I've been meaning to comment on this for some time now and wanting to seek the opinions of those who are driving hybrids since they might see the most significant change in EPA estimates. (window sticker that is) Although nothing will really change as to real world numbers, the perception for first time buyers could be a good thing or bad thing. What's your take?

The EPA is planning new fuel economy tests that will affect 2008 model year vehicles. Rating on the window stickers of hybrids like the successful Toyota Prius will most likely take the biggest hit. Hybrids will look far worse than they are currently being advertised ... according to some automotive experts, up to 30% worse.

The familiar window sticker labels have long overstated vehicle mileage according to most research and is acknowledge by the US Environmental Protection Agency. The sticker tends to make most vehicles look more fuel efficient than they actually are. The new plan is to incorporate testing that will more accurately portray what a 'real world' drivers are most likely achieve.

In the case of hybrid vehicles like the top selling Toyota Prius it is going to be a significant change. They have often taken heat from buyers for what has seemed an overstatement of 60 mpg in the city. According to Toyota's own David Hermance an executive engineer, most owners are getting between 42 and 48 miles per gallon. Athough unlike the lukewarm reception to this change by many hybrid advocates, Mr. Hermance believes that "any improvement in customer communication is a good thing."

Some of the changes that seem to affect hybrids more than conventional vehicles are because the new numbers will include items that were not part of the original 1985 standards. The new 2008 EPA figures will now take into account the use of air conditioning and factor in acceleration. Other areas ignored by the vintage EPA numbers were the affect of cold weather which can take a toll on real-life mileage. Overall, vehicle stickers on conventional gas powered cars and trucks will also take a hit ... about a 5% to 15% hit for highway driving numbers according to EPA Administrator Stephen L. Johnson. He commented that they are attempting to bridge the gap between what the sticker estimates and the fuel economy drivers are getting in the real world.

As with the Prius, other hybrids by Ford, Honda, etc will most likely reflect a 20% to 30% lower estimate for city driving and 5% to 15% lower for highway driving . Another contributing factor is that highway speed limits have changed since 1985; people on the average drive faster, use air conditionering which degrade fuel economy in all cars, but affect the most efficient hybrids in a big way.

The coming change is nothing new, as the EPA has been considering revisions to the calculations for several years. It has consider eliminating the separate city and highway numbers and at one time looked into replacing it with one combined figure. They polled consumers and the response was that they were use to the 'city' and 'highway' designations and didn't want to see a change. What the responses did indicate though was consumers just wanted more accurate numbers. Four proposed new labels can be seen on the EPA's website. The proposed regulation will remain open for public comment for about 50 more days ... so now is your chance to be heard!

Although most automaker are uncomfortable with any change, they agree that some modification is long overdue. A concern for those who are environmentally focused and desire automaker and consumer to opt for more efficient and clean cars, is that these new reduced numbers on the most efficient hybrids will discourage the implementation of advanced hybrid technology.

--RichC --- "My Desultory Blog" & CinciTDI Club

I will be dissapointed if the highway rating is decreased as the Prius actually does manage to get 50 MPG at highway speeds below 65 MPH (slightly lower at 75 ). The present city rating of 60 is only achieved in very special circumstances and should be reduced to the mid to high 40s. My actual lifetime MPG is 46 (mostly highway, but cold weather hits hard on the few short trips ).

JeffD

I like the D label with the bar graph of other vehicles in the class ... reminds me of the EnergyStar comparison on home devices. I think they need to look towards sites like this for the upper range you may be able to see on hybrids as not to limit them to traffic light drag racers, but the conservative drivers as well. I think they are trying to make the label very simple, and they shouldn't have to. The public is smarter than they beleive, and that could be something the dealer explains to them if they cannot understand on thier own.

I have met someone who has a lifetime average very close to 50 mpg, and they have never hypermiled. They are 'older' (60's?) but they just drive conservative. Thier son was getting 35 mpg until he came to the realization that coasting to lights and a lighter acceleration would make him happier with the car, then he jumped to 45 mpg. Otherwise he uses a/c (always on), the only other things was pumped up tires (to 50 psi). It really isn't as hard as they make out to get the numbers unless you are 'hot rodding' it constantly, or get a really bad set of traffic, live in a hilly area without the ability to conserve momentum, etc. worse case scenerios.