Slashdot Mirror
EPA Fuel Economy Myth: Too High, Too Low?
ThosLives asks: "I have seen here on Slashdot , and just about every other publication, numerous articles about fuel cells, hybrid vehicles, and the inaccuracies of EPA fuel economy stickers. For instance, today there is a review of the Toyota Prius that had the famous line 'Since no car really achieves the EPA estimated mileage...' I happen to drive a car with an EPA sticker of 21 city 25 highway (all figures in miles per gallon). I've driven the car for 47000 miles and the lowest I've ever seen is 23 and some change; the highest, 36.3 (I'm probably about 60% highway 40% stop-and-go and yes, the high was on a long highway trip). My all-time average is about 28.5. As most people get less than the EPA mileage, how does the Slashdot readership fare when it comes to EPA sticker vs actual experience, and on what type of vehicle?"
"Am I a rare breed that can drive my car (2.0L I4, 170 HP, 6-speed manual) aggressively (I've had coworkers and friends say 'woah!' more than I'd like to admit *grin*) and still stomp the EPA sticker? Did I get lucky with a phenomenal car? Am I enough of a counter-example to thwart the belief that the EPA figures are 'too liberal'? Are fuel economy issues just FUD from [insert lobby group of choice]? Or is the answer simply 'it depends on how you drive, what you had for breakfast, and the color of your neighbors' cat?'"
Of course, MPG greatly depends on how you drive, the state of the car, the fuel, the weather, traffic, and terrain.
The EPA numbers are a relative guide. They won't tell you exactly what you'll get for fuel consuption. However, you can easily use the EPA numbers to compare two cars' relative fuel efficiency. In fact, I submit that there is no better guide available for cars sold in the US.
(I've had coworkers and friends say 'woah!' more than I'd like to admit *grin*)
Ye who speeds, cuts people off, and winds through traffic, is the first to reach the red light.
Candy-Coated Knowledge
The whole system should be dumped in favor of vehicle choice, not artificial limits put on cars by the government.
The truck exemptions (that allow for SUVs to have pretty much any fuel economy [or lack there of]) came from the late 1970s when most trucks were used by farmer and construction workers. The idea was to help those people, who generally are involved in small business and make peanuts anyway.
Times have changed, now everybody and his brother has an SUV or pickup truck (even if they don't admit it). The regulations haven't changed, not because of a scam, but because the federal beaurocracy is a mess. Sure, the oil-loving administration isn't going to hurry along any changes, but they aren't doing anything actively to prevent such changes either.
Toyota doesn't mess around. They've also sold the hybrid technology to ford. Let's not forget that toyota is also releasing a hybrid which does 0-60 in 4.03 seconds and tops out around 155mph. Don't walk away from this thinking Toyota is maniacally evil, if anything, they've got their shit together more than most automotive companies.
Sorry for being a toyhead, they please me immensely. Something tells me, if the author of the article was driving a volta, miles per gallon would be the least of his worries. I think toyota pretty much tops the list of fuel economy, on any playing field. Prius wins in my mind, not strictly because of fuel consumption, but by the name that's behind it.
Or you can dispense with the notebook altogether if, like me, you always fill your tank fully at the gas station.
When you fill up, the pump will tell you how many gallons you just pumped into your car. When I get back into my car, I reset the tripmeter (the "second" odometer which can be reset) after noting the number of miles I've driven since the last fuel stop. Then it's just a matter of spending the next minute or so trying to do the division as accurately as possible without getting into an accident.
This method is certainly no better than what the parent recommended, but it definitely requires less paperwork.
I also feel the need to say that there are a lot of very serious things that can go wrong with your car that don't affect the fuel economy --- just because you're beating the quoted fuel efficiency rating doesn't mean you don't have to look at other things!
They also depend on what gas you put in the car. Some cars do drive better on supreme.
When I used to live about 400km from my hometown, I spent the first while driving home on regular, it took about half a tank to get there (45L tank?)
