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Hybrid Cars to Get New Mileage Ratings
Posted by
samzenpus
on Mon May 14, 2007 11:22 AM
from the creative-math dept.
from the creative-math dept.
Skidge writes "Wired is running a piece showing the drastically reduced mileage ratings for hybrids after the upcoming changes in gas mileage calculations by the EPA. While the cars themselves aren't changing, plugging these new numbers in to the equation makes a hybrid much less cost effective: "The two top-selling hybrid vehicles, the Prius and Honda's Civic Hybrid, will lose 12 and 11 miles per gallon respectively from their city driving estimates." The new values come from more realistic testing; the old, over-inflated ratings were higher in part because the cars idled a lot, allowing the hybrids to completely turn off their engines. The new ratings should be more in line with what hybrid drivers are actually seeing."
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Sampling? (Score:5, Interesting)
It's important to have accurate mileage ratings on cars, and it's hard to understand how the EPA could be so bad at it. Why do they try to estimate instead of just sampling?
Here's a simple approach: When a car comes in for an oil change, read the mileage rating stored inthe on-board computer and upload it to an EPA database. Problem solved.
Re:Sampling? (Score:5, Insightful)
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Re: (Score:3, Informative)
Many cars are driven around in "normal situations" by test drivers. Many car magazine photographers do their best to try to get snaps of these cars.. They could use the data from these cars to do their estimates. For cars that aren't test driven, they could start.
My car (an '07 Caliber) was rated at "28 to 32 MPG". I consistently get 26 or less.
Re:Sampling? (Score:5, Insightful)
Manual or Stick? Driving habits effect the ratings. Do you drive 65mph on a 65mph freeway or do you drive 75mph-80mph? Do you accelerate fast? Do you find yourself braking often? Think about it the next time you approach a stop-sign. Does your foot move from the accelerator directly to the brake when you want to stop? Or are you 'coasting' and letting your momentum slow you down before you start to brake? Do you speed quickly the the next red light just to stop, or do you slowly coast to it, even if all the other cars are 'rushing' to the red? Do you drive with your windows down or the air-conditioner on a lot (it creates more drag or needs more energy to use)?
I bought a 2006 Pontiac Vibe (new) and just recently a 2007 Toyota Corolla (both awesome cars, though, I do wish the Vibe had a little more 'pep'). The Vibe was rated at 28-36 MPG if I remember right. I'm currently getting ~35MPG (mostly) highway (though it was closer to 31 MPG in the winter). The Corolla (while only having it for about a month now) is getting about 38 MPG (mostly) highway.
Both of these are manual "stick" transitions. The fiancee drives the Corolla, I drive the Vibe. While I don't usually drive aggressively, I don't pussy-foot the cars when accelerating to highway speeds (winding out the RPMs pretty high). However, I do kick in the cruise control at speed limit speeds, occasionally 5-over. What I do try to do, and what I'm getting better at recognizing, is that I try not to 'waist' energy by having the car do more than it needs to do, particularly in braking. Lets put it this way, the more you use your brakes, the more energy you're waisting. (which is the theory behind Hybrids, to turn the brake heat/energy back into car energy). Better braking habits will not only help save some gas but also extend the life of your breaks.
If your car is significantly getting much lower MPG than the rated amount, I would 1st) get it checked out by the dealership. 2nd) look at your own driving habits. If you're getting 26 MPG and you do pretty much all city driving, then I would say you're right on schedule (You can usually take off 1-2 MPG from the rating for 'real' estimates). If you want to raise your MPG, take a longer route in the city that makes you stop much less frequently. Stop/Go is the hardest on an engine and your millage efficiency.
Cheers,
Fozzy
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Re:Sampling? (Score:5, Informative)
Some anecdotal evidence of mine... I drive a '93 Dodge van with over 220K miles on it. It has an onboard computer that tells me both instantaneous and average MPG, so I decided to experiment.
