Working with Wind Energy Stirling: March 2011 Nico Beute 1

Activity Goal Build a wind turbine with simple materials The wind turbine must withstand the wind generated by a fan or hair dryer and rotate for up to 1 minute to lift a small object 2

Activity Objectives Learn about wind energy conversion Design a wind turbine Construct the wind turbine Test the wind turbine Evaluate Performance 3

Why is this experiment useful to teachers and students? Learn about wind energy and wind turbines Learn about the concepts of forces and motion Learn about engineering design Learn how engineering can help solve societal challenges Learn about teamwork and problem solving 4

Principles & Standards for School Mathematics Geometry: – Use visualization, spatial reasoning, and geometric modeling to solve problems – Analyze characteristics and properties of two- and three- dimensional geometric shapes and develop mathematical arguments about geometric relationships Problem Solving: – Recognize and apply geometric ideas in areas outside of the mathematics classroom – Apply and adapt a variety of appropriate strategies Communication: – Communicate mathematical thinking coherently and clearly to peers, teachers, and others 5

What is Wind? Wind is a form of Solar Energy The sun heats the Earth’s surface at varying rates The air above the warmer areas heats up, becomes less dense and rises Cooler air from adjacent higher-pressure areas moves to the lower-pressure areas That movement = wind 6

Where in the World is Wind? 7

What is Wind Energy? The process by which the wind is used to generate mechanical energy or electricity Wind turbines convert the kinetic energy in the wind into mechanical and electrical energy 8

SEP 20109

A Wind Turbine The wind hits the blades… Shaft leads to a gearbox whose output leads to a generator to make electricity Usually has 2 or 3 blades 10 WIND

The Turbine Blade Operates much like an airplane wing Low-pressure air forms on the downwind side of the blade The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn 11

Many blade designs 12

Objective To enable engineers to lead a training session for teachers on an engineering related topic

Engineers: Understand the educational system – Educational terms Curriculum Outcomes {CO, DO & LO} Assessment standards – Educational environment Knowledge of learners Knowledge of teachers

How Make it practical – give examples from the workplace Keep it simple Try it out today

Consider the environment Where do we get energy from? Is our energy source sustainable? Do we want nuclear energy? Is wind energy affordable? What types of energy harm our environment? Do we consider social and economic issues? SEP

Your Challenge Design, construct and test your own wind turbine design Lift weight – 15 cm as quickly as possible Maximum 1 minute No human interaction! Blowdryer at least 30cm away from turbine 17 > 1ft, 30cm

Materials wooden sticks, spoons bendable wire string paperclips rubber bands toothpicks aluminum foil, plastic wrap tape, glue wooden dowels paper, cardboard 18

Turbine Requirements Must have a rotor shaft around which to wind up given weight Must be freestanding (no human interaction) Must use only materials provided 19 > 1ft, 30cm

Test Procedure Blowdryer at least 30 cm away from turbine No human interaction with turbine Attach weight around rotor Up to 1 minute to wind up weight for 15cm Record time to wind up weight 20 > 1ft, 30cm

Procedure Teams of 3, at least 1 teacher per group Be a primary school learner Consider educational principles Develop and sketch your design Construct initial design Preliminary test Modify design, if necessary Final test - Show Yvonne 21

Evaluate Your Design Efficiency of design may depend on – Cost of materials – Speed (rotations per minute) – Power (time to wind weight) Possible measure of efficiency: – Eff. = (Cost of materals) / (time [sec] to wind weight) Are two designs that have the same rotational speed equally as “good”? 22