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Hybrids in the News



  • explorerx4explorerx4 Central CTPosts: 9,444
    my sister has a prius. on the 500 mile highway trip just short of 50 mpg is normal. the car is usually loaded down too, so that is impressive.
    drving locally here in ct on in a cold late november the computer read 35 mpg average. driving up my street, the instantaneous mileage dropped to 8, until my bil shut off the display.
    i just don't think the mileage estimates are a slam dunk.
  • tpetpe Posts: 2,342
    I've never stated that hybrids won't get better mileage than other vehicles in their class. They definitely will.

    Have you done any research on how the EPA's new testing methods will affect hybrids? If you have then you would realize it will have a bigger impact on hybrid mileage ratings than it will on other vehicles. The new results will still show that hybrids provide better fuel economy just not at the level previously indicated. I'm fine with that. It will be more accurate and it will be the new benchmark.
  • tpetpe Posts: 2,342
    If you do a web search on "prius mileage" you will find that is pretty much the consensus. The rated highway mileage is fairly accurate. The city mileage is totally out of whack. The Prius's city mileage rating of 60 doesn't come close to reality. That will be addressed with the new EPA rating method. The Prius will then have a city rating of around 42 mpg. Still excellent but no where near this ridiculous 60 mpg figure. Average mileage is generally computed by taking 55% hwy mileage and 45% city mileage. This significant reduction in the city mileage will result in the Prius EPA rating ending in the mid 40s, where it belongs.
  • backybacky Twin CitiesPosts: 18,622
    Overall: Simpler, cheaper hybrid is a dandy idea, but the aging Vue isn't the best showplace. x.htm
  • tpetpe Posts: 2,342
    Below is a description of how the govt. and Consumer Reports determine a vehicle's fuel efficiency. I'm not sure why anyone would refer to CR's test results as anectdotal unless they just don't understand the meaning of that word.

    Details of the tests

    The vehicles

    Our tests. We anonymously buy production models at retail. All vehicles are preconditioned for about 2,000 miles. Tire pressures are set to manufacturer specifications.

    Government tests. Automakers are allowed to use hand-built prototypes.

    Driving conditions

    Our tests. All testing is done outdoors year-round, never during precipitation, with all results adjusted to a standard temperature of 60° F. For gasoline-electric hybrids, we start our tests with the battery at the charge level you normally find--about half. A calibrated fuel-flow meter is used to measure gas consumption.

    Government tests. EPA fuel-economy tests are done in a laboratory with the test vehicle's drive wheels resting on a dynamometer, which has a roller that allows the automobile to simulate driving while remaining stationary. Gasoline consumption is calculated based on the amount of carbon emitted from the vehicle's tailpipe, which the EPA says is more accurate than a fuel gauge.

    To test all-wheel-drive vehicles, automakers and the EPA remove the front prop shaft and adjust the inertia weight on the dynamometer to account for four-wheel-drive factors. To test hybrid fuel economy, the EPA method allows automakers to start with a fully charged battery.

    The EPA tests represent driving in southern California at 75° F on a road with no curves or grades, which is ideal for optimizing fuel economy.

    City mpg

    Our tests. These tests are stop-and-go city-driving simulations on our test track, which has a total of 18 stops and 4 minutes of total idle time. Top speed is 40 mph. Two different testers each drive three runs for a total of six 2-minute, 40-second trials on every test vehicle. Total test time is approximately 16 minutes.

    Government tests. The city test simulates stop-and-go city driving with 23 stops and includes 5 minutes and 35 seconds of total idle time. Top speed is 56 mph. A professional driver manipulates the gas and brake pedals to follow a prescribed schedule of acceleration and braking while monitoring progress on a real-time graph on a computer display. The test runs for 31 minutes.

    Highway mpg

    Our tests. The highway tests are run on a specific section of state Route 2 near our test facility in central Connecticut. Two testers make eight 5-mile runs at a constant 65 mph. The tests are run in both directions to limit the effects of wind and grade differences. Each run is timed and limited to 4 minutes, 38 seconds. Total test time is approximately 37 minutes.

    Government tests. These tests simulate free-flow rural and interstate-highway driving. The professional driver starts from zero, maintains a fairly smooth speed averaging 48 mph, then slows to zero over a prescribed 12-minute, 30-second schedule. While under way, speeds range from 30 to 60 mph.

    Other differences

    Our tests. We run a test that the government doesn’t require: a one-day trip test, which reflects a mixed driving cycle. Five different engineers drive back-to-back on the same day over a 31-mile route that includes 26 percent (8.2 miles) freeway, 11 percent (3.6 miles) highway, and 63 percent (19.2 miles) stop-and-go driving conditions.

