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Factors affecting MPG

Discussion in 'Gen 2 Prius Fuel Economy' started by KentD8888, Oct 15, 2008.

  1. Raider

    Raider New Member

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    Are there any calculations I can use to explain to non-Prius drivers, the energy used driving up an incline, cannot be re-generated driving down the same incline?

    I generally drive slower and take the longer route to avoid hills, to maintain my fuel tank MPG but I still cannot get the other passengers out of the house early enough that we are always not rushed to get from place to place... (I've already adjusted clocks to look like we are running late but they already figured out the time offset.)
     
  2. Fibb222

    Fibb222 New Member

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    Thanks for that.
     
  3. gunguy05

    gunguy05 Junior Member

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    I have never driven w/ my lights on in the daytime.... y'all act like it is an unspoke law. My thought is that if everyone if forced to do it... as was mentioned in Canada, then what is the point. No one will stand out b/c we will all be the same.
     
  4. Fibb222

    Fibb222 New Member

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    see post 20
     
  5. Celtic Blue

    Celtic Blue New Member

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    It's a bunch of hooey from some safety nazi's. Same folks will try to sell you security lights that also do nothing but waste energy running year round. In reduced viz conditions I strongly encourage switching on the lights to improve visibility, but for good weather, normal daylight? It's just a waste of energy.

    In broad daylight to you see other cars first or their lights? I see the cars, not the lights. I've started looking for the lights, and so far in good weather I see the lights second, after seeing the car. Reduced light is another matter. Hence, the reason smart drivers turn on their lights in appropriate conditions.
     
  6. Fibb222

    Fibb222 New Member

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    You are entrenched in your position, despite reading in one study that DRLs provided
    I guess that's the Stephen Colbert approach to seeing the world. Going with your gut, not with your head.

    We have a lot of that in North America.
     
  7. Codyroo

    Codyroo Senior Member

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    Did you ever stop to think that you both might be right? In the study that was quoted (showing an 11% decrease in frontal accidents) did it list out the times of day that the benefit was seen? You are making an assumption that if was evenly distributed throughout the day. Perhaps it was skewed towards Dawn and Dusk with a minima in the middle of the day. If that is the case, both you and Shawn are now argueing the same point.
     
  8. Codyroo

    Codyroo Senior Member

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    You are taking the wrong approach. Take the airline approach (with a focus on ontime departures). Let them know that the car is leaving at a certain time, and then leave at that time, regardless of who's ready. You'll only need to do that a couple of times (for the stupidly stubborn) before they get the message. But we are too kind in this society....
     
  9. Celtic Blue

    Celtic Blue New Member

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    Codyroo caught the jist of what I was saying. The sheeple didn't, probably because they are "going with their gut and not their heads." :rolleyes:

    As it is, there is a finite MPG penalty for running your headlights during the day. That, MPG, is what the thread is about. Since I had calculated the penalty I listed it here. Some sheeple claiming it is unsafe to drive without headlights in broad daylight does nothing to advance the cause of reasoned analysis.
     
  10. Fibb222

    Fibb222 New Member

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    The thinking man doesn't just rely on his own 5 senses. If a study is any good, it's better than any one man's perceptions and opinion. Especially if said man can't perceive an 11% reduction in collisions as significant.
     
  11. Celtic Blue

    Celtic Blue New Member

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    First of all, it is unlikely to be significant. There are many other factors that could swamp it and would be a very difficult study to create and filter for. Second, a thinking man uses a bit of judgement. Third, a thinking man doesn't ignore his senses or judgement because of a questionable study. At any rate, time of day and weather effects are important as I noted. Apparently you are to dim (pun intended) to notice that and would rather continue with the condescending crap.

    I object to the simplistic and antagonistic nonsense about it being unsafe to drive in broad daylight without your lights.
     
  12. Fibb222

    Fibb222 New Member

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    Not unsafe, less safe.
     
  13. Fibb222

    Fibb222 New Member

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    From Daytime running lamp - Wikipedia, the free encyclopedia

    Let data be the ultimate arbiter.
     
  14. Celtic Blue

    Celtic Blue New Member

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    Fibb222,

    There is still no accounting for the very conditions Codyroo and I have emphasized. Screen that out and the numbers are going to fall into the range of noise. (And you misrepresented the data with the 11% figure. It applies only to multiple car collisions and only during the day which amplifies the value greatly. But hey, I expect misrepresentation from sheeple going by their gut and not their heads.)

    But hey, have fun burning the extra fuel as a security blanket!
     
  15. mrblaise

    mrblaise Go Lakers!!

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    Is "sheeple" the word of the week? jeeesh!

     
  16. Fibb222

    Fibb222 New Member

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    This is simple. It boils down to you being wrong about DRLs being useless. The fact that you can disregard/ignore this statement - the concept of the daytime running light has repeatedly been scientifically shown to have safety value -shows everyone that you're using your gut and not your brain.

    You don't think that the studies backing up that statement were done properly? You don't know jack about that. But as long as you've never (consciously) noticed headlights during the day, you're content to believe that all the DRL studies in the world are immediately suspect.

    And of course the 11% figure involves multiple (2+) car collisions during the day. That's when DRLs are in use. What did you expect the figure was for? Single car Accidents at night?

    And I'm sure your 2% mpg hit value is bang on! :boxing:
     
  17. Celtic Blue

    Celtic Blue New Member

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    Just thought I would post with random font sizes and colors, so that my post could look MORE LIKE YOURS!

    What a handjob.
     
  18. Fibb222

    Fibb222 New Member

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    You forgot to add a stupid little smiley dude.:D
     
  19. Codyroo

    Codyroo Senior Member

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    But, in the studies you've read, have they listed the data by time of day? I'm assuming that the numbers you are quoting are from some type of table summarizing the overall effectiveness (and typically, it's all the reader wants to see). But, if this is going to be debated, then it would be valuable to know if the effect is skewed towards certain parts of the day versus others.

    BTW, Shawn did concede that point that DRL's likely would have increased effect around dawn and dusk. He's contending, though, that the middle of the day may not be necessary. But it is simpler to require DRL's all the time than to require them at Dawn and dusk +/- 1 hour
     
  20. Rokeby

    Rokeby Member

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    Mods, is there any way that this thread can be split into two:
    * In the Fuel Economy forum; Factors affecting MPG, and
    * in the Main or Technical Discussion forums: something like, Daytime
    Running Lights; Effective or Not?

    The latter idea started back around post # 13, but by post 25 came to
    dominate and stifle any further discussion on the MPG question.

    At this point, neither discussion is well served by their being intermingled.