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EPA's Gasoline Efficiency Tests Provide No Valid Information At All (hotair.com)
schwit1 writes from a report via Behind The Black: The tests the EPA uses to establish the fuel efficiency of cars are unreliable, and likely provide no valid information at all about the fuel efficiency of the cars tested. Robert Zimmerman reports from Behind The Black: "The law requiring cars to meet these fuel efficiency tests was written in the 1970s, and specifically sets standards based on the technology then. Worse, the EPA doesn't know exactly how its CAFE testing correlates with actual results, because it has never done a comprehensive study of real-world fuel economy. Nor does anyone else. The best available data comes from consumers who report it to the DOT (WARNING: Source may be paywalled) -- hardly a scientific sampling. Other than that, everything is fine. Companies are forced to spend billions on this regulation, the costs of which they immediately pass on to consumers, all based on fantasy and a badly-written law. Gee, I'm sure glad we never tried this with healthcare!"
Perform a study and publish your results.
It is an apples to Apples comparison.
I doubt the Test cost Billions, unless you are covering the 70's
The EPA does what congress tells it to. There is not way they can do a scientific study without money.
Could the EPA actually drive the cars in cities and highways and see how many gallons of gasoline were consumed over how many miles?
"Companies are forced to spend billions on this regulation"
Well, not VW...
Linux, you magnificent bastard, I read the fucking manual!
Stupidly editorialized summary. On one hand we have complaints about big government but then saying they should have done more studies (wonder what side of this "debate" won't fund studies). A whole bunch of links to shit websites. I don't remember anyone claiming government standards are a perfect analogy to the real world but they do offer an excellent standard to compare different models and manufacturers against and a fair comparison to legislate against.
first, we all know there's a reasnonable correlation between epa estimates and our observed results. It's quite good. Second there's been lots of tests on other standards to show they perfrom good real world estimates. The author is nit picking that a specific set of linear combinations of tests hasn't been correlated. That is if you have 5 test that are correlated with real world measurements and you average them it is true that the average has not been tested but logically we can estimate it's error from the other tests.
who writes this crap
Some drink at the fountain of knowledge. Others just gargle.
The article makes a glaring error when it says "When the EPA tests for CAFE compliance...". EPA does no such thing...EPA tests for the numbers that go on window stickers. CAFE testing is the responsibility of NHTSA, not EPA. Some may think this is nit picking, but I find it hard to take this article seriously if the author is not even aware of who does which testing.
The gas mileage numbers that the EPA requires on new car window stickers are not determined the same way as the gas mileage used for CAFE fleet efficiency regulations. The former isn't perfect, but is a lot closer to real world performance than CAFE is.
I'm disappointed that this was posted with such a ridiculous assertion in the headline. Are you kidding me? Certainly the tests aren't entirely accurate, and I've complained about them, but saying that there's "No Valid Information At All" is bogus. Obviously you can go to the fueleconomy.gov site and see that there's a correlation between big, heavy, overpowered cars using lots of fuel and smaller, lighter, lower-powered cars that sip gas. The EPA has updated their tests a couple of times, most recently around 2007 following controversies that the Toyota Prius didn't achieve real-world fuel economy as good as what was on the window sticker. They also didn't try to factor in air conditioning or other features that are now common on cars.
The original 1970s-style tests produce numbers about 30% better than the end result today (an adjustment around 1985 reduced MPG numbers by about 15%, and the second one around 2007 brought it down by another 15%). Notably, government fuel economy tests in Europe and Japan still have ridiculously optimistic figures, so U.S. figures are much, much more accurate and reasonable compared to other places around the world.
Are EPA figures perfect? No. I personally think they went a bit too far in the most recent adjustment, since my (pre-dieselgate era) 2006 VW Jetta TDI gets MPG figures almost exactly matching what it originally had on the window sticker when I bought it.
And if this is all about people expecting to get super MPG when driving at 90 mph all the time, just stop complaining. That's not an appropriate expectation for what you should get out of these tests.
