EPA's Gasoline Efficiency Tests Provide No Valid Information At All (hotair.com) 136
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!"
Idea!!! (Score:1)
Perform a study and publish your results.
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But it's easier to just rant about it online. Studies and facts are for nerds.
Re:Idea!!! (Score:5, Interesting)
Indeed, this is a pointless rant. The US uses a number of driving cycles for different purposes - FTP-75, HWFET, US06, and SC03. In terms of determining ratings that are presented to computers, US standards are by far the most stringest in the world. European cars are rated by the much less stringent NEDC, and Japanese cars by the laughable 10-15 cycle, where the highest speed involved in the whole cycle is 70 kph (under 45 mph), with an average speed 1/3rd of that.
The US cycles are regularly updated - the most recent update to the FTP-75 was in 2008. And yes, it's made them more stringent, based on... wait for it.... research on how people drive, the thing that this rant claims doesn't occur. Now, it's true that, for consistency purposes, CAFE ratings (which the buyer never sees) still use the same measure that they did back in the 70s, and that there's different measures for different types of vehicles and the like. But that's because you don't want to break your comparisons to older vehicles; anyone actually working with CAFE numbers is going to be aware of their limitations. John Smith from Podunk Arkansas isn't going to be messing around with CAFE figures; CAFE exists basically for accounting purposes, to see if the fleet is overall getting more or less efficient.
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to see if the fleet is overall getting more or less efficient
Yeah, sure, but no. There are cars no longer on the road, not because nobody wanted them, but that the Manufacturer couldn't afford to make them any longer, because they were so popular that they skewed the CAFE numbers. Cars like the Crown Victoria, a staple of Police and Taxi companies. They are prized for their durability and longevity, and now ... they don't exist.
And instead of driving Crown Vics, Police have moved to bigger, larger, less efficient SUVs and because they are "Trucks" do not fall under C
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This isn't completely true. Lots of police departments are using FWD or even RWD cars for their cruisers now: the Impalas and Chargers are both popular. The Charger is a RWD car.
Yes, there are a lot of big gas-guzzling SUVs used by police, but there's also plenty of much more efficient cars, which are a lot better than those piece-of-shit Crown Vics and Chevy Caprices they used to use. I've driven in both those things, and they were absolutely horrible cars. A modern Charger or Impala is better in every
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You have a paddy wagon.
Some people can be crammed into the back seat but the majority of police interaction doesn't require transportation of prisoners. When they do, you call in a van or SUV to pick up the suspect. Most of the paper work can be done from the cruiser so no need to have the cop return to the station for booking the prisoner.
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WTF? The Charger is a huge car, and has a back seat just like any other police car. Have you never seen one?
And if that's not good enough, call for a van like the other poster said.
I guess according to you, none of these police cars exist [allpar.com].
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Comparing a 90s Caprice to a modern car is pretty silly. They haven't made one in 20 years. The Crown Vics had gone through many upgrades over the years and were/are exceptionally durable, plus the parts are dirt cheap. This economy of scale has not been reached with any other vehicle used in modern fleets as nothing has become essentially a standard across the board like the Crown Vic was.
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I know I wasn't explicit, but I wasn't comparing a 90s Caprice to a modern car, I was actually comparing it to other 90s cars; even when it was new, it was a piece of shit. So was the Crown Vic, which I've had to drive. It drove terribly, handled terribly, the steering wheel was crooked, it had a cheap and crappy interior, it just wasn't a good car. The Caprice was huge, but didn't even have enough legroom for me at just over 6 feet. These cars were archetypes of everything that was wrong with American
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The problem is that there are multiple classes of vehicle for the CAFE standards. What we should be doing is having ONE pool of all the consumer vehicles that a company makes and requiring them to meet a standard. If that requires the company to change its mix of vehicles, and make fewer SUVs and more small cars, so be it. And if they have to cut the price of the small cars and raise the price of the SUVs to get the demand in alignment with the supply, even better.
