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Hydroelectric power power plant

  1. Nov 5, 2014 #1
    Sir, why for a hydroelectric power power plant, the minimum height is 34 meter.? Please explain
  2. jcsd
  3. Nov 6, 2014 #2


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    Gold Member

    I was unaware of that requirement, unless you mean for a specific capacity of generation. More drop means more kinetic energy impinging the turbines or paddle wheel or whatever. I've seen farm units that work from only 3 metres or less, but they don't produce much.
  4. Nov 7, 2014 #3
    I would have to agree with the previous post. The higher the water is dropped from, then the more time the water will have to be affected by gravitational acceleration. Due to this principle, the water will be faster as it strikes the turbine if dropped from a greater height. That is why we see dams as very tall, very large structures.
  5. Nov 7, 2014 #4


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    Staff: Mentor

    Minor caveat: most low-head hydroelectric plants use the potential energy directly, without converting it to kinetic energy first.

    Hoover dam = tall = kinetic energy (Pelton turbine)
    Three Gorges Dam = shorter = standard turbine.

    But the basic points still stand: no minimum head requirement and taller means more energy at the same flow.
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