No idea what Behind the Black is but their claims are grossly exaggerated rubbish!! All of the five cars I have owned over the last 15 years have gotten within a few percent of their EPA highway ratings on the highway--when driven reasonably, at the speed limits, and in normal weather. People who are too stupid to understand that if you drive with a lead foot, are in extreme stop-and-go-traffic, are driving against a headwind, etc., will suffer mileage losses, really should keep their mouths shut because they simply advertise their stupidity.
I'm on the internet, so you can trust what I say.
Slashdot editors: how did this garbage get posted here? Why not go straight to the quoted Wired article with the hyperbolic title?
Interestingly, that article contradicts itself: "a 2013 Consumer Reports study tested more than 300 cars, and found 90 percent landed within two miles per gallon of their EPA-approved ratings."
Yeah, testing standards aren't perfect. That doesn't mean that the government is incompetent and is trying to fuck you.
Click bait, EPA and even the manufacturers say "your results may vary".
"I'm a victim" crap is really getting old. Epa mandates are reactionary because essentially for years, GM in particular, the big three gets whatever they want. I should know I gave 38 years of my life to them. Still remember my dad installing seatbelts in 1957 Bel Air because he was an extremely intelligent Chemical Engineer who ignored politics for his family's well-being. My millennials friends, remember why these regulations exisit in the first place.
The EPA test is run at low intensity/throttle. The turbo is designed so it won't kick in during the test. As long as the turbo isn't spooled up, the engine isn't using much gas. On the road, under real world conditions, you get good performance, but the turbo causes the engine use lots of gas.
I'm not a car expert. This is what was explained to me. The person was in the auto industry, but may have been confused.
To those thinking the EPA should just drive the cars, even that won't actually get very accurate results. Real-world fuel efficiency depends on so many factors that it would be impossible to reliably and accurately measure them all. For example, so-called hyper-miler enthusiast employ driving techniques to maximize their fuel efficiency. Conversely an aggressive driver could easily drop fuel economy in half. Then we have differences in temperatures, altitude, and terrain across the country.
So with that in mind, I think the current, 40-year old testing regime is probably still our best bet. It may not tell you how much fuel economy *you* will get, but since it's done under very controlled and consistent circumstances, it can give an indication to you how it will do relative to other cars. Honestly that's the best we should expect.
I fear we're going to meet the same problem with "real-world" emissions testing. I don't know of any car out there that can meet standards all the time. Take the cleanest car and get it to accelerate up a grade and it will dump pollutants. Or punch it off the light and you'll dump a lot more NOx and particulates than if you accelerate at a more reasonable rate.
In short, "real-world testing" is fairly meaningless. The only way to actually accomplish this is to have sensors and recorders on every car all the time and measure it and average it over time (and after the fact).
Still remember my dad installing seatbelts in 1957 Bel Air because he was an extremely intelligent Chemical Engineer who ignored politics for his family's well-being. My millennials friends, remember why these regulations exisit in the first place.
Good point. Are people going towearing seat belts just like the Anti-vaxxers refusal to get their children vaccinated?
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
It's Government. What the fuck do you expect?
Adding Government to any process just increases inefficiency, waste and overall cost.
Since these tests were implimented the EPA has made it clear that they are for comparison and not expected to match a given user's real world results. If you look at car ads from the late seventies and early eighties you will see the following sentence in each one: "EPA estimates for comparison only. Your milage may vary with trip length, speed and weather. Actual highway mileage will probably be less."
The EPA tests could probably use an update, but they were designed intelligently to provide useful results that would continue to be of value after unforseen technology was introduced. The Mazda rotary engine cars are a great example of this in action because they are completely unlike anything else and yet the results they get from the EPA are right where we would expect them to be, down around 20 MPG (doesn't include oil of course :p). As much as we have seen issues with hybrids, the differentiation of highway and city tests really does tackle the problem well. I owned a Honda Civic Hybrid which was the subject of a lawsuit about misleading milage ratings and I can tell you that with a light foot (which I don't have) 45 MPG highway is certainly possible to achieve. 40 MPG city is fairly believeable but I didn't do much in-town at the time.