I would put work vehicles (ones that are ac
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But there is still a legitimate argument against CAFE. You're forcing the manufacturers to produce a car with better CAFE ratings every year, but that won't always result in better ratings on newer cycles or in real world use. My new car is rated 23/32, but actually sees about 26 with my driving. Most owners can't even break 23. When driven to get top marks on a CAFE test (which I have only done once in my car on a long drive), it netted slightly over 40.
Wouldn't it be better if they focused on real-world r
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What are actual driving conditions like in Japan? What are actual driving speeds?
The last time I saw anything about driving in Japan, it was a footnote to a programme that pointed out that before you could buy a car from any Tokyo dealership, you had to present them with your parking permit. No parking place? No car. One parking place, it displays
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Best real world data is probably available from Fuelly [fuelly.com], even though it may need some clean-up for fuel type and sub-model it can at least give you a decent idea of how well a certain model fares. Unfortunately some models have a limited number of samples even there.
But actual driving data is more relevant when selecting a vehicle than the manufacturer figures even if the number of samples is low.
Research (Score:2)
Could the EPA actually drive the cars in cities and highways and see how many gallons of gasoline were consumed over how many miles?
Re:Research (Score:4, Informative)
Too subject to variation cause by the drivers. Even the weather and temperature on the day would have a huge impact. All car manufacturers would be insisting their cars were tested on the coldest, highest humidity, but no rain and no wind day.
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This is in part due to the gasoline, which has a different mixture in winter months than summer.
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To say nothing of slower drive times and idling while defrosting and/or scraping frost and clearing snow so you can see to drive.
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Drivers already do this, and there is a high correlation to driver experiences with mileage to the listed EPA mileage estimates. Sure, it's not extremely accurate and is variable based upon the driver, but it is still reliable information for the consumer. It's wrong to say there's "no valid information", which makes it seem like the EPA just makes up numbers and consumers were too stupid to verify them.
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May be something worth crowd sourcing. My 2 cars have average mpg over time displays. Set up a small site asking for car make/model/year approximate number of miles, reported mpg and a rough description on driving style (how much highway w/ cruise vs. city w/ light to medium traffic vs city w/ stop and go). After enough entries for a particular make/model/year it should be pretty easy to see just how off the EPA "as advertised" numbers are.
FWIW my 2013 Nissan Versa is reporting 39.3mpg average over the p
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Sure, it's not extremely accurate and is variable based upon the driver, but it is still reliable information for the consumer.
Which is why at base, I have a pretty good idea that a car with a higher sticker mpg will get better gas mieage than one with a lower sticker rating.
What the EPA test really measures (Score:5, Interesting)
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... [epa.gov]. These numbers are considerable higher than the window sticker MPG rating available here https://www.fueleconomy.gov/ [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
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What Consumer Reports knows and when they know it (Score:2)
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 re
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Well duh, consumer reports knows this!
Latent Heat gives a nice informative post with facts, figures and links, and you totally demolish it with a superbly timed:
Well duh
The kind of insightful incisive post that is becoming the norm for Slashdot
and Youtube comments.
Come on - you can do better.
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Absolutely not.
You need the same route and the same driving pattern for the comparison to be meaningful.
In an actual city, traffic comes and goes. A route may be unavailable for months due to construction. And real-world driving is inherently reactive since you have to deal with other drivers. There is no way to put each vehicle through the exact same trial.
Basically, it is impossible to have a controlled environment in a real city. But you can drive on testing grounds following a pattern with stops, starts
LOL (Score:5, Funny)
Well, not VW...
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Software development isn't free...
wtf is this shit? (Score:1)
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.
Factual error (Score:5, Informative)
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.
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EPA, NHTSA, they're all government, right?
The times they are a changin... (Score:2)
Talking of the government, I think the author's sitting in a basement working for them.
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EPA MPG != CAGE MPG (Score:5, Informative)
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.
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Thanks for the details on that.
So CAFE is kind of like our Unemployment Rate; not really a good indicator of anything, but it's a consistent baseline to compare a bad standard from year to year.
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So CAFE is kind of like our Unemployment Rate; not really a good indicator of anything, but it's a consistent baseline to compare a bad standard from year to year.
In the US, the Unemployment Rate is manipulated regularly to make things look "not as bad". The real number that people should look at is employed labor. That number has been dropping steadily since its peak in the 80s, IIRC, and is now hovering near 60% of the labor force.
