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Technology Science

Hybrid Drivers Provide Real-World Mileage Data 1167

Jason Siegel writes "Hybrid cars seem like the answer to rising gas prices, increased pollution and growing dependence on foreign oil, yet EPA tests have failed to produce reliable mileage estimations for consumers. Dependable fuel economy figures are now available at GreenHybrid.com, where hybrid owners have logged over 5,000,000 miles of driving information in real-world conditions. Unlike government tests and individual accounts, the database analyzes thousands of actual experiences to provide true mileage statistics." Read on for the rest.

The hot-selling Toyota Prius averages 48 miles per gallon among over 150 cars from across the country, with most drivers achieving between 45 and 51. The V-6 Honda Accord Hybrid delivers 30 miles per gallon while Ford's Escape Hybrid SUV averages 28. All hybrid owners are encouraged to post their data for these and other cars on the Internet's largest hybrid mileage database.

Reliable fuel economy figures are increasingly important as consumers explore their options in an emerging hybrid car market. Hybrids, like the new Lexus RX 400h, pair combustion engines with electric motors that recharge while driving to improve gas efficiency. "Until lately," said GreenHybrid creator Jason Siegel, "consumers have associated hybrid vehicles with a small niche of fuel-conscious environmentalists, but today's hybrids offer the best combination of high performance, great mileage and luxury features of any cars on the market."

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Hybrid Drivers Provide Real-World Mileage Data

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  • MPG science (Score:5, Interesting)

    by suso ( 153703 ) * on Monday May 09, 2005 @09:31PM (#12483822) Homepage Journal
    You know, I'm starting to wonder if some of those gas saving tips like "start and stop slowly" have been backed up with real world testing. I just spent the last three weeks testing the hypothesis that "driving smoothly" (ie, starting up slowly and anticipating stoplights, etc. saves a lot of gas. Here was my test. By the way, I have a 2004 Honda CR-V that gets a rated 24 MPG Highway:

    • Fill up tank with gas (til the auto stop turns off)
    • Drive smoothly for the whole tank (tried to never let RPMs go above 2500)
    • At end of tank, calculate gallons to fill back up and miles traveled
    • Drive through another tank of gas, but this time very agreessively.
      Basically, I floored it when taking off and took the car to the max.
    • Make same MPG calculation at end of tank.

    You know what I found, I got 25 MPG in BOTH cases. In fact, I got slightly better milage when I was agreessive. Granted, this was not completely scientific, but it made me wonder about doing more accurate testing. I expected to see a 5-10 MPG difference. To follow up, I drove the last tank at a normal "in-between pace".

    I was talking to someone at work about it and they thought that maybe today's engines are tuned so well and change with different environments that it doesn't make a difference. It only makes a difference if you are stopped a lot like in traffic jams.

    Anyone in Central Indiana want to join me for some more scientific testing?
    • Re:MPG science (Score:5, Interesting)

      by avalys ( 221114 ) on Monday May 09, 2005 @09:34PM (#12483846)
      One thing that does make a difference is how fast you drive on the highway. I know I get much worse mileage driving at 80-90 than I do at 60-70.
      • Ok, that is what I've heard a lot of people say as well. I thought I had the same intuitive feeling about "driving smoothly" as well, until I measured it. Maybe you should measure it sometimes. Of course, driving faster has other incalculable impacts such as paying for tickets, higher insurance and accidents.
        • by coyote-san ( 38515 ) on Monday May 09, 2005 @10:23PM (#12484270)
          Mass carnage was predicted when the double nickle speed limit was dropped. In fact the accident rate WENT DOWN.

          There were several reasons for this. N.B., all of these were predicted by the proponents for the change, but dismissed by the safety "experts."

          First, anyone with a clue knows that the biggest threat on the highway is traffic traveling at different speeds, not the absolute speed. People tend to stay in their own lanes - and can even comfortably stay in the right hand lane - if everyone is travelling at about the same speed. But if there's a 20 mph range (which was common in the interurban areas of the square states) there will be a lot of lane changes even when traffic is relatively light. At those speeds just tapping a car may be enough to cause the driver to lose control.

          Second, a realistic speed limit actually lowered the speed of the fastest drivers. A driver going 20 mph over the posted speed limit doesn't have much motivation to avoid going 30 mph over the posted speed limit. But the same driver at the same original speed, if it's the speed limit, will often stay at that speed.

          Finally, these roads were designed for traffic going at ~70 mph. At those speeds the road has just enough variability to keep the driver's attention. At the slower speeds the roads are mindnumbingly boring and the driver's attention tends to wander. You wouldn't think it would make that much of a difference, but I've driven between Denver and Seattle at both 55 and 75 and there is absolutely no comparison. (I-80 thru Wyoming and the Columbia River Gorge still suck because they were long, straight flat segments.)

          That's why the death rate went down when the speed limits were raised. The annual death rate is climbing again, but that reflects more passenger-miles.

          P.S., the Colorado Dept of Transportation will actually adjust the speed limit to match the drivers, not the other way around. They feel, reasonably, that thousands of drivers will make an informed decision about the best speed for a segment of road. Sometimes their hands are tied because of regulations, but I've seen them change the speed limit on other segments.
          • by Dashing Leech ( 688077 ) on Monday May 09, 2005 @11:22PM (#12484684)
            "In fact the accident rate WENT DOWN." "That's why the death rate went down when the speed limits were raised."

