A News Article (Kinda!) Supports GM's 2-Mode Strategy

[uvaeeman]

The article says that big savings for a consumer can come from small improvements to inefficient vehicles. Of course if you don't need an inefficient vehicle then the smartest thing is to get something else. But assuming that you have a big family or haul things or whatever, this basically lines up with GM's two-mode hybrid strategy - Nail the least fuel-efficient vehicles first. Who'da thunk?

http://www.cnn.com/2008/TECH/06/20/f....ap/index.html

With the price topping $4-a-gallon everybody wants to save gas, but depending on those miles-per-gallon ratings may be misleading.
Improving fuel efficiency by just 1 mpg can save hundreds of dollars a year, a new report says.

Strange as it may sound, rating cars at gallons-per-mile may be more useful, say a pair of university researchers.
....
"There are significant savings to be had by improving efficiency by even two or three miles per gallon on inefficient cars, but because we communicate in miles per gallon, that savings is not immediately evident to consumers," said Soll.
....
Gillis calculated that at $4 a gallon, over 10,000 miles, an improvement from 12 mpg to 13 mpg would save $256. For the owner of a 33 mpg car to save that much, mileage would have to go up to 40 mpg, he said.

In other words, if you need to replace a car and plan to buy a similar one, a small MPG improvement saves more dollars than the same MPG improvement in an econo-car.

[mgescuro]

It is smart.
I wonder how many people who bought SUV's actually need them for something reasonable like hauling a large family?

The 2-Mode system won't save the SUV.... but it will continue to make it a viable option for more fuel conscious families that actually need an SUV.

[zete]

Originally Posted by mgescuro

It is smart.
I wonder how many people who bought SUV's actually need them for something reasonable like hauling a large family?

The 2-Mode system won't save the SUV.... but it will continue to make it a viable option for more fuel conscious families that actually need an SUV.

Exactly.

Also, crossovers will usurp much of the SUV roles as they're way more efficient. Putting 2-Mode or BAS+ onto various crossovers would be a good thing for GM to do.

Ultimately, due to higher fuel costs, people will start buying vehicles they need. Those that need to handle more passengers can still buy an SUV or large crossover. Others who need less space will simply opt for something more practical.

And I like the gallons-per-mile, but then it's similar to the litres-per-100 kms we have up here. It does show how much more fuel one can save when comparing vehicles. And as the article states, not everyone wants nor can they fit into the smallest of cars.

[mikest00]

Originally Posted by mgescuro

It is smart.
I wonder how many people who bought SUV's actually need them for something reasonable like hauling a large family?

The 2-Mode system won't save the SUV.... but it will continue to make it a viable option for more fuel conscious families that actually need an SUV.

I wouldn't say you have to have a large family to need and SUV. My wife and I only have one child. Trips to Homedepot seem to warrant it alone. Hauling somehing large or mulch, plants, wood, etc. The SUV is very much needed for the "after football game lunches" and monthly scout campouts. So after the lease is up on the 06 I will be getting an 09. A 2-mode would be nice. And I seriously doubt the SUV is "dead". It may not be in as much of a demand, but I remember it being around before it was mainstream (70's,80's). SUV"s will find their niche.

[bcjohnso99]

"rating cars at gallons-per-mile may be more useful"

The metric system uses liters/100 km.

Sounds dumb at first but it's really easy to see how much a change in mileage or gas price impacts your pocket.

[O_Z]

Originally Posted by bcjohnso99

"rating cars at gallons-per-mile may be more useful"

The metric system uses liters/100 km.

Sounds dumb at first but it's really easy to see how much a change in mileage or gas price impacts your pocket.

I don't see real difference
It same kind of smart change like dropping Cobalt or Grand Am name

PS I grew up in country which uses metric system

[jbernie]

Of course it would also help if all vehicles could turn the engine off when at stoplights etc etc, if the average fuel economy for the entire USA went up 1 or 2 mpg the savings on gas would be massive.

Then again there is also that whole issue surrounding needs. I could buy a very fuel efficent vehicle to replace my pick up truck but then again that might mean I would need to make 70 trips in my small car to do what I can do in one trip with my truck.

Obviously if you are single, live where there is no snow, do not go on trails, do not need to tow anything etc etc, then a Tahoe might not really be what you need.

[JM9777]

Originally Posted by bcjohnso99

rating cars at gallons-per-mile may be more useful.

I've always supported GM's strategy of placing the two-mode hybrid system in trucks and SUVs, as improving fuel economy of the lowest-performing models will save more fuel and money than improving the fuel economy of compact cars. If we measured fuel consumption (gallons per 100 miles), instead of economy (miles per gallon), this would be obvious.

