Solar Energy Lesson Plan

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THE
 TEAK
 PROJECT:
 
 
TRAVELING
 ENGINEERING
 ACTIVITY
 KITS
 


 


 

Solar Energy

Partial support for this project was provided by the National Science Foundation's Course, Curriculum, and Laboratory
Improvement (CCLI) program under Award No. 0737462. Any opinions, findings, and conclusions or recommendations
expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science
Foundation.

Partial support for this project was provided by the American Society for Heating, Refrigeration, and Air-Conditioning
Engineering (ASHRAE) through a Senior Projects grant. Any opinions findings and conclusions or recommendations
expressed here are those of the author(s) and do not necessarily reflect the views of ASHRAE


 

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Solar Energy Lesson Plan

Page 2

ACTIVITY OVERVIEW
Solar Energy Kit Overview
Do you enjoy a nice, sunny day? During this activity, you will use sunlight to do more than brighten your day!
Students will learn the difference between solar power and solar heat, and will use the sun’s energy to power
small electrical devices and create a small passive solar device to warm up a lost sled-dog racer. They will even
get to see how RIT uses solar passive heating in the new buildings that are being designed and built! NOTE: This
lesson plan has many of the same concepts and activities found in the Heat Transfer Lesson Plan. Some of
the activities are duplicated.

Activity

Time

Solar Power

20 min

Solar Heating Design

20 min

Lesson Extender: Solar Cell Model

20 min

Description
The students will be provided with a small photovoltaic cell
and an alarm clock. They will use the PV cell to run the
alarm clock, instead of the battery that is normally used.
Students will change the amount of light collected, in order
to determine optimum operating conditions.
This design scenario takes place in chilly Alaska. Stranded
by her team of dogs, Emmy is left with only a sled and some
supplies. The students must find the material that will best
help her to use the sun’s energy to stay warm.
Students act out the workings of a solar cell, by role-playing
the energy from the sun and the electrons within a solar cell.
Student movements will demonstrate how the solar cell
actually work to create electricity.

Learning Objectives
By the end of this lesson, students should be able to…
• Explain what solar energy is
• Describe the needs and limitations of solar energy
• Explain the difference between solar heat and solar electricity
• Understand the basics of solar passive design
• Work in teams to complete a design scenario

NYS Learning Standards
Standard 1: Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to
pose questions, seek answers, and develop solutions. Students will:
• Interpret organized observations and measurements, recognizing simple patterns, sequences, and
relationships
• Discuss how best to test the solution; perform the test under teacher supervision; record and
portray results through numerical and graphic means; discuss orally why things worked or did not
work; and summarize results in writing, suggesting ways to make the solution better
Standard 4: Energy exists in many forms, and when these forms change energy is conserved. Students will:
• Describe the sources and identify the transformations of energy observed in everyday life
• Describe situations that support the principle of conservation of energy
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Solar Energy Lesson Plan

Page 3

TABLE OF CONTENTS
 
Instructor Preparation Guide.................................................................................................................................. 4
 
Important Terms ..................................................................................................................................................... 4
 
Background Information......................................................................................................................................... 8
 
Simplified Definitions ............................................................................................................................................ 8
 
Solar Energy Group Discussion ............................................................................................................................. 8
 
Solar Power Introduction ........................................................................................................................................ 9
 
Simplified Definition .............................................................................................................................................. 9
 
Solar Power Group Discussion ............................................................................................................................... 9
 
Learning Objectives .............................................................................................................................................. 10
 
Materials ............................................................................................................................................................... 10
 
Procedure .............................................................................................................................................................. 10
 
Safety Precautions ................................................................................................................................................ 12
 
Procedure .............................................................................................................................................................. 13
 
Solar Heat Introduction ......................................................................................................................................... 15
 
Simplified Definition ............................................................................................................................................ 15
 
Solar Heat Group Discussion ............................................................................................................................... 15
 
Learning Objectives .............................................................................................................................................. 16
 
Materials ............................................................................................................................................................... 16
 
Setup Procedure .................................................................................................................................................... 16
 
Safety Precautions ................................................................................................................................................ 16
 
Procedure .............................................................................................................................................................. 16
 
Concluding Discussion ......................................................................................................................................... 18
 
Trouble-Shooting Guide ....................................................................................................................................... 18
 
