home with a 50% charge it will not cost the same to charge the battery then if you arrive home with a 80% and since you will probably not know what % is left in the battery then it will probably be hard to know how much it will cost to recharge.

But yes we could have a number in the like of: 5kwh per mile for 40m then 40mpg afterward, maybe something like:

40m (5kwh/m) + 40mpg

But then again the electricity is not paid directly so it would be kind of hard to relate just how much is used to charge your car and what is used for your normal other need's like lighting, heating, hot water, etc. I'm not sure it would be understood correctly by most people so probably should just be left out of the equation until people get used to how electric car's works.
 

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Discussion Starter · #10 · (Edited)
Yes no, who know's? If you arrive home with a 50% charge it will not cost the same to charge the battery then if you arrive home with a 80% and since you will probably not know what % is left in the battery then it will probably be hard to know how much it will cost to recharge.

But yes we could have a number in the like of: 5kwh per mile for 40m then 40mpg afterward, maybe something like:

40m (5kwh/m) + 40mpg

But then again the electricity is not paid directly so it would be kind of hard to relate just how much is used to charge your car and what is used for your normal other need's like lighting, heating, hot water, etc. I'm not sure it would be understood correctly by most people so probably should just be left out of the equation until people get used to how electric car's works.
I suggest that the vehicle "rate of electrical energy consumption" should be included in the "EPA Labeling" just as fuel consumption is now.

Your suggestion that because all electrical charges (heat, light, hot water, etc) would be bundled with the vehicle consumption is a weak justification for not having a number to predict vehicle operating costs when in "all electric mode". I agree that all credit card bills give a "total" but at least you can break out individual purchases and this is not true with electric billing.

So there IS an ABSOLUTE NEED to understand vehicle electrical consumption!

For instance, there is a big difference in cost between 0.5 kWh/mile and 5 kWh/mile (from your example above). Keep in mind that some utilities are charging OVER $0.10 per kWhr. If that were the case, electric mode could cost 500% more than gasoline operation if the rate was 5 kWh/mile at $0.10 per kWhr and gasoline at $4/gallon.

At least that is the way I see it ....
 

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What would be the best would list the number as:

40m + 40mpg Highway
40m + 35mpg City

40 miles + average fuel economy so that we know that the first miles are ''free'' while after that the car does 40mpg on the highway and 35 in the city for exemple. This way you know exactly how much gas you burn and also the initial electric only range of the vehicle, because we will see a lot more volt-type vehicle in the future so each one will have his own initial electric only rating.
The mpg for city and highway driving should be the same. You won't use more gas in city driving than you would in highway driving.
 

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The mpg for city and highway driving should be the same. You won't use more gas in city driving than you would in highway driving.
This is because the gasoline engine merely charges the battery pack, as opposed to driving the car, yes?
 

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Discussion Starter · #13 ·
I guess the other part of the challenge for GM's Volt is to keep the ICE combined average fuel economy above 50 mpg.

If the average ICE fuel economy drops below 46 mpg and the average electrical consumption rate is much above 1 kWh/mile, the Volt may not even be competitive with the 2008 Prius. And that is without considering purchase price.

I DO WISH THEM LUCK!!!
 

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Has GM given any information about the electrical usage per mile, per hour, or whatever? With that information, plus your utility's charge per kilowat hour, you could determine the approximate cost per mile and to re-charge overnight. There is a cost for the electricy to re-charge, so that should be an important part of the determination.
 

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I think they should give an electric only range number. And then list the fuel economy of the IC engine when the battery hits the magic 35% charge limit and the IC engine is basically producing the electrical energy.

Basically two numbers.
Electric only range.
Fuel economy as if you forgot to plug it in last night.

None of this engine is required to maintain a 100% charge crap. Run the thing as it was designed to run.
This seems reasonable - and workable. Perhaps the second (low) number should mandate a start charge of 35% and let it finish where it finishes - which should be noted as well.

It 'lines up' with how E85 capable vehicles are treated - although there is a useful third number there that isn't reported - the amount of gasoline used as opposed to fuel.

( We also need to get rid of the artificial misreporting on the diesel numbers ).

As others have noted, the big issue with the Volt is really more about how to count it in CAFE.

That is not an easy question to answer - all solutions have major limitations.

Maybe whats needed in order to develop a useful value is an onboard, tamper proof, accurate fuel count that can be downloaded and evaluated after a year or two of sales.
 

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I have a better idea - get rid of CAFE, so manufacturers can produce what they want.
Customers buy what they want, so why should the government tell the manufacturers what they have to produce, cars and trucks that the customer may not want?
The vehicles should be clean-running for the environment, but CAFE costs huge wastes in development costs, limits manufacturer options and profitability, and is a huge waste of time.
IF YOU BUILD IT (an outstanding vehicle) THEY WILL COME. A lot of the bad cars from 1973 onward were the result of government-required add-ons, and money . It looks like the government is doing it all over again with a 35 mpg requirement.
When do we stand up for our auto industry and say Enough? After it's gone? It's already on life supports.
 

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Discussion Starter · #17 ·
The mpg for city and highway driving should be the same. You won't use more gas in city driving than you would in highway driving.
Generally all vehicle seem to have differences in city and highway fuel economy.

Isn't the reason there is this different between city and highway for the ICE because of differences in load, acceleration, and energy recovery (for hybrids)?

Would this not also be also true for the Volt whether running with the ICE through the electric drive train or the battery?
 

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For an ice, stop and go driving produces its lowest rating, while running at full throttle produces single-digit numbers. Highway cruising produces the highest mileage, decreased by increasing wind resistance at higher highway speeds. If you have a car that displays instantaneous mpg, you'll see that's correct.
If you used roundabouts instead of traffic lights, your city mileage would improve.
If you set a 55 mph standard for the highway, highway mileage would improve. I don't advocate a 55 mph standard, but it would safe fuel. Big brother would send you your speeding tickets in the mail from all their speeding cameras.
 

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Discussion Starter · #19 ·
( We also need to get rid of the artificial misreporting on the diesel numbers ).
AMERICA 123, could you please clarify "artificial misreporting on the diesel numbers"?

Sorry about being off topic ... but you get to my curiosity.
 
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