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  • It’s been estimated

    that making each unit of petrol requires an input of 1.4 units of oil and

    other primary fuels (Treloar et al., 2004).
    • tonycurzonprice
      Tonycurzonprice on 2009-01-31
      Just to be clear: this means that if I have 2.4 units of "primary fuels" (whatever they are), then I can expect to get 1 unit of petrol out. Quetion -- those 1.4 units ... are they _consumed_ in the refinery process, or are they partly bye-products that can be used for other things?
    • djcmackay
      Djcmackay on 2009-08-24
      No, not 2.4 units, 1.4 units!
  • The total amount of car travel in the UK is 686 billion

    passenger-km per year, which corresponds to an “average distance travelled

    by car per British person” of 30 km per day.
    • tonycurzonprice
      Tonycurzonprice on 2009-01-31
      I tried to do a quick compare with France. This very attractive site:
      http://sansvoiture.free.fr/index.php?menu=textes&sousmenu=autodecroissance
      claims 14,000 km per car per year average. At one person per car, driving 250 days per year, we get to 56km per day on average.

      I was hoping to say: "High Speed Trains were planned for in 1974 in France; more than 30 years later, their logic becomes clear..." even if this is true, the averages here don't scream it out ...
  • I want to estimate

    the energy consumed by someone who chooses to drive
    • casaba
      Casaba on 2009-08-21
      I like the idea here; I agree that 'averages' are abused. Somehow similar to everyone believing that they have above average driving skills. However it seems that in using a km/person/day value 66% greater than the average, the calculations later regarding necessary energy production are all suspect (because the total production is simply averaged to a kwh/person/day value). Considering how large a portion of our energy is used by cars, this choice is significant.

Public Stiky Notes

  • casaba
    Ché Duro on 2009-08-13
    I like the idea here; I agree that 'averages' are abused. Somehow similar to everyone believing that they have above average driving skills. However it seems that in using a km/person/day value 66% greater than the average, the calculations later regarding necessary energy production are all suspect (because the total production is simply averaged to a kwh/person/day value). Considering how large a portion of our energy is used by cars, this choice is significant.

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