Driving "normally" I got 11.3 MPG average over two weeks. Then I started using cruise control, whenever possible, set at the speed limit. Coasting whenever possible (I'm never in a hurry to get up to a red light anyway), not accelerating as hard and trying to avoid accelerating up hills. My next two-week average was 14.7 MPG.
Since my average commute is a little over 5 miles, I'm nearly 2 gallons of gas per week less than before... or about $7/week at current prices. That's worth it IMHO.
=Smidge=
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Yup (Score:5, Funny)
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Re: (Score:3, Insightful)
Remember that the more avenues you open up for the government to have information about you, the more you open up the possibility of them doing things with it that you will not be happy about. History has shown that once you put more power and information in the government's hands, the likelihood of removing it i
Re: (Score:3, Insightful)
Re: (Score:3, Interesting)
It uses the full tank as a baseline, not empty. (Score:5, Insightful)
Basically you fill the tank until the pump shuts it off, and reset the odo. This is your start point. You drive for a while, generally until you need gas again, and then you refill the gas tank until it again shuts off automatically, and note the amount of fuel added. You look at the odometer, and simply take the mileage there, and divide by the reading on the pump.
As long as you never fill your tank halfway, and you don't top off or otherwise force the gas pump to keep going after it shuts off automatically, and you reset the odo every time you fill up, you can get pretty good mileage estimates this way.
It's a different method than what I assume the car's computer is using (I'd think it's using some sort of reading from the engine's sensors) but it's not an inherently terrible methodology. If you use the same gas pump/nozzle to fill up each time, I'd imagine it could probably be quite accurate. At no time does it require you to run your car out of gas.
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Re:It uses the full tank as a baseline, not empty. (Score:4, Insightful)
Yes, but a few tenths of a gallon is a big difference in a small car, where you probably have a small tank.
In order to get any kind of accuracy this way, you must do multiple tests on the same pump, because they are very much NOT standardized from pump to pump let alone station to station, and average the results.
The pressure cutoff is adjusted directly on the nozzle. Most of the time there's an easily-visible screw and you can adjust it with a standard screwdriver. I've done it myself when the nozzle was clicking off too readily.
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Re: (Score:3, Insightful)
It's important to have accurate mileage ratings on cars, and it's hard to understand how the EPA could be so bad at it. Why do they try to estimate instead of just sampling?
Here's a simple approach: When a car comes in for an oil change, read the mileage rating stored inthe on-board computer and upload it to an EPA database. Problem solved.
I think the main reason for a test is so it can be applied to new or modified designs; it's hard to sample the fuel economy of a car that isn't in use yet. Addi
Re:Sampling? (Score:4, Informative)
The car manufacturers test their OWN cars, but not in real-world. They put them on a Dynamometer, drive it in varying conditions, and collect the carbon it produced. From that, they calculate how much fuel the car burned and then derive the MPG from that.
Of COURSE a hybrid would SHOW a huge MPG rating by that government standard. A total electric would show ~ (infinity) as it produces NO carbon itself.
Oh, and for anyone who thinks I'm just blowing smoke out of my ass (pun intended)
http://www.fueleconomy.gov/feg/how_tested.shtml [fueleconomy.gov]
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Re:Sampling? (Score:4, Insightful)
If so, here's your cluebat: Unless the electric component is bringing in power from outside the system, the test is completely valid, because all the power comes from the gasoline in the tank. Turning the engine into a generator which powers and electric drive-train doesn't change this simple fact.
