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Fast and slow speed of Fan in hot weather?

  1. Jun 16, 2010 #1
    Hi all, I am wondering that we should choose fast or slow function of electric Fan in hot weather, which function will spend much more of energy?, can someone give me an explanation :D Forgive me if the questions is silly
    Last edited: Jun 16, 2010
  2. jcsd
  3. Jun 16, 2010 #2

    Movement of air it gives the sensation of coolness.
    Hurry evaporation, which consumes energy, so it cools.
    (When something is hot, you blow over it.:smile:)
  4. Jun 16, 2010 #3
    I received an answer from another forum that:
    "Regarding such as windmills are the way we think of but here it is another different. about Windmills, you eat less (less wind-> less energy), the less electricity it, eat it (much wind -> more energy), it granted more power. It is your case fans for its abundance (plants with a capacity of xxxx folding times) and eat it how much it took, slow fan on the fan then consume less but consumed on multiple inductors, fans back quickly on the fans consume more but less consumption in the inductors"...

  5. Jun 16, 2010 #4


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    The higher setting will use more energy. Energy defined as the integral of work. When the fan is at a higher setting, it's performing more work on the fluid flow, ergo more energy.
  6. Jun 16, 2010 #5


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    What exactly is your question?

    Which setting will expend more energy? Definitely the faster setting.

    Or are you asking a different question, such as: which setting is better to keep you cool? A lower setting that creates less waste heat?
  7. Jun 16, 2010 #6
    yeah, that's my question, 'cause i saw an argument from other guys that someone says fast or slow function of fan they expend energy equally, someone says fast function expends much more energy, and they illsutrate by complex formulars of input and output energy on how it was transformed in different function of speed :confused:
  8. Jun 16, 2010 #7


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    Staff: Mentor

    On the faster setting, the fan expends more energy.
  9. Jun 16, 2010 #8


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    Tell them that's really awesome. If turning up dial of a fan does not use any more energy, then they could scale this up thousands of times to have the fan go hundreds of miles per hour (without using any more energy), then put wind turbines in front of their fan, and solve the energy crisis. :rolleyes:
  10. Jun 17, 2010 #9
    Hi, thanks a lot, now it's very clearly, and very exciting answer, i'll quote your illustration and send them now ;)
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