            Not that I disagree at all, but there is a common assumption or mis-conception that you seem to be repeating here, unless you have a separate source. A lower accident rate does not mean a lower death rate or vice versa. It might be true in this case, I'm not sure.

            The argument about relative speeds being the problem probably has a lot of truth in it; I've read research in this area and it certainly seems to be a factor. However, reducing the disparity by raising the speed of the slower drivers means that there is much more kinetic energy on the roads, especially with kinetic energy increasing with the square of velocity. (20% faster speed means 44% more kinetic energy.) This is further exacerbated by a trend towards larger vehicles, such as SUVs, since kinetic energy is also proportional to mass. In an accident this energy must be dissipated and the amount of damage will generally be related to this energy.

            So, while accidents may happen less often, the average and total damage caused in an accident may increase, including death rates. Accident rate is only part of the equation. Again, the death rate may have indeed dropped, but it isn't a given just because the accident rate dropped.

            • by Afrosheen ( 42464 ) on Tuesday May 10, 2005 @12:15AM (#12485091)
              Something like this is really hard to qualify because there are so many factors involved.

              Due to structural crush zones in cars, additional airbags, antilock braking systems, door beams, and other safety features in even cheap cars, accidents are much more survivable than they were even 20 years ago. However, with the trend in this country towards gigantic SUVs for every soccer mom, it may be equally counterbalanced.

              The US DOT would have you believe that slower is safer, which it may be in densely populated urban areas. However, in mind-numbing interstate travel (I just made a 742 mile trip last Tuesday and again on last Saturday), you want to go as fast as your car feels safe traveling. This does increase your attention and focus, because you are forced to react to changing terrain more frequently and you realize the margin of error shrinks at higher speeds. I.e. you achieve a slightly higher 'pucker factor'. ;)

              There is a limit as to how fast you can safely travel which is mainly governed by how quickly you can stop. Sport Compact Car magazine recently reviewed a race-ready Mitsubishi Evolution 8 with upgraded everything including a beefed up braking system. The stopping distance from 60-0 was an unheard of 98 feet. From 70-0 it increased slightly to 135 feet. Now, from 80-0 we see a shocking increase to 179 feet. 20 mph, 33% faster and you effectively double your braking distance! Keep in mind this is on an exceptional car, real world, average cars come nowhere close to these numbers. Stopping from 60mph in 98 feet would sling the snot out of most people's noses.

              Perhaps you're right about 20% faster speed nearly doubling kinetic energy, as that's what the braking system is being forced to deal with and would definitely cause those numbers to nearly double.
              • One of the great traffic safety myths is stopping distance. Who cares if your stopping distance is 200 feet or 300 feet?

                Personally, I think putting so much emphasis on stopping distance is a mistake. We spend a lot of time teaching drivers that they need to be able to stop before they hit something, and that's not true. You need to be able to STEER to AVOID the accident. I've witnessed on more than one occasion a driver get into an accident that could have been avoided by NOT braking and turning (doing
                • by -brazil- ( 111867 ) on Tuesday May 10, 2005 @06:32AM (#12486652) Homepage
                  Damage caused on impact with a stationary object increases linearly with speed (well, at least, damage to you).

                  Wrong. Please get a grip on basic physics.
                • by tgd ( 2822 ) on Tuesday May 10, 2005 @07:14AM (#12486832)
                  Virtually every accident I have witnessed that was clear caused serious property damange, injury and death (seen a few of those, unfortunately)... nearly 100% of those, if not 100% were people trying to swerve around slower or stopped traffic.

                  Why is that? People in the US are not taught how to control a car, they are only taught how to interact with other cars on the road. Watch someone who is a professional or amateur race driver (who understands vehicle dynamics at the limit) in those situations -- they react totally differently. Threshold brake, keep the ABS from engaging, and stay in a straight line. If you can't scrub the speed to the point where the impact will be a non-event (5mph), you were following WAY WAY too closely. Better to hit the car softly than risk oversteering into it, or worse understeering off the road or into another traffic lane. Once a car starts to lose traction, it takes a very skilled driver to make it go where they want it to.

                  If you don't know the reasons going 100mph is unsafe for most drivers no matter what the road conditions, you're not in the "knowledgable driver" camp. 100mph is dangerous in any situation in 99% of the cars on the road. Its not how the car and driver can handle expected situations, its how that car and driver can handle an unexpected one. In virtually every case, at 100mph they can't.

                  Two speed limits isn't the answer. Requiring something more than ten hours of on the road driving and 30 hours of classroom time is the answer. Require limited traction training the way many european countries do. Or maybe just even mention the concept of a traction cirle to young drivers and explain why their lives may depend on them understanding it. A properly trained driver can be in just as much control of a car with four wheel sliding as a badly trained driver on dry pavement.

                • by Halo- ( 175936 ) on Tuesday May 10, 2005 @09:47AM (#12487876)
                  One of the great traffic safety myths is stopping distance. Who cares if your stopping distance is 200 feet or 300 feet?

                  Okay, I agree that in some conditions stopping distance isn't the be-all and end-all of safety, but I still care deeply. The problem isn't "good" drivers. The problem is average-to-poor drivers. Knowing what to do in a panic and actually doing it are two very different things. Almost everyone knows you "steer into a skid" but how many people do that instinctively?