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Re:You must be new here. (Score:5, Interesting)
I'm not sure this is completely true. For normal gas automobiles, I have encountered fuel economy very close to the EPA estimates, so I don't think there was any reason for the US automakers to "fight" the current standards; they seemed to be adequate. Now, the US manufacturers were "late" to market with Hybrid vehicles, and I can think that for the last several years, they would have been fighting hard to CHANGE the standard rather than keep them the same. Perhaps that's what you meant (IE, fighting the last few years and finally getting success) But as we all know from actual performance of Hybrid vehicles, there has been significant reason to change the ratings process. I can tell you from my experience buying cars (and looking at both Toyotas and Hondas) that, at least from the perspective of the dealerships I visited, they have been hoping and praying for change. They were very well aware that Hybrid cars were not achieving the stated EPA ratings. And they were also aware that even though the short term effect was a boost in sales, the long term effect was a dissatisfied customer. Any good dealership is highly interested in repeat customers, and they know they have to balance that with selling the car for the highest price they can. They don't want something like false fuel economy ratings to interfere with the customer relationship. I know that in the case of two dealerships that I visited, when I expressed some interest in a Hybrid vehicle, one of the first things that the sales people told me was that although the fuel economy was significantly better, in most cases it would not be nearly as good as the EPA rating indicated. In fact, one of the sales people told me that he would like to remove the EPA ratings from the car sticker, but that they weren't allowed to do so.
So actually, I think that ever since Hybrid vehicles hit the market, it has been in EVERYBODY'S best interest to adjust the rating standards, but the EPA has been slow to respond with improvements. But don't go blaming the EPA either. Keep in mind that they had to come up with one standard that applies to both conventional and Hybrid vehicles. The basics of that might be simple, but the effort to come up with something that all the manufacturers will agree with was probably a lot more involved.
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In other news... (Score:4, Funny)
But on the brighter side of things, the Hummer is now rated at 75mpg on the highway.
Re:In other news... (Score:4, Funny)
Yeah, I heard on the Discovery Channel that a bicycle gets infinite mpg, but now the EPA says it's only *countably* infinite mpg.
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Re: (Score:3, Funny)
(But then, that's probably only comparable to cars using up coolant and motor oil; the energy for the trip generally does not come in liquid form, and I don't know the volumentric measurements of bannanas and begals..)
Re:In other news... (Score:5, Funny)
Is that miles or meters per gallon?
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Re:In other news... (Score:5, Funny)
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How to drive a hybrid (Score:5, Informative)
Re:How to drive a hybrid (Score:5, Informative)
The highway estimate is a little more accurate. Cruising at 65-68 mph under optimal conditions (no AC, etc.) I usually get around 47 mph.
It's also kind of funny how much the weather affects my MPG. Cold weather drops me down at least 5 MPG. I'm not sure if that's particular to hybrids, or if that's every car.
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Not just for hybrids (Score:5, Informative)
Why so much Hummer Hatred? (Score:3, Insightful)
There are three factors which determine how ecconomical (and environmental) your transportation is:
1) What you drive
2) How much you drive
3) How you drive
Personally, I don't drive a Hummer nor do I drive a prius (I don't want to own either car because they do not suit my needs or wants) but I'm positive I have better "Fuel Ecconomy" than either car. My feet get me far greater mileage than any car and I use them far more than my car; I end up using transit a lot too.
I used t
Re:Why so much Hummer Hatred? (Score:5, Funny)
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Re:Why so much Hummer Hatred? (Score:5, Insightful)
It's too damn big. You youngsters probably don't remember this, but there was a time when you could actually see what's going on ahead of you in traffic.
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Re:Why so much Hummer Hatred? (Score:5, Insightful)
I doubt it has anything to do with Americans being the way they are. Hummer driving, like driving V12 Benzes and BWMs 200kph on the autobahn, is conspicuous consumption. This is a species-wide phenomenon which proves they have the resources to burn & some like Freud would say, proves their fitness for reproduction in attracting the female of the species.
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Re: (Score:3, Insightful)
At least the latter do so in style.
