So I didn't understand before about gallons/100 miles. In my mind improving MPG from 10-15 was the same as improving it from 50-55 in terms of saving you gas money. I see now the fallacy of my thinking! But, this has me wondering: Is it nearly pointless to try to wring extra efficiency out of something already so efficient? My wife drives the opposite of hypermiling. Zooms off the line, screeches to a halt. She drives a Subaru Tribeca that is rated 21mpg or so. She uses a *lot* of gas. I'm in the Prius hypermiling. Wouldn't it make more sense to put her in the Prius where even if she drives like a maniac she pretty much can't help but get very respectable mileage and I drive the Tribeca and hypermile it where I don't mind doing it (she HATES it) and I'll get a much larger family bang for the buck? We drive similar commute distances so it's not like I'd be adding a ton of miles in the worse MPG car. But overall, why bother trying to wring 5 more mpg if you are already hitting 48-53 without too much effort? It's literally a few bucks every 1,000 miles. Tribeca? A lot more than a few bucks.
Yeah, I didn't come to the realization until I'd read the article I linked to at http://priuschat.com/forums/other-c...eage-no-its-your-gallonage-really-counts.html and ran some calculations myself. The people who drive guzzlers are the ones who should be trying using LRR tires, keeping their tires properly inflated, trying to hypermile and reducing useless idling. Unfortunately, those drivers are highly unlikely to do most or any of that, let alone even measure their mileage. :/
Cwerdna, it was YOUR post linking to the C&D article (that you just linked again) that actually got me started on learning about GP100M, so thank you for that!
Your wife is using a car to increase her time efficiency. Her objective is to maximize her functional abilities by spending as little time on the road as she can. Hence, your wife is focus on being quick first - fuel efficiency is a secondary goal if it is on her radar at all. My guess is that she drives a Suburu Tribeca AWD SUV because she like the higher driver position (to see ahead of he road) in heavy traffic, she carries alot of cargo, she speeds because she has a tight schedule, and like all wheel drive because she's driving on bad road conditions or dirt roads.... Hypermiling can to extend the fuel efficiency of the highly fuel efficient Prius as much as 20% , i.e. 50mpg to 60mpg - but the equivalent fuel saving of 3.33 gallons per 1000 miles is small as you pointed out. You correctly observed that increasing the fuel efficiency of your wife's less fuel efficient 21 mpg SUV by 20% to 25 mpg would lead to a more significant fuel savings of 7.6 gallons per 1000 miles (47.6 gallons - 40 gallons). While hypermiling cost has practically no monetary cost it does require time - something your wife cannot or may not want to give up. I think you should suggest to your wife that she test drive some of the more fuel efficient SUV-crossovers like the Mazda CX-5 (sister of the Ford Escape) or a Hyundai Tucson 6-Speed Auto FWD (sister of the Kia Sportser) or a 2012 Prius V - so when gas prices jump over $5 per gallon those options will be in the back of her mind - and it will be her decision.
The already good mileage of the Prius does mean that you are saving less gasoline for a comparable amount of hypermiling. On the other hand, the Prius is designed to take maximum advantage of hypermiling efforts. Were I you, I would try the experiment of switching cars and see for yourself. Hypermiling is always worth doing, and the whole time saved argument is overblown. The difference (in a Prius) between full acceleration (middle of the power band) and Wayne Gerdes's 86 MPG method amounts to about 7 seconds per stop light. It is like getting paid $32 per hour on your commute.
I agree with Walter and Corwyn. For me, the difference in hypermiling saves about $300/yr. but I drive 35k or more a year. If I only drove 10k a year I'd probably say to hell with it, slap on some 17" wheels and drive normally. LOL
I drive pretty efficiently, my wife does not. The interesting detail is that I cannot think of a single instance when she arrived at a destination before me in those cases we took two cars. I hesitate to say I 'hypermile' because of the connotations. I prefer to say I have good driving habits. It is true though that it takes some effort and practice before good habits become second nature. Sort of like turning off lights in the house when I leave the room. I drive a Lexus CTh these days, rated by the EPA 43 city, 41 highway. The Lion's share of my driving is highway at 65ish mph, but I have had the car long enough to say that my habits lead to the following: 53ish mpg on the highway 60 mpg on rural roads traveling about 55 mph 60 - 70 mpg in my city of Albuquerque Do I save a lot of money ? I don't really ask that question; I am a 'waste not, want not' kind of guy. I also tend to think of the effect of my behaviors if they were widespread. They are not, of course, but that is not an excuse to act like others.
