http://www.wired.com/news/autotech/0...w=wn_tophead_1

Looks like hybrids are far from the holy grail they have been marketed as lately.

 

All this suggests OEM's might be making hybrids (and other cars as well?) designed to do well on the EPA's MPG test w/o as much regard to actual observed economy.

 

This has been discussed extensively for a long time. Fact is, ALL cars fall short of their advertised EPA rating. Its the way EPA does their testing, this isn't limited to hybrids only by any stretch.

The thing with hybrids is, it is very easy to see the EPA rating come from a hybrid vehicle if you just acquire a few sensible driving techniques. Like looking ahead for stop lights so you can coast to a stop earlier, don't always jump the gun as soon as the light turns green, and find a sweet spot where your burning leaner rather than richer. Doing this, I saw gas milage levels well above EPA ratings in my Insight. I was averaging about 62 lifetime MPG, also getting a few 100 MPG trips in while the EPA rating for a CVT Insight was 56/55 MPG. Doing this, I can also meet EPAs numbers in the Z28, but I can never seem to surpass them as well as I did in the Insight...

Also, a lot of these people claiming that their vehicles are falling short of EPA ratings live in the snow belt. You get considerabley less gas milage in cold weather than you do in warm weather. Don't ask me why, I don't know. I think its the block staying at cooler temperatures even while running. In the winter I saw about an average of 45-50 MPG and in the summer it was around 70 MPG.

 

Cold air is is heavier than warm air (sinks and compresses) and because of this it is more dense. More fuel is required to mix with the increased air density to avoid a lean condition.

 

How you drive definitely has a big impact on mileage. I actually average 22 MPG in my 2002 Monte SS daily driver with EPA rating of 19 MPG. If I had a hybrid, I'm sure I'd do worse than EPA figures as it would require putting your foot in it much more to get acceleration (I know the Monte SS ain't fast by any means, but it's for sure faster than a Prius). I've seen articles where testers were able to achieve close to the EPA figures in a Prius, but it sure as heck wasn't driving the way people really drive.

 

Still, having to adapt your driving style just to meet, or even come close to, the EPA MPG estimates is kinda lame. There's 15 year-old honda CRX's that are getting that kind of gas mileage or better! My old 89 Toyota Corolla averaged close to 35, with an occasional trip over 40MPG. And that wasn't babying it, that was driving like I normally would not paying attention to MPG or whatnot.

 

Hybrids tend to do "really well" in the EPA tests because they have a lot of stop and go driving and low speeds (55mph and below). These are conditions that hybrids do especially well in... but in reality we drive much faster and accelerate quicker.

BTW,

Normal cars get an EPA rating, then the EPA multiplies it by a "fudge factor" lowering the effective MPG by some percentage to represent the "real world economy". This is what goes on the window sticker and it is why you can often exceed the EPA ratings if you drive easy on the throttle. Also of note: The CAFE averages are based on the higher MPG number before the "fudge factor" is multiplied in.