No... the invalid ratings are due to poor testing (Score:5, Interesting)
far as im concerned they should require someone to
Re:No... the invalid ratings are due to poor testi (Score:3, Insightful)
To test everything evenly you need a constant situation that will not change without you manually changing it, a "real city" is the complete opposite of this. So if Tuesday you get stuck behind a bus and on Wednesday you've got the rad to yourself, the results are clearly quite different.
not about payback time (Score:5, Insightful)
It's about how much more we could do by using technology in a sensible way rather than spending it on finding ways to allow every Joe to accelerate a 7 ton monster truck 0-60 in under 4 seconds!
Re:not about payback time (Score:5, Insightful)
When the green movement can give me technology that at least maintains my current lifestyle, while showing savings on the bottom line within a year or two, I'll go for it. Until then, well, it can keep selling to the true believers.
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Re:not about payback time (Score:4, Interesting)
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Re:not about payback time (Score:5, Insightful)
I really can't accept your picture of scarcity and want. I have enough faith in human ingenuity to believe that not only will my lifestyle continue, it will get better and better.
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Re: (Score:3, Insightful)
I mean, how much tax is there on a gallon of gas in, say, the UK? I lived in the UK for a couple of years in the 80's, have loads of relatives there, and visit regularly. I know for a fact that government policy is to keep gas prices as high as possible (just right below where the peasants start to rebel) in order to encourage people to use public transport.
In other news (Score:5, Funny)
Huh? (Score:5, Interesting)
So how are other cars faring with the new calculations? I'd imagine it should be proportional to the current numbers?
Realistically (Score:5, Interesting)
And with the tax credits (I think ending this year or ended) it's been typically cost effective depending on what type of hybrid you get. A civic hybrid from last year would have paid for itself within 8 months with my level of driving, a 3000 premium over regular civics with 2000-2500(I forget where it was last year) back from the gov't means a difference of 500-1000 to make up, which is pretty easy with how gas prices went last summer.
I hate these people who run the numbers and leave out other numbers. Tax Credits on IRS page [irs.gov]
Yeah, they aren't guaranteed, but if you buy early you can get them pretty easily. Or who say "Batteries are expensive" when they have very long warranties that cover it. If you want to pretend to know what you're talking about, then do the proper research. If you want the most cost effective vehicle, gas wise, get a bike. You have to be comfortable with your car, hybrid or not, and if you don't like them don't get them. But don't make up fake reasons.
Re:Realistically (Score:5, Insightful)
And I can't stand it when people talk as if getting tax credits reduces costs. It transfers costs to someone else. Ironically, even the guy who takes his bicycle or public transportation to work is going to have to shoulder some of the federal income tax burden that you - as a driver of your own personal vehicle - are able to shrug off because of the flavor of engine you bought. Unless you can demonstrate how your purchase of that vehicle is going to reduce the federal government's cost of doing business by the amount of your tax credit, you're just asking everyone else in the country to write you a rebate check out of their own income.
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There are alternatives to the EPA numbers (Score:4, Informative)
Hybrid Mileage Database [greenhybrid.com]
So far the EPA numbers in TFA seem to line up well for the Prius at least, but I haven't looked at any of the other numbers.
Diesel! (Score:5, Informative)
Add to this the facts that diesel fuel requires less energy to produce, and can be made (mostly) renewably from just about anything that grows, and diesels blow hybrids out of the water in terms of fuel efficiency.
Maybe this change in rating schemes will take some of the marketability out of hybrids and raise awareness for diesel... though more likely it will just encourage people to say fuck it and buy an RV to drive their kids to soccer practice.
Re:Diesel! (Score:4, Insightful)
The reason that diesels haven't kicked in is because they don't pass the emissions standards in any state that follow "California Emissions." Has nothing to do with the EPA at all. The fact that this includes California, NY, and all of New England reduces the number of potential buys so much that it's simply not worth pushing to market in the US.
