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Hybrid Cars Don't Live Up to Mileage Claims
Omega1045 writes "Wired News is running a great little article about how hybrid cars (specifically Honda and Toyota models) do not come anywhere close to living up to their fuel efficiency claims. The article highlights that the EPA tests are more to blame than the car manufactures. Consumer reports has shown that the mileage for these cars can be as low as 60% of the claims. The article also links to a blog authored by hybrid enthusiast Pete Blackshaw detailing his failures getting any real answers on why his Honda Civic Hybrid isn't getting better fuel mileage. It looks like these cars are more hype than help in the battle against pollution and foreign fuel reliance."
You can't create more energy from less fuel. You can do it more efficiently, but this going to the electric motor and back isn't that efficient.
Gets 45-55 MPG. If you drive them like a race car of course the MPG is going to be a lot less
An interesting alternative fuel is biodiesel:
- We can make it in the US
- Runs in existing diesel engines
- Almost all emissions reduced vs. dinodiesel
(for NOx there are some interesting additives
being produced).
- Much less toxic/dangerous than dinodiesel/gasoline
- Exhaust smells like french fries!
I can speak to the accuracy of hybrid fuel economy numbers, but I did do a bit of research and ended up buying a small gas-only car instead. I found the fuel economy of the hybrids wasn't so much better that it warranted the significant price increase.
I wrote more about the issue on my weblog: Why I didn't buy a hybrid car.
I never got below 50MPG, ever, and that was living in the thin air of Flagstaff, AZ, at over a mile in elevation. I got closer to 60MPG in the lower and warmer Phoenix, AZ.
31.5 isn't better than what one of the guys at work gets in his escort. And if they aren't more efficient then they are wasted.
Food not Bombs is a nice platitude but it breaks down when you notice that the Bombees are usually well fed
The Honda Civic Hybrid is an example of a hybrid is set up with the following:
Energy is lost in the conversion from gas to electricity, it's also lost in the storage in the batteries and the usage from the batteries to the wheels. You konw and I know that while normally this would all be lost in the braking, now it is stored and used to assist with acceleration.
The odd part is that while driving where you aren't using the brakes a lot, the transmission, weight improvements and aerodynamics will be the only improvements in your efficiency. The electrical assist means that your engine can be improbably weak, but I don't know if that necessarily translates to a more efficient engine.
Here's something which nicely describes why I'm skeptical about the true performance of hybrids:
1992 Civic line:_ Civic.shtml
http://www.fueleconomy.gov/feg/bymodel/1992_Honda
2004 Civic line (including hybrids)_ Civic.shtml
http://www.fueleconomy.gov/feg/bymodel/2004_Honda
I'm not sure why, but it looks like my 1992 1.5L Civic Hatchback is(was) more fuel efficient (city and highway) than the modern 2004 Civic Hybrid. I don't think U.S. government numbers are right, but they're close enough to try to make some kind of a point :-)
As an aside, I was looking into the hybrid transmissions and from what I could tell... I was wrong, the Honda Insight was manual-only, but the newer hybrids sometimes sell with the choice of an automatic or continuously variable transmission... oddly, the fancy transmission hurts highway fuel efficiency, but it helps in the city.
Note that comparing an aluminum hybrid to a galvanized steel compact, e.g. the Insight to a "regular" car, would not be an apples-to-apples comparison since if you were to remove all the weight from the electrical system (adding hydraulic brakes) and increase the engine size to match the lost horsepower, the new gas car would be more efficient than other gas cars on the road today, and might even be better on the highway than the hybrid. (Although it really should fail to beat the hybrid in the city)
A 2004 Honda Civic Hybrid to a 2004 Honda Civic would be a more reasonable comparison than my 1992 to a 2004... the 2004's have bigger engines and are less fuel efficient. I'd also expect the 2004 hybrid to have more horsepower than my 1992 car... so I'll admit, it's not a fair comparison...
But there may be less expensive, more fuel efficient non-hybrid vehicles on the market.
(In reality, I get about 37MPG on the highway, ~30 in the city... the car _is_ 13 years old)
What needs to be understood is that hybrid cars offer better gas milage only depending on certain conditions. If you are driving without much acceleration/decceleration, then you basically do not get the advantage of hybrid technology. For city drivers, you get the recharge while braking and it makes for very efficient energy consumption. Just my 3 cents.
While the references indicate that the actual mileage is lower than what is claimed, the vehicles do get better gas mileage than standard automobiles. From a conservation standpoint, that's still a good thing. From a Truth In Advertising (ha!) standpoint, it certainly stinks.
Not really, a normal civic get about 30-35 mpg anyway. The hybrid doesn't seem to be buying more than 1-2 MPG. Hardly signifigant.
Give me Tango or Tzero over any hydrogen creation anytime. Simpler, saner, better performer.
Check out Michelins Challenge Bibendum results, EVs routinely kick those hybrids asses in every relevant category.
http://validator.w3.org/check?uri=http%3A%2F%2Fwww.slashdot.org Errors found while checking this document as HTML5!
From a Truth In Advertising (ha!) standpoint, it certainly stinks.
Yes, it does, but don't make the mistake of blaming the companies or the advertisers for this. Federal regulations prohibit using any number other than the one calculated by the EPA test in advertising a car's mileage. This test was devised almost 20 years ago, and doesn't actually measure fuel consumption. It measures the emissions, and uses that data to calculate efficiency, and thus, mileage. Obviously a hybrid (with very low emissions) is going to skew the test.
Where's my lobbyist? Right here.