Solar Energy Kit ..................................................................................................................................................... 19
 
PV Cell Introduction .............................................................................................................................................. 20
 
Background Information....................................................................................................................................... 20
 
Simplified Definition ............................................................................................................................................ 20
 
Group Discussion ................................................................................................................................................. 20
 
Learning Objectives .............................................................................................................................................. 20
 
Materials ............................................................................................................................................................... 21
 
Procedure .............................................................................................................................................................. 21
 
Activity Extenders ................................................................................................................................................ 21
 
Concluding Discussion ......................................................................................................................................... 22
 
Solar Activity Handout .......................................................................................................................................... 23
 
Solar Activity Handout (ANSWERS) ................................................................................................................... 24
 
Keeping Heat In Design Activity ........................................................................................................................... 25
 
Keeping Heat In Desing Activity (ANSWERS) ................................................................................................... 26
 
Image Sources ......................................................................................................................................................... 27
 
Revisions .................................................................................................................................................................. 28
 

Signifies Group Discussion

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Signifies Activity

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Solar Energy Lesson Plan

Page 4

INSTRUCTOR PREPARATION GUIDE
Important Terms
Solar Energy
Solar energy is radiant energy from the sun that reaches the Earth. This radiant energy can be collected and
converted into other forms of energy, such as heat and electricity. Solar energy is found all over the Earth, which
makes it the most abundant energy source. While sunlight is readily available during the day, one of the
drawbacks of solar energy is that it isn’t available at night. Also, weather patterns can affect the amount of
sunlight that reaches the Earth’s surface.

Solar Heat
Solar heat is the collection of solar energy to heat, air or a fluid. There are two types of solar heat collection:
active and passive. Active solar heating requires solar energy to be collected in a fluid, and then the heat is
transferred directly to a living space or storage system. Radiant floor heating is an example of this system. An
antifreeze solution is piped through collectors on the roof of a building, where the sun’s heat is absorbed. The
antifreeze solution is then pumped through pipes in the (concrete) floor of a room. The heat in the antifreeze is
transferred into the concrete and then into the air of the room, heating it up. Passive solar heating doesn’t require
the use of mechanical and electrical devices to move the heat. An example of passive design can be seen in a
house with large, south facing windows (in the Northern Hemisphere). In the room(s) where the large windows
are, there also has to be material to absorb the heat. Such materials can be concrete, tile, or a water container.
When the sun shines into the room, the material absorbs the solar heat. All the heat that is stored is then slowly
released into the room, therefore keeping it at a steady temperature. The way the overhang of a house is designed
is important too. The overhang will allow the sun into the large windows during the winter, when heat is needed,
and keep the sun out during the warm summer months.


 

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Solar Energy Lesson Plan

Page 5

Solar Power
Solar
 power
 is
 the
 result
 of
 turning
 solar
 energy
 into
 electricity.
 Solar
 power
 is
 generated
 through
 
collecting
 the
 sun’s
 rays
 in
 a
 PV
 panel,
 and
 then
 the
 cells
 in
 the
 panel
 convert
 the
 energy
 into
 electricity.
 
Solar
 power
 can
 be
 used
 to
 run
 anything
 that
 needs
 electricity,
 from
 ovens
 to
 lights
 to
 TVs.
 While
 PV
 panels
 
are
 most
 commonly
 seen
 on
 individual
 homes
 and
 businesses,
 companies
 in
 very
 sunny
 areas
 are
 
beginning
 to
 create
 solar
 power
 generating
 plants.
 
 These
 plants
 are
 made
 up
 of
 acres
 of
 PV
 cells
 that
 
generate
 electricity
 for
 the
 surrounding
 areas.
 
 One
 challenge
 with
 this,
 however,
 is
 the
 fact
 that
 the
 energy
 
can’t
 be
 stored
 for
 nighttime
 usage.
 One
 solution
 that
 is
 being
 studied
 is
 the
 storage
 of
 the
 sun’s
 energy
 in
 
tanks
 of
 molten
 salt.
 While
 this
 technology
 is
 not
 yet
 proven,
 it
 shows
 that
 there
 is
 great
 potential
 for
 solar
 
power
 plants
 that
 can
 produce
 energy
 around
 the
 clock.
 
