Is driving for maximum mpg worth the trouble?

[wsbones]

I'm not sure oil comes from fossils. Are you?

[a priori]

Originally Posted by wsbones

I'm not sure oil comes from fossils. Are you?

I don't know exactly the reason for the question, but it prompts a couple from me:

Let's just say we don't know that oil comes from fossils. Does that make some difference? Do you think there is some indication that oil is something which is under current and constant creation within the Earth?

[F8L]

Originally Posted by wsbones

I'm not sure oil comes from fossils. Are you?

Are you an abiogenic believer or are you just playing semantics with the word "fossil"?

[F8L]

Originally Posted by a priori

F8L: I don't disagree with you. You must look at how you will drive the two cars when making comparisons. What yogadoc was pointing out, however, was the fuel economy already available through the "S" model, and if you are doing mainly highway driving, the difference, for the cost, makes for an interesting comparison.

(Edited to remove more info about the 2010 "S" I though F8L hadn't included!)

If you were mainly a freeway driver I could see the comparison making sense for sure.

[WPWoodJr]

Originally Posted by F8L

This case becomes even stronger with the more miles a person drives each year. To me 10,000/yr seems rather low.

True, the amount of money saved increases directly as number of miles increases. The point I am making is that there are diminishing returns to driving for better fuel economy. Going from 35 mpg to 100 mpg you only save 1.86 gallons/100 miles under the assumptions in the blog post. Whereas going from 15 mpg to 35 mpg, as I did by going from a 1998 Audi A6 to a 2010 FFH, I save 3.81 gallons/100 miles without even changing my driving style.

That said, my FFH mpg is now 46.2 for the current tank

[WPWoodJr]

Originally Posted by JimN

...However Mr. Blogger is going to be in for a very rude awakening when he files his 1040. He'll discover he screwed himself out of some of the tax credit because his new Ford is going to be placed in service after the transition date. He'll probably just file a fraudulent return & the IRS won't notice.

Not so, the in service date determines the tax year you claim the credit in. The purchase date determines eligibility for the credit. See the IRS web site for examples.

[donee]

Originally Posted by WPWoodJr

True, the amount of money saved increases directly as number of miles increases. The point I am making is that there are diminishing returns to driving for better fuel economy. Going from 35 mpg to 100 mpg you only save 1.86 gallons/100 miles under the assumptions in the blog post. Whereas going from 15 mpg to 35 mpg, as I did by going from a 1998 Audi A6 to a 2010 FFH, I save 3.81 gallons/100 miles without even changing my driving style.

That said, my FFH mpg is now 46.2 for the current tank

Hi WP...,

But with banks giving 2 % interest, hypermiling does better well up to about 60 mpg. Somebody driving a 60 mpg vehicle , can hypermile up to about 70 mpg with some practice. That is is a consumption improvement of 14 %. You ain't goin to get that interest, even from Bernie Madoff!!

[WPWoodJr]

Originally Posted by fuzzy1

In a mathematical sense, that curve has the same shape everywhere, from below 0.001 mpg to above 1000 mpg. Anyone claiming that there is little benefit above any point X is being tricked by the scaling of the picture. Any given percentage change in mpg yields the same percentage savings no matter where the starting point is placed ...

True, but the reason the chart is compelling is because it speaks to a range of mpg and miles per year that is normal in everyday life. Almost nobody drives enough miles per year to make 1000 mpg significantly better in absolute dollar terms than 100 mpg, so a chart showing that range would not be as interesting even though it would have the same shape.

For example, if you drove 40,000 miles per year at 100 mpg you would use 400 gallons of gas. At 1000 mpg you would use 40 gallons for a savings (at $2.70/gal) of $972 per year. I saved over $1000 (400 gal) per year by trading in my 1998 Audi A6 which got 15-16 mpg for a Ford Fusion Hybrid which gets 35-45 mpg, and I only drive 10,000 miles per year.

So, no tricks in that chart

[WPWoodJr]

Originally Posted by SageBrush

I want a 100 mpg car, so 35 mpg just makes me unhappy. 60 - 70 mpg in my Prius is tolerable -- for now.

I want a 100 mpg car too, despite my chart

[WPWoodJr]

Originally Posted by a priori

Take a look at the change from 5MPGs to 10MPGs, and THEN you'll see a difference that turns your head!

Seriously, there is a gain to be made whenever you improve mileage. When you ask whether it is worth the effort, then you are beginning to consider all of the other cost/benefit issues of life. Is it worth it to drive 5 mph faster? Clearly, going faster makes accidents more dangerous to all involved, so is it a good idea? Going faster than the speed limit not only is more dangerous, but it could be more costly in terms of speeding tickets.

I'm taking a more personal and practical look at it. I drive about 15,000 miles per year. If I get 35MPG, then it costs me $1,200 (at $2.80 per gallon). My 2007 Prius was getting me around 54MPG on a rolling 12-month basis, though lifetime was just above 52MPG. If I call that 50MPG, then I spent $840 per year on gas, saving myself $360 -- every year! That was enough to cover oil changes and new tires. Just think of the appeal of "free maintenance" when purchasing a new car!

I think my 2010 is going to be more of a 55MPG car (I have the Prius V, so the mileage won't be as high as the other Prius models). The move from 50MPG to 55MPG is "only" $76 per year, but it is still $76. Of course, when I compare it to 35MPG, I've saved $436 each year, and now I can start getting "free" mods on the car like window tint.

What does it cost me? I've spent some time reading PriusChat to learn about driving techniques, and I've spent a lot of time on the road learning to use them. I don't compromise safety, and I take advantage of the amenities available to me in the Prius V w/ ATP. My last trip of 840+ miles with 4 people in 90 degree heat, using cruise control and A/C on Auto, and driving on highways at posted speeds and (slightly) higher, produced a round-trip FE of 52.7MPG.

If I had been alone on that trip, I probably would have driven a bit differently, and it would have increased my gas mileage, but the real saver would have been the weight differential. I've done similar trips on my own, recently, and my FE has been as high as 58.8 for 441 miles. That still is using all of the amenities and driving at between 55 and 75mph. There is nothing wrong with saving a bit of money.

The post is not questioning the desirability of achieving high mpgs, its more about diminishing returns for slower driving and effort expended.

To get 45 (Today I'm at 46 ) mpg in the FFH probably requires more careful driving than getting 55 mpg in a 2010 Prius. So my question about whether its worth it to drive 45 vs 35 mpg is more for FFH drivers than Prius drivers. For 2010 Prius drivers I might have to compare 60 to 45 mpg.