However, when on a whim I tried "Supreme," it actually took me just a little over a quarter... so milage and bang-for-my-buck was actually better on the more expensive gas. Possibly this also has to do with the mountainous terrain and the fact that the gas gave me more power - not sure.
I do know that I regularly stick injector-cleaner in, so I shouldn't be getting plugged there. Therefore, I'm willing to state that better gas can give you better milage (and not all gas stations give the same quality gas either)
Everyones mileage will vary. This is for one very good reason. The mileage of your car is determined on a chassis dynometer running the federal driving cycles for city and highway. The current cycle is the LA77 I belive. That would be a cycle designed in 1977 as if you were driving around in Los Angeles California. So every car is based of a very set driving. Obviously no one will ever drive just like this. Some peoples driving will get poor mileage some great just on their routes they drive.
The other factor is indeed how you drive. I drive very agressively, but at the same time I get good mileage. Why is this? Well largly because I have worked on projects getting getting highmileage for years, Futuretruck. I understand what the car is doing and what to do to run it where I can get the best mileage. And often if your driving right, you will get good mileage, since making the most of your car and its potential is a very similar thing to how to get good mileage, conserving energy and so forth. Its not how powerful your car is, it's how you drive. A professional driver can roast a fool even when driving much less of a car then the fool.
Also driving a POS car with no power for years got me good at making the most with little power, so now I don't need to use it all to do what people do with more power. People are often shocked with how my car performs when with me driving, and they have the same car.
The driving cycle the gov uses is just simply out of date, but even a upgrade won't fix the problem do to as stated, people drive differant in differant places. If you live in the mountains on dirt roads, well your won't do as good. But if you live in kansas and your area is paved, your going to do better.
Also as car become more varried in what they can do and their drive trains, (gasoline with an auto, vs say a powersplit hybrid with a turbodiesel) the model is going to be harder to fit.
Also models vary so much. Look at any one model but then look at how much you can change with options. You can had 500+ lbs to an SUV just optioning it from the base to the top end with all the power features and such. So even in a model you get lots of differance, even if the engine and tranny are the same.
And yes I'm sure many people will say my 19xx gets this many miles per gallon but my new one gets far worse. Yes this is true, but thats because makers have tossed mileage for emissions, which is a very good thing, and in doing that cost some mileage (aside from CO2 the other emissions are not directly linked to mileage, sometimes you hurt mileage to reduce emissions). Also new cars are so much safer to do more structure and such. Your 80s Japanesse cars were tin cans, they had to add a lot of weight to make it safe.
Things also apply to trucks vs cars. Most people who buy a truck/suv find that it gets better mileage then listed, few will get under 20mpg, just that the fed test isn't freindly to trucks, and some people are just morons and can't drive a truck and get good mileage. But for that there is the inverse and people who drive econobox's and don't get crap for mileage and no where near what it's listed to get.
If you get in mid 20s mpg with anything, be ok with that, into the 30s, great. For most people the differance doesn't relate to much money saved. Hell, if you buy a bottle of water out of machine, or a coffee at starbucks everyday you wasted more money then the differance in your cost driving to work that day.
Altough, around 2 months ago I performed a 'test'.
During the whole tank of gas, I accelerated as slow as I could never pressing the gas more than 1/4 of the way. I knew the lighs were going to turn red, so why accelerate? I eased on slowly and came up to the red using as little break as possible (a waste of energy)... maybe even rolling into the light as it would turn green and _then_ slowly accerlerating.
On the highway, I would stay in the right lane (insane for me). The speed limit is 70, but I would hold 63.
For the tank I averaged 35mpg.
Moral of the story. The car you choose does have a lot to do with your final MPG. But your driving habits also have a huge amount to do with your fuel usage.
I get twenty kilometers per litre, that's about fifty miles per gallon, on average, and that's with a very ordinary turbodiesel, nothing fancy or especially fuel economic (and a pretty quick driving style).