                  The problem is that most drivers are going to react linearly to threats. Basic amimal instinct is to stop and assess. Steering out of a situtation, or even speeding up to avoid a crash are often viable options, but they require that the driver have awareness and confidence not only of the road in immediately in front of them, but also to the sides and behind them. The simple truth is that 90% of drivers don't pay that sort of attention consistantly. When something unexpected comes up, they hit the brakes. "Slow down, let me think" is too deeply ingrained of an instinct to train around.

                  Traffic laws have to be made for the lowest common denominator. Unfortunately, this is often the distracted parent in a huge vehicle full of screaming kids with a cell phone in his or her ear. I don't like it, but I don't think there is anything which can be done about it.

                  • "Almost everyone knows you "steer into a skid" but how many people do that instinctively?"

                    Especially when you're driving a friend's car and all your reflexes are trained for your own front wheel drive compact.

                    I'm not proud of it, but by the time my brain had recalled what I learned in driver's ed about handling a skid in a rear-wheel, we were sitting in the ditch, and my girlfriend had a new embarassing story to tell her family.
                • ". You can be 60 feet away from the car in front of you going 100 miles an hour and still stop in time."

                  This is true unless the car in front of you hits a stationary object (e.g. some wall) and slows down extremely fast.

                  You (as a driver) just have to hope stuff like that rarely happens and the risk*impact is worth it, otherwise you'd leave a much greater gap between the cars.

                  That said apparently some cars have very good occupant survivability for typical 60 mph crashes.
                • DANGERIOUS ADVICE (Score:3, Insightful)

                  by bluGill ( 862 )

                  True there are many times you could steer out of an accident. However there are many more times when you cannot.

                  A habit of hitting the breaks hard may sometimes result in an accident that is avoidable. However it will never result in an accident much worse than the one you were trying to avoid.

                  When you steer you have to prevent a rollover. You also have to have a clear place to go. Searing into oncoming traffic changes a 'simple' read end to a head on. Steering into a ditch may often mean hitting

            • Sometimes an indicator may be misleading.

              The army started issuing kevlar helments. The number of injured in the hospital went up.

              (jump to the wrong conclusion here)

              The soldiers survived attacks and went to the hospital instead of the morgue.
      • Re:MPG science (Score:5, Informative)

        by Hadlock ( 143607 ) on Monday May 09, 2005 @09:38PM (#12483878) Homepage Journal
        Which is exactly why the speed limit when from 70 to 55 durring the oil crisis. Someone will correct me, but wind resistance is cubed every time you double your speed. Our old '84 caddilac with trip computer got 25mpg at 64mph, but got 17-19mpg at 70mph. Closer to 28mpg at 55mph.
        • Re:MPG science (Score:5, Interesting)

          by barawn ( 25691 ) on Monday May 09, 2005 @10:09PM (#12484165) Homepage
          Which is exactly why the speed limit when from 70 to 55 durring the oil crisis. Someone will correct me, but wind resistance is cubed every time you double your speed. Our old '84 caddilac with trip computer got 25mpg at 64mph, but got 17-19mpg at 70mph. Closer to 28mpg at 55mph.

          Every time you double your speed, wind resistance quadruples. It goes with the square of the velocity.

          However, that's not the whole story by a long shot, which should be obvious. If the slower you go, the better gas mileage you get, you might think you get infinite gas mileage at a standstill. Of course, you don't.

          What makes the difference, then? Gears. See, your engine is extremely efficient in an RPM band - around the torque peak (called the power band). It's most efficient at the bottom of that power band. The gears don't actually help anything - as you learn in basic physics, simple machines don't change the amount of work that needs to be done. What they do is allow the engine to run at a more efficient RPM for a given speed.

          So what gears do is put peaks in the fuel efficiency curve. Depending on how a car is geared, 55 mph can be very inefficient, because it could be at the worst spot below the power band, which it is on my 93 Mazda. 55 mph gets me 28 mpg, whereas 65 gets me 30, and 70 gets me 34. 75 gets me about 32, and 80 gets me about 30 again (this is all measured).

          It's not just as simple as slowing down. You have to know how your car is geared - if it's got an overdrive, it's very possible that going 55 could hurt your gas mileage via engine inefficiency more than it helps via aerodynamics.

          That doesn't mean that 34 is the best gas mileage I get, of course. My peak gas mileage is in the mid-40s, in the peak of the previous gear (if I lock it into 3rd via the shift lock), where it's about 36-37 mpg. At lower speeds, aerodynamics losses are well below rolling resistance, so going slower doesn't help.
          • CVT (Score:3, Insightful)

            by interiot ( 50685 )
            Fortunately, the Prius [edmunds.com] has had a CVT [wikipedia.org] since it was released in 2001, so you don't have those peaks.
          • by Yaztromo ( 655250 ) on Monday May 09, 2005 @11:52PM (#12484911) Homepage Journal
            That doesn't mean that 34 is the best gas mileage I get, of course.

            I think you need to run some more tests there, as you should be able to do significantly better than that.

            For example, if you leave your car parked in the driveway and walk, you should get near infinite fuel efficiency at 0 kph. You only have to worry about evaporation and the natural breakdown of the fuel in your tank.