Hopefully within a few years the auto manufacturers will produce vehicles that do pass and they'll become available. Juat about every automaker has new engines coming to market that do meet the requirements, so things should change soon
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How does this make the cars less cost effective? (Score:4, Insightful)
No, plugging these new numbers in makes the cars *appear* much less cost effective. The fact of the matter is that plenty of hybrid owners were actually reaching their posted fuel efficiency ratings, unlike gas-only cars which do not. And whether the car is stopped in traffic or not, a non-hybrid car is still consuming fuel while a hybrid is not. In fact, hybrids do much better in heavy traffic because under a certain speed (35 Km/h for the Prius for instance) it's just running on batteries.
I think the EPA just changed the way these cars are rated because other carmakers complained that the numbers were "unfair".
Online consumer MPG submited database (Score:5, Informative)
-Rick
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Accurate for my single data point, anyway (Score:3, Informative)
It's about damn time the EPA revised their ridiculously inaccurate tests. The data has been off for years, for all cars.
Re:Strange but true (Score:5, Insightful)
The answer lies in more than just its batteries. There are plenty of auto manufacturers jumping on the bandwagon by battery-backing their existing engine designs. That won't do much. Toyota took a different approach. For one, the engine of the Prius was replaced with a more efficient Atkinson Cycle [wikipedia.org] engine. This engine would normally not be viable in a car, as its peak output is quite poor. However, the Prius uses stored battery power to provide maximum torque when accelerating. This makes up for the engine's poor peak power output. Furthermore, the torque delivered by electrical power is more fuel efficient than driving an Otto-cycle engine to sudden, peak power-output conditions.
But the engineers didn't stop there. They used the research behind Continuously Variable Transmissions (CVT) [wikipedia.org] to develop a transmission that can evenly split the power between the electrical and gasoline powered components of the car. This transmission can smoothly transfer power between different sources and outputs, avoiding the limitations and excess power consumption of the traditional geared transmission. This transmission (which Toyota calls a "Power Split Transmission") is only workable in a small car like the Prius, due to the torque limitations of most CVT designs.
Finally, Toyota further hedged the car's bets with computer control and tuning over the entire power system, a low air-resistance body design, lightweight aluminum construction, and vacuum flask coolant storage for fast warm-up times.
What you're looking at is the modern equivalent of a Chevy Sprint [wikipedia.org]. Those three bangers got great mileage at the expense of power and comfort. (My mother had one and managed to get 58 MPG on the highway!) The Prius uses modern technology to provide similar returns, but without the drawbacks that made the Sprint so unpopular in the first place.
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Re: (Score:3, Insightful)
Re:My 2002 Saturn 2SL still averages 30 and 40 mpg (Score:5, Funny)
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Re: Hybrids (Score:5, Insightful)
True. Buy you also see significant gains in mileage vs. gas-only vehicles when not driving conservatively all the time.
False. The batteries in a Prius are no more toxic than any other battery. Also, they can be **completely** recycled at end of life.
Can you prove this steep drop off in value at year 6? If not, than why state it? Let's assume for a moment that this year 6 valuation drop-off occurs. How much is that going to matter to someone who has held the car for 6 years? Probably little at that point.
Now you're simply sputtering off nonsense. Don't spout bullshit unless you know someone isn't going to catch you:
http://www.toyota.com/about/environment/technology /2004/hybrid.html [toyota.com]
Toyota has a comprehensive battery recycling program in place and has been recycling nickel-metal hydride batteries since the RAV4 Electric Vehicle was introduced in 1998. Every part of the battery, from the precious metals to the plastic, plates, steel case and the wiring, is recycled. To ensure that batteries come back to Toyota, each battery has a phone number on it to call for recycling information and dealers are paid a $200 "bounty" for each battery.
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Re: Hybrids (Score:4, Informative)
Utter horsehit. I drove a Prius from MA to TX, it was almost all freeway driving at 55-70 mph. Not only that, there were two of us in the car, and the back was entirely filled with cargo, seats folded flat. (We were moving.)
We averaged 47mpg.
Take your Detroit astroturf FUD elsewhere.
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