Essentially, nothing. The problem is that people are buying the hummer and other SUVs as car-replacements. That means not only are they getting around in them on a day-to-day basis, but they are also driving them like they drove their cars: fast, hard, and with overdue maintenance. Larger, less efficient vehicles become even more inefficient (not to mention dangerous) when driven hard. Since the hummer is considered to be something of an off-road vehicle, it probably doesn't lose huge points on efficiency in that area. However, since most people are not using the hummer for its claimed intended purpose, it is grossly inefficient, but not shockingly more so than other, similar vehicles. I have a friend who drives a Durango as if it was a sports car and he gets about 8-10 MPG. Basically, a big part of the whole gas consumption problem is not just the vehicles but also how they are driven. We are going to need large, gas-hog engines for the foreseeable future to drive trucks and heavy equipment, but when those engines are overused in personal vehicles, those vehicles need to be thought of as trucks instead of as cars.
I am feeling fat and sassy
Man you gotta get laid, quit drinking, or do something to loosen up. I'm so sick of people blaming SUV's for all the world's problems.
Look around your home. Everything is made from plastics nowadays, and plastics come from petrochemicals. Carpet, shoes, jacket, tv, CD's, DVD's, chairs, aspirin bottles, backpack, remote controls, lampshade, joystick, keyboard, mouse, just to name a few. Are you old enough to remember when softdrinks all came in glass botttles, or do you think they always used plastic?
Our demand for all things derived from crude oil has increased, not just gasoline. Even natural gas was burned off as a waste product 30 years ago, now it's used as a fuel and new supplies are required to keep up the demand.
If everything you own is a hand-me-down or a reused item, and you don't drive, heat your house with wood and not oil or gas, and you don't purchase any new plasticy consumer goods, then your preaching has merit. If not, and I suspect this is the case, stop being so ignorant and don't give me your higher and mightier than though SUV's-are-evil speech. You're contributing to the demand for petroleum products just as much as anyone else is.
According to Time Magazine, gasoline accounts for 44% of US oil consumption. Diesel fuel, heating oil account for another 19%. Plastics procution is buried somewhere in the "other products" category, which accounts for only 15%. So while I can't say off hand exactly how much petroleum is used for plastics, I CAN say that at least about three times as much is used for gasoline.
Look, you're right that it's a multifaceted problem. Probably heating and electricity production (in which oil plants play a non-negligable roll) are even bigger concerns than plastic; however, gasoline is the largest single contributor.
More over, gasoline consumption is probably one of the easiest areas in which to make significant improvement. Unless you build your home or make major, costly, renovations, efficient heating and cooling can be fairly difficult. There are some simple things you can do, but you can only make so much headway. Electricity consumption is much the same situation, and effecting how it's produced is a more long term project.
On the other hand, it's quite easy for most people (who don't need to do major hauling for construction or farming) to buy a vehicle with nearly twice the fuel efficiency of many SUVs, so realistically this is the best way to attack the problem in the short term on an individual level. So, to me saying "oh what about plastics and heating, etc." still is a pretty flimsy excuse for making such a wasteful choice."You call it a new way of thinking; I call it regression to ignorance!" -- Operation Ivy
Also, you might check out the Ford Escape (a hybrid SUV) that will be coming out next year. 40MPG ain't bad for an SUV! Check out this article, for example.
My buddy is an off-roader, and I go with him occasionally. I've seen the H2 in action, and trust me, it can't get out of it's way. I've seen one basket ball player, and one foot ball player, each driving his own H2, on two seperate occasions.
We had to winch both of them out with his K5 blazer (which is now painted on the side "H2 RESCUE TEAM".)
The H2 has the same transmission as many many many chevy vehicles, geared identically. How come they don't get 10MPG? The H2 is designed to be a gas guzzling, curb sitting POS, so people with more money than sense can look down on the commoners.
Constitutional rights may be respected, repealed, or modified; but they must never be ignored.