Just to cut you off, yes I know that those are the revised ratings and that the original ratings were higher. That doesn't actually matter because the question is whether or not the numbers are useful for comparison, but in any case we are talking about the tests as they stand now.
We know exactly how that data correlates with the real world. You're going to get worse fuel efficiency than what your car is rated at. So what? They are all rated the same, so you still know for example that a car with a 40mpg rating will get better real world milage than a car with a 30mpg rating. What's so hard to understand about that?
Here's the clickbait headline/summary:
Wired: The EPA’s Fuel Efficiency Testing May Not Work. Like, at All
Slashdot: The tests the EPA uses to establish the fuel efficiency of cars are unreliable, and likely provide no valid information at all about the fuel efficiency of the cars tested.
Here's the relevant section from TFA:
Except it isn’t. The mileage reported on those window stickers? Probably fine. But when it comes to CAFE, the system is bonkers. When the EPA tests for CAFE compliance, it still uses that laughable two-cycle system. It’s got no choice: The 1975 Energy Policy and Conservation Act specifies that “the Administrator shall use the same procedures for passenger automobiles the Administrator used for model year 1975.”
Huh? CAFE is a metric covering an automaker's overall accountability on fuel economy, based on their sales mix. The window stickers are what consumers use to as an (incomplete) guide to fuel economy on vehicles they are considering for purchase (but remember, Your Mileage May Vary...). The headline is sensationalist, but the article is more nuanced. And of course, the paraphrase used in TFS is even more sensationalist: the fuel economy numbers don't provide any information at all!
Bzzt, wrong. Go read the article, not just the headline.
Worse yet is that the tests are based on 100% gasoline. But meanwhile the congress is passing laws that effectively force (or at least subsidize) the fuel companies to sell up 90% gasoline contaminated with 10% alcohol. I'm sure someone with no real knowledge about this will want to post how there is "only" a 3% energy content difference, but in my experience that is complete bullshit. You can still buy 100% gasoline if you are willing to pay a premium for it (see http://www.pure-gas.org/) but that premium is much greater than 10%, often 30% or higher. I've found that, for my 2013 vehicle, if I buy 100% gasoline that I get at least 15% better mileage, some times as much as 20% better than alcohol diluted gas. So I would be much better off if the oil companies simply sold me 9/10 of a gallon of gasoline for the price of a gallon rather than selling me 9/10 of a gallon poisoned with 1/10 of a gallon of alcohol. I would get better mileage, I wouldn't have to lug around the extra weight of the unwanted alcohol, and I could put more real gasoline in my tank, giving me a better range. But because of the political clout of some farmers in Iowa and Arthur Daniels Midland Corporation, I have to pay to have my gasoline watered down with alcohol.
And, of course, this doesn't even consider the insanity of driving up food prices and forcing us to waste grain for political reasons rather than using it for food. I'm not going to give you some bullshit about starving kids in Africa (there will always be starving kids in Africa), but I've seen prices for my own food and my dog's food (no matter if I feed him something that includes corn or not) driven up just by the extra demands for corn this stupid policy causes.
I'm an American. I love this country and the freedoms that we used to have.
RZ can say whatever he wants, doesn't mean he's not wrong. MPG estimates DO relate to reality, and many people have learned how to guess what they'll get based on the EPA figures and how they themselves drive and the conditions in which they drive. It provides an imperfect but far better than none way to compare between brands and models, something that would otherwise be impossible for consumers to do. This standard method of comparison is far more important than whether EPA figures match real-world experiences. APR is imperfect as well and is important for the same reason—it provides a standard way of comparing interest rates between products and lenders/borrowers. All he's done is ensure that if I see his name again I won't bother to read what he's written because he's established a track record of wishful thinking and faulty logic if not just plain fabrication.