One nuance that the Wired article didn't cover is that mileage depends greatly on driving style. If I make short, aggressive hops across town my Prius' mileage drops to the mid 30s in summer or low 30s in winter. If I drive more sedately (at the speed limit, with gentle acceleration instead of punching the throttle at the lights) I get mileage in the mid to high 40s. Not bad for a comfortable four-door family car.
I can drive all day at 80 mph and get 41 MPG. I do it several times a year to visit family and/or just road-trip around the state.
The lesson to take is that good mileage requires both good tech and good habits.
yes it has been adressed, new hybrids have lifetime or 125,000 mile pack warrenties.
Bio is also over 3$ a gallon. Thats over 43$ a tank of gas!
31.5 isn't better than what one of the guys at work gets in his escort.
For what it's worth, I have two Saturn SL cars, and they both average between 42 and 44 miles per gallon. One is a 1997 model, the other 2002. Aside from three or four times when someone else filled up the tank and forgot, I can account for every single gallon of fuel and every mile over the last seven (and two) years. Oh, and I bought both of them brand new from the dealer for $12K and $10K.
These cars are not hot rods, but they have plenty of power to climb hills at 65mph and I am almost always a bit quicker than the other cars.
So using my own experience as a benchmark, I can see that these 50mph+ cars may have a claim for better efficiency, but they are also a lot more expensive than mine.
A dingo ate my sig...
I've got two 2003 Toyota Prius' (me and my wife). The EPA says 52mpg/city and 45mpg/highway. My car gets between 45 and 50, my wifes gets between 50 and 55. We both fill up about 10 gallons after going about 500 miles. Not too shabby.
From what I've read, fuel efficiency does depend on temperature (mpgs drop some during the winter) and how the person drives. I've paid attention to my car and have increased fuel efficiency by a couple of mpgs.
Several people I work with have hybrid Civics and Prius' and they all function as advertised. Not sure what the deal is with other people seeing crappy performance.
As a happy Honda Insight CVT owner (which is rated at 57MPG highway), the lifetime average on my 2001 model is 56.1 MPG. I bought it used, and the previous owner had averaged 54.1 MPG. My personal average is 62.1 MPG. The manual transmission Insight can do even better.
So while there are some hybrids that fail to live up to the mileage claims, with careful driving your average Honda Insight can beat the EPA estimate by an appreciable margin. But a key is careful driving. If you're a foot-to-the-floor driver, or frequently drive on roads well in excess of the EPA "highway" speed (50-60MPH), your mileage will definitely take a dive.
You're not going to get anywhere near the rated mileage doing 85 on the freeway, or if your commute is all stop-and-go.
Matthew P. Barnson
I learn what I think when I read what I write
I can't speak for the Honda, as I have the Toyota Prius, but I get consistently 48-9 city MPG, (the '02 P is rated at 47 city).
If you don't know how to drive a hybrid, then you will get poor MPG. Period. Here's how to get high MPG in a hybrid:
It is absolutely understandable why people try to drive the way they are taught: smooth acceleration, hit the brakes often, etc., but that is the antithesis of getting good gas mileage in a hybrid.
Finally, the main goal of the hybrid is reduced emissions; increased MPG is a byproduct.
Yeah, right.
When you drive a hybrid, you will get better mileage if you change your habits to make more effective use of the hybrid's abilities. This doesn't mean you have to poke along... I accelerate hard so that I am using my batteries and minimizing the time I spend burning a lot of fuel in the gasoline engine. Plus, it's fun. You'll also get better mileage if you pay attention to things like tire pressure. Dealers like to inflate my Insight tires to 32 psi all around, even though 38 psi is what Honda recommends. An Insight with 32 psi tires looks like it's running on flats. I inflate to 44 psi. The mileage change is dramatic.
As for the original article, it has some good points in it about the EPA tests. It also has some real head-scratchers, like this: "Schmidt says hybrid cars use computers to more precisely control the flow of gasoline and have more efficient catalytic converters..." and this "hybrid cars' ability to limit emissions contributes to the disparity in EPA versus real-world numbers." There are many, many cars that have the same or better EPA emissions rating (10/10) as the Civic Hybrid and the Toyota Prius. All cars today use computers to regulate gasoline flow.
When you get your hybrid, turn on its instantaneous readout of mpg and use it to give you feedback on your driving. It will train you. Happy driving...
Can't you see that everyone is buying station wagons?
Absolutely correct.
And the other truth is that if they will give a good return only if driven in an environment where there is a lot of breaking from reasonable speed to 0 and starting after that all the way to reasonable speed.
They do not give good return in a traffic jam environment because the crawling gets the batteries drained to the point where the ECU decides to recharge them and starts from cold (and there is not enough energy recovered from breaking). This means engine running in the most inefficient mode combined with lack of working catalyst conversion (cats need to warm up too. It works just about enough to warm up and then shutdowns again for a period long enough to go cold.
So basically they will live to the expectations only in an environment where there are no highways and no long stretches of open road. At the same time it should not be congested and there should be no traffic jams as such. Frankly, I cannot think of any big city in the world that fits this description. There are possibly one or two medium size towns here and there, but even there you are likely to get better economy out of a high class recent petrol engine like on the Sirion SL or the Honda Jazz (not to mention diesels, CNG or LPG).
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Bought my 2004 Honda Civic Hybrid in October. I've got a little over 7,000 miles mostly city driving. My daily commute round trip is about 16 miles a day. I've also made several trips to Orlando which is about 200 miles round trip. First month I averaged around 38 MPG.
Modified my driving style and second month average MPG was around 41.
Modified my driving style and third month average MPG was around 43.
After a couple of months of practice (also started driving mostly with the AC off, and I live in Florida) my MPG is now averaging between 45 and 48 MPG.
My wifes car started having problems, so she drove my car for a week, average fuel milage fell to 37 MPG.