            (Sorry -- the mathematician in me decided to come out and be a smart-ass. The physicist in me would like to point out the the mathematician that we can do even better by putting the car in neutral while the engine is stopped and pushing it off a cliff -- you'll get ~9.8m/s^2 of acceleration without burning any fossil fuels whatsoever! Some days I just can't help myself...).


      • Re:MPG science (Score:5, Informative)

        by cornjchob ( 514035 ) <thisiswherejunkgoes@gmail.com> on Monday May 09, 2005 @09:47PM (#12483960)
        I know I get much worse mileage driving at 80-90 than I do at 60-70.

        That's because most transmissions in production cars have their highest geared tuned so that the engine's in its RPM sweet-spot around 60-70mph; after that, the amount of gas per RPM starts to increase considerably more.

        I'm curious as to just how high the grandparent kept his RPMs when he got similiar gas mileage driving timidly and agressively. Also, where has anyone heard stopping slowly increases mileage? Maybe in a car with regenerative breaking, but certainly not in a good ol' ICE powered car. If your foot's not on the gas, only idle gas is going to the engine (unless the computer is doing something, but it shouldn't affect that much). Unless I'm missing something, I can't see how slowing down gradually will increase anything beside the frustration of the driver behind you because you're not getting to a stop light quicker :-P
        • Re:MPG science (Score:5, Informative)

          by jayratch ( 568850 ) <slashdot AT jayratch DOT com> on Monday May 09, 2005 @10:04PM (#12484126) Homepage Journal
          The only reason stopping slowly helps MPG is actually similar to the concept of regenerative braking, albiet vaguely.

          When you stop abruptly, you will arrive at the stoplight more quickly (higher speed for longer) therefore there is a greater probability of it still being red when you arrive at it, therefore you are more likely to be at ~0MPH, thus requiring to accelerate your car from 0 to whatever your cruising speed is (hence more energy and fule needed.)

          If you ease off the accellerator when you first see the red light, you are a) not burning as much gas on your approach to the light, b) less likely to come to a full stop, and thus will have a smaller overall change in speed, less power required to return to cruising speed, less gas used. On the flip side, with this technique your chance of slowing down at a light is near 100% whereas in zero traffic, the abrupt stop method does give you a chance of zero change in speed, but you can only rely on that if you know the light timing and there's no traffic ahead to make you slow down anyway.

          Incidentally, when I slow down earlier, and roll up to the red light at 20mph, still at speed when it turns, vs hitting it at 45 a few seconds sooner and needing to stop all the way, I find by a block past the light I've passed virtually everyone who was stopped at it, and so in addition to being energy efficient I've increased my average speed too.

          Make sense?

          Re: last line of parent: There is no benefit, as described above, to "getting to a stop light quicker" if it is red; hence the driver behind you has no real reason to be annoyed. But yeah, I'm sure he will be. Ignorance here is less than bliss.
      • Re:MPG science (Score:4, Informative)

        by sillybilly ( 668960 ) on Monday May 09, 2005 @09:56PM (#12484051)
        You probably implied why, but just to make sure, let's state why: The air drag your car feels is proportional to the square of speed. Stick your palm out the window to test. At 1 mph almost none of the gas is spent on fighting air, because the air has time to get behind you. At such speed your gas goes to fight friction in the tires bending and relaxing, and the pistons, cylinders, gears rubbing up against each other inside the engine. But at 90 mph a very significant portion is spent on air drag friction on top of the tire and internal engine friction. The actual formula is

        F=1/2 * A * Cd * r * V^2


        F - is the force pulling your car or your palm back

        A - cross sectional area of your palm or car

        Cd - is the drag coefficient dependent on shape of your car or palm - i.e. do you look like a parachute or a bullet to the incoming wind, because even if you have the same square footage area facing the wind, its shape matters

        r - air density, dependent on temperature, humidity, barometric pressure/altitude

        V^2 - your velocity squared
      • Re:MPG science (Score:3, Interesting)

        by Phreakiture ( 547094 )

        One thing that does make a difference is how fast you drive on the highway. I know I get much worse mileage driving at 80-90 than I do at 60-70.

        I have a couple of empirical observations. These observations were made in a 1998 Subaru Impreza OS, 2.2L 4 cyl. boxer engine, 4-speed automatic, AWD. Some of the observations I have also made with a 1999 Chevy Prizm, 1.8L straight-4, 3-speed automatic, FWD.

        Normal driving on my commute, a six mile trip involving about one mile of 65MPH on a freeway, but most

    • Re:MPG science (Score:2, Insightful)

      by Skater ( 41976 )
      A lot depends on how much time you spent on the highway and what the weather conditions were. Also, how often is someone ahead of you at the light? For me, it's rare to be first in line, and you can't accelerate any faster than the car ahead of you does...
    • Re:MPG science (Score:3, Insightful)

      by ShaggyZet ( 74769 )
      I've actually heard that it may be better to accelerate quickly, if you know you're going to get to your target speed and stay there for a while (As opposed to stopping at another red light in 500 yards).

      I'll second the driver that said higher speeds make a huge difference. The Utah desert at 95-100 gave me terrible gas mileage, but it sure was a fun way to get to Vegas.
    • Re:MPG science (Score:3, Interesting)

      While timing things so you avoid getting up to 80 km/hr only in time to have to stop for a red light makes sense, avoiding hard acceleration is a bit of an anachronistic piece of advice.

