The economic incentives of fuel efficient driving.

[roflwaffle]

Dave mentioned that most of us had taken this beyond what was economical and I'm curious if that's the case, so if you have the time, feel free to post up a few things. I'm going to restrict this to highway driving since city driving is really hard to compare and in most cases is probably economically worthwhile to drive efficiently because there's such a small difference in average speeds (mostly dictated by lights and so on).

So...
-What is the difference in highway mileage between what you get driving efficiently and what you get driving like everyone else?

-What is the difference in average highway speed between what you get driving efficiently and what you get driving like everyone else?

-How much do you like driving more than you like working, or vice versa?

For instance in my Camry I get ~25mpg@70mph average highway speed and ~35mpg@55mph average highway speed. This means that the cost of going faster with those two speeds is ~$13.5/hour or ~$15.5/hour adjusted for taxes. Since I like driving about three times more than I like working, I'd say I would need to be getting ~$45+/hour to make it worthwhile to drive faster. Even if I was driving something more fuel efficient that managed ~70mpg@55mph and ~45mpg@55mph I would still need to make ~$20+/hour to make it worthwhile.

Given how most people drive I can only assume they like working a lot more than they like driving, but most people here aren't the average driver, so what kind of economics are you looking at?

[justjohn]

Interesting way to look at it. I don't know if most people will agree with your take on how to decide whether it's "worth it" or not, but it makes sense to me.

I don't have comparison numbers for my "new" car though, so I can't crunch the numbers right now.

[redpoint5]

Originally Posted by roflwaffle

Dave mentioned that most of us had taken this beyond what was economical and I'm curious if that's the case, so if you have the time, feel free to post up a few things...

For instance in my Camry I get ~25mpg@70mph average highway speed and ~35mpg@55mph average highway speed. This means that the cost of going faster with those two speeds is ~$13.5/hour or ~$15.5/hour adjusted for taxes. Since I like driving about three times more than I like working, I'd say I would need to be getting ~$45+/hour to make it worthwhile to drive faster. Even if I was driving something more fuel efficient that managed ~70mpg@55mph and ~45mpg@55mph I would still need to make ~$20+/hour to make it worthwhile.

How much are you paying for gas that it saves you $13.5/hr by driving slower? At 30mpg you are consuming 2gal/hr. That's roughly $8 of gas burned every hour in my neck of the woods. Now how are you saving nearly double that by going slower?

There are way too many variables to consider when determining whether it's worth driving faster or not. Some things to consider would be the direct monetary expenditures (have to buy more fuel), value of time, environmental impacts, physical risks of driving faster or slower, etc. For the majority of people, they value not thinking of any of these things, and instead just allow their instinct to dictate speed.

For me, I travel at the fastest speed that I believe will avoid a speeding ticket 99 out of 100 times, or 72mph (whichever is slower). Life is short and driving is dull unless you are going fast. I already waste 1/3 of my life sleeping, and I don't want to waste any more than I have to driving.

Think about it this way; if you average 1hr of driving per day, you will spend roughly 15 days (24hr days) driving per year. If you spend 60 of your years as an average driver, then you have spent roughly 900 days, or close to 2.5 years of your life inside a vehicle.

[robertwb70]

I don't like most jobs and I like driving even less. I recently did one of the on line "how much is owning a car costing you" things and it costs me $195 a month for my Geo, of which $80 is fuel so only 41% of my costs are reducible by improving FE. Personally I would rather live somewhere I could do everything I needed without a car but that seems like a far fetched dream most days...

[Gasoline Fumes]

Hypermiling gives me an extra 100 miles per tank. I used to pay for those miles.

[metroschultz]

I love driving.
I should have been a trucker by trade.
To me it is ultimately about the savings.
I am a miser.
I am the electricity Nazi in my house, the water Nazi, the garbage Nazi...
you get the idea.
I HATE waste,
of any kind.
So I hyper-mile on the highway and in town.
I reuse the plastic water bottles my kids bring home,
I reuse Ziploc bags,
I bake my own bread and have a bread slicer set to 3/8 inch ( I'd go thinner, but the bread falls apart) so I get more slices and the kids eat less bread.

To answer the question;
I average 52mpg driving efficiently, before that I averaged 48mpg.
So at current prices I pay around $4.66 to drive one hour.
And before I would pay around $4.99. (using current price)
I save $.33 per hour.
The difference is insignificant. But if I work really hard, and find ethanol free fuel, I can get over 60mpg. (then the diff is around $.90) But ethanol is killing me now and I am getting lax in my habits.

[roflwaffle]

Originally Posted by redpoint5

How much are you paying for gas that it saves you $13.5/hr by driving slower? At 30mpg you are consuming 2gal/hr. That's roughly $8 of gas burned every hour in my neck of the woods. Now how are you saving nearly double that by going slower?

~$4+/gallon, same as everyone else in the states give or take ~$.25/gallon. Going with your example, lets say I'm paying $8/hr at whatever speed. I go faster and get to my destination 15 minutes sooner than I would have otherwise and also pay $3 more in gas money. So, if I go faster I pay an extra $3 to cut 15 minutes/.25 hours off of my trip. $3/.25hours=$12/hr more to drive faster. Obviously every example depends on the specifics, but the basic idea is that you get whatever mpg at whatever reasonable lower speed (~55mph to ~65mph), and when you drive faster than this you pay $X more in gas and reduce your travel time by Y hours, so you end up paying $X/Yhr=$Z/hr to drive faster.

[roflwaffle]

Originally Posted by metroschultz

To answer the question;
I average 52mpg driving efficiently, before that I averaged 48mpg.
So at current prices I pay around $4.66 to drive one hour.
And before I would pay around $4.99. (using current price)
I save $.33 per hour.
The difference is insignificant. But if I work really hard, and find ethanol free fuel, I can get over 60mpg. (then the diff is around $.90) But ethanol is killing me now and I am getting lax in my habits.

You left out how many hours more it takes you to go the same distance. According to what you said, if you are only paying $.33/hour less, then going from 48mpg to 52mpg doubles your travel time. Is this correct? Do you really take twice as long to get to your destination at the speed associated with 52mpg as you do at with the speed associated with 48mpg?

[Frank Lee]

I disregard what my time "costs" i.e. figuring I make $20/hr and it costs me $3/hr to go 55 vs 70 or some such. Combine that with me not allowing other traffic to dictate my speed, and I'm content to go 55 in a 55, 55 in a 70, or even 45 in a 65 if I'm pushing a vicious headwind. That helps fe and costs. I drive so infrequently and usually over such short distances that even if I'm "puttering" along at a pace that gives others aneurisms, I still spend but a fraction of the time motoring as the average joe, so it doesn't seem like a burden to me.

I only do mods that are free or nearly so- high tire psi, recycled coroplast mods, high state of tune, etc. but then again I tackle everything mechanical at home so lowering and whatnot I do too but at no/low cost.

It's about saving money AND the oil resource for me. So, I like E85 and displace as much regular gas as I possibly can with it.

[roflwaffle]

What's your mpg at 55mph and at 70mph Frank?