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Hybrid Cars Don't Live Up to Mileage Claims

Posted by timothy on from the my-wagon-slurps-gas dept.

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."

27 of 1,528 comments (clear)

  1. Better than nothing by Lord+Grey · · Score: 5, Insightful
    It looks like these cars are more hype than help in the battle against pollution and foreign fuel reliance.
    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.

    Personally, I'm interested in hybrids but not for fuel efficiency reasons. I'd like to see auto makers combine the output from different energy sources into all-wheel acceleration of a normal car. I remember seeing something on the news a few years ago about Ford experimenting with that on an Explorer, trying to jazz up the acceleration of a bigger vehicle. I don't know what became of that testing, if anything. But it would be extremely cool to see that technology in a small, sporty car.

    --
    // Beyond Here Lie Dragons
    1. Re:Better than nothing by laupark · · Score: 5, Insightful

      Also, add the environmental cost of gigantic batteries that these things will discard every five years (or has that been addressed?)- really, I don't know if it has, but I always wonder about the environmental impact of the battery production and destruction.

    2. Re:Better than nothing by stanmann · · Score: 5, Informative

      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
    3. Re:Better than nothing by daviddennis · · Score: 5, Insightful

      It would be, but I think the EPA cares more about emissions than fuel economy. You could say the economy figures are a (theoretically at least) useful byproduct of the emissions testing they already have to do.

      D

    4. Re:Better than nothing by glitch! · · Score: 5, Informative

      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...
    5. Re:Better than nothing by Glonoinha · · Score: 5, Funny

      Yes but you have to remember - your buddy's Escort gets 31MPG and the Hybrid car may get 31.5MPG - but the Hybrid's mileage is 31.5 environmentally friendly miles per gallon of gasoline where your bud's Escort's mileage is 31 environment destroying miles per gallon.

      Miles per gallon of gas in a Hybrid car are way better for the environment because the Hybrid also uses electricity, where miles per gallon of gas in a regular car are bad for the environment because of emissions, resource depletion, depending on OPEC, all that stuff.

      Big difference. Or so the Honda ads would have me believe.

      --
      Glonoinha the MebiByte Slayer
    6. Re:Better than nothing by Doc+Hopper · · Score: 5, Informative

      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

    7. Re:Better than nothing by dasmegabyte · · Score: 5, Interesting

      YMMV is correct. Why it varies is important.

      On the highway, a Hybrid engine is just a low-powered gasoline engine -- generally, the electric engine does not engage over highway travel. I say low-powered, and not under-powered, because today's engines have an obscenely high average horsepower. An "economy" car like a Civic or a Focus has a better power to weight ratio than many classic V6s. Your '69 Type 1 put out 55 horsepower, which was plenty to get 4 passengers and their gear up to 75 MPH.

      As a low powered gasoline engine, you get your best economy by accelerating slowly and allowing the resistance of the engine to adjust your speed. Braking on the highway, or downshifting before accelerating, will take a huge bite out of your economy.

      It's in city driving where the hybrid shines, but again, only if you drive it correctly. The big thing is to try to keep the gas engine shut off as much as possible. This is performed by accelerating slowly from stoplights and braking slowly as well (more energy is recycled by the magnetic brake when less is lost to the "backup" brake). Jackrabbit starts will be tempting, as the electric assist engine has a TON of torque, but resist it! That's the only way you'll see your economy improve.

      To be honest, these driving methods will help you improve the economy of any car, especially 3 and 4 cylinder engines, where keeping the revs low and speed constant has a bigger effect than with a 6 or an 8. But the difference in economy is even wider for a hybrid. Whereas I can see an 8 mpg difference between racing to work (27 mpg)and driving casual (35 mpg) in my turbocharged I4, with a hybrid that difference could be close to 20 mpg.