      Old cars were carburated. When floored, lots of extra fuel would get dumped in the carb, and any that didn't get burned in the cylinders just got dumped down the tailpipe (possibly igniting, causing exciting backfire noises). So in the 70's oil crisis, we were all told to accelerate gently.

      Modern fuel injection has mad

  • But... (Score:4, Interesting)

    by TheOtherAgentM ( 700696 ) on Monday May 09, 2005 @09:31PM (#12483823)
    If you have to pay $5000 over the sticker price because of demand, are you really saving money? The demand is ridiculous.
    • Re:But... (Score:4, Informative)

      by Anonymous Freak ( 16973 ) <prius@driver.mac@com> on Monday May 09, 2005 @09:40PM (#12483891) Journal
      There are many dealerships that do not add a markup. If the one near you does, just say "Sorry, but I refuse to pay your luxury tax. You have lost any future business from me." and go somewhere else.

      Call all the Toyota dealers near you, even 200-300 miles away, I can almost guarantee that you'll find one in stock, at MSRP. (I only had to wait 2 days for mine. And it wasn't even 'ordering', it was calling all the dealers on Saturday, getting on their 'lists', and getting a call back on Monday saying they had 2 in stock that met my requirements (Blue, Tan, or Green, 2004 Packages 7 or 9, which are now called 5 and 6.) I drove a Blue package 7 Prius off the lot a mere 2 days after starting my search. (I could have had a top-of-the-line package 9, but it was in 'Tideland Pearl', which I mistakenly thought was green, it's more of an olive drab. So I picked the lesser-package 7 in blue, because I actually liked that color, and the extra features weren't important enough for me to want to wait.)
  • Accord hybrid (Score:5, Informative)

    by damiam ( 409504 ) on Monday May 09, 2005 @09:34PM (#12483849)
    Before anyone gets confused, I just want to point out that the Accord hybrid is not supposed to be super-efficient like the Prius. It's the top-of-the-line Accord, and the hybrid power is mostly used to increase performance while retaining similar fuel economy to the slower models. It's quite zippy; IIRC it has better 0-60 times than a V6 Mustang.
    • Re:Accord hybrid (Score:3, Informative)

      by subreality ( 157447 ) *
      The point is the same as any other hybrid: Better fuel economy at a given performance level.

      The Prius performs like a basic compact car with enough power to merge onto highways without feeling like you're going to be run over, but gets mileage more comparable to an underpowered econobox.

      The Accord hybrid has great acceleration for a sedan, but gets gas mileage comparable to a basic 4-banger compact.
  • by Yonder Way ( 603108 ) on Monday May 09, 2005 @09:35PM (#12483850)
    Turbo-Diesel owners have been seeing numbers in this range, or better, for years.

    Seems what the market needs is a diesel/electric hybrid to get numbers that will impress any diesel owners.

    Otherwise most TDI Volkswagens have been able to outshine these numbers for years. Plus you can't run a Prius on used cooking oil [greasecar.com].
    • by Leibel ( 768832 ) on Monday May 09, 2005 @09:49PM (#12483987) Homepage
      Quite agree. The Peugeot turbo diesel option (same Bosch direct injection technology) keeps setting world records. Their 307 just got 3.49 litres per 100km's (or 81.16 mpg in old money) according to this [drive.com.au] website. They averaged 1,700 Km per 60 litre tank! Why add all the complication of hybrid technology, or why not couple an engine like this with hybrid technology?
    • by devnullkac ( 223246 ) on Monday May 09, 2005 @09:51PM (#12484011) Homepage

      The one thing diesels tend to do poorly on is emissions, and California's emissions requirements are one reason automobile manufacturers are investing in hybrids. But even in the non-diesel arena, raw mileage isn't everything when it comes to this sort of thing: the Honda Insight gets much better mileage than the much heavier pre-2003 Toyota Prius, but the Prius has lower carbon emissions because the (very heavy) planetary gearing transmission lets it balance the load on the gasoline engine so that whenever it runs, it does so in the sweet spot to minimize pollutants.

    • by Cromac ( 610264 ) on Monday May 09, 2005 @10:01PM (#12484103)
      A diesel electric built along the lines of a locomotive would be interesting.

      For those who don't know in this case the diesel engine is basically just an electric generator that powers the electric motor. Because as a generator it can run at a constant speed it's even more efficient than a traditional diesel. It works for trains, I'd guess it would work for cars/trucks/SUV as well. GM/Allison has built buses this way that see a 60% MPG increase vs conventional diesel buses. If a Chevy heavy duty pickup sees a similar increase that would put it near 40 mpg on the highway. Pretty good for a 1 ton truck.

    • I totally agree, TDIs are quite efficient.

      Another thing we haven't seen quite yet is the turbine hybrid vehicle. We've had turbine powered vehicles in the past, but rather than gearing-down the turbine, I believe that you should be able to gain power from the rotating part in the turbine -- just by itself. I would assume that the unit would maintain it's rotation, and fuel/air ratios. I think capacitors come more into play than just batteries, as other electric-only cars have had.