    Government tests. Automakers conduct the fuel-economy tests and submit their results to the EPA for certification. The EPA retests 10 to 15 percent of the vehicles. The EPA says that less than 10 percent of the retests are significantly different than the original automaker tests.

    The math

    Our tests. Trials within each type of test are averaged and corrected for ambient temperature to produce our published city and highway mpg ratings and our one-day trip rating. Our published overall mpg estimate is calculated as an equally weighted harmonic average of the city, highway, and one-day-trip results.

    Government tests. The raw test results are adjusted downward by 10 percent for city mpg and 22 percent for highway mpg, and a combined mpg is calculated as a weighted harmonic average using the two in a 55/45 city/highway ratio. Those adjusted figures are the ones published on vehicle fuel-economy stickers.
  • john500john500 Posts: 409
    Good post. A large concern with the government (or EPA) test is the absence of a air drag factor and the unreasonable speed used for the highway test. The CR test is probably very close to real world mpg. Everything is there (engine break in, reasonable speeds, tests are replicated several times). I think I might get one of those in-line fuel meters for my car to negate the "extrapolation" effect from estimating the amount of gasoline consumed by volume replacement (ie refilling to full).
  • tpetpe Posts: 2,342
    I've driven several vehicles that have been tested by CR. I find their mileage ratings to be pretty accurate. In my cars I get within 1-2 mpg of their figures. They do achieve the EPA's hwy rating of 50 mpg for the Prius. It's the 60 mpg city mileage that needs to be completely dismissed. In fact I've read that Toyota ends up fielding a lot of complaints from Prius buyers that feel they've been somewhat duped. Toyota is put in a tough spot. These exagerated ratings help them sell cars but result in dissapointed customers. My guess is that a rating of 40/50 city/hwy would be more accurate. Still best in its class.
  • larsblarsb Posts: 8,204
    18 September 2006 - General Motors says it will have a fuel-cell vehicle in production by 2015 at the latest.
  • kdhspyderkdhspyder Posts: 7,160
    Have you done any research on how the EPA's new testing methods will affect hybrids? If you have then you would realize it will have a bigger impact on hybrid mileage ratings than it will on other vehicles

    Yes I have done research on what effect the new testing parameters might have on the EPA ratings. Ss reported in several places since earlier this year the ratings on the vehicles and on the window stickers might change 15-30% mainly in reducing the City values to more 'realistic' numbers.

    Note what Toyota has done with the new TCH as compared to the Prius and HH. For the TCH the City/Highway values are 40/38 or about an 8% difference between the two.

    For both the Prius and the HH the values are 60/51 and 32/27 respectively. Each difference here is 20% between the two. The city being very very optimistic. Attainable but optimistic.

    Despite any ratings changes however nothing will change in the vehicles themselves so the GreenHybrid values will remain unchanged. just the stickers will change.
  • terry92270terry92270 Posts: 1,247
    I agree with you, kdhspyder.

    The fact is, nothing printed on a label, or passed out by the Government, can stop the glowing word-of-mouth from actual owners about how much they are $aving with every fill-up.

    Less gasoline consumed equals less pollution in the air, and more conservation of our resources. Alone, one car or one thousand cannot make much difference. Tens of thousands can. It's all one-step-at-a-time.... ;)
  • kdhspyderkdhspyder Posts: 7,160
    Agree that this correctly describes the differences between the two tests. There is one very clear omission which is not brought up by CR.... 'warm up' time.

    In the EPA tests the vehicles are first warmed to operating temperatures at which time the testing is done. From CR's description they start up the vehicles and go into the testing at both the City and Highway methods. This is realistic of what for many might be a typical trip of 5-15 min. However it is not realistic for a driver of a longer commute or one in heavy traffic for an hour or two for say 10-20 miles.

    This doesn't affect only hybrids, all vehicles have this 'warm up' penalty. This may be why CR's Fuel Economy values are so consistently low for every vehicle in relation to the admittedly artificial EPA tests. Essentially in CR's system all vehicles are tested in the least efficient criteria while in the EPA test it might be stated that they are tested in the most efficient method.

    Please note from an earlier post that I mentioned that there are several negative factors that might reduce fuel economy not only in the hybrids but any vehicle.
    Other factors may enter into the equation which positively or negatively effect the result. 6 are able to be quantified:
    Cold weather : -10%
    Rainstorms : -15%
    Severe winds : -15% to + 5%
    vehicle loading : -5% to -15%
    Highspeed driving over 70 mph : -10%
    Short trips : -20% ( this is the real killer since the warmup period is the entire trip )

    Short trips in any vehicle will normally reduce fuel economy by 20% or more depending on other factors. Driving at 65 iso 48-55 will deteriorate it additionally.