 

 


 

Photovoltaic (PV) Cells
Photovoltaic cells, or solar cells, capture solar energy and convert that energy into electricity. A PV cell captures
energy by using the energy from the sun’s rays to try and bump an electron off the solar cell. The electron that
was bumped then forces the electrons in front of it to move, causing a chain reaction known as current. A single
cell produces only a small amount of energy, so the cells are usually combined into larger groups known as
panels. Multiple solar panels can then be combined into larger groups called arrays. The ability to change the
number of cells/panels in a grouping allows for the size of the system to be customized.


 


 

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Solar Panel Orientation
As with solar passive design, solar panels should face south when being used in the Northern Hemisphere. They
also need to be mounted at an angle in order to maximize the amount of sunlight they can capture (therefore
maximizing the amount of electricity they produce). For general applications, such as mounting on the roof of a
house, the panels should be placed at an angle equal to the latitude at which the house is located. For more
advanced applications, the solar panels can be mounted on moving brackets that change their angle based on the
sun’s location throughout the day. This is typically done in large-scale solar power plants to maximize their profit.

Solar Passive Design
Solar
 passive
 design
 uses
 the
 energy
 from
 the
 sun
 to
 regulate
 the
 systems
 of
 a
 house
 or
 building
 without
 
the
 use
 of
 active
 systems,
 such
 as
 pumps
 or
 fans.
 Solar
 passive
 design
 is
 complex,
 and
 requires
 detailed
 
planning
 to
 lay
 out
 the
 building
 in
 a
 way
 that
 will
 be
 functional
 for
 both
 solar
 and
 living
 purposes.
 The
 
design
 of
 the
 house/building
 uses
 large,
 south
 facing
 windows,
 thermal
 mass,
 and
 natural
 heat
 transfer
 to
 
keep
 the
 interior
 at
 a
 comfortable
 living
 temperature
 (as
 discussed
 in
 the
 Solar
 Heat
 section,
 above).
 While
 
there
 is
 more
 that
 goes
 into
 solar
 passive
 design
 besides
 south
 facing
 windows,
 it
 is
 one
 of
 the
 most
 
recognizable
 characteristics
 of
 a
 solar
 passive
 house/building.
 


 


 
 
 
 
 


 
 
 
 
 
 
 

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Solar Energy Lesson Plan

Page 7

Solar Energy

DURATION
55-65 Minutes

CONCEPTS
Solar Energy
Solar Energy Usage
Solar Heat vs. Solar Power
Photovoltaic Cells/Panels
PV Orientation
Solar Passive Design

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SOLAR ENERGY INTRODUCTION
Background Information
Solar energy is radiant energy from the sun that reaches the Earth. This radiant energy can be collected and
converted into other forms of energy, such as heat and electricity. Solar energy is found all over the Earth, which
makes it the most abundant source of energy. While sunlight is readily available during the day, one of the
drawbacks of solar energy is that it isn’t available at night.

Simplified Definitions


Solar Energy
o Solar energy is radiant energy from the sun that reaches the Earth.
o This radiant energy can be collected and converted into other forms of energy, such as heat and
electricity.

Solar Energy Group Discussion
(Pose the following questions to the group and let the discussion flow naturally…try to give positive
feedback to each child that contributes to the conversation.)

Q: How is solar energy used?






To heat buildings, homes, water
To light buildings, homes
To generate electricity using PV panels/cells
To cook food (especially while in remote areas/areas without electricity)
The sun's energy also keeps the Earth at a temperature to support life.

Q: What are the benefits of solar energy?





Solar energy is always there during the day.
Solar energy is free.
Solar energy does not create any sort of pollution when it creates electricity.
Can be more correct answers than the ones listed.

Q: What are the disadvantages of solar energy?




The battery technologies around today are not efficient at storing the energy created.
Solar energy cannot be harvested at night or during cloudy days.
Can be more correct answers than the ones listed.

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SOLAR POWER INTRODUCTION
Simplified Definition
Solar Power
• Solar power is the conversion of the sun’s energy into electricity.
• The result of changing solar energy into electricity.
• Solar power refers to any energy that is harvested from the sun’s light.
Photovoltaic (PV) Cells
• Photovoltaic cells, or solar cells, capture solar energy and convert that energy into electricity.

Solar Power Group Discussion
(Pose the following questions to the group and let the discussion flow naturally…try to give positive
feedback to each child that contributes to the conversation.)

