1. Snohomish County PUD Mrs. Begeman (Ms. B)
The Power of the Wind
Snohomish County PUD
Mrs. Begeman (Ms. B)

2. Snohomish PUD
What does PUD mean?
P – Public
U - Utility
D – District

3. Today we are going to: Part 1: Science Part 2: Engineering
Think, talk and work like scientists/engineers
Part 1: Science
Answer a scientific question
10 teams - do 10 different controlled experiments at the same time
Present your findings
Part 2: Engineering
Design a solution using evidence
Divide into 5 teams of experts
Design your own blades
A water pumping contest

4. Natural Phenomena: Wind Energy
Wind Energy is the energy of MOTION
Wind is……..
AIR IN MOTION

5. Background for Wind Energy
Energy Now!

6. Does wind have power?

7. What are these things? What do you notice?
Propeller vs. turbine, transformed, Definition, tasks

8. Why would we want to build wind turbines?

9. How Electricity is Generated
FWEE: How Electricity is Generated:

10. How does a wind turbine work?
Inputs?
Outputs?

11. Rotor
Blades
Main Shaft
Gear Box
Generator
Tower
The other major part is the tower, which must be high enough
to capture the greatest wind velocity.

12. Wind Turbine Perspective
Tower

13. Turbines can be very small

14. Scientific/Engineering Practices (What we do in science/engineering)
Scientists and Engineers use all of these practices (what we do in science) when they do experiments or make designs. We will focus on one of them today. Developing and using models.

15. Developing and Using Models
What is a model?
How do models help us? Why don’t we just go out and start building wind turbines to experiment with?

16. What are we going to look for?
Find patterns in the output voltage that can be used as evidence and to make predictions for the best blade type.
Describe and compare the measured output voltages from the wind turbine when we change the manipulated variable (blades) in terms like: increased, decreased, larger, smaller
Crosscuts:
Patterns:
Patterns of change can be used to make predictions.
Patterns can be used as evidence to support an explanation.
Similarities and differences in patterns can be used to sort, classify, communicate and analyze simple rates of change for natural phenomena and designed products.
Scale, Proportion, and Quantity
Standard units are used to measure and describe physical quantities such as weight, time, temperature and volume.
Relative scales allow objects and events to be compared and described (eg. Increased, decreased, larger, smaller)
These are called Crosscuts in the NGSS standards.

17. Variable
A vari able is something that is able to vary (change) in an experiment

18. A Controlled Experiment or “Fair Test” changes only1
variable at a time.
Background from NGSS Standards Book: 3-5 Engineering Design: "Improving designs involves building and testing models or prototypes using controlled experiments or “fair tests” in which only one variable is changed from trial to trial while all other variables are kept the same. This is the same practice as in science inquiry, except the goal is to achieve the best possible design rather than to answer a question about the natural world. Another means for improving designs is to build a structure and subject it to tests until it fails; noting where the failure occurs and then redesigning the structure so that it is stronger. The broader message is that “failure” is an essential and even desirable part of the design process, as it points the way to better solutions."

19. Independent Variable...
(what we are changing)
It's the one we change on purpose. It's what we are testing. We can choose what the changed variable will be.
There can only be one!

20. Dependent Variable...
(what we are measuring)
is the result our investigation gives us. It has to be measured.
It's our data.
Voltage ~ 1.00 v

21. Controlled Variables What stays the same
Same Hub
Same type of material for the blades
Same type of sticks
Same brand of fan
Same brand of voltmeter
Same setup in the test stations
Many more……
1 meter from the front of the fan to the tower of the turbine

22. Setting the Pitch/Angle
Hub goes knob side up
Place the blade into the hub smooth side up.
Use the knob to tighten a little to hold the blade in.
Set the protractor onto the hub and blade.
Turn the blade to the right to measure the correct angle.
Knob
Hub

23. Teams 1 & 2: Number of Blades
Independent (changed) Variable:
Number of blades.
Dependent (measured) Variable:
Voltage (v) – amount of electricity
Controlled Variables:
Angle/Pitch: 30°
Shape: Trapezoid
Mass: 0 clips
Length/width: all the same
Hub
knob

24. Teams 3 & 4: Pitch/Angle of Blades
Independent (changed) Variable:
Pitch/Angle of the Blades
Dependent (measured) Variable:
Voltage (v) – amount of electricity
Controlled Variables:
Number of Blades: 3
Shape: Trapezoid
Mass: 0 clips
Length/width: all the same
5° ° ° °

25. Teams 5 & 6: Mass (weight) of Blades
Independent (changed) Variable:
Mass (weight) of the Blades
Dependent (measured) Variable:
Voltage (v) – amount of electricity
Controlled Variables:
Number of Blades: 3
Angle/Pitch: 30°
Shape: Trapezoid
Length/width: all the same
0 clips clip clips clips

26. Teams 7 & 8: Length/Width of Blades
Independent (changed) Variable:
Length/Width of the Blades
Dependent (measured) Variable:
Voltage (v) – amount of electricity
Controlled Variables:
Number of Blades: 3
Angle/Pitch: 30°
Mass of blades: 0 clips
Shape: Rectangle
8 cm
15 cm
15 cm in length
8 cm in length
Surface Area is controlled
18 cm
11 cm
11 cm in length
18 cm in length