There is no value in this story summary, and the final commentary is not only unprofessional it degrades the entire brand of Slashdot. These new owners don't understand what they bought.
The EPA tests were originally developed to quantify pollution generated by cars in the L.A. area, and using those tests to quantify gas mileage came later.
The EPA city cycle was not meant to represent the stop-and-go driving in Manhattan during rush hour. Rather, it was intended to be typical of an automobile trip in the L.A. area conducted on "surface streets", meaning major arterial roads that have stop lights and are not freeways. The average speed of that cycle is about 20 MPH. The EPA highway cycle was not meant to represent bombing down an open Interstate at 10-over a 70 MPH speed limit. Instead, it was to represent a trip on the 405 freeway in Los Angeles in the days before that road became a parking lot -- the test was meant to represent "moderate traffic" levels where the average speed is about 50 MPH.
Not only may your miles-per-gallon vary, the amount of BTUs in a gallon of gas can also vary downward from an alcohol-free summer blend that was probably the standard for the test -- the test conducted on rollers somewhere in Ann Arbor, MI doesn't actually measure the quantity of fuel used but instead measures the combustion products out the tailpipe and performs a mass balance with that standardized gasoline.
Taking the lower BTU fuel you may be getting into account, if you start the car engine from cold on a 70 deg-F day, don't run the A/C, and drive for about 10 miles in traffic where you average 20 MPH, you will roughly reproduce a city test, and I have found that the reading on a Scan Gauge, calibrated to tank fills, will get within 5 percent of the raw city numbers available here https://www3.epa.gov/otaq/tcld.... These numbers are considerable higher than the window sticker MPG rating available here https://www.fueleconomy.gov/. Driving on a not-that-hilly road (do this in both directions and take a harmonic average to compensate for net elevation change) on a 70-deg calm-wind day with the A/C off at a constant 55 MPH, if you can do that with angering other drivers, is a good proxy for the EPA highway test and will also get you within 5 percent.
"But no one drives that way!" someone will shout at you, and this may be true, but if you want to reproduce the EPA test conditions to see if you can match the (raw) EPA numbers, this is the way to check that.
The sticker MPG at fueleconomy.gov has had more than one "adjustment" performed to down rate it from the raw MPG. This was done because the published EPA ratings made people who considered themselves to be "good drivers" feel bad about themselves and their expensive new car purchases, and we cannot have any of that. Or rather, the "consumer" gas mileage numbers were proportionately reduced to "better reflect how real-world driving conditions on more congested city streets and with higher speed limits on highways affect mileage" whereas the Federal Test Procedure and the raw numbers for computing CAFE (corporate average fuel economy) were left the same so as to not keep changing the rules to which the car companies had to comply.
Now the down-adjusting is based on fleet averages, and your car may vary. A case in point is that Consumer Reports praised the Ford C-Max hybrid as being a lot more "fun to drive" than the Toyota Prius but slammed it for being much further off the EPA sticker in real-world driving than the Prius. Well, duh, Consumer Reports! Were you to drive both vehicles in a true "EPA city granny cycle", they probably would get proportionately higher than the window sticker as is the raw "test car" number. But left to the lead foot of a "normal driver", the C-Max with its bigger gas engine will indeed accelerate better yet use more gas than the small-engine sluggish Prius.
I also expect "eco-cars" like the Prius to suffer more from "normal driver" in relation to EPA test cycle driving because their power plants are more matched to the "granny cycle." A real "muscle car" may suffer le
at all.
"I am not a scientist" indeed.
Yeah, with the internet, there are now more partisan sources of news, which get less visits, and money. Good journalism requires lots of money. The American Public does not want to pay.
