I thought I'd share a basic calculation, which I use all the time, but I thought might be helpful to those who are not as mathematically inclined as others.

I used to wonder if taking another route to work would result in better fuel efficiency. One thing to consider when asking yourself this question is, is the increase on your MFD actually worth the additional mileage?

From a monetary perspective, one could argue more miles means more maintenance costs, but let's ignore that one. Let's say the only factor in determining your route of choice is the amount of fuel it costs you to go route A or route B.

Let's use the following as an example:

Route A: Normal work route - 20 miles - 50.5mpg
Route B: Alternate route - 27.2 miles - ???

Given the above, we know how much fuel we burn each day going Route A: 20 / 50.5 = 0.3960 gallons

To make Route B equal/more beneficial [in terms of gallons burned] you must burn the same, or less gallons during your 27.2 mile trip as you would on your 20 mile trip.

To determine this, you take the total miles of Route B and divide it by the total gallons burned to get your resulting route MPG required to make it beneficial: 27.2 / 0.3960 = 68.69mpg.

So what does all that mean? In order for you to burn the same [or less] amount of fuel driving Route B, you would need to get 68.69mpg or better to make it worthwhile.

I hope this helps, I know some of you like to play around and figure out what distances will get you the best mileage, but there are also other factors to consider when trying to get the best FE.... hopefully this will shed some light.

Agreed. In fact, it is a complex relationship that also needs to include 'agnst':

A) MPG, route A vs B
B) distance, route A vs B
C) time, route A vs B
D) angst, route A vs B (does one route really p*ss you off!)

The key is to use a map to look at all possible routes and then methodically test them. Done right, it may take a couple of weeks but in the end, you'll know.

One thing I've found is driving slower works for me because it takes the pressure off. I have time to think about other things and enjoy seeing what the heck is going on around me. For example, yesterday evening I was taking my standard, fuel saving route using an access road next to the divided, 4-lane, high speed drag through town. I saw two accidents on the divided, main road including one with a dump truck at 90 degrees and in a "T" with at least one sedan. Traffic was backed up on both sides because of the obstructions and the 'rubber neckers.' Meanwhile, I just kept cruising along at 30 mph, enjoying the view.

The thing is our hybrids give us options that were never practical with gas-only cars. The way you learn about them is to test alternate paths. Some tests will be really really good and others will be awful. But when you're done, you'll know.

Bob Wilson

Operation Iraqi Oil Freedom:

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My other 1500 cc car:

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I've noticed the same thing after 'auditioning' several routes to/from work. I have the get there fast route and the alternate 'high-mileage' route. There are several others that yield exceptional mileage but just take way too long and I just don't like them. All my routes are essentially the same distance since I'm in Orange County and there are roads everywhere, so my only variables are MPG and time, and they vary inversely