      Granted, I am not an engi
    • Also bear in mind that Europeans used to use larger gallons than Americans, so be careful when you do mental conversions from litres to gallons in these discussions.
  • by BaCkBuRn ( 621588 ) * on Monday May 09, 2005 @09:37PM (#12483863) Homepage Journal
    And ./'ed within 5 seconds... They should switch to a premium unleaded/apache method :)
  • by Anonymous Coward
    Coincidence? I think not!
  • by duffbeer703 ( 177751 ) on Monday May 09, 2005 @09:39PM (#12483881)
    EPA estimates have never been really useful indicators of real-world results, nor were they intended to be.

    What they do provide is a car-to-car comparison that is consistent regardless of driving style, load, weather or other conditions. When you compare EPA mileage statistics, you're comparing apples to apples.

    Hybrids throw a monkeywrench into the mix, so we'll probably see an adjustment to the EPA methodology at some point.
  • by dreamer-of-rules ( 794070 ) on Monday May 09, 2005 @09:39PM (#12483885)
    I get about 8-10 mpg improvement by using the cruise control at any speed. I have a 2005 Honda Civic Hybrid and get about 38-41 mpg on average.
  • by sirket ( 60694 ) on Monday May 09, 2005 @09:40PM (#12483895)
    I have a 1978 British Mini (the old ones) and the gas mileage is anywhere between 50 and 60 mpg. Here we are almost 30 years later and we are getting- lower gas mileage?

    Granted the Mini does not weigh anything and lacks AC- still. The 1 liter engine kicking out 55HP (in my slightly modified engine) is more than adequate to move such a light vehicle. Add to that a suprisingly roomy interior (it will seat 4 people comfortably despite being only 10 feet long) and a car that will corner like a go kart and you have to ask yourself what the auto industry is thinking. Not to mention being able to park _anywhere_ :)

    We have materials today that Alec Issigonis (the guy who created the Mini back in the 50's) could only dream of- lighter, stronger and easier to shape- and yet cars today are far heavier. We get worse gas mileage- sure the cars are more powerful but then again they have to be. I realize some of this weight is the result of safety improvements and the like but it just feels like there has to be a middle ground.

  • GreenHybrid Server (Score:5, Informative)

    by Anonymous Coward on Monday May 09, 2005 @09:41PM (#12483904)
    Really sorry, guys. Slashdot sent me so many referrals the whole server went down! I won't be able to get ahold of my host for 2 hours, so please sit tight. Very sorry.

    Jason Siegel
  • by Anonymous Coward on Monday May 09, 2005 @09:42PM (#12483916)
    The amount of energy used by an average automobile over its lifetime (manufacture, operation, maintenance and disposal) that comes from the gasoline used to drive it is only a fraction (around 1/5 to 1/3) of the total.

    A hybrid does reduce the total energy consumption of a car over its lifetime compared to a conventional car, but not by all that much. It still takes all the same materials and manufacturing processes to build, and poses the same disposal problem once it wears out.

    The answer is a combination of fewer, longer-lasting, more-efficient cars, and less driving.
    • by metamatic ( 202216 ) on Monday May 09, 2005 @10:36PM (#12484383) Homepage Journal
      It still takes all the same materials and manufacturing processes to build, and poses the same disposal problem once it wears out.

      Well, at the risk of sounding like a Toyota ad, the Prius is built using 90% recyclable materials. For the soundproofing, they literally use shredded material from old cars. They use a tenth of the lead and a tenth of the PVC they were using in their cars in 1996. They even use plant-derived bioplastic for the floor mats.

      http://www.toyota.co.jp/en/news/03/0901a.html [toyota.co.jp]

  • VW Jetta wagon TDI (Score:4, Informative)

    by ender_wiggins ( 81600 ) on Monday May 09, 2005 @09:47PM (#12483966) Journal
    I get 42mpg in my daily drive, but not batteries to keep charged!
  • by tsangc ( 177574 ) on Monday May 09, 2005 @09:49PM (#12483983)
    ...is the visual display which tells you the target mileage given your current acceleration.

    I drove a 04 Prius for a few months and found that the display which tells you the fuel economy you're getting is very helpful. After about a day you realize that speeding up hills eats at your economy and braking appropriately helps too.

    If all cars had this feature, fuel economy would be increased. Regardless of the fact the Prius has a hybrid engine, low rolling resistance tires, etc, this simple display is a big psychological factor.

    Most people never realize their driving habits affect fuel economy because it only hits them every two weeks at the pump. By that time they never link it to how they brake or accelerate. By closing the feedback loop, you start to change your driving habits.

    Only expensive cars seem to have this feature, yet it's ridiculously simple to implement off a modern ECU. I wish they'd make it standard equipment and not a luxury feature.

  • by DocJohn ( 81319 ) on Monday May 09, 2005 @09:49PM (#12483986) Homepage
    The problem with hybrids isn't their short-term fuel efficiency (which we didn't need 150 folks to document, out of tens of thousands sold). The problems are:

    1. Premium cost over traditional fuel combustion engine (ranging from $3,000 - $5,000 over the same non-hybrid car).

    2. Long-term reliability and replacement costs of hybrid system (especially the batteries). 5 or 10 years from now, are these cars going to be proven as reliable as their traditional combustion-engine brethern? Or are they going to be visiting the shop more often to fix issues in their hybrid systems, replace their batteries (which do have a pre-determined lifetime), or whatever??