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I was curious, and looked it up on the Bureau of Labor and Statistics [bls.gov] website. If I'm reading that right, Civilian Labor Force, Employed, Percent of Population peaked in 2000 at 64.4%, which is 5% higher than 2000 levels.
Looking at the wikipedia definitions [wikipedia.org] (especially that third image), I think the interesting metric is the employment-to-population ratio [bls.gov] (i.e. all employed people over all people, eligible to work or not). That default view does show a 5% drop since about mid-2008 that never recovered. It
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Employed labor is a percentage of the total population that is employed, but doesn't correct for those above and below the working age. The only people who push it are people who want to reinstate child labor and those who think people should never retire.
The correct stat to use is the U6 - The unemployed and under employed stat.
Re: EPA MPG != CAGE MPG (Score:2)
Except that stat is also subject to dropping people out of the pool. If you're unemployed more than some amount of time, they consider you no longer part of the labor pool.
The numbers shouldn't be cooked. A raw percentage of working-age adults (perhaps with a breakdown by age group) that are employed and their full/part-time status would be far more useful than the numbers we get.
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I suspect it's a combination of an aging society and a depressed job market. I love the definition of "labor force" given by the Department of Labor.
"People who are neither employed nor unemployed are not in the labor force."
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Neither are supposed to measure real-world mileage.
A useful test needs to be standardized, and doing so while accounting for 'real world' conditions becomes difficult and even more expensive than the existing system. The best you can hope for is that they have some relative correlation with fuel efficiency from car to car. Its easy to criticize and point out flaws in the existing approach, but try proposing a test that is repeatable, standardized, and reflects real world conditions. And make sure you are very specific about exactly what you will measure, wh
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I think the OP is showing an agenda; "Government can't do anything right." Well, there is a lot of inefficiency at various government agencies, they aren't all the same.
There are sometimes some stupid regulations, but we need SOMETHING to improve gas mileage. The EPA was getting defunded and staffed by hacks during the Bush administration. I'm pretty sure "funding" for regulatory agencies has not been an easy sell since then. But damn, I need the EPA and FDA to function because I need to breathe and I need
This is a rotten assertion (Score:5, Informative)
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.
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The assertion appears to be, basically, that we're spending a lot on enforcing it, but not on doing a formal study where we follow a bunch of cars around and see what the MPG actually is in real-world conditions--which actually feeds into your own complaint about the most recent adjustment, since that sort of study would provide empirical data on what the correct adjustments ought to be. You might find out that things like that the adjustments ought to be different depending on the manufacturer, because th
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Nerds can comment on the technological hurdles in parameterizing a standard test that would have to apply with equal margin of error to a wide variety of devices (cars). Compare bench testing.
It's also widely reported that the EPA numbers for MPG-e are somewhat dubious and hard to correlated to various EVs but it's a pretty good rule of thumb.
I dont think nerds should be confined to rebooting their PCs or building the next kernel.
I think we have aptitudes reaching out many aspect of lives.
As for your not wa
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"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!"
The focus is redirected sharply from technological discussion to political diatribe near the end of the submission. I'm a chemical engineer with longtime experience in the fuel industry. As such I fully agree with your statement that nerdiness is not constrained to computers. However, I believe the right-wing rhetoric is distraction from technical discussion, as evidenced by the large fraction of non-technical replies to the post which instead address the pol
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Points taken. It initially sounded as a wider "political stories being submitted to /." to my second-language ear.
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"Breaking news from a conservative viewpoint" (Score:5, Informative)
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.
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That doesn't mean that the government is incompetent and is trying to fuck you.
It is only incompetent if it fails to do so.
But that wasn't a summary up there, it's an editorial, and it is election season, so you know, it's a story for the human torch. How many gallons does he burn an hour?
Re:"Breaking news from a conservative viewpoint" (Score:4, Insightful)
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The best available data comes from consumers who report it to the DOT [wired.com] (WARNING: Source may be paywalled)
Why not go straight to the quoted Wired article with the hyperbolic title [wired.com]?