The reason I love my car so much is because it is a real "drivers" car. What I mean by thats is the car will do everything that it claims to do, if you are a skilled enough driver.
The camaro I traded in for the Civic Hybrid claimed to do 150 MPH, but almost everywhere I go has a Max Speed limit of 45 so I was never able to see if I could drive the car at that speed. Now I have a car that gives me a driving skill test that I can actually do.
the vehicles do get better gas mileage than standard automobiles.
Perhaps... it's kinda hard to do the apples and oranges comparisons for fuel efficiency but:
- 89 Honda CRX HF (high fuel efficiency model) got me 35-40 MPG with a very marginal engine.
- 89 Pontiac Lemans - 33-37 MPG with an engine in fair to poor condition.
- 92 Honda Del Sol gets 30-35.
None of the quite matches the Insight or the prius, they rank right around the Civic Hybrid in spite of me being a bit lead-footed and the cars all being worn out.
The problem with car diesel engines (speaking as a brit who's driven a few) is that yes they have good mpg but they also generally have lousy performance compared to a petrol engine of the same capacity. Also diesel exhuast despite filters and catalyst its still pretty noxious and even new diesel cars can be seen disappearing off in a cloud of black smoke if revved hard. Plus they sound awful on idle. Obviously these points don't bother many people in europe since diesel cars are big here but they're not the perfect transport solution.
So why as a society (I'm referring to the US here, the EU is very much ahead of us with biodiesel) don't we promote this more often? Let's reduce our foreign oil dependence, and not have a need to drill ANWR. Use Diesel & Biodiesel!
In what volume can BioDiesel be produced, and what is the cost in doing so? We use a significant amount of oil. My understanding of BioDiesel did not lead me to believe that it could produced in the same quantities that we currently consume oil, and at reasonably comparable prices.
I'm an Audi driver myself, and I love the VW/Audi lineup. They sell a TDI (Turbo Direct Injection, for those not up to speed) equipped A4 in Eurupe, but not in the US.
There are 2 reasons why diesel isn't popular. 1 is because of it's stodgy, noisy, smelly, and shaky public image. That's not true anymore, but the image lingers. The other reason is because of CARB. California Air Research Board. You CANNOT buy a new passenger diesel car in 2004 in states which follow CARB regulations (instead of EPA regs) Those states are CA, NY, VT, MA, and ME. A very large percentage indeed.
"No fair, you changed the outcome by measuring it!" - Professor Hubert J. Farnsworth
I have a couple friends who get 55-60 MPG out of their Prius'. But if you drive well over the speed limit, the efficiency drops dramatically.
Insanity is a gradual process; don't rush it.
Err if they burned through x gallons of fuel to go y miles, doesn't that mean that x gallons of damage was done to the environment via CO2 emitting, resource depleting transportation over the y miles between point A and B.
The fact that some of the chemical energy in the gas got turned into electrical energy before its kinetic use doesn't make a flying bit of difference to the environment.. does it?
There is a lot of opposition from all the trucking unions and lobbying from the transport companies over cleaner diesel, since it costs a little more then dirty diesel it would cut into there bottom line. Not sure if we will ever see it.
As for buying a TDI, I would recommend it, I would also recommend you purchase a VAG-COM if you already don't have one. Takes the guess work out of working on your VW.
I bought a used 2000 Insight (5 spd) and I've had it for about 7 months now.
In my experience, I've consistently gotten around 60 miles to the gallon . In the winter it dropped to ~59 (Missouri weather), but on my current tank of gas I have gotten 64.8 MPG over the last 240+ miles. I drive about 5 miles to work one way in city roads, with an max speed of around 40 mph and several stop lights. On weekends I drive it on the highways and my mpg figure usually rises even on a 5-10 mile trip on the highway, which I figure means that I've gotten significantly better mileage. My worst mileage was when i drove to Indiana last thanksgiving and I did 80 mph most of the way. I got 55 MPG then.
In my opinion, the hybrids need to be driven a certain way. You can't really drive them the way you drive a regular car (accelerate too fast / brake fast). Dont get me wrong, I still accelerate normally, but being able to anticipate stops better and using the regenerative braking and getting the engine into auto-stop faster when the batteries are charged works like a charm for me. Insight Central has some driving tips that helped me a lot.
I'd chalk this guys problems up to him not adjusting his driving style to fit the car. Thats my 2cents.
While your post IS funny, it's also, uh, wrong.
Hybrids have cleaner emissions compared to standard vechicles, regardless of mileage.
This is how they qualify as a LEV and SULEV (low-emission vehicle/super-low-emission-vehicle).
So, when compared to the more "average" pollutant level of the Escort's emissions (I don't believe there are any LEV or SULEV escorts available, correct me if I'm wrong), 31 hybrid's MPG in a hybrid can be considered "way better for the environment" than the Escort's 31 MPG.
... Hate the Game.
So what can we take from this? EPA's mileage estimates are extremely flawed and based on 1970's technology. Duh.
But the real problem is that the article is completely ignores the driving habits of the person singled out in the article!!!
Are his tires properly inflated? If not, subtract about 10% from your estimated mileage.
Is he making short trips? If so, subtract about 30% from your estimated mileage. (This is because a hybrid's primary function is not to get the best gas mileage it can -- instead it's goal is to reduce emissions to the maximum extent it can. In order to reduce emissions, the catalytic converter must be hot -- and to get it hot, the engine has to run. So if your trip is less than 10 minutes, you are shutting off the car right when it has warmed up to reach its peak efficiency.)
Is it cold out? For the same reasons explained above, weather has a huge effect on efficiency (never mind the fact that battery efficiency also decreases with lower temperatures.)