27. Teams 9 & 10: Blade Shape Independent (changed) Variable:
Shape of the Blades
Dependent (measured) Variable:
Voltage (v) – amount of electricity
Controlled Variables:
Number of Blades: 3
Angle/Pitch: 30°
Mass of blades: 0 clips
Length/Width: all the same
Rectangular (rectangle)
Beveled (trapezoid)
Triangular (triangle)
Circular (circle)

28. Science starts with a question
Science starts with a question. How does brand of fishfood affect fishes’ growth rate?
The variable we are changing is the brand of fishfood
The variable we are measuring is fishes’ growth rate.

29. On your sheet fill in your team’s Independent (Changed) Variable?
Teams 1 and 2 will change the Number of Blades
Teams 3 and 4 will change the Pitch (angle) of the Blades
Teams 5 and 6 will change the Mass (weight) of the Blades
Teams 7 and 8 will change the Length of Blades
Teams 9 and 10 will change the Shape of the Blade

30. Hint: The data chart shows the answer! (Voltage, volts)
What are you measuring?
Fill in the second question on your sheet.
Hint: The data chart shows the answer!
(Voltage, volts)

31. Using the information below, fill in your team's controlled variables
Mass = 0 clips
Angle = 30°
# of blades = 3
Shape = Trapezoid (Beveled)
Length = just write “all the same”

32. Thinking about your prediction
Fill in the blank with what you think will produce the most electrical voltage on our test station.
Teams 1 & 2: , 3, 4, or 6 blades?
Teams 3 & 4: 5°, 10°, 20° or 45°
Teams 5 & 6: clips, 1 clip, 2 clips or 3 clips
Teams 7 & 8: cm, 11 cm, 15 cm or 18 cm
Teams 9 & 10: rectangular, triangular, circular, trapezoid
You DO NOT change your prediction

33. Testing Procedure
Make sure the blades are pressed onto the hub tightly, listen for a click
Measure angles, tighten hub, check angles again
Have an adult check your angles/pitch for the first several trials.
At the test station
Have an adult gently put your hub onto the rotor.
Do NOT stand to the side or on top of the blades!
One person turns the fan on and times for 20 seconds.
The other person reads the voltmeter.
The number will bounce around, use the largest reading you see.
Turn off the fan.
Have an adult remove your blades by gently pressing on the back of the hub.
Record your data!
Return to your team and set up the next measurement.
The teacher should do this with me. We will demonstrate how to do it and standard mistakes. Blocking the air to the fan, tower not straight up. Blades not at correct angle, standing in wrong position near blades, person at the fan not timing, person at the tower not reading voltage the WHOLE time (glancing down and away), students removing the blades. Not recording the data.

34. When you are finished with your blade testing…
Fill in your data chart.
Remember – be very accurate, you need this data to design your blade!
Look for a trend (pattern) in the data.
Compare your trend with your partner team? Retest if necessary.
Put all materials back into your box.
Work together to finish writing the claim/conclusion.
If you finish early, complete the answers to the questions on page 2.
Finish Time: ___________________

35. Presentations
Each group will send a representative to share the team’s claim.
We will record the findings on the Expert Board.
You will use this data as your evidence for part two when you design your own blade.

36. What blade variables do you think could affect electrical output?
Number of blades
Blade pitch
Blade mass
Materials used
Blade length
Blade shape/surface area
Blade twist

37. You are now an EXPERT! Be ready for your next JOB!
What variable were you testing? Did this variable have an effect on electrical output?
What blade design do you recommend would be the best? Show the evidence that proves that your recommendation a good one.

38. Part 2 – Engineering – Designing a Better Blade
Switch into 5 Engineering Teams.
How is science different than engineering?
"Is the goal to answer a question? If so, students are doing science. Is the purpose to define and solve a problem? If so, students are doing engineering.“
After you design and test your blade, your best design will be entered into a pumping contest that will determine which group’s blades will be used in the company’s design!

39. Engineering Design Process

40. Design - Specify criteria and constraints that a possible solution to a simple problem must meet.
Criteria (Requirements / What it/you has/have to do):
Blades must gather wind energy to be transformed (converted) into electrical energy. Most output voltage you can transform.
Consider at least the 5 variables researched in expert groups
Work as a team and ensure each person’s input into the design.
Constraints (limitations to consider):
Time – 40 minutes
Materials – 1/2 piece of cardboard and 1 stick per blade
no major redesign of blade shape or size ( because of time )
Model of wind in the form of a fan

41. What materials will you have?
Each team has their bag of design tools. This contains:
A hub
A protractor
Ruler (s)
Vis a vis markers to use to write your design on your Expert Board
2 pairs of scissors
Once your design is complete and a teacher/adult has cleared it, you will get ½ sheet of cardboard for each blade and a stick for each blade.