Those are the same link. And when viewed through Firefox Tracking Protection, with no specific ad-blocking extensions installed, the text of said hyperbolic article is as follows (screenshot [harvard.edu]):
From the p
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Re: "Breaking news from a conservative viewpoint" (Score:2)
This is demonstrably false. I am old enough to remember living in places where pollution was bad--air quality in the urban US is substantially better now than it was when I was a ki
Turbos (Score:2)
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.
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I thought Turbos increased efficiency more than they reduce it. They should in most cases - they are reclaiming some of the otherwise lost energy from exhaust gas...
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Yes. Turbos should give you more power per unit of gas. All thinks being equal.
Running during the EPA test you are off turbo, low rpm, low horsepower - say 50hp. You are less efficient, but you are not using a lot of fuel. In the real world, on turbo you are higher rpm, higher horsepower say 250hp. You are more efficient, but you are using a lot more fuel.
The key while driving to getting the EPA's published number is keep acceleration low enough that the turbo doesn't kick in. If you allow the turbo t
Definitive real-word testing not possible (Score:3)
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).
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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).
There's nothing inherently wrong with that, though. Most of us are already having our mileage recorded by our insurance company every six months. It hardly seems an awful violation of privacy if someone also recorded our fuel consumption. It might be a reasonable way to carbon tax vehicles without having to put a GPS on the vehicle. You would need a meaningful speedometer correction regime to get good numbers without GPS, though. One way to do that would be a road-facing optical sensor, which can be install
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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).
There's nothing inherently wrong with that, though.
Huh? Nothing wrong with that? Perhaps you might reconsider. At what point do you draw the line on people tracking your activities? Driving? Walking? Brushing teeth? Personal bathroom time? Need I continue?
Most of us are already having our mileage recorded by our insurance company every six months.
What insurance company are you using? I've seen the progressive insurance ads but no one I know has told me about allowing an insurance company to put a GPS tracker in their car for mileage, distance, speed, areas traveled, etc. nor the perks from doing so. There are much better insurance companies
This is silly (Score:1)
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
Slashdot editor FAIL. Wired editor FAIL (Score:1)
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) gui
worse yet (Score:2)
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/ [pure-gas.org]) but that premium
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Nitromethane is even better for squeezing power out of a small internal combustion engine. Some people running on nitromethane get more than 8000 HP out of a pushrod V8, and they don't need any cooling system at all.
Therefore, everybody should be using top fuel in their cars.
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For longevity, reliability and power, E85 is a really the best way to go.
Not very helpful criticism, there (Score:2)
My primary criticism of the MPG numbers (Score:2)
Non-wingnut link (Score:2)
https://www.wired.com/2016/07/... [wired.com]
Not clicking on a link to Hot Air.
Yup...totally inaccurate (Score:2)
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 c
Catalytic converters aren't necessary either (Score:2)
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.
what? (Score:2)
this is stupid (Score:5, Insightful)
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
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Re:this is stupid (Score:5, Insightful)
first, we all know there's a reasnonable correlation between epa estimates and our observed results. It's quite good.
I've always thought so. You have some manner of baseline, and you go from there.
And the concept of some sort of magick number of miles per gallon is silly anyhow. Is it for me, who tends to drive like a granny, and who gets very near the EPA figure, or is it for the person with a lead foot that leaves their vehicle idle when they go places, never shutting it off.
My old Jeep Grand Cherokee, got around 5 miles per gallon better gas mileage when I drove it than when my wife did. She's much more agressive a driver than I am, and drives faster overall.
My new Jeep and her present Jeep are almost identical, but once again, I get better gas mileage in mine.
So when you have people complaining that they don't get anywhere near the sticker MPG, its usually a good clue that they aren't driving in an economical fashion And then for the folks that think the ratings are bad, who is right? Am I wrong because I get very much the mileage the sticker say, and my better half is right, because she doesn't?