Q: How do you think solar power can be used?







To run a furnace to heat homes/buildings
To cook in an oven
To run lights
To run appliances (TV, stereo, computer, etc…)
To run anything that requires electricity
There can be more correct answers than the ones listed.

Q: What do you think some disadvantages of using a PV cell could be?





Solar power can’t be generated at night.
The current photovoltaic cells only capture about 12% of the light that shines on their surface. And of
that 12% only a small amount is actually useable as electricity.
Storage methods are not efficient.
If the PV cell gets blocked (by clouds, snow, etc…) they will produce less electricity.

Q: Do you think solar power could be stored to use at night time? How?




 

Yes, solar power can be stored.
The energy is most often stored in rechargeable batteries.
o These batteries need to be able to be charged over and over.
New technologies are being developed to store solar power at night
o Example: Storing the sun’s heat in tanks of molten salt during the day and using the heat to make
electricity at night

 

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Solar
 Power
 Activity
 –20
 Minutes
 

Solar Energy Lesson Plan

Page 10

Learning Objectives
By the end of this exercise, students should be able to…
• Understand the concept of solar power
• See/understand how photovoltaic cells convert sunlight into electricity
• See the difference between ideal and non-ideal solar catching conditions

Materials
Each group gets:
• (1) Solar panel
• (1) Alarm clock
• (2) Alligator clips
Other materials:
• (3) Clip lamps
• (1) Surge Protector
• (3) Laminated Test Layouts
• (3) Multi-meters

Procedure
(For instructor’s purpose only...DO NOT have students help with this)
1. Room Arrangement
This activity requires 3 working stations. They all need to be around a central location so that the power
cords will reach.
a. Design A
The activity was designed and tested with the clip lamp attached to the back of a chair and the
materials set up on a table. This setup allows the students to see what is happening and to easily
manipulate the activity.

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b. Design B
If the desks and chairs cannot be moved, using only chairs is a suitable alternative.

2. Clip Light Arrangement
Make sure that the clip lamps are set up facing away from each other so that they don’t interfere with
other groups’ thermal crystals.
a. Attach the clip lamp to the back of the chair.

3. Structure Arrangement
a. Place one test layout at each workstation. Make sure that the layout is in proper position, and then
tape it down. The structures/solar panels will go in the labeled boxes on the test layout.

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4. Shade Orientation
The orientation of the lampshade is critical.
a. Place a K’NEX structure in the labeled box on the test layout. The face of the lamp needs to be
parallel to the red rods on the K’NEX structure. While it doesn’t have to be perfect, use the
structure to get the shade as parallel as possible.

b. Another way to get the shade in proper position is to make sure that there is just enough room
between the silver clamp arm and the lampshade to fit your fingers.
c. Make sure that the shades are tightened so they don’t slide.

Safety Precautions
The lamps get very hot! Instruct the students NOT to touch the lamps for any reason. They should ask for
assistance if they need to adjust their lamp. The lamps are very bright! Instruct students NOT to look
directly into the light.

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Procedure
1. Have the students help move desks/chairs to create three workstations.
2. Give a kit and an activity handout to each group.
3. Have the students work in their groups to answer the questions on the top of the handout.
a. While the groups are doing this, the instructor should set up the three clip lamps (making sure that
each lamp is set up to allow enough working space for two groups). The instructor should attach
each lamp to the surge protector, and plug it in (making sure to switch it off). The instructor
should also set up a test layout at each test station. See Setup Procedure for more details.
4. Tell the students that their answers to the warm-up questions will be answered by the activity.
5. Assign each group to a clip lamp. Have the groups bring all their materials to their assigned lamp and take
everything out of the kit box.
Read the instructions to the students step by step. Have a different student perform each step. Have
students raise their hands after they complete a step so the instructor knows to move on.
6. Take everything out of the kit box.
7. Attach the alligator clips to the wires on the solar panel.
8. Attach the clip of the red wire to the red wire on the alarm clock. Attach the clip of the black wire to the
black wire on the alarm clock.
9. INSTRUCTOR: Flip the switch on the surge protector to turn on the lamps.
10. Place the solar panel in Box 1 on the test layout. Make sure it is in position A. Also, make sure that the
alarm clock is positioned to the side/behind the solar panel.
11. Observe the numbers on the alarm clock. Do the numbers completely light up? Write any observations in
the table on the activity handout.
12. Change the solar panel to positions B and C and repeat step 11.
13. Place the alarm clock in Box 2 on the test layout. Make sure it is in position A. Also, make sure that the
alarm clock is positioned to the side/behind the solar panel.
14. Observe the numbers on the alarm clock. Do the numbers completely light up? Write any observations in
the table on the activity handout.
15. Change the solar panel to positions B and C and repeat step 14.
16. Put the solar panels back into position A. Complete the action table by performing each action and
observing what happens to the clock.

