• Question: How do windmills produce energy

    Asked by 433enek48 to Emma, Karla, Shane, Stephen, Yang on 13 Nov 2017.
    • Photo: Karla Dussan

      Karla Dussan answered on 13 Nov 2017:

      Old windmills in the past used captured the energy of the wind with the propellers, whose movement was transmitted to a mill that grind cereals and other foods…
      Windmills today, or wind turbines, work on the same principle. However, the energy of movement of the propellers is converted into the electrical energy using a generator: the movement of a coil inside a magnetic field produces an electrical current that can be stored or transported into the electrical grid to be used by anyone of use đŸ™‚ You can have a look at the fundamental principle of the electric generator here —>

    • Photo: Stephen Rhatigan

      Stephen Rhatigan answered on 13 Nov 2017:

      This is a great question. I’ll focus on how wind turbines convert the kinetic (moving) energy of the wind into electricity.
      The blades are connected to a shaft which in turn is connected to a generator.
      The wind causes the blades to move and the shaft rotates. This motion causes the rotor of the generator to rotate and this produces electricity.
      To understand how the generator works you need to know a little bit about electricity and magnetism.
      Electricity and magnetism are linked: a moving electric field produces a magnetic field and a moving magnetic field produces an electric field.
      An example of a moving electric field is a current flowing through a wire. If you imagine holding the wire in your right hand with your thumb pointing in the direction of the current, the magnetic field will wrap around the wire in the same direction as you fingers.
      The rotor of the generator has two magnets surrounded by loops of copper wire. As the magnets move over each other (moving magnetic field) they produce an electric field and this causes (induces) current to flow in the copper wire in a process called induction.
      So to sum up:
      Wind moves the blades —> the shaft rotates —> magnets in the generator move producing an electric field —> an electric current is induced in the copper wire.

    • Photo: Emma Hanley

      Emma Hanley answered on 13 Nov 2017:

      As Karla and Stephen have it covered I will just add that wind energy is very important to Ireland’s energy system and in 2014, 17.7% of Irish electricity came from wind