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Yeah, more than that. Factory MPG is set with 100% gasoline, whereas US gas stations are forced to dispense somewhere between 10-15% Ethanol which results in a 4-8% reduction in MPG. Factory MPG is set on flat tracks at a highway speed of 50 mph and a city speed of 35 mpg. They also average it out as 55% city and 45% highway, which matches almost no one's driving pattern. I can just barely beat the factory highway MPG of my 2006 Subaru Outback (23 city/28 highway) but only by hypermiling and 75% highway. Th
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I don't know, I managed to beat the highway mileage for my Grand Marquis by 2 miles per gallon while traveling at a cruise control set 77 mph. I don't do real city driving but around town and country roads average 2 miles per gallon over the combined city/highway rating. I don't have the lead foot I had in my 20's and 30's anymore but I don't dawdle even though I no longer feel the need to launch at every light.
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I don't know, I managed to beat the highway mileage for my Grand Marquis by 2 miles per gallon while traveling at a cruise control set 77 mph. I don't do real city driving but around town and country roads average 2 miles per gallon over the combined city/highway rating. I don't have the lead foot I had in my 20's and 30's anymore but I don't dawdle even though I no longer feel the need to launch at every light.
Yes - the difference between different drivers makes any idea that a person will buy a vehicle and get the exact mileage written on the sticker impossible.
I would hazard a guess that the type A people who probably have more agressive driving habits are also the people who would want to think there is an exact gas mileage figure that can be used.
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Re:this is stupid (Score:4, Informative)
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Oh please. I routinely beat the EPA figures on my 2015 Mazda, just by driving relatively conservatively and at lower speeds. Any "normal human" can match EPA figures, they just have to stop driving like an asshole and flooring it every time the light turns green.
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I routinely get 3+ mpg higher than my highway EPA estimate on my 2014 Hyundai Elantra, and I'm not exactly the most reserved driver, but I know what not to do to jeopardize my fuel effeciency.
As you said earlier, it's all about a baseline. If you buy a car that's supposed to get 20 mpg on the highway based on EPA figures, you shouldn't be surprised when it comes time to fuel up.
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You need to modify her Jeep's throttle so it's less aggressive. This can be done with a microcontroller, modifying the outputs of the throttle pedal. Do it very slowly, so she doesn't notice.
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You need to modify her Jeep's throttle so it's less aggressive. This can be done with a microcontroller, modifying the outputs of the throttle pedal. Do it very slowly, so she doesn't notice.
hmm. just sleeve down part of the air inlet tract, smaller and smaller. again, do it gradually.
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Yeah exactly. The idea is to change what the ECU perceives to be the driver's throttle inputs. So with my microcontroller, I can apply a non-linear profile, so it still seems like the vehicle has good pickup from a standstill, like when driving in a parking lot, but if she floors it it'll only seem like 75% throttle to the ECU, and at other mid-range throttle positions, there'll be less response.
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Re:this is stupid (Score:5, Informative)
Was this summary written by the oil companies who want to get rid of the EPA or what? It is grossly misleading if you actually read the wired article.
The Hot Air (never heard of it) article is cherry picking the information they want to make the EPA look as bad as possible. Taking "CAFE dates back to 1975" and turning it into "The law requiring cars to meet these fuel efficiency tests was written in the 1970s" is grossly misleading when the statement is followed by " And by 2008, the standards were better; 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."
90% of cars being within 2 mpg seems reasonable to me.
I understand there are some issues with the fleet-wide tests, but those aren't really what matter to consumers and they are still leading to improvement in the environment which is the goal. I am not worrying about acid rain today like I had to as a child. Fracking aside (which the EPA isn't allowed to regulate), water is mostly safe to drink compared to prior to the Safe Drinking Water Act. The EPA is a very very good thing. I like having air that I can breath and water I can drink.
Slashdot editor FAIL.
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Hot Air is a pretty well known anti intellectual fact free zone that actively promotes the idea that climate change is an illusion perpetuated by the devil.
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Hot Air is a pretty well known anti intellectual fact free zone that actively promotes the idea that climate change is an illusion perpetuated by the devil.
"Hot Air is the leading conservative blog for breaking news and commentary covering the Obama administration, the gun control debate, politics, media, culture" if you can't trust the leading conservative blog for unbiased insightful reporting on matters of science, then who can you trust? the vastly wealthy and powerful climatologist cartel?
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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?
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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
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