To put this all in prespective - I've had my Prius for a couple of years now and have kept ridiculously detailed track of my mileage figures -- and they are all over the map depending how I drive.
When I went with the tires that came with the car, on hot days, with no air conditioning, and drove in a method to maximize efficiency, I could get 60+ miles per gallon. Turn on the air conditioner and drop that to 40.
During the winter, the best I can usually do is 45.
And when I recently switched the tires (for better handling and tread life), my mileage droped by about 10%.
Drive over 70 MPH, drop it to 40. Drive over 80? Drop it to about 35? (I've never gotten less than 38 for a whole tank average - and that was only when I abused the car.)
All I am saying is that mileage is highly subjective. This is true for all cars -- but with the hybrids, they keep such careful track of the mileage that it is always on people's minds.
Actually, I just watched a show which had one an engineer talking about hybrids. They claim that stop-and-go is one of the ideal operating conditions for hybrids. The reason is that it's running off of batteries and not using gas. Then, once you get out of the stop-n-go, the batteries get recharged. That sure seems to make sense to me. Best of all, he argued that long distance highway driving, typical in America, would provide for some of the worst mileage you can get from a Hybrid as it will mostly be running off of it's ICE. Worse, most Americas tend to drive faster than cruise speeds, further increasing the load on the ICE. Again, that seems to make sense to me.
Because diesel engines didn't run as clean as they do today. They had the good gas mileage but they were big polluters and pretty loud so they weren't very popular. Now that they run way clean, quieter, and the gas prices are so high, people might start turning to diesel. I think something like 40% of all the cars in europe are diesel when it's only like 1% in the US. Oh and it doesn't help that you can't get diesel fuel in every gas station, maybe when it becomes more of a standard and you just see diesel cars in show rooms, more people will start buying them.
I love my '96 Passatt TDI. No matter how or where I drive, with or without AC, I get 35 mpg. It never wavers at all. And it's got surprising pickup for something officially rated at 90 hp. Of course, the backside of that pickup is that you need to shift before the end of the intersection. :-)
It's exempt from emissions testing too, which is a big plus.
My next car will probably be a Beetle TDI as soon as they have factory installed XM radios.
Honda Insight
2003 Honda Civic Hybrid
Low sulfur diesel fuel will be required in the year 2006 in the US, so the mandate has already occurred. There is a lot of debate about whether older diesel-fuel cars will work well with the newer fuel, though.
Never look down your nose at others. Someday, someone is bound to see your boogers.
On combustion engines that use the standard rings to seal pistons, you're not going to see your optimum mileage for several thousand miles. Depends on tolerances and manufacturer of course, but I've had several cars that their mileage/power output increased steadily up till about 8000 miles.
Also, as everyone's already pointed out, how you drive plays a big role, as well as tire pressure, and where you're driving.
I'm trying to sell my neon currently. Great car but I've moved on. It's a 2.0 litre gas engine (manual transmission), and I've gotten 45 mpg on roadtrips with it. It dynos at about 140 hp. It's not all about the power, it's about how efficiently you make the power and definitely how you use it. People should have to take a class when they buy a hybrid as it's my experience that most people don't know how to drive a NORMAL car properly.
Batteries are also the single most agressively recycled automobile part, with deposits charged and refunded like they are on pop bottles in some states.
www.wavefront-av.com
You can't directly compare diesel and gasoline mileages. A gallon of diesel contains 13% more energy than a gallon of gasoline. Therefore you mileage is equivalent to 35-44 gasoline miles per gallon. Don't gloat too much.
You really, really ought to measure fuel efficiency in miles per kilogram of CO2 emitted. Miles per gallon is very misleading because fuels can have widely varying energy contents.
My best mileage on a tank of fuel with my Golf TDI is 49.1 miles per gallon. That's for an entire tank. Nearly 700 miles.
I rarely get fewer than 43 miles per gallon. I can easily go 500 miles before thinking about filling up.
That and diesel is $0.25 less than gasoline right now, which makes me happy. On top of that, I have the option of using biodiesel, which is a domestic fuel. Admittedly, I've never used biodiesel, because you can only find it at farmer Co-ops out in the country.
I've been a skeptic of hybrids for a long time, and this only serves to reinforce my skepticism.
Diesel is a good near term solution for fuel efficiency. Volkswagen has been doing a great job of it, and I hope the availability of diesel engines will increase in the future in the US.
My Karma was at 49, then they switched to words. All that work for nothing!
Christ, the claims for the mileage on my 2001 XTerra were off, too. What's the BFD? This kind of crap reeks of gas company crybaby marketing. Who did this study? Texaco?
That said, I'd still love to have a hybrid...and right now the 2005 Ford Escape Hybrid is looking like a winner, unless Nissan can get off it's collective ass and get me a 2006 XTerra Hybrid.
blog |
and live in Scotts Valley (Santa Cruz mountians just north of Santa Cruz). The driving is mixed (50% city, 50% highway). I, like many others (there are sites out there where people graph their milage) get about 46-47 mpg on average. The high epa rating was ~50 mpg, which puts me at 97%, and I don't drive like an old lady either.
My guess would be that either something is wrong with this guy's car, or (more likely), he drives way too fast. You aren't going to get anything near epa rating if you're driving 80mph, regardless of the car.
On driving too fast, it might be that he doesn't realize how fast he's going (I always had Fords, which are *loud* and when I got my Prius I was always speeding because the car is so quiet and smooth)
Why so much FUD about hybrids lately? I've noticed a knee-jerk recation from so many people when I tell them I own a hybrid ("oh, you have to plug it in" or "I heard they are really slow" -- all bull by the way). The Prius is just a very well engineered car and I've very happy with it.
