EPA to fix busted MPG calculations. Prius screwed.

[Tornado]

Vehicle Mileage Estimates Get Real
Ratings for '08 models, especially hybrids, will drop in new EPA tests.[/B]
That 55-mile-per-gallon hybrid car you've been eyeing may end up being a 44-mpg hybrid if you wait for the 2008 model.

The federal Environmental Protection Agency announced a new system Monday for evaluating fuel economy that will lower mileage estimates for most vehicles.

On average, vehicles rated under the 2008 method will post a 12% drop in city gasoline mileage and an 8% decline in highway mileage, said Bill Wehrum, the EPA's acting assistant administrator for air and radiation.

With the new testing requirements, the EPA is attempting to come up with estimates that more closely reflect the real-world mileage motorists can expect when they purchase a vehicle.

Under the current system, which has been in effect since 1975 and was last changed in 1984, actual mileage is often far lower than the posted EPA ratings.

Hybrids will be hit harder because the new test eliminates some of the all-electric driving that helped them produce impressive results under the present system, Wehrum said.

For the first time, the EPA also will require estimated mileage to be posted on medium-duty pickup trucks, vans and sport utility vehicles — behemoths such as the Ford Excursion that weigh between 8,500 and 10,000 pounds.

Such vehicles have been exempted from the ratings because they were considered commercial trucks. But as growing numbers of Americans adopt large SUVs and pickups as family vehicles, environmentalists and others have called on regulators to require mileage information for them as well.

Automakers won't have to publicize the big trucks' mileage estimates until the 2011 model year, however. The EPA did not explain the three-year delay but typically gives manufacturers substantial lead time when applying new regulations.

A recent study by automotive information website Edmunds.com found that the average mileage for passenger cars and light trucks was about 14% less than EPA estimates.

In part that's because the agency's current test doesn't include much stop-and-go traffic or lead-footed acceleration. Air conditioners — notorious for lowering mileage by sucking up engine power — aren't turned on, and all testing is done under conditions that simulate a 70-degree environment.

The new system will use more high-speed driving, partly in 20-degree cold. Air conditioning will be on some portion of each driving cycle, and there will be more stop-and-go and rapid-acceleration driving.

The mileage for gas-electric hybrids probably will be 20% to 30% lower than present estimates for city driving and 10% to 20% lower on the highway. These vehicles quickly lose their all-electric advantage when operated in cold weather or quickly accelerated, Wehrum said.

"This is all about providing more and better information to consumers," he said.

Toyota Motor Corp., which makes the popular Prius hybrid, now rated at 60 miles per gallon in the city and 51 on the highway — a combined rating of 55 mpg — supports the changes.

"This doesn't change the car or the technology, just the way the mileage is calculated," said Ming-Jou Chen, spokeswoman for Torrance-based Toyota Motor Sales USA. "It makes the estimate closer to real-world numbers, and we fully support that."

Moe Durand, a spokesman for Mitsubishi Motors Corp., which is bringing one of the first 2008 models to market in the U.S., said he was "quite pleased" with the averages cited Monday by EPA officials.

Environmental groups applauded, too.

The EPA "did an excellent job" with the revisions, said Russell Long, executive director of the Bluewater Network, the San Francisco-based environmental group that sought the changes. The new procedures can help motorists save money and reduce pollution by providing more accurate mileage information for them to use in their car-buying decisions, Long said.

"We're thrilled with it," he said.

The new system seems to be one that even auto dealers — notoriously sensitive to anything that could hurt a sale — can get behind.

"It won't have a big impact," said Fritz Hitchcock, whose Hitchcock Automotive Resources of Puente Hills owns several Toyota franchises and a BMW dealership.

"There's such intense comparison shopping on the Internet that people will know all about the changes" before ever setting foot in a dealership, he said. "And in the end, people find a reason to buy what they want to buy" regardless of mileage estimates.

Automakers are working on a plan for 2008 models that come out in 2007 that will enable shoppers to see the new fuel economy estimates and the mileage ratings that would have been attached to the vehicle under the present system.

As part of the new approach, the EPA redesigned its fuel economy window sticker.

It will provide a range of mileage for competing vehicles; estimated city and highway mileage for the vehicle displaying the sticker; the vehicle's estimated fuel costs for a year, based on 15,000 miles of driving; and a caution that gas mileage will vary based on driving conditions and driving styles.

The new EPA mileage estimates won't harm automakers' ability to meet federal rules requiring an industrywide average fuel economy of 27.5 miles per gallon for cars and 21 mpg for sport utility vehicles, pickup trucks and vans.

Those requirements are part of the corporate average fuel economy program run by the Transportation Department.

Link.


It about damned time. The current system was far too outdated to really be useful, and hybrids showed that in spades. Also, I think the push for light duty truck inclusion is a good thing. Now all that needs to be done is a redefinition of CAFE standards.