    The answers will come in time, but not from the data of 150 measly vehicles.

    PS - The dork who compared a 40-year old car to a modern vehicle just doesn't get it. Modern vehicles meet modern safety standards, including such luxuries as airbags, enhanced structures that help prevent serious bodily injuries, and a little more leg room. Yes, if I built a go-cart, I could probably also get 50-60 MPG. But I wouldn't be stupid enough to drive it on I-95.

    • Reliability (Score:4, Interesting)

      by metamatic ( 202216 ) on Monday May 09, 2005 @10:44PM (#12484444) Homepage Journal
      I think you have a point about reliability for the Ford... but given Toyota's reliability reputation, and the Consumer Reports rating which put Prius #1 in customer satisfaction, I think the Prius is a pretty safe bet.

      Toyota gives the batteries a 10 year warranty. The gas engine is the same as the engine in a Corolla, just adjusted to run on a different combustion cycle. There's no gearbox, so that leaves the transaxle and computer to worry about... Personally, I'll take that bet.
  • Is it just me (Score:3, Interesting)

    by ashpool7 ( 18172 ) on Monday May 09, 2005 @09:51PM (#12484014) Homepage Journal
    or are those numbers pretty piss-poor for hybrids? I remember when the Insight was pimped as having 70mpg and the Prius 60. Nobody comes close to those figures now. 30 mpg for a V6 Accord? The normal Accord gets only 7 mpg less (ajusted from vendor inflation [fueleconomy.gov]. Hybrid:37 Normal:30). The variance in the Escape is less than that.

    How can these cars be touted as environmentally friendly when you could easily increase your gas mileage by driving a 4-cylinder instead. That way, you get the gas savings and you aren't throwing away a huge battery full of toxic waste when you're done.

    Calling the Ford, Lexus, and Honda Accord "environmentally friendly" hybrids is disingenuous. They aren't helping the gas problem whatsoever.
    • by metamatic ( 202216 ) on Monday May 09, 2005 @10:48PM (#12484468) Homepage Journal
      How can these cars be touted as environmentally friendly when you could easily increase your gas mileage by driving a 4-cylinder instead.

      Because "environmentally friendly" is not the same as "economical".

      The Prius sacrifices some efficiency in order to get lower emissions. Specifically, emissions less than a tenth of what's allowed by California's standards.

      It's also 90% recyclable, recycled materials are used in its construction.

  • Not impressed. (Score:4, Insightful)

    by crankyspice ( 63953 ) on Monday May 09, 2005 @09:53PM (#12484027)
    My Porsche 3L Porsche 968 (at 11 years and 91,000 miles old) gets 32+ MPG on the freeway, and mid-20s in city traffic. My BMW motorcycle gets over 70MPG. (Granted, those of you who don't live in SoCal probably can't motorcycle commute 49 weeks out of the year the way we can ;) I expected a lot more out of the Accord. (I don't expect anything from Ford, except maybe mechanical problems. ;)
  • I don't want luxury (Score:4, Interesting)

    by lheal ( 86013 ) <(moc.oohay) (ta) (9991laehl)> on Monday May 09, 2005 @09:57PM (#12484062) Journal
    I commute 65 miles each way, 5 days a week. It's all pancake-flat Illinois interstate. I'm too cheap to buy a new car at new car prices. I'd like to buy a hybrid or all-electric vehicle with:
    • Mechanical windows and locks
    • Mechanical ventilation (AC not required)
    • A heater
    • LED lighting
    • Burlap interior
    • No radio

    Cheap, basic transportation. I'll buy my own seat covers, floor mats, stereo, etc.

    I hate the inflated prices car makers charge, getting people to buy on credit what they can't really afford to own. I guess I'm the only one, though.

    • by xtal ( 49134 ) on Tuesday May 10, 2005 @12:17AM (#12485103)
      Here's how to build a cheap, 50mpg+ car.

      Hybrid benefits are overrated because of the weight of the vehicles. This decreases much of the benefit.

      Take a 1992 honda civic chassis. Look for one of the efficient models (Vx, others). You want a 5spd. They are very easy to work on, and very common. Engine reliabilty is great.

      These cars were commonly available with no power steering, and no AC. Power locks and windows? Ha!

      Strip the car bare. Gut it. Install some lightweight racing seats. You just saved a lot of weight. And gained a lot of cargo room!

      Have the engine reworked. Lots of manuals for this; it can be done in a weekend, with a weekend of preparation. You'll need to clean all the fuel filters, injectors, and install all new ignition components.

      Install a wideband o2 sensor with a car monitor. Consider an EGT meter as well. This will let you track your mixture inside the car to see if you're running rich and/or overheating your exhaust valves.

      Install a VAFC, a small computer that tweaks the fuel settings. Most of the time these are used for power, but you're going to use it to dial out as much gas as you can without running too lean.

      Voila. Plus it's cheap to insure.
  • by Leomania ( 137289 ) on Monday May 09, 2005 @10:03PM (#12484115) Homepage
    Hybrid cars seem like the answer to rising gas prices, increased pollution and growing dependence on foreign oil

    Although I am the proud owner of a new Toyota Prius, I can unoquivically say that hybrid cars are not the answer; they are a stop-gap measure that may extend the period of time that oil is a primary fuel on the planet Earth. However, they are too little too late; I have the income to allow me to "do the right thing" but really, I should either move closer to where I work or take public transportation to really do the right thing. I'm not going to do that, and my neighbors are going to bitch about how much it costs to drive their SUVs but they don't look like they're selling them anytime soon.