\forall code \in C, \frac{\Delta readability(code)}{\Delta t} < 0
Stop spreading FUD.
We're not using lead batteries, damnit! It's 120 1.2 v NiMH batteries. The battery pack weighs 63 pounds, not 200 as you assert, and the entire Honda Civic Hybrid manual car weighs only 129 pounds more than a comparable Honda Civic EX manual model.
There's no lead, no mercury, no cadmium in these batteries, and they're recyclable. Just like all the other NiMH batteries.
--You will rephrase your request for me to go to hell. Goto statements are not acceptable programming constructs
and is still lower than my Volkswagen TDI at 50mpg
:-)
on average I get from 47-53 MPG burning that earth destroying Desiel fuel
I also paid much less than the hybrids, have a much lower TCO than the hybrid cars and can get it serviced anywhere while your hybrid can only be serviced at "authorized" service centers.... AKA nobody will touch it but the dealers.
yes I would have a lower TCO if I bought a saturn and settled for lower MPG in the 40 range (overall costs would have been cheaper too.) but I couldn't turn down the insane deal I got on it. (5000miles on it and $12,995 out the door)
hybrida are neat, but not worth owning outside the "neat" factor as thereare no advantages and lots of disadvantages.
Do not look at laser with remaining good eye.
The Ford Focus PZEV has practically zero emmissions and will be widely available later this year. The gas mileage shouldn't be too much different from your regular Foci - or the above mentioned hybrids apparently...
The Toyota Prius uses an ICE system. It involves two electric motors, can operate "silently" (purely off the electric motor) at low speed, and can only be used in conjunction with an automatic transmission.
The Honda hybrids use a system called "IMA", that functions more like an electric turbocharger. If a Honda hybrid is moving, the gasoline engine is running. Well, OK, there is an exception to this if you're coasting to a stop at speeds below about 10 MPH (3 MPH in the CVT), with the brake pedal depressed, the engine goes into "auto idle stop" mode. The Honda design can be used with a manual transmission (leading to the extraordinary mileage of certain models) and is less complicated than the Toyota system, but otherwise seems to be a wash as far as advantages when comparing the two.
I have to admit some bias here: I think the Honda Insight is in a class by itself. It was a brand-new model introduced in Japan in 1999, engineered from the ground up to be the MPG king of the mass-produced world. It sacrifices a lot to be that: no rear seat, "unusual" design (my brother-in-law says "ugly", but I think it gives the car "character"), all-aluminum construction (painful, painful body repair bills), high insurance costs (on par with high-end rear-wheel-drive sports cars), a fairly stiff econo-box-like ride due to really hard little wheels, a crappy stereo (until 2004, when they put a much nicer model in), and hardly any selection of "options": if you have an Insight of a particular year, other than air conditioning and transmission type, your choices are extremely limited.
But I still love the car :) Now, back to responding to your post!
The engineer that talked about the Prius "running off batteries and not using gas" must have been off his rocker, if what you describe is correct. The energy has to come from somewhere, and in the case of these hybrids, that's from the gas tank. The gasoline motor must run to recharge those battery cells. And the chemical energy (gas tank) to kinetic energy (motor) to chemical energy (battery) transition wastes a good deal of that energy. Add to that kinetic energy to potential energy losses due to regenerative braking, actual brake pads being used in hard stops, and it's a recipe for poor efficiency.
The numbers back this up: in city driving, a hybrid frequently turns in extremely disappointing MPG numbers due to these inefficiencies. The Prius takes a hit in its highway MPG numbers, because it has to leech power off the gas engine to recharge the battery it depleted in city driving. The Honda cars take the hit from the gas motor occasionally idling (rather than going into auto-idle-stop), and acceleration from a stop draining nearly as much gas as a "normal" car.
That said, a hybrid will beat the pants off any similarly-driven traditional gasoline-powered vehicle for efficiency in those conditions. But when the EPA rates city mileage higher than highway mileage, it's not taking into account losses in the battery pack: the car ends the test with a battery pack lower than it started.
Sadly, you can't beat the laws of thermodynamics:
- You can't create or destroy energy
- You can't hope to ever do better than break even
- You can only break even at absolute zero
Sounds like my life sometimes...Matthew P. Barnson
I learn what I think when I read what I write
CO2 isn't the only pollutant put out by internal combustion engines. In the linked comparison of NOx emissions, the vast difference in Prius vs. Insight emissions is not due to differing gas mileage, but other variables, such as different pollution control systems, combustion efficiency, etc.
I'm a nature photographer.
come on now, didn't you do any research into todays hybrid vehicles?
1) They use NiMH batteries and not lead-acid. If NiMH electrolytes are getting smeared all over the passengers, they probably didn't survive the crash anyways.
2) Again, NiMH and not lead acid or NiCAD so there isn't that massive environmental impact of the previous battery technologies. But I do agree we still need mandated recycling of some of these materials so they don't end up in lakes/etc.
3) The Toyota battery does not have to be completely replaced if a battery cell fails. Just the bad cell so there should be no large expense to replace the whole battery. Except maybe in a collision and again, that's going to likely be a total anyways....
4) our Dodge Dart is not getting very environmentally efficient milage( ie green house gases/etc ). There's more to good MPG with hybrid systems.
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
As many other hybrid owners have pointed out, driving a hybrid is different from driving a normal car. The way the various components of the drive train interact requires a change in driving habits. An earlier poster mentioned flooring it when the taking off from a light; I completely agree. I practice "goose, ghost, and feather-foot". Which means "get up to your desired cruising speed (plus a bit more) as quickly as possible, then back off for a moment and let the system shift into maximum cruise mode, and then make the smallest speed changes possible". It's true that driving at 85 does not help the mileage, but I do it anyway and I can live with the hit.