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Solar Energy
Lesson Plan
End
 Solar
 Power
 
Activity
 

Page 14

17. Now the 2 groups at each station will have to work together! Take one group’s solar panel and alligator
clips. Attach the clips to the test leads on the multi-meter (make sure colors match). Make sure the panel
is in position A.
a. INSTRUCTOR: Go to each group and check that the wires are attached properly and turn the
multi-meter to the 20V setting.
18. Put the solar panel in between the two Box 2’s (so that it is centered on the test layout).
19. Read the voltage off the multi-meter and record it in the Box 2 table.
20. Switch the solar panel to positions B and C and repeat step 19.
21. INSTRUCTOR: Switch off lights.
22. Answer the three questions on the bottom of the handout.
***Keep solar panel/clock setup together because it will be used in the next activity.

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SOLAR HEAT INTRODUCTION
Simplified Definition
Solar Heat



Solar heat is the collection of solar energy to heat air or a fluid
Active Solar Heating



Active solar heating requires solar energy to be collected in a fluid and then the heat is transferred directly
to a living space or storage system.



Uses mechanical devices (fans and pumps) to move the air/fluid.
Passive Solar Heating



Passive solar heating does not require the use of mechanical and electrical devices to move the heat.

Solar Heat Group Discussion
(Pose the following questions to the group and let the discussion flow naturally…try to give positive
feedback to each child that contributes to the conversation.)

Q: Can anyone think of an example of active solar heating?




Solar pool heater
o The pump moves the water through a black panel or black tubing, allowing the sun to warm it
before going back into the pool.
Solar hot water heater
o Same concepts as pool heater except that the water goes into a hot water tank in the basement of
the house.

Q: Can anyone think of an example of passive solar heating?




A home with large glass windows that face south (in the Northern Hemisphere)
o These windows allow sunlight to heat the home. If a home is insulated properly, the heat gained
from passive heating can be contained within the house for a long time.
A car sitting in the sun
o The windows of a car allow the sun’s rays to get in, but the heat can’t escape.

Q: Do you think solar energy can be used to cook food?



YES!
A solar oven utilizes the greenhouse effect.
o Energy from the sun shines through the glass of a solar oven.
o The inside of the oven is a black metal, which absorbs the energy and changes it to a different
frequency.
o The glass does not allow the heat energy at the new frequency to come out.

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Solar
 Heating
 Design
 A
ctivity
 

 20
 
Minutes
 
Solar
Energy
Lesson
Plan

TEAK

Page 16

Learning Objectives
By the end of this exercise, students should be able to…
• See how light rays can be turned into heat by using thermal crystals
• Work together to complete a design activity
• Better understand the concept of passive solar design

Materials
Each group gets:
• (1) K’nex structure
• (1) Bag of materials
• (2) Thermal crystals
• (1) Solar Panel/Clock Setup
Other materials:
• (3) Clip lamps
• (1) Surge Protector
• (3) Laminated Test Layouts

Setup Procedure


**See Solar Power Activity**

Safety Precautions
The lamps get very hot! Instruct the students NOT to touch the lamps for any reason. They should ask for
assistance if they need to adjust their lamp. The lamps are very bright! Instruct students NOT to look directly
into the light.

