I know, it's an old post, but I had to reply. There's a good reason it's all done under controlled conditions. The idea isn't really to tell you exactly what fuel economy you'll get, but rather to establish a stable comparison method for ALL cars, so that you can say the following:
- car A rated 25 mpg hwy
- car B rated 35 mpg hwy
- car C rated 30 mpg hwy
"I wonder which car will give ME the best mpg's on the highway?"
The sticker isn't saying you'll get 35 mpg's with car B, but rather that car B will most likely give you the best fuel economy on highway drives. People are so dense lately that they can't understand that there are so many different variations in driving styles and conditions that there'll never be a test that matches the results 99% of drivers get number-for-number. But by using a standardized test you can at least say car A < car C < car B for most people on the highway, and make an informed decision. That's also the reason for the area on the new labels that says "most people will achieve between xx and xx mpg."
We can do the people are so dense they dont understand what it means....but as well car companies are designing cars to perform great in the controlled test, but in RW environment to fail due to RW condititions. So the average customer gets a Nox I4 (prime example), and reads that it gets xx city, combined 26, and 32 Hway. When they get on the interstate, put cruise @ 70-75mph...expecting one thing, but getting something completely different is a concern. You can state its used to compare, but that is not the case. Being the conditions are so controlled in the EPA testing (if they are even tested, alot of times the manufacture provides this information). The EPA needs to better design its test to correlate to real world conditions so true comparsions can be made between cars. The model they use is flawed, being its not to real world conditions. This happens alot with the company I work for, we design a product, put it through the test machines which simulates real world conditions, performs great...Go through a marketing plan to launch product, its pushed out the door (everyone back at corporate does a high-five)....We get the product, put it into real world conditions...and the STOP signs come up because it does not perform as expected/stated or designed. Lack of proper testing, lack of considering real world conditions and different environments has a huge effect on consistent results. Do I expect a winter/summer number and it be super defined...No, but what I would expect is true numbers taking into account coefficients of drag/frontal area and TRUE driving speeds in this country. Not a 60mph max, no A/C, controlled fuel that nobody else can get. If this was the case, the Nox I4 would've never passed the mustard for being rated 32mpg on highway. It does great around town, but once put up to normal highway speeds, weight, drag and frontal area come into play, causing those numbers to drop dramatically.