On the flats, playing maximum games, I can still average 54+ MPG. We now live in an area with more hills and I have noticed that the ups-and-downs really cause a hit on the mileage. Instead of the 48-52 overall that we used to get, we now get about 46-48 overall. I have no idea where these 31 MPG numbers are coming from, but our Prius was advertised as "52 city, 45 highway" and it has been doing exactly that for over 3 years.
Finally, we bought this car partly because we believe in the idea. Early Linux was not completely user-friendly, but you used it any way because you knew there had to be an alternative to the Dark Side. If you have the time/money to vote for new directions in the world, then you need to do it. Not everyone should drive a hybrid today, but the only way to move away from the world of the Ford Inexcusable is for some of us to be Early Adopters. We are and we're having a ball!
Peter & Maria
Ideally the combustion of a hydrocarbon breaks down into H2O and CO2. Therefore, in a perfect world, burning a gallon of gas in a hybrid engine, a SUV, or an unlucky lab rat should release the same products. However, it is also possible to get unwanted products from incomplete combustion and/or side reactions with the products. That is how you produce carbon monoxide (CO) from a combustion engine (as well as some other nasty gases). The reason that hybrid vechicles are typically thought to release less of these unwanted byproducts (and thereby qualify as ULEV, etc) is that the engines only run at their most efficient RPM value. A standard car engine runs the gambits of the RPM band as you drive, but a hybrid simply runs at the most efficient fuel/energy ratio to charge the batteries. If you're only dealing with one set of internal conditions, it is much easier to design an effective catalytic converter to remove the unwanted gases from the exhaust.
A better hybrid could be produced that utilizes an electric motor for the propulsion, and a fixed rpm diesel to produce electricity, regeneration from coasting and braking, and an additional sterling engine to capture heat from the coolant and the exhaust manifold.
The easiest way to gain fuel economy, however, is to drive a car that weighs 1500 lbs instead of 3000 lbs.
"Only in their dreams can men truly be free 'twas always thus, and always thus will be."
--Tom Schulman
Naturally, the technology, not the drivers, that is responsible for the poor fuel economy.
Nonsense. When I drive my 2003 Honda Civic Hybrid (yes, I actually own one, potentially unlike many other people posting here) on the highway, I am careful on the gas (I take a speed hit going up hills, I utilize descents, et cetera). On the Pittsburgh, PA - Washington, DC drive, I consistently average 51 MPG for the length of I76, I70, and I270. On the George Washington Memorial Highway along the Potomac, I can keep it above 53 going in and out of the city. For local traffic, I accelerate slowly and brake slowly (when possible) and that helps keep it above 48 MPG.
On the otherhand, when I feel like having some fun, the gas miliage can drop down into the low 40s (42-46 MPG). For my Civic, that is terrible, but still better than 90% of the cars on the road. I consistently score 575+ miles out of my 12.7 gallon tank.
A terrible driver could take an NSX and lose every race. An excellent driver can take a Kia and kick some serious ass. Likewise with fuel economy, a bad driver can make the most efficient vehicle guzzle gas while a good driver could get some decent range out of an SUV. The point is, a car's technology is only as good as the driver.
I think a lot of people out there get a gasoline-electric hybrid vehicle and assume that they don't have to think. That's not the case. There's a very good reason why the Prius and the Civic Hybrid show you whether the motor is assisting or charging and show you your instantaneous fuel economy. These tools help the driver alter their habits to get the best performance. If people are dumb enough to spend the money on one of these vehicles and then not use the technology correctly (understand how to drive with maximum efficienty and change their habits), it's not the fault of the engineering, it's the fault of the consumer.
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Except they aren't using lead acid batteries. They're using Nickel Metal Hydride batteries. I know that NiMH batteries aren't as bad on the enviorment as NiCad batteries but that doesn't mean that they're being recyled completely.
Did anyone else hear the NPR story this last weekend about owners that want their Prius to have the electric-only option in their car. Apparently this is the case in Japan. You can push a button and go electric only, and recharge the batteries with a plug or switch to the hybrid engine by the push of button.
My city mileage is less than what is advertised, and I'm doing my very best with slow accelerations and maintaining constant speed where I can.
But overall, I'm pretty happy with getting my 50 MPG.
Don't use air conditioning, ever. (2 to 4 mpg)
Drive at a steady speed, about 40 mph, in top gear.
Choose a route that doesn't involve hills.
Don't use oxygenated gasoline. (as if you have a choice!) (15% efficiency loss)
Don't drive through snow. (It takes energy to push the snow aside.)
Don't drive in very cold weather. (Cold makes rubber stiff, so tires absorb more power.)
If you can, adjust the spark timing for maximum efficiency. This setting may disagree with manufacturer's recommendations.
Contribute to civilization: ari.aynrand.org/donate
Look at the authors previous articles and you'll see he just wrote an article promoting fuel cells and hydrogen powered vehicles....
He looks/sounds more like a shock-jock than anything else. We're averaging about measured 45 MPG over 40,000 miles with a 2001 Toyota Prius(purchased in 2000).
IMO, the story headline should be more like this: "Car owners with poor driving habits get upset when shown actual MPG", or even "EPA rating is NOT REAL, it's a baseline for comparison dummy".
LoB
"Anyone who stands out in the middle of a road looks like roadkill to me." --Linus
Half of the mileage is based on driving style. I have a '99 Civic LX (Stock, no special airfilters/turbo-chargers/19" rims/lame rear spoilers) and I average about 45MPG during the summer, about 35MPG during winter with the snow tires on. Best Mileage Ever was an even 50MPG. I kept track for 2 years, every gallon used. BUT, I drive about 95% highway, for trips of over 100 miles at a time. Average speed is usually about 60 mph. Yes, I'm the guy that gets passed all the time, but with gas close to $2 gallon for regular unleaded, I only wish I could have afforded that Insight in the showroom!