Procedure
1. Have the students return to their groups. Pass out a structure, test materials bag, and activity handout to
each group.
2. Read through the design scenario with the students. Make sure that everyone understands the activity.
3. Have the students take the materials out of the bag. As a group, they should decide on three materials that
they think best meet the design criteria. They should write their materials in the table on the activity
handout.
a. While the groups are doing this, the instructor should make sure that the workstations are still set
up correctly. The angle of the lampshade should especially be checked, since the shades can to
move fairly easily.
4. Have the students bring their structure, materials, and thermal crystals to their lamp.
5. The instructor should remind the students that the lamps get hot, and they are not to touch them for any
reason.
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End
 Solar
 Heating
 
Design
 Activity
 

Page 17

Read the instructions to the students step by step. Have a different student perform each step. Have
students raise their hands after they complete a step so the instructor knows to move on.
6. Record the color of the room temperature thermal crystal. When the lamp is turned on, all students will
need to watch the thermal crystals and see the order in which they change colors.
7. Place the thermal crystal in the structure box on the test layout.
a. (This is done with no insulation so the students can see how the crystals change color.)
8. INSTRUCTOR: Flip the switch on the surge protector to turn on the lamps, and then count to 15. When
15 seconds are up, flip the switch back off.
9. Record the color of the heated crystal.
10. Put the K’NEX structure in the appropriate box on the test layout.
11. Put a thermal crystal into the structure.
a. (Make sure that the students hold the crystals on the sides, so as to transfer as little heat as
possible to them.)
12. Put a material onto the structure. It should be resting on the green pegs and leaning back against the
incline.
a. INSTRUCTOR: Quickly walk around to make sure that all materials are leaning against the
structure so that the thermal crystal will be covered.
13. Put the solar panel into Box 1 on the test layout. Make sure the clock is to the side/behind the solar panel
and in a place where the numbers can be read.
14. INSTRUCTOR: When everyone is ready, flip the switch to turn the lights on and remind the students not
to look into the light. Start the timer/watch the clock when the lights are switched on.
a. When the lights are flipped on, have one student from each group watch the clock. When the
clock changes to the next minute, they should let their group know that one minute is up. The
teacher will be timing also to make sure that each material isn’t being tested for much more than
1 minute (a little over is ok).
15. INSTRUCTOR: When (approximately) one minute is up, turn the lights off.
16. Remove the material from the K’NEX structure and look at the color of the thermal crystal.
a. (This needs to be done quickly, so that the crystal doesn’t start to change colors.)
17. Record the color of the thermal crystal.
18. INSTRUCTOR: Repeat steps 11-16 so the students can test their other two materials.
a. It may be necessary to repeat the experiment a 4th time, in case groups mess up on one of their
tests.

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Solar Energy Lesson Plan

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Concluding Discussion
Q: What material do you think is best to keep the heat in Emmy’s shelter?



Sandwich Bag
Tarp

Q: Why do you think these materials worked best?



They are clear and plastic, so they allow radiation in but don’t let heat escape.
They are not reflective (like the wrapper) so they allow radiation through them.

Q: Did you expect these materials to work best? Why or why not?


Can be whatever answer the think is correct.

Q: Do you think the idea of trapping radiation/heat is used in engineering today?



YES! Passive Design
Engineers and architects use large windows that face the sun to heat up buildings in the winter. The
buildings include special overhangs to allow the sun to come in during the winter and to keep it out
during the summer.

Q: If you were going to build a structure to try to keep heat out, which materials would work best? Why?



Insulated foil because the air filled pockets disrupt the heat transfer and the reflective surface keeps
radiation from getting through.
The energy bar wrapper because it reflects the radiation rays away.

Trouble-Shooting Guide
1. Crystals turn color without being touched.
a. If the classroom is warm, the crystals may show “warmer” colors without being touched.
2. The crystals aren’t turning the color ranges described on the handout answer key
a. Make sure the structure is in the box on the test layout.
b. Make sure that the test layout is positioned correctly.
c. Make sure the lamp is angled down so that it is aiming at the structure.
d. Make sure the students are checking the thermal crystal color promptly after the light is turned
off.

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Solar Energy Lesson Plan

Page 19

SOLAR ENERGY KIT
Lesson Extender
DURATION
20 Minutes

CONCEPT
How a PV Cell Works

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Rochester Institute of Technology

Solar
 Cell
 Modeling
 Activity
 –15
 Minutes
 
TEAK

Solar Energy Lesson Plan

Page 20

PV CELL INTRODUCTION
Background Information
Photovoltaic cells, or solar cells, capture solar energy and convert that energy into electricity. A PV cell captures
energy by using the energy from the sun’s rays to try and bump an electron off the solar cell. The electron that
was bumped then forces the electrons in front of it to move, causing a chain reaction known as current. A single
cell produces only a small amount of energy, so the cells are usually combines into larger groups known as
panels. Multiple solar panels can then be combined into larger groups called arrays. The ability to change the
number of cells/panels in a grouping allows for the size of the system to be customized.