      The EPA drivers know how to drive efficiently, and that's why their scores are so high. You can learn to drive like this too...it's why the Insight has a momentary MPG rating right on the dashboard. The guy from AutoWeek who did the long-term Insight test said he considered the average MPG rating to be a "different KIND of performance rating," and that he made it a game to get it above 60.

      --
      Hey freaks: now you're ju
    8. Re:Better than nothing by jumpingfred · · Score: 5, Insightful

      Careful driving in a regular gas car vastly improves the millage also.

    9. Re:Better than nothing by Misch · · Score: 5, Informative

      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
    10. Re:Better than nothing by Master+Bait · · Score: 5, Informative
      I'm getting 52 on my ancient 1982 diesel Jetta with a normally-aspirated 1600cc engine. I have also clocked about 365,000 miles on the original engine.

      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
    11. Re:Better than nothing by cluckshot · · Score: 5, Interesting

      Since my work is researching HEV's and I keep pretty well up to date on the tech, I might have a point or two.

      HEV's are a passing technology an interim beast which really is already out of date. They never would have existed if the numbers had been balanced. HEV's in battery storage cannot be more than about 10% thermally efficient. That's pretty rotten considering that they must do that downside of the engine efficiency. They do have the advantage of allowing Electricity to charge them up when parked. The energy efficiency issues hit this too.

      There is a far better technology coming right away. It is a Fuel Reformer/Fuel Cell combo. It has all of the advantages of storing braking energy etc and none of the difficulties with batteries etc that correspond in scale to the Prius etc.

      Military interest in Hybrids is related to dual use of the generator. There is also stealth.

      I expect that a civilian buying a hybred thinking they are saving energy or getting a good deal is going to get stuck. The technology just isn't that good. There are exceptions to this. If you are a route driver like a mail currier you will win with a hybrid. If your commute is a lot of stop and go stuff with long periods of stop or very slow driving, it pays off. The more long high speed driving you do, the less value the hybrid is going to have.

      --
      Never Politically Correct ~ I prefer the facts If you don't like what I say, get a life, or comment yourself.
  2. ...so are non-hybrid cars also overrated? by Harmotech · · Score: 5, Interesting

    I didn't see this answered in the article, but are other gasoline-only autos also overrated?

    I mean, if the same EPA testing standardis used on all cars, and the hybrids are overrated...

    That said, I have an '88 Volvo that I watch the mileage of pretty closely, and I get b/w 25 and 30 mpg. And it's a big heavy bastard...

    hmmmmm....

  3. Biodiesel baby by wherley · · Score: 5, Informative

    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!

    1. Re:Biodiesel baby by Woogiemonger · · Score: 5, Funny

      Exhaust smells like french fries!

      If there's anything that's gonna sell Americans on biodiesel, it's gonna be the smell of fast food.

  4. I always got ~55mpg with my Honda Insight 2001 by AdrianZ · · Score: 5, Informative

    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.

  5. These hybrids by LOL+WTF+OMG!!!!!!!!! · · Score: 5, Interesting

    Have quite a bit less power than their gas-only counterparts (like the hybrid Civic). I've seen people trying to drive these things like they're race cars, and that certainly isn't going to help.

    MPG estimates are easy to reach when drive like a responsible person, and according to the cars manual. This is often a bit slower than you are comfortable with, hence the problem. It just happens to be that the rift between gas waste with the two driving styles is quite larger with the hybrid engine.

    Drive nicely, you're mileage will be a lot better.

    --
    That CSS file that blocks ads
  6. Re:Why I Didn't Buy a Hybrid Car by afidel · · Score: 5, Informative

    In reality the best price/pollution ratio today is a small turbodiesel. The best example is the Volkswagon Jetta TDI, the Jetta gets real world numbers within 20% of the hybrid's claims (probably higher than the real world performance of the Civic Hybrid for example). Modern turbo diesel engines have eliminated most of the historic problems of diesel engines (soot mostly) but they still have problems with NOX emissions.