Tahoe - 14 mpg - 7.14 gal/100 mi - $28.57/100 mi (at $4 per gallon)
Tahoe Hybrid - 21 mpg - 4.76 gal/100 mi - $19.05/100 mi
Savings of 2.38 gal or $9.52

Corolla - 28 mpg - 3.57 gal/100 mi - $14.29/100 mi
Prius - 48 mpg - 2.08 gal/100 mi - $8.33/100 mi
Savings of 1.49 gal or $5.96

Trying to explain this to the uneducated (especially Toyota apologists) is like talking to a brick wall.

[TJ95GAGT]

Originally Posted by JM9777

Trying to explain this to the uneducated (especially Toyota apologists) is like talking to a brick wall.

Fortunately for those Toyota apologists its not hard to compare Prius sales vs. the 2 mode Tahoes to us GM fans.

I applaud GM for their efforts with the 2 mode Tahoe I really do, its amazing ( or a discrace, depending how you look at it) that it gets the same or better city MPG than some of GM's midsize cars. However I think they are missing the automobile demographic (and there for sales) that is affected the most by high gas prices. People dropping 50k on a new vehicle are not worried to much(yet) about high gas prices.

[Hunid Racks]

I understand the effort behind the trucks and SUVs getting the two mode but some consideration should be given towards putting the system in vans. There are thousands of vans that make their living doing shuttle work.

[CaptainDan]

Originally Posted by O_Z

I don't see real difference
It same kind of smart change like dropping Cobalt or Grand Am name

PS I grew up in country which uses metric system

The metric aspect doesn't matter.

What "bcjohnso99" was saying, is that mpg empasizes the MILES as the variable - if I get better fuel economy, I get more MILES to a gallon.

If you rate fuel economy as gallons per 100 miles (gallons per mile would be a fraction) then the emphasis is on the fuel used - if I get better fuel economy, I need less fuel to drive the same distance.


If you compare two vehicles, the miles you can go per a set amount of fuel matters less than the fuel used over a set distance. Because I have a certain SET distance I need to drive. To work, to school, to the store, etc....those distances don't change if I get better fuel economy, the fuel used DOES.

mpg is an INDIRECT measurement of fuel economy.
gp100m is a DIRECT measurement of fuel economy.

[CaptainDan]

Originally Posted by TJ95GAGT

Fortunately for those Toyota apologists its not hard to compare Prius sales vs. the 2 mode Tahoes to us GM fans.

I applaud GM for their efforts with the 2 mode Tahoe I really do, its amazing ( or a discrace, depending how you look at it) that it gets the same or better city MPG than some of GM's midsize cars. However I think they are missing the automobile demographic (and there for sales) that is affected the most by high gas prices. People dropping 50k on a new vehicle are not worried to much(yet) about high gas prices.

In addition, the problem of higher gas prices isn't just about the fuel. It's MONEY!

If my fuel costs are up by, say $2000 a year, then my next vehicle needs to save me that money. I could get a vehicle that will use less fuel, thus saving that money.

Or, I could get a vehicle that costs $2000 less. Same net result.

Getting a vehicle that saves me $2000 in gas, but costs that much (or even more) isn't a savings. That approach isn't "efficient".

[thehemi]

Originally Posted by jbernie

Obviously if you are single, live where there is no snow, do not go on trails, do not need to tow anything etc etc, then a Tahoe might not really be what you need.

If you can afford it, and its what you WANT, by all means, drive it...

[thehemi]

Originally Posted by CaptainDan

Getting a vehicle that saves me $2000 in gas, but costs that much (or even more) isn't a savings. That approach isn't "efficient".

I have heard from some people who want to offset the fuel costs
of their gas guzzler by getting a *second* more efficient vehicle.
I'm guessing they didn't do the math to see how much more that
could end up costing them instead of just using the $ for the gas.

[thehemi]

Originally Posted by CaptainDan

If you compare two vehicles, the miles you can go per a set amount of fuel matters less than the fuel used over a set distance. Because I have a certain SET distance I need to drive. To work, to school, to the store, etc....those distances don't change if I get better fuel economy, the fuel used DOES.

mpg is an INDIRECT measurement of fuel economy.
gp100m is a DIRECT measurement of fuel economy.

My car gets 20 MPG (or 5 gal/100 mi).
Let's say that I drive 40 miles per day.

40 / 20 = 2 gallons
40 / 100 = 0.4 * 5 gal/100 mi = 2 gallons

Unless I'm driving in 100 mile increments, that's twice as much work!