 

[YSSMAN]

Good news is that it seems they have thought it through just a bit, and may go on to prove that some cars are better (or worse) than what we thought in the EPA testing. Maybe with these updated numbers, people will care to get an education about the ways in which they should drive their car for fuel economy instead of the way they want to.

IMO, all we need to do now is loosen up the restrictions on diesels, and I'd be very happy indeed...

 

[Poverty]

I always did say that the US system of measuring MPG was majorly screwed

 

[Tornado]

I always did say that the US system of measuring MPG was majorly screwed

Yes you did. But for the wrong reasons.

 

[Poverty]

Yes you did. But for the wrong reasons.

I had no reasons other than it being too high, especially for certain vehicles.

 

[eg6_dude]

The US system sucked. In order to actually achieve those numbers you would have had to be the world's best fuel conserver, drive behind a huge truck where ever you went, and have to get out and push your car up hills manually!

 

[ExigeEvan]

Good, I hope they adopt the changes over here aswell.

I always did say that the US system of measuring MPG was majorly screwed

You do realise right that the British MPG quotes are just as inaccurate? You'd have to do very well to actually meet the quoted MPG with most cars.

But then again, it could just be that you haven't realised that British and American gallons are different...

 

[G.T]

You do realise right that the British MPG quotes are just as inaccurate? You'd have to do very well to actually meet the quoted MPG with most cars.

110% agreed. We know for certain some figures are quite impossible to meet at all. Tops in a Honda Civic Diesel is claimed 64.2mpg, yet the best we've ever managed is 50, and that was being ridiculously careful. I almost literally laughed when the dealer said you'll be getting around 60mpg and 50 with the petrol models when we asked the differences between them both.

The Jag, on the other hand, we were nearing its top claimed figure after driving on the motorway constantly at 70mph for 2 hours, as 40.4mpg - and still was rising. The claimed is 46.5.

So, I just think it varies a bit, but most of them are quite unrealistic indeed...

 

[niky]

But then again, it could just be that you haven't realised that British and American gallons are different...

Ahhhh... those were the days.

You've got to know something is wrong when US EPA figures rate the Civic as 2 mpg more fuel efficient than the Fit, when Honda owners here say that the Fit goes at least 5-10 mpg better than the 1.8 Civic in daily use. Whu?

I'm finding the Euro figures just as bad... and even more inflated, in some cases, even considering that Imperial Gallons are smaller.

 

[Poverty]

Good, I hope they adopt the changes over here aswell.


You do realise right that the British MPG quotes are just as inaccurate? You'd have to do very well to actually meet the quoted MPG with most cars.

But then again, it could just be that you haven't realised that British and American gallons are different...

who doesnt know that us gallons are different to british ones

British figures are however a little more realistic and I have come across alot of people who say they can get better MPG than claimed if they are driving carefully, but it ranges from car to car.

I mean some US figures stated that certain SUV's would get as good a MPG as some cars

But then when that same SUV got tested in europe, going by their figures that wouldnt be a case.

On a whole if you buy a car in the UK that says it can do 35mpg you will most likely be able to achieve that, if not better it.

 

[ExigeEvan]

On a whole if you buy a car in the UK that says it can do 35mpg you will most likely be able to achieve that, if not better it.

Yes, if you drive alone, with the windows closed, the AC off, no wrench kit in the back, nothing heavier than a silk scarf for luggage and only using the least amount of revs possible.

 

[YSSMAN]

I don't really have a good car to compare between America and the UK on fuel efficiency, as you guys rate fuel mileage quite differently than we do. I did notice that you average your fuel figures on Whatcar, and Top Gear was no good for what I was looking for (Corvette).

...Hmmm. Odd...

 

[Poverty]

Yes, if you drive alone, with the windows closed, the AC off, no wrench kit in the back, nothing heavier than a silk scarf for luggage and only using the least amount of revs possible.

not necessarily. Plenty of cars like ive said get better MPG than quoted. You also need to make sure you arent trying to achieve combined rated MPG figures when your mostly driving around town etc.

I can achieve the figures quoted for my old vauxhall with ice in the trunk and a mate or two. I can do the same with my dads car.

Ask your parents how they get on with their car, there are plenty of members here so lets see if we can all get figures and see how realistic official figures are.

 

[ExigeEvan]

Ask your parents how they get on with their car, there are plenty of members here so lets see if we can all get figures and see how realistic official figures are.

My parents measure fuel efficiency in the time it takes between fill ups

My Dad's old 1.4D AX would take about a month to run out (short daily journeys, little luggage, only gradual inclines), Guessing about 60MPG.

The Previa gets filled Weekly. Probably does abot 25mpg, at best. (A fair amount of motorway and dual carrageway, but, lots of excess generally, and we live on a hill* so not great.)

*This doesn't affect my dad MPG because he travels along the hill on his route rather than up and down it.