    Good data though in your post.
  • kdhspyderkdhspyder Posts: 7,160
    I've driven several vehicles that have been tested by CR. I find their mileage ratings to be pretty accurate. In my cars I get within 1-2 mpg of their figures. They do achieve the EPA's hwy rating of 50 mpg for the Prius. It's the 60 mpg city mileage that needs to be completely dismissed. In fact I've read that Toyota ends up fielding a lot of complaints from Prius buyers that feel they've been somewhat duped. Toyota is put in a tough spot. These exagerated ratings help them sell cars but result in dissapointed customers.

    Since my own driving for the last 25 years has been more of the marathon type vs sprint type I've found the CR values of the 4c Camry's and the Prius to be too low. All the Camry's consistently achieved 31 mpg on an annual basis while the Prius is currently at 48.5 mpg. But my shortest trips are normally 1 hour.

    I agree that the 60 mpg figure is both a selling point and a point of contention. If an owner has the hybrid system explained in detail and understands how the figures come to be made then it's not an issue normally. If a buyer shows up and drives off with no explanation of how to use the vehicle much less maximize the fuel economy it's not a wonder that many are disappointed. It's just a matter of education.

    Again the EPA values are just the result of physcial tests with specific parameters. If one can drive to these 'artificial' criteria then one will achieve the EPA values. Some drivers can do this all day long because their personal situation allows them to do so. To dismiss this out-of-hand is not any more valid than saying that all drivers should get 60 mpg in City.

    Yes some drivers feel 'duped' - mainly because they weren't educated enough about the vehicle - whereas some are ecstatic to be able to achieve 55 mpg annually and higher.
  • terry92270terry92270 Posts: 1,247
    From reading these forums, no doubt "some" always feel duped or cheated, for even the slightest of things...

    Most of us would be happy as hell getting 10 MPG over what we are, and that assuredly, by anyone's measure, the TCH will achieve, with no loss of performance. ;)
  • tpetpe Posts: 2,342
    I think that CR's city figures represent stop and go conditions that may exceed what some people consider typical city driving. This results in them arriving at very conservative city numbers. However their highway figures aren't all that far off what the EPA puts out. CR also provides a mileage based on a 150 mile trip. For the Prius it was 48 mpg. For the 4 cyl Camry they got 29 mpg. That may be closer to the type of driving that you do. I'm still very skeptical that anyone is consisitently able to achieve 60 mpg city mileage in the Prius.
  • larsblarsb Posts: 8,204
    States buying more hybrids than gassers

    For the first time, the state's public agencies bought more hybrid cars than standard gasoline-powered cars in the past 2006 model year, according to the state Department of General Administration.

    In the 2006 model year, the state bought 222 Toyota Prius models compared with 218 gas-powered vehicles through state contracts managed by the general administration department. State agencies also bought 206 Ford Escape hybrids and 390 vehicles that can run on gasoline and ethanol.
  • gagricegagrice San DiegoPosts: 28,680
    I agree that it is good. We will get some consistent data on the longevity of the hybrid technologies. If they become a maintenance nightmare you can bet they will not purchase as many the next go around.
  • terry92270terry92270 Posts: 1,247
    The second paragraph is talking about California, I believe.

    They have extensive knowledge of alternative-fueled and mix-fueled cars, as they have been buying them for almost two decades now, since Ronald Reagan, followed by Jerry Brown, first initiated the experimental process.....and they have not found any maintenance "nightmares".

    So although for many States, this is a new practice, for California it is the culmination of a twenty year practice. ;)
  • larsblarsb Posts: 8,204
    Let's hope not.

    The true test will be the next six months when a LOT of things start going BAD for us hybrid advocates:

    1. The tax credit gets smaller and eventually gets really small.
    2. Gas prices stay low, in the $2.25 range.
    3. More hybrid vehicles hit the market, meaning more choices BUT not much tax incentive to move them.

    If people keep snatching up hybrids, then all is well. If not, then it will indicate a "saturation point."

    Problem is though, there are 12 more hybrid models coming to the USA by the end of the 2008 model year. Carmakers are going to eat a lot of metal if no one wants to buy those new cars.
  • terry92270terry92270 Posts: 1,247
    Gloom and Doom, Gloom and Doom! :P

    All of the credits will be renewed and supplemented by more State credits, already in the legislative pipeline in dozens of States! :)

    Please do not say there is no "guarantee". What are you guaranteed about anything?
This discussion has been closed.