42. Develop Solutions – Research and explore multiple possible solutions.
Discuss the possible solutions letting each person use the data from the science experiment as their evidence.
Draw out a design that you agree on on your Expert Board
Start by filling in the circles on top.
When you draw your diagram, remember to label all the parts of your design including lengths and widths for the pieces.
Get the design approved by a teacher.
As a team, make the Blades:
Draw your design on the cardboard before cutting
Suggestion: Cut one blade out and use that to trace the other blades.
Trace where you want your stick to be on your blades (make sure all the stick/blades match) and get the sticks glued on. (Adults will glue)

43. Optimize - Improve a solution based on simple (fair) tests, including failure points.
Do a first (initial) trial and record the output voltage.
Optimize (change) the design to increase voltage
Mass
Number of blades
Angle/pitch of the blades
When adjusting the angle/pitch, turn the stick so you don’t damage the cardboard.
Perform a series of “Fair Tests” to see if you can improve the voltage output of the generator using your blades.
Record the results of each fair test to use to determine the optimal (best) design.

44. Blade Competition

45. We will now use our model turbines to generate electricity.
Let's see which team can pump the most water!

46. What do gears do?
Video that explains gearing in a wind turbine:

47. Blade Competition 1 50 2 3 4 5 Team Time(seconds) mL H2O
Tips if not pumping water:
Check gearing to make sure gears are tightly pressed together, the support nuts work their way loose
Check angles on blades to see that they are going the right way.
Disconnect the load from the pump to let the blades build up some speed, reconnect the load

48. What were the 5 different blade variables tested today?
Number of blades
Angle/pitch of the blades
Weight/mass of the blades
Length of the blades
Shape of the blades

49. What other variables do you think affect the power output from wind turbines?
Wind speed
Generators
Size of turbine
Gear ratio
Location
Blade design

50. Limitations of Models
What are some of the limitations of our test setup model compared to a large wind turbine in Eastern Washington?
What could we do to improve our model to make our data closer to what we might find in a real wind turbine?

51. Using Wind to generate electricity Disadvantages Advantages
ETS2.B: Influence of Engineering, Technology, and Science on Society and the Natural World
Using Wind to generate electricity
Disadvantages
Advantages
Disadvantages: (1) Can be loud (2) Some people don’t like that they break up the horizon (3) There is not always wind (4) Large amount of materials to dispose of if no longer needed. (5) Birds can get hit by blades, doesn’t happen hardly at all anymore but was a problem at first when the blades were spinning faster
Advantages: (1) Renewable (2) Wind doesn’t cost anything (3) Once the turbine pays for itself, you only have maintanence cost, the wind is free. (4) Off shore wind farms allow for coasts to have energy source near large cities

53. Influence/Impact on natural world: Takes a lot of materials to build
Influence/Impact on natural world: Takes a lot of materials to build. Can supply a lot of electricity.

54. How is a wind farm part of the entire electricity-generating system?

55. Tell his story and stress how his design created advantages for his family and people. He created technology based on his needs and desires.

56. ETS2.A: Interdependence of Science, Engineering, and Technology
Science and engineering are intertwined. Two scientists are standing on a beach and see this boat being propelled forward by the wind. One says, “It sure looks like there is a lot of wind out there. I wonder how much wind there is?” The two them decide to find out. They do a series of “fair tests” to determine how much wind is out there. They record their results and make a map with the wind levels in different part of the US. (See next slide)
Science answers questions about nature, they use technology to do research
Technology is any modification of the natural world made to fulfill human needs or desires.

57. How much wind is there?
Their data is displayed on a map and the map is published for people who are interested to use.

58. Two engineers are standing on the same beach
Two engineers are standing on the same beach. They look out and see the same boat. One says, “It looks like there is a lot of wind out there. I think we could design something to transform that wind power into electrical power to help solve the electricity shortage in this area.” They need information to determine if there is enough wind and to know where to try to build their design.
Engineering is a systematic and often iterative approach to designing objects, processes and systems to
meet human needs and desires.
An application of science is any use of scientific knowledge for a specific purpose, whether to do more science; to design a product, process or medical treatment; to develop a new technology; or to predict the impacts of human actions .

59. Where are wind projects built?
They research and discover the map that the scientists drew for how much wind is off the shore and decide to explore some possible designs for transforming that wind into electricity.

60. Engineering designs things to solve problems
They come up with multlple possible designs and choose one to test and see if it is effective. They start using models to see if the idea will work.
Engineering designs things to solve problems

61. As I said, science and engineering are intertwined
As I said, science and engineering are intertwined. Those scientists who answer the question about how much wind is out there? How do you think they measured that? Using devices built by engineers. How did the engineers get the information to make those devices? From data from scientists. The research and resulting information provided by scientists allows engineers to design new forms of technology that change what is possible. Those new devices make it possible for scientists to research new things and provide more information. This cycle continues.
Science and Engineering provide information/ devices (technology) that allow both to keep making new discoveries/designs.

62. Name other blade variables that were not tested today

63. What other variables (besides blades) could be tested?

64. Discussion Questions
What variable has the greatest impact on power output?
Can the data we collected today be related to full scale wind turbines? How?
What are some advantages and disadvantages of wind power?
What is the one thing you will remember the most about today’s lesson?