 

[G.T]

^^ Yep, we work it out that way too. In-car figures aren't entirely accurate - usually overestimates a few mpg - so we do it that way.

I'll list the ones I remember:

2.0 Mazda 6's claimed best 47.1mpg - our best 39mpg
3.0 Jaguar X-Type's claimed best 36.8mpg - our best 27mpg (pretty poor)
2.7 Diesel Jaguar S-Type's claimed best 46.5mpg - our best 40.5mpg
2.2 Diesel Honda Civic claimed best 64.7mpg - our best 49.8mpg

 

[fyfee]

Is there a site where I can type in Litres per 100km, as we use here, and convert it to MPG?

I could do it the other way but theres to much work involved

EDIT: Found one. And why is there a difference between US MPG and Imperial MPG?

 

[YSSMAN]

I believe a British gallon is 20% larger than an American gallon, however the measurements for miles are the same. So once you figure out the liters per kilometer, then you get the lovely task of converting their MPG figures to American ones.

On the whole, I believe they are fairly similar once you get down to it, however given that most Americans travel at highway speeds (55-80), generally the target range for MPG designs in this country, many of us may get higher fuel economy on average... That is, with a comparable car of course.

I know my Jetta is rated at 24/30 (city/highway), and I generally average about 27-28 MPG every week. I could probably drive a bit slower, but with only 115 BHP on tap, you've got to work the pedal a bit to keep up with traffic.

 

[Tornado]

British figures are however a little more realistic and I have come across alot of people who say they can get better MPG than claimed if they are driving carefully, but it ranges from car to car.

My dad's car can get 10MPG over what it was rated for. He has gotten deep into the 40's highway with it. It was rated for (I believe) 35.
I've heard of diesel Golfs going deep into the 50's, when they are rated for 44 highway.
It goes both ways on both systems. In fact, the EPA has lists for people who have gotten higher figures than there cars are rated for.

 

[Poverty]

Woops I use in car figures for my dads car, so are those invalid?

 

[Sage]

It seems like these days everything gets about 25 mpg (assuming you’re not driving one of the extremes, like a Hummer or a Prius). If you’re in an underpowered, fuel-efficient car, you’re more likely to be giving it more throttle to keep up with traffic; if you’re in a really powerful, not-so-efficient car, you’re usually going to be using only a fraction of your engine’s power. So everything seems to always even out to about 25 mpg. Generally speaking.

 

[YSSMAN]

Woops I use in car figures for my dads car, so are those invalid?

Are you talking about what the computer tells you that you are getting? I'd assume that they would be more accurate in most circumstances, as it is what the car is actually doing.

...We use the computer in our Avalanche quite often to figure out the MPG. We've managed to max it out at nearly 24 MPG a time or two (rated 14/18 highway), but on average she does about 16 MPG... Which really isn't too bad for a full-size SUV/Truck.

I still calculate my MPG in the Jetta the old fashioned way, checking the figures when I fill up, doing the math on my cell phone. Between 27 and 28 MPG is the average, and a lot of that comes from low-speed, high-traffic driving. But if I was to look at my computer (my '96 doesn't have one), I'd imagine that I could max it out upwards of 35 MPG on some days... My record has been 33 MPG back and fourth on a trip to Chicago.

 

[Sage]

I used to use an Excel spreadsheet to keep track of my mileage (since even a trip to the nearest grocery store is a 15 mile drive, and 25 miles to the nearest shopping center), but now that I’m in college I drive so little that I really couldn’t care less about my mileage (I only filled up my tank twice this quarter).

Seriously, make yourself a spreadsheet – it saves a lot of time. Just plug in the figures and boop!, it’s there.

 

[TopHat]

Based on my figures, my moms 2004 Hyundai Sonata gets about 27 to 28 mpg on the Highway, so thats just about right with the EPA, but on the other hand, my dads Mazda 6 falls short of those estimates by 2 or 3 mpg on the highway. I'm gonna draw this up to a tourquier engine in the Sonata, it just seems much more relaxed when in a lower gear and under heavy acceleration. The 6 has a more high strung pitch, and is a little more wheezy than the engine of the Sonata. Thats just my opinion though.

 

[niky]

I've only exceeded my car's EPA highway figure (14 km/l) once... on the highway, on a 300 kilometer trip. Of course, the first time I did that trip, I got the same as the EPA city figure with balls out 200+ km/h driving (10 km/l), but in daily use, I hardly ever get near the city figure.

RE: trip computers... they're not accurate enough... there are factors that they can't take into account... add to this the fact that they're also limited by speed sensor accuracy, and the figures can be misleading. They're good, though, for finding the proper cruising speed and rpm for conservation.

The best way is still to top up, record your odometer reading, empty it out, then top up again and record elapsed distance. If you're really picky about it, you'll gauge your odometer error against highway markers (mine's around 1%, non-standard tires) and correct with that in mind.