The box said "Requires Windows XP or better"... so I installed Ubuntu!
Check out this thread on a Prius users group to get some first hand, real world drivers experiences with the best car being manufactured right now!
Safety Cap is exactly right, you need to invest enough time and mental capacity to learn how to drive a hybrid (this is after all a very different system - it's not your father's Oldsmobile) but with just a little effort it is possible to beat the EPA figures.
Delivering militantly anti-commercial music to all two people who care!
I own a Civic Hybrid, and I've found that the way I drive severely affects the gas mileage, as others have already mentioned. A couple of things I'd like to add are:
* If you are driving uphill, never go above 55. The mileage up hills is much more related to speed than on flats.
* I drive to work every day 85 mph on the freeway, and through city traffic. Ok, so I get 42 MPG, which is not the advertise MPG, but so what - find any other car that gets 42 MPG under those conditions.
LS
There is a fine line between being a cultivated citizen and being someone else's crop. - A. J. Patrick Liszkie
I have owned my 2004 Prius for about six months. During a typical week, where most of my driving consists of the commute to and from work, my gas mileage ranges from 46 to 49 mpg. I live in San Diego, California and the drive has a lot of up and down stretches which may tend to keep the numbers down. My best mileage is on the freeway during the rush hour commute. With speeds down around 15 mph, the car spends a significant part of the drive running on battery only. Unfortunately (or fortunately) my work schedule has me doing most of my commuting during non-rush hour times. During one week however, when I did have a 9 - 5 work schedule, I averaged 52 mpg as reported by the dashboard MPG readout. My wife and I have made one 840 mile round trip to Nevada since we have owned the car. We averaged 49 mpg on the trip with speeds in the 65 - 75 mph range. When I bought the car, I didn't expect to get the EPA mileage. Considering that I haven't changed many of my driving habits since I got the Prius, I am very happy with the mileage that I am getting.
Hybrids that use gasoline are __still using gasoline__. They don't even claim as good mileage as the Volkswagen diesels get. A small car running on biodiesel is a huge improvement over any of the gasoline hybrids currently available, in terms of dollars spent and environmental impact. Volkswagen claims their TDI engines can run any blend of biodiesel (b20-b100) without modification, and petroleum based diesel where biodiesel is not available. The Smart Car CDI engines should be able to run biodiesel, but I have not seen any mention of this. Smart Cars are not available in the US until 2006, but Canada and Mexico both import certain models. Smart cars are inexpensive and very fun to drive, and get probably the best mileage of any production car. Most diesels can run biodiesel without modification, it actually has better lubrication properties when compared to petroleum based diesels, without the need for added lubricants. see http://www.biodiesel.org/
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Only if your engine requires it. Buying hi-octane gas for your Toyota and expecting it to "run better" is wishful thinking. If it pings using the regular stuff, your engine has other problems, such as carbon buildup. Otherwise, you're just wasting money. BTW, there is no inherent "quality" difference in lo- and hi-octane fuel. Higher octanes are less prone to predetonation (pinging), and therefore are better suited for high-compression, high-performance, i.e., more expensive, engines.
Huh? Are you doing the same math as the EPA? Yes diesel has more energy per gallon, it is cheaper, if used properly its cleaner and heck its safer too!!! So I will continue gloating.
As for MPG being misleading? Uh if I pay 1 dollar for a gallon of diesel and go farther then a gallon of gasoline, well you do the math cause last time I did I saved money which I can spend on solar panels (but that is something altogether differnt).
The batteries can be recycled also.
They last longer then NiCd batteries.
Have higher energy densities.
No memory effect.
Plus they aren't toxic like NiCD
The big negative is that they discharge quickly.
Veramocor
Not to mention, if you do the math on the gas savings, it takes nearly 150,000 miles of driving to make up the cost differential between the hybrid and conventional models of car, assuming that they get 50 and 30mpg respectively and that gas costs $2 a gallon (yay, USA).
It's worth a mention, though, that as far as the article is concerned, there doesn't seem to be much statistical data concerning lower mileage, only a few anecdotes. Consumer Reports (according to the article, not the posted story) apparently found hybrids to measure pretty close to their government rating.
Under capitalism man exploits man. Under communism it's the other way around.
Really...10% thermally efficient? As in put in 100 Joules, get out 10 Joules?
Obviously, you need to do more researching. Under overheated condtions, I've gotten as low as 50% efficiency storage of NiMH batteries, never down to 10%. If you keep them decently ventilated, that way back up, to somewhere around 90% if my memory serves me right.
I know that no commercial hybrids use Lithium Polymer batteries yet, but if they did, the thermal considerations would be almost non-existent, and the efficiencies would be higher too.
As for fuel cells, don't even get me started. There are so many problems (physical storage, commercial distribution systems, warm-up times, low power, etc.) that it'll be a long long time until we see anything like that on the road. Besides, the "low power" issue (they always put out constant power, unlike the internal combustion engine, which can be throttled) means you can't control your torque...the only way around that is to hybridize it and use battery storage as well.
"Cold makes rubber stiff, so tires absorb more power."
Er, what? So the most fuel efficent tires would be soft and squishy?
Just from that statement alone you're making me disregard everything else you've said.
Democrats or Republicans. They are both taking us to the same place and they are not afraid of us anymore.
(OK I may be redundant, but after 900+ commments, I'm bound to miss a few)
The focus of hybrids is not necessarily efficiency; it's EMISSIONS that, IMHO opinion, are the focus. Are there cars that get better mileage? Sure. A Geo can get better mileage than my car, but does it have the ride and comfort level? My 2003 Prius gets around 45-50 MPG in mixed driving (at a curb weight of about 2700 pounds mind you), with a recent tank pulling about 60MPG (570 miles and no matter what I did, I could only squeeze 9 gallons into the tank. Even tried a different pump).
The window sticker states 38-52 highway, and 44-60 city MPG. Driving conditions and habits are a MAJOR influence on driving habits. No technology can compensate for jackrabbit starting, long idling, speeding, or poor maintenance.
From the window sticker:
"Actual mileage will vary with options, driving conditions, driving habits, and vehicle's condition. Results reported to EPA indicate that the majority of vehicles with these estimates will achieve between 44 and 60 mpg in the city, and between 38 and 52 mpg on the highway."
Even hybrids idle the engine periodically, especially in winter. This is to keep the engine and catalytic converter warm, minimizing emissions. Yes, they will sacrifice a little gas to keep the components warm and operating at maximum emissions efficiency. The net emissions output is lower since all is kept warm vice allowing to cool an re-warming.
My Prius is rated at 45MPG highway, and I sure get that and then some. BUT...I shouldn't expect to get the same economy if I zip around at 75MPH as I do at 60 or 65MPH. I'm no EPA mileage expert, but I suspect that the test loop only has cars runnign at most 60MPH, windows closed, no A/C running, in other words, near optimal economy conditions. Anybody have better info?
Also, it needs to be known that short trips hurt the economy of ANY car, hybrid or not. Hybrids still take time to warm up, and during my car's 5-10 minute warm-up period the engine is always running, hurting efficiency.
In short: the EPA estimates are not gospel; hybrids do deliver efficiency, but focus on emissions at the first priority of the technology.
Government's idea of a balanced budget: take money from the right pocket to balance...oh who am I kidding?
Actually, you're probably less safe on a bicycle than a motorcycle on the street. A motorcycle is bigger and fairly well-lit, so it's more visible to people driving cages. It can also move with the flow of traffic(*) - it's not speed that kills, it's speed difference;-) Personally, I think that everyone should be required to start on a motorcycle when they get their license at age 17, and only be allowed to move up to a car after a year or two. That would give them some personal experience as to why driving like an idiot is bad.
-Drew
(*)-> I've actually moved faster than the flow of traffic on a bicycle, but that was during rush hour on a major 2-lane road in NJ, weaving along on the shoulder. This was sort of fun, but also sucked because breathing fumes ain't fun, and I also had to deal with glares from pissed-off cagers who were annoyed that I was somehow cheating at their game.
while the chemical reaction in a battery could be highly temperature sensitive, it isnt
Here's a test for you:
1) Take some alkeline batteries for a flashlight.
2) Put them in the flashlight and observe the light level.
3) Remove batteries and place in freezer overnight
4) Remove batteries from freezer and replace in light
5) Turn on flashlight. Notice lower/no light is coming from flashlight.
Chemical reactions slow down in colder temperatures. It's just that lead-acid batteries for cars, especially in northern climates, are WAY overpowered, in order to deal with the cold (and to give them longer life). Cold cranking amps, it's what to check when you're buying a battery in the north.
Most warmers do warm the oil, but they keep the whole compartment a little warmer as well. Oil is the bigger problem first though.
I wouldn't want an electric when it hits -40 here. I'd use up the batteries just for the heater!
I don't read AC A human right
When you first start your car's engine, most of the oil is sitting at the bottom of the crankcase below the level of most moving parts. What little oil that always remains up near the piston rings and such will be more viscous, but it makes little difference.
However, the ion mobility (and thus peak current) are very strong functions of temperature. Specifically, the electorlyte density and viscosity increase, which increases the internal resistance of the battery significantly. And while lead-acid batteries have a almost constant no-load voltage for any temperature, the increase in resistance severly limits the current available to the starter. The normal resistance of a discharging battery is ~0.001 ohm, normal starting current for a medium car can be ~50-60 amps, any significant increase greatly reduces the effective voltage and current.
A block heater in the car's engine bay will help heat the whole bay, but mostly serves to reduce the wear and tear on the piston rings and bearing races that would otherwise occur while the cold oil heats up and gets sloshed around the inside of the engine. Since the oil is already warmed, it can get into the moving parts more quickly. Large engines (think ships) use oil heaters even on hot days to protect the rings and bearings
.
90% of my driving is highway. My Prius gets 49 MPG average.
By the way, automatic transmissions have gotten a lot better in the last eight years.
I drive a Honda Civic HX CVT coupe and I get 34-37 mpg daily, thanks to the fact on a continuously-variable transmission you are more or less using the most efficient rev speed regardless of load you're applying (acceleration, cruise, and so on).
There are definitely two things you can do to improve fuel efficiency besides changing your driving style:
1. Change your air filter regularly. By changing the air filter at least twice a year you improve breathing of the engine, which means better fuel mileage.
2. Make sure the tires are properly inflated when cold. This means at least once a week check the inflation pressure of the tires in the morning before you drive the car for the day; make sure they match what the car manufacturer recommends (there's a sticker on the car either on the inside of the glove compartment box or on the door sill that recommends the cold inflation pressures). Properly inflated tires mean lower rolling resistance, and that can improve fuel efficiency by as much as four percent!
3. Keep the fuel delivery system reasonably clean. I'd recommend using something akin to Chevron's Techron additive about three times a year to keep the fuel injectors clean, and use something like Gumout to keep carbuerators on older cars clean on a regular schedule. Dirty fuel delivery systems can rob engine performance and fuel efficiency very quickly, to say the least.