Simplified Definition


Photovoltaic (PV) Cells
o Photovoltaic cells, or solar cells, capture solar energy and convert that energy into electricity.
o They use the energy from each ray of light to try and bump an electron off the solar cell.
o When the bumped electron moves, it forces the electrons in front of it to move too. This starts a
chain reaction known as current

Group Discussion
(Pose the following questions to the group and let the discussion flow naturally… try to give
positive feedback to each child that contributes to the conversation)

Q: Think back to the PV cell you used earlier. Did you see any moving parts on it?



NO!
The reaction happens inside the cell

Q: Where do you think the electricity is made?



Inside the cell
Layers of materials help to separate the protons from the electrons

Learning Objectives
By the end of this exercise, students should be able to…
• Model and understand how a solar cell, or PV cell, actually works.

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End
 Solar
 Cell
 Modeling
 Activity
 

Solar Energy Lesson Plan

Page 21

Materials





Relatively open area
40 foot rope – white and blue
o 10 knots 2 feet apart (the rest is unknotted)
o Ends knotted together to form a circle
Yellow rope
o Ends knotted together

Procedure
1. Split the students in half.
a. One half will be photons (energy from the sun) in the sun.
b. The other half will be electrons within the photovoltaic cell.
2. Mark out the areas for the sun (yellow rope) and photovoltaic cell (multicolored rope).
3. Have the students stand in their positions along the ropes.
a. The photons will be within the circle representing the sun.
b. The electrons will stand along the knots in the PV cell.
4. Explain the following:
a. A photon will walk and join with the first electron inside the PV cell. This gives the electron
energy and allows it to move.
b. The photon and electron pair move together towards the next electron and then tag them. They
stay at the knot while the second electron goes to the next and tags them. This tagging continues
until the energy reaches the last student on the knotted part of the rope.
c. That student then activates the load on the circuit (rings a bell, or calls out an electric device).
d. Once the bell is rung, have the class chant “Hurray for Solar Energy!”
e. The electron continues to move along the circuit until they reach the first knot (that has been
emptied now).
f. Another photon leaves the Sun and the movements are repeated again (photon and electron pair
up, move down the rope, tag the next electron, tagging continues until bell is rung, electron
travels back to the PV cell, etc)

Activity Extenders



Simulate a cloudy day.
The last electron calls out the name of an electrical device that they are powering. Each device can only
be named once.

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TEAK

Solar Energy Lesson Plan

Page 22

Concluding Discussion
Q: What do you think would happen to the electrons on a cloudy day?


They would move slower because there is less solar energy to push them along

Q: Think of all the electronics you use in your daily activities. Is it possible to use photovoltaic cells to
power some of these? Why or why not? How could this be done?
• Yes, it is possible to use PV cells to power electronics

Q: The PV cell that was used in the first activity only gave off a couple volts of electricity, even in its
optimum operating conditions. How do you think engineers make panels that produce more electricity?
• Make the panels larger
• Combine smaller PV cells to make a large PV panel

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Rochester Institute of Technology

TEAK

Solar Energy Lesson Plan

Page 23

SOLAR ACTIVITY HANDOUT
Solar Panel Positions
Position A: Angled

Position B: Flat

Position C: Vertical

Warm-up Questions
1. Do you think that changing the angle that the solar panel is at will change the amount of voltage it
produces? Why or why not?
_____________________________________________________________________________________
_____________________________________________________________________________________
2. Do you think that covering part of the solar panel will change the amount of voltage it produces? Why or
why not?
_____________________________________________________________________________________
_____________________________________________________________________________________
Data Tables
Solar Panel Box 1
Solar Panel Box 2
Did the numbers light
Did the numbers light
Position
Position
Voltage
up? How much?
up? How much?
A

A

B

B

C

C

Action Table
Action

Did the numbers stay lit? Did they dim?