I've wondered why there are two different mpg numbers. The CAFE standard, apparently done by the NHTSA, have been around for a while, and are used for vehicle efficiency laws. Then, the EPA does a test for pollutants, and uses it to provide a relatively accurate measure of mpg. So, the villain is NHTSA, and not the EPA. But, only Congress and the car manufacturers care about the NHTSA numbers, so it doesn't really matter how wrong the NHTSA numbers are, as long as the numbers are wrong in a consistent way.
I think the problem we're trying to solve is not the right problem. The point of the EPA regulations is to encourage better fuel mileage and less air pollution. Nothing more. Would these goals be achieved by the market forces alone? Doubtful. It took the oil shock to even get fuel efficiency standards, and it took acid rain to get fuel injection that in turn resulted in the end of leaded gasoline. Neither of these were market forces, but rather responses to regulations. The world is still contaminated with the results of burning leaded fuel for nearly 60 years (1920 to 1980). Only children born after 1990 likely haven't been exposed to lead from exhaust.
To say nothing of the subtle brain damages caused by the lead in the blood stream that was passed on to children.
I know we love to cater to conservative critiques of government here, but that was not even slightly useful in the realm of criticism. If you don't like the EPA tests, then propose a better one that would be usable across all the cars sold in the US today. Yeah, there are certainly problems with it but the EPA numbers - even if they are not particularly useful on their own - can at least be useful to compare two cars to each other. They are particularly useful for some of the 4 cylinder cars out there that have wildly variable MPG depending on their configurations... compare say a Ford Focus to a Subaru Impreza and you'll see what I mean.
Damn_registrars has no butt-hole. Damn_registrars has no use for a butt-hole.
My primary criticism of the MPG numbers is that gallons per 100 miles would be a more useful number (someone else pointed this out on slashdot a few years ago). At better than 10 MPG/10 GP100M, the MPG number is perfectly adequate. Once the MPG rating gets over 20 MPG it becomes deceptive. The cost of gas difference between 5 MPG and 10 MPG is greater than the cost of gas difference between 10 MPG and 40 MPG, but most people would value the latter jump more than the former. That is, they would be more likely to buy the 40 MPG vehicle over the 10 MPG vehicle than they would be to buy the 10 MPG vehicle over the 5 MPG vehicle (in both cases assuming that the vehicles were otherwise similar...not something that is likely to happen). Or to put this another way, people are more likely to buy a 40 MPG vehicle over a 30 MPG vehicle than a 10 MPG vehicle over a 5 MPG vehicle.
The truth is that all men having power ought to be mistrusted. James Madison
Talking of the government, I think the author's sitting in a basement working for them.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
https://www.wired.com/2016/07/...
Not clicking on a link to Hot Air.
Ooh, moderator points! Five more idjits go to Minus One Hell!
Delendae sunt RIAA, MPAA et Windoze
Fuelly is probably a decent way to determine what mileage to expect. Its just crowdsourced data.
Nissan Versa 38HWY, 28CITY, average of my mostly highway100+ mile commute was around 35MPG. 92% of HWY rating.
Nissan Rogue 32HWY, 25CITY, average of the same commute, 24MPG. 75% of the HWY rating. Heck, it's only 96% of the CITY rating.
Frankly, I would of consider other vehicles if I knew the real world mileage would be that low. Also, Nissan reliability sucks. The EPA lets the car companies test and set, but doesn't hold them accountable. You can go to fueleconomy.gov and see that Nissan Rogue ratings by consumers average around 24MPG, which is far below the actual rating.
These days, computer-controlled engines pretty much eliminate the need for catalytic converters which were mandated in the 70s. Regulation never matches the state of technology.
Consumer Reports provides such feedback regarding disparity between their gas mileage test and EPA stickers only occasionally, such as with their evaluation of the C-Max. If they give a table for the cars they review somewhere in some issue as to "EPA sticker", "Consumer Reports road test", and "percent disparity", I would like to know where that table is. The impression I get is that 1) they regard their road test as a "ground truth" for fuel economy and think of the EPA numbers as "made up", 2) if a reader wanted the EPA number, they could go look it up on FuelEconomy.gov. Their road test has also changed over time, making it hard to compare a new car model against a 20-year old car, and yes, some of us keep cars that long. I can't find in Consumer Reports back issues a good description of their road test conditions.
