Harnessing wind energy

Year level: Middle Primary/Lower Secondary Learning outcome Students explore the design of wind-powered generators and then design, build and test their own windmill. Preparation • Access to computers and The Le@rning Federation digital content • Thick aluminium foil (re-cycled pie plates or foil trays are ideal) • Scissors, a sewing pin • two pieces of cork or polystyrene • a stick or wooden ruler • a blob of plasticine • an electric fan (preferably with 2 or more speeds) Use L49 It's not just wind or L77 Wind Power, Curriculum Corporation, 2006. The Le@rning Federation digital content L49 It's Not Just Wind L77 Wind Power For information about how to access these Learning Objects http://www.thelearningfederation.edu.au/for_teachers/access_information/access_information.html Record your learning about setting the blade length and angle of the blade to the wind to suit wind speed. Use your learning to design, build and test your own wind mill. Set Up: Cutting the foil to make the blades. Fan and windmill Method: Make the ‘blades’ of your windmill by cutting out a suitably-sized circle of foil. (If the factor you’re measuring is blade length, make your circle with the radius of your longest length. Then the same circle of blades can be made shorter to test varying blade lengths) Make a small hole in the centre of the foil circle. Cut the circle to make your blades. (If the factor you’re testing is number of blades, start with 4 and then you can add more cuts for more blades as you go along) Bend the blades into the shape On the sewing pin, in the following order, place a small piece of cork/polystyrene, the circle of blades, and another piece of cork/polystyrene. Pin this to the stick or ruler. Test to see that the ‘wheel of blades spins easily by blowing on it. Adjust the cork/polystyrene pieces if necessary. Place your ‘windmill’ upright on the bench using the plasticine. Place an electric fan close enough to your windmill to make the blades turn Record how much energy can be captured by observing how fast the blades on your windmill spin. If they turn very fast you might have to use a + system: +++++ for very fast, ++++ for fast etc.) Record your results: Factor being tested (e.g. blade length) Measurement of energy captured Average 12cm Trial 1 Trial 2 Trial 3   10cm                                       Discussion (complete the following statements): 1. To measure the amount of energy captured by the windmill we counted. . . 2. The fastest speed was achieved when… 3. The slowest speed was achieved when … 4. Other factors that affect the amount of energy captured by windmills are… Create a PMI chart for use of wind energy for power generation. Investigate areas around the world which would find wind generation possible. Assessment task Create a report which gives: A labelled diagram of your design along with measurements and a statement detailing why you have decided on the length and angle of the blades for your windmill. A report on testing procedures and the results you gained. A comment on why you think your design is a good one. A discussion about the positive and negatives for using wind power. Extension Investigate as many factors as you can think of (eg blade shape, the number of blades, the height of the windmill, the force of the wind, more than one set of blades) that might affect the amount of energy captured by a windmill. Then design the ‘ultimate windmill’ Try The Le@rning Federation’s L898 Wind farm: pros and cons