windmills

When fourteen-year-old William Kamkwamba's Malawi village was hit by a drought, everyone's crops began to fail. Without enough money for food, let alone school, William spent his days in the library . . . and figured out how to bring electricity to his village. Persevering against the odds, William built a functioning windmill out of junkyard scraps, and thus became the local hero who harnessed the wind.

harnessed.jpg

design challenge

ASK

How can we create a windmill to generate energy or do work? 

Students should engage in a Driving Question Board to elicit ideas and ask questions about what they need to know to answer this question and solve the problem. 

MATERIALS

​Simply Suggestions:

  • Popsicle sticks

  • Pipecleaners

  • Toothpicks

  • Felt

  • Cardboard

  • Corrugated cardboard

  • Magazine paper

  • Newspaper

  • Wax paper

  • Aluminum Foil

  • Printer paper

  • Motor

  • Multimeter

  • Styrofoam Ball 

  • PVC pipe

  • Fans (of varying strength)

PEOPLE

Encourage students to think about the users in the town with the windmill. The emphasis is not on the aesthetics in this challenge, the focus is much more on the efficiency of the windmill as a direct result of student designs of the blades. Students could later create a 2D illustration of the windmill to be more visually appealing for the town or multipurpose. 

IMAGINE

Students may draw experience and visuals from the wind turbines in their community. Some may connect thinking to traditional windmills of Holland, or pinwheels. Allow class discussion of considerations and ideas. As you read the story, students may realize the concept of weight, as William uses a lot of metal. This is an important aspect to elicit their initial thoughts on. 

Constraints

Your Choice: 

  • Create a blade for a windmill that will "catch the wind" 

  • Aim for it to catch as much wind as possible

  • Could set a constraint for the energy measured by the rotations 

PE aligned

PLAN

Teams should collaboratively plan in their notebook. To scaffold their thinking, first have them plan an investigation of shape and material as they design a singular blade. They will plan a structural material to hold the shape, and a material to be the surface area catching the wind. 

CREATE

Students will make a singular blade to test for the windmill. 

Including, but not limited to: 

  • Energy (conversion and transfer)

  • Electricity

  • Air / Wind

TEST

Set up the testing site: stretch a 10' string or fishing line between two tables or chairs, secure it and fasten it to the surface. You will need a binder clip or paper clip to hang from the string. Set up the fan behind one end of the string to push the blade. Students will hang their blade by the binder clip or paper clip. 

Choice: Time how long it takes to traverse the 10' OR See how far the blade goes in a set amount of time (dependent on how strong your fan is). 

ITERATE

Collect the class data and determine which patterns emerged as most effective in the blade design. Students will not improve the blade, but use this data to design a set for the generator. 

PLAN

Using their findings, they should fine tune their design for a wind turbine. At this time they will also need to consider what angle they will place the blade and how many they would like to utilize. 

CREATE

Students will make multiple blades and stick them in a styrofoam ball or foam disc to be attached to the motar and generator. 

TEST

Set up the testing site: Attach the motor to the PVC pipe and connect the multimeter to motor. As each team comes up you will attach their styrofoam ball or foam disc. Then start the fan to see how it spins. 

Data: Measure the energy generated and/or how many rotations it spins, if you are able to count (dependent on how strong your fan is). 

ITERATE

Collect the class data and discuss their findings. Have students reflect what changes they would make. Would they alter the angle? Were fewer or more blades successful? Was there any correlation of materials? Discuss how they feel weight might have affect it, and any patterns that emerge. 

additional texts

energy island.webp
harness wind chap.webp