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As I approach 1K miles, I have some observations. Are these typical?

Discussion in 'Gen 3 Prius Fuel Economy' started by dhs, Jul 16, 2009.

  1. dhs

    dhs New Member

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    III
    First, it is easy to get 50 MPG in this car, you have to work to get 70.

    Second, while the engine in warming up, gas mileage stinks.

    Third, it is really hard to break 55 mpg in Washington DC rush hour traffic.

    Fourth, Stop signs at the bottom of hills are killers.


    In my commute to work, 14 miles on side streets, I get between 65 and 70, largely dependent on *one* traffic light at the bottom of a hill on Lee Highway in Falls Church, VA. I usually leave for work between 6:15 and 6:30 AM, so traffic is not bad. I do not have to work hard to get those numbers....All I do is glide down all hills, and pulse up the hills.

    Going home (usually 4:30 PM), traffic is heavier, and my mileage is about 50-55. I think the main thing is I can not glide down the hills.

    On a road trip, 55 MPG was easy without pulse and glide, but just going with traffic at 65 MPH.

    Now a few questions:

    I have been thinking that while the ICE is warming up, it may be advisable to charge the battery through use of 'B'. Is this true?

    Am I better off accelerating hard (flooring it) for 15 seconds than gliding, or keeping the eco light on and have the ICE run for much longer?

    Thanks!
     
  2. patsparks

    patsparks An Aussie perspective

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    If you don't have any hills so long and steep that your battery is full at the bottom, or rather over full, don't ever use B. Braking gives more regen that B. B spins the petrol engine without injecting fuel, to burn off excess energy, braking lightly gives higher regen.
    Of course as you have said, the most efficient way to drive is without touching the brakes if you can get away with it.
     
  3. TonyPSchaefer

    TonyPSchaefer Your Friendly Moderator
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    On the observations: They are all true. They made me laugh because I've lived them all - except the DC part.

    mode is primarily for going downhill. Given the dramatic mountains of our nation's capital (sarcasm) I don't think you need . You're better off just driving and charging the battery normally.

    There is a whole school of thought on the art of acceleration. I believe the prevailing thought is that a "brisk" acceleration of approximately 75% depression is best until you get up to cruising speed and then laying off and coasting/pulsing/gliding from that point on.

    I hope I got all the correct. I'm sure others will correct me where I'm wrong.
     
  4. Argyle

    Argyle New Member

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    Acceleration seems to bring out a lot of opinions.
    I am not sure if I am doing this right, but I keep an eye on the HSI and when taking off from a stop or speeding up, I try to keep it in the top end of the Eco zone and when I get up to my desired speed I let off and press slightly on the pedal to keep the HSI at the bottom end of the Eco zone.
    When I see a stop light in the distance, I let off the accelerator and let it go into the regen area until I need to brake.

    I have heard you you should just punch it and go. I have heard you should stay out of the power zone. I know you need to get the ICE going and try not to drain the battery.

    I try to stay at the speed limit on expressways. (55 for the most part in this area.)

    In other words, I drive like a nervous cardiac patient. If I cooked like I drive I would be feasting on egg white omlettes with white toast.