Cover part of the solar panel
Cover half of the solar panel
Cover all of the solar panel
Did you notice a difference of the clock when the solar panel was moved from Box 1 to Box 2?
___________________________________________________________________________________________
Why do you think the voltage changed when the solar panel position changed?
___________________________________________________________________________________________
What things do you think affect how much electricity is produced by a solar panel?
___________________________________________________________________________________________
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Rochester Institute of Technology

TEAK

Solar Energy Lesson Plan

Page 24

SOLAR ACTIVITY HANDOUT (ANSWERS)
Warm-up Questions
1. Do you think that changing the angle that the solar panel is at will change the amount of voltage it
produces? Why or why not?
Yes, changing the angle will change the voltage. When the solar panel is angled so that its face is
perpendicular to the rays of the sun, it will collect the most rays and therefore produce the most
energy.
2. Do you think that covering part of the solar panel will change the amount of voltage it produces? Why or
why not?
Yes, covering part of the panel will change with amount of voltage. Since the entire surface can
absorb the sun’s rays and change them to current, having less surface area will produce less
electricity. The same thing happens if snow or leaves cover the panel or clouds block the sun.
Solar Panel Box 1
Solar Panel Box 2
Did the numbers light
Did the numbers light
Position
Position
Voltage
up? How much?
up? How much?
Only the time
All of the numbers light Largest
A
A
illuminates
up (looks like 88:88)
voltage
B

Only the time
illuminates

B

All of the numbers light
up (looks like 88:88)

Smaller
voltage

C

Only the time
illuminates

C

All of the numbers light
up (looks like 88:88)

Smaller
voltage

Action

Did the numbers stay lit? Did they dim?

Cover part of the solar panel

The numbers should stay lit

Cover half of the solar panel

The numbers should stay lit

Cover all of the solar panel

The numbers should NOT stay lit

Did you notice a difference of the clock when the solar panel was moved from Box 1 to Box 2?
• In box 1, the clock numbers were illuminated so the time was shown and was easy to read.
• In box 2, the clock numbers were all lit up (so it looks like 88:88) and the time could not be read.
This is because more voltage (electricity) was being produced by the solar panel than the clock
needs to run, causing more than the time to illuminate.
Why do you think the voltage changed when the solar panel position changed?
• The voltage changed because the solar panels are most efficient when the solar rays hit them
perpendicularly (draw a diagram to illustrate).
• When the rays don’t hit that panel straight on, like in positions B & C, the voltage decreases.
What things do you think affect how much electricity is produced by a solar panel?
• The angle the solar panel is positioned at
o Seen by using the multi-meter to measure voltage in the different positions
• The intensity of the sun
o Seen by moving the solar panel from box 1 to box 2
• If the sun is being blocked by anything
o Seen in action table
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TEAK

Solar Energy Lesson Plan

Page 25

KEEPING HEAT IN DESIGN ACTIVITY
Location:
Ruby, Alaska

Time of Year:
Winter

Time of Day:
9:00 am

The Story:
Emmy is a 25 year-old engineer, who has decided to compete in the IDITAROD dogsled race for the first time.
She has gone dog sledding many times but never on her own. The IDITAROD is a very stressful race, and Emmy
is trying to remember everything that she needs to do. On the 13th night of the race, Emmy and her dogs camp out
in the town of Ruby. In the morning, Emmy gets up, packs her gear, and hooks the dogs to the sled. They begin
their journey to the next town, only along the way something goes terribly wrong! Emmy’s dogs come unhooked
and run on without her! Emmy is stranded! The temperature is only 1°F, and Emmy knows she needs a way to
stay warm until someone can come help her. All she has around her is her sled, the supplies she packed, and a
few sticks she can gather from the woods.
Her Supplies:
• A map
• A sandwich bag
• A t-shirt
• An energy bar wrapper
• A tarp
• Sticks
The Challenge:
Use Emmy’s supplies to make a shelter that will keep the cold Arctic snow out, but let the sun warm her up!
Thermal Crystal Data:
Color

Approximate Temp. (°F)

Black

76-77

Red

77-79

Light Green

79-81

Dark Green

81-83

Blue

83-85

Design Tables:
Unprotected Crystal

Color

Material

Color

NOT in the Light
In the Light

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Rochester Institute of Technology

TEAK

Solar Energy Lesson Plan

Page 26

KEEPING HEAT IN DESING ACTIVITY (ANSWERS)
Design Tables:
Unprotected Crystal

Color

NOT in the Light

Black/Light