Has Consumer Reports ever set up a road test to replicate the EPA test conditions and used that to quantify road test/EPA test disparity?
They only mentioned the disparity for the C-Max because it was large, even compared to the Prius, which also has such a disparity. The tone they took was that the larger disparity for the C-Max was evidence of Ford "gaming the system." They only mentioned in passing that the C-Max was also much less underpowered than the Prius, without any discussion as to whether this performance fully accounted for the difference in gas mileage, whether this was a tradeoff that a consumer would want to make, and whether driving the C-Max more conservatively made up for the shortfall in gas mileage.
Indeed, the large disparity in the C-Max could be evidence that Ford is gaming the system, but Consumer Reports didn't do anything to pursue this further, unlike the lab that found a disparity in the VW Diesels and dug deeper. It could be that Ford is legally gaming the system in optimizing the C-Max for the narrow range of driving conditions on the EPA test while giving it a transmission tuning making it "more fun to drive" in more "normal driving conditions", hoping that their consumers would be happier with the better acceleration and that consumers would be conditioned to believe that the "EPA numbers are made up, anyway, and no one ever gets those." Or it could be that Ford has "pulled a VW" and not get caught, but Consumer Reports has passed on investigating this deeper to find out.
Consumer Reports also appears to lack curiosity regarding outliers in their own test results. I remember a while back they tested a Dodge Neon back when Chrysler made a car with that nameplate, with a 3-speed automatic transmission to boot, that got in the mid 40 MPGs on a test where competing cars were in the mid to high 30's. Did they rerun the test as a "sanity check"? Do they even know what the variation is on their test between successive runs?
I also notice that their gas mileage rating can fluctuate, often downward, from year-to-year when they retest the same make and model of car. You also see this in the EPA numbers. Some of that may be transmission and engine retuning to trade more "pep" for less gas mileage, especially in the years when gas prices were in decline. But a consumer gets to wonder if the same kind of car can vary in gas mileage and by how much. That the expectation is that the EPA gas mileage is "made up" bakes into the system that it is hard to make the case that you bought a "lemon car" with bad gas mileage. A gas mileage complaint is really hard to make stick with the guys who sell and service your car because they will always turn it around and blame it on your driving. Did Consumer Reports ever try renting, say, about a half dozen cars of the same make, model, and year to see how consistent they are?
Yeah, yeah, Consumer Reports is a non-profit with limited resources in the amount of testing they can do. But given that gas mileage is such an important factor in satisfaction with an automobile purchase, and given that it is so hard to benchmark your car against a standard to check if you got a gas-mileage lemon
you mean that huge 5000+ lb super duty truck with the huge engine rated at 9 mpg might actually have higher mpg than the 2500 lb commuter car with the 1.8 liter 100 horsepower rated at 35 mpg? wow.
Star Trek transporters are just 3d printers.
Click bait, EPA and even the manufacturers say "your results may vary".
"I'm a victim" crap is really getting old. Epa mandates are reactionary because essentially for years, GM in particular, the big three gets whatever they want. I should know I gave 38 years of my life to them. Still remember my dad installing seatbelts in 1957 Bel Air because he was an extremely intelligent Chemical Engineer who ignored politics for his family's well-being. My millennials friends, remember why these regulations exisit in the first place.
followed by years of detroit providing us with those nonretracting clips-above-the-door for storage shoulder belts, just as a fuck-you, while the europeans were giving us retracting shoulder belts.
followed by mandating air bags originally marketed as for people who don't have their seat belts fastened, which now will kill you if you don't have your seat belt fastened.
yet the rightwingers persist in their belief that companies wouldn't market product that cause their customers to die off because it would be unbusinesslike. as with cigarettes.
Star Trek transporters are just 3d printers.