    So who cares what the mileage figures are? The hybrids are far better than the other cars on the road, but they won't amount to any appreciable percentage of the cars on the road until gasoline is priced high enough to force it, or the government mandates it. Neither is going to happen, so unless there's some miraculous breakthrough that provides a cheap source of hydrogen pretty damned soon, it's all moot.

    Yeah, I'm kinda pessimistic about energy usage in the U.S. We're kinda like the guy who jumped off the really tall building saying, "Nothing will happen!" who could be heard saying as he fell past each floor "So far, so good!"

    Still, I bought a Prius to support the company that made the R&D investment to give us a stop-gap solution, even if we're not moving to a viable alternate energy source with the urgency we should. Meaning, I don't know if my partial gesture will matter, but it's better than driving the car it replaced at half the mileage.

    - Leo
    • by TooMuchToDo ( 882796 ) on Monday May 09, 2005 @10:33PM (#12484367)

      Toyota is doing what GM and Ford couldn't do. It's letting it's customers help fund it's R&D related to the transition from gas to electric.

      Future cars are going to be all electric. That's all there is too it. Why? Simplicity. It takes a great deal of effort to design a mechanical structure that can transmit anywhere from 200-600 bhp from the front of the car to the back. You lose efficiency on the drive shaft, at the transmission, etc.

      The end game of cars is going to be where the motors are built into the wheels. The power plant is interchangeable (and inconsequential). When you brake, all four wheels will capture the energy into some sort of temporary energy storage device.

      Toyota knows this. The Prius is subsidized R&D. Personally, I think it's a fabulous idea.
      • by Moraelin ( 679338 ) on Tuesday May 10, 2005 @06:46AM (#12486720) Journal
        1. Electric engines and direct coupling are good and fine, but the problem nowadays is that, basically, batteries suck. They don't come anywhere _near_ the energy density of gasoline or diesel.

        Which doesn't just limit your range in an all-electric car, but also makes the whole car heavier. It means you actually need more energy to move at the same speed and over the same distance.

        Hybrids acknowledge that reality. The electricity in a hybrid ultimately comes from gasoline too, and is only used so often.

        I.e., expect to see hybrids instead of all-electric cars for a long time.

        2. The whole "waah, but oil is going to end" premise is bogus anyway.

        Yes, fossil reserves will eventually end. But here's the fun part: we already know how to produce synthetic oil. We've known it for a long time. And not just theoretically: Germany's WW2 tank warfare was _based_ on synthetised fuel. It wasn't cheap, but it did keep the panzers rolling nevertheless.

        That's really the only thing that keeps us using fossil fuels right now: it's cheaper than making synthetic fuel. If fossil reserves start running low, whoppee, we'll just start making synthetic fuel. And all those gasoline or diesel cars will keep running just the same.

        In fact, doing that is probably a more economical and viable way to store energy than a ton of batteries in a car.
  • by rush22 ( 772737 ) on Monday May 09, 2005 @10:08PM (#12484158)
    15 years of innovation and a completely new engine design, and we end up with a somewhat safer version of the Geo Metro (40% heavier... and with half the cargo space.)

    1990 Geo Metro XFI Specs [consumerguide.com] & Mileage [fueleconomy.gov]

    Weight: 1694 lbs
    Cargo Volume: 31.4 cu. ft.
    Front leg room (Max): 42.5 in.
    Rear leg room (Min): 32.6 in.
    Crash Test: Driver ***, Passenger ****

    City: 53 MPG
    Highway: 58 MPG
    Combined: 55 MPG

    2005 Toyota Prius Specs [consumerguide.com] & Mileage [fueleconomy.gov]

    Weight: 2890 lbs
    Cargo Volume: 16.1 cu. ft.
    Front leg Room (Max): 41.9 in.
    Rear leg Room (Min): 38.6 in.
    Crash Test: Driver *****, Passenger ****

    City: 60 MPG
    Highway: 51 MPG
    Combined: 55 MPG
    • Wow, 40% heavier and still gets the same mileage! Any other person would say this was a major improvement.

      AND, the Prius is a 5 passenger car with AT-PZEV emissions. One lawn mower session puts out more emissions than a Prius after driving 500 miles. Think about the summation of health costs saved with cleaner air, besides just oil.

      And take a look at this picture of your 31.4 cu.ft space Metro [consumerguide.com]. I don't see a huge cargo space behind the back seats, so it must come from folding down the seats.

      If you ge
  • Jetti TDI (Score:3, Informative)

    by iamcadaver ( 104579 ) * on Tuesday May 10, 2005 @08:10AM (#12487062)
    I have to point out that AT WORST my mileage on a '98 Jetta TDI (read: diesel) has been 46 mpg.

    The average is a steady 48 mpg.

    I was an avid follower of hybrids until an article on /. noted that the VW TDI's were getting >= miles per gallon than the hybrids. So, this post is just me giving back.

This process can check if this value is zero, and if it is, it does something child-like. -- Forbes Burkowski, CS 454, University of Washington