    --
    There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
  7. A message I posted to a friend a while back... by Dr.+Evil · · Score: 5, Informative

    The Honda Civic Hybrid is an example of a hybrid is set up with the following:

    • A smaller than normally practical internal combustion engine
    • A continuously variable transmission to drive the wheels forward
    • Improved aerodynamics
    • An Aluminum chasis
    • Electric motors on each of the wheels to generate power while braking and to assist the IC drivetrain

    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:
    http://www.fueleconomy.gov/feg/bymodel/1992_Honda_ Civic.shtml

    2004 Civic line (including hybrids)
    http://www.fueleconomy.gov/feg/bymodel/2004_Honda_ Civic.shtml

    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)

    1. Re:A message I posted to a friend a while back... by Eivind · · Score: 5, Informative
      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.

      It does. A fairly typical family-car has 120ps and a 1.6 litre engine. Even though, 90% of the time it uses only a fraction of that power, the power is "needed" because people expect acceleration and ability to climb short hills without loosing speed.

      With an electric assist that can give an additional push, powered from batteries for short periods, a weaker engine can be used. And here's the thing: a weaker engine is more economical.

      Under circumstances where you need 35ps (for example 100km/h on flat highway) a 50ps engine is going to consume less fuel than a engine capable of 120ps, but currently near-idling at 40ps.

      This is so for various reasons, partly that it requires energy to pump all that air in and out, and partly that there's a lot more mass to move in a bigger motor, which tends to lead to more internal friction-losses.

      On the flipside a hybrid will tend to be heavier, because it essentially has two engines (though smaller) and two energy-storages.

      Still, hybrids *do* get more mileage than conventional autos with comparable performance. Just not as much extra as the EPA-estimates will have you believe.

  8. Overblown by the media... by mbbac · · Score: 5, Interesting

    Perhaps the Civic isn't as great as the EPA rated. I don't know, I'm not interested in one. However, Randy Rathbun's blog had a mileage log that contradicts this story at least as far as the Prius (the only hybrid I'm interested in at this point) is concerned. I trust his empirical evidence more than a poorly researched article that paints all hybrids with the Civic-brush.

    --

    mbbac

  9. Not better than Diesel by Enigma_Man · · Score: 5, Insightful

    Honda has a new Diesel powered car that isn't a hybrid, and is getting 76 MPG (U.S. gallons) in real-world testing by the FIA. It's also breaking speed records for its class in the FIA testing (with the exact same cars used for the fuel efficiency test). I'm curious as to why diesel powered cars aren't more popular in the US, they can be much more efficient, and with recent advances in catalytic converters, and technology, these new diesel engines run very clean and very quietly.

    There's no batteries to worry about, and you get a fullsize (well... not subcompact like most hybrids anyway, hehe) car with a full trunk to use.

    -Jesse

    --
    Nothing says "unprofessional job" like wrinkles in your duct tape.
    1. Re:Not better than Diesel by jridley · · Score: 5, Interesting

      I heard (also on NPR) a few weeks ago that most of the pariculate emissions from diesel could be vastly reduced by using low (or zero) sulfur fuel. The EPA would like to have mandated the new fuel by now, but the trucking industry is heavily against it. They're going to mandate it anyway, I think starting in 2007, perhaps rolling from CA eastward.

  10. Re:Duh by Technician · · Score: 5, Interesting

    Now for some truth. (disclaimer I drive a hybrid) On the freeway, the hybrid system doesn't do much. It's all plowing wind and the engine never shuts down.

    However in city traffic jam traffic, it shines big time. That awful creep and stop at metered on ramps and passing the wreck is usualy done with the engine off most of the time. This is where regular cars are very ineffecient. Unfortunately most of our time on the road isn't in these conditions in the USA. Now as part of the reality check, I have missed the EPA estimates by about 10 MPG. It's still double the milage I got on my last car. At current gas prices, the payback period has droped from never to something in the car's lifetime. If gas goes up more, the payback time will shorten much more. I don't regret my used Prius purchase.

    I replaced a 2.3 Liter 4 cyl Ford Mustang with a 1.5 Liter Toyota Prius. Mpg went from 24-28 to 43-48 for my commute. Getting 400 miles on a tank is normal. I haven't risked running out of gas to try for 500 miles, but I've had enough gas left at the next fill to have done it.

    The big savings I found for mine is as a standby generator. During an outage, I ran a TV, refrigerator, lots of lights, and chest freezer off the car. The engine did not run all the time. It would start, cycle for a few minutes and shut back down. Overnight my best guess is I used 2 gallons of gas. Most portable generators would require a refill every 3-6 hours to do the same job. At that consumption rate, I would not worry about refilling it for several days of constant running as an emergency generator. That could never be done with a conventional car.

    --
    The truth shall set you free!
  11. Hybrids a Hoax...sort of... by JawzX · · Score: 5, Interesting

    Hybrids ARE great for city driving, when the maximum power output of the drive line is almost never required. The batteries can happily slog through traffic for quite some time without needing to run the IC engine. However, high speed highway driving, merging, and passing will often require 100% of available drive line power, this is where hybrids fall down.

    Running both the engine and the electrics drains the batteries, requiring the engine to continue to run even after 100% power is not required, the engine has to run fairly hard to charge the batteries back up, and of course there is a loss of efficiency in the conversion from mechanical to electric energy. If you drive like grandma, your hybrid *might* reach the claimed highway efficiency, but at the cost of speed, merging and passing.

    Just for comparison my 1992 Alfa Romeo 164s has a 220hp fuel-injected 3 litre V6, asside from the BOSCH Motronic 5.1-ML injection, it is a decidedly low-tech engine. Single overhead cams, 12 valves, 60 degree, the valve train and geometry of this engine date from the mid 60s. The 164s weighs 3650 lbs, roughy TWICE what a Honda Insight weighs. The Alfa also features leather interior, kickin' sound system, very good aerodynamics, and a top speed in excess of 155 mph. If I take this beast on long highway drives, I can manage 31 mpg. The reason? Most the time the engine is using only a small fraction of it's possible power output.

    When a hybrid, or for that matter, any underpowered vehicle gets out on the highway the conditions often require the drive line to run at maximum output. No mater how lean burning or smart a fuel injection system is, it has to deliver more fuel to produce more power. But if a 3650 lb luxury/sport sedan can get 30+ Mpg why can't an 1800 lb econo car get 60+? The answer is it CAN. And without the added weight, cost and expense of hybrid systems. Hybrids are *a* solution, they are not however in my oppinion the *best* solution.

    What we need are high effiency small-ish engines in the 1.2 to 1.8 litre range put into light weight, aerodynamic bodies. The results would be affordable, reasonably fun to drive and just as efficient as hybrids for most American drivers. Those living in cities may want to consider a full electric solution, or *gasp* public transportation (which is, unfortuneately not really up to snuff in most American cities). In addition, a displacement on demand system could improve the efficiency of small cars in city driving as well. Who says only a V8 would bennefit from this technology? A small 4 cyl car could conceivably be set up to idle on only one cylinder at stop lights.

    Hybrids may actualy be better suited to high performance applications than high efficiency applications. Witness the Toyota Volta. The Volta is efficient because it rarely uses 100% of it's available power, and since about 50% of that power is provided by electrics, it's IC engine is similar in efficiency to that of a vehicle with 1/2 the total drive-line power of the Volta. The result is a vehicle that rarely taps it's full potential, and operates at maximum efficiency most of the time rather than maximum output.

    --
    A Call For A New Slashdot Moderation Level!
  12. Engineer off his rocker by Doc+Hopper · · Score: 5, Informative

    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

  13. Prius Mileage by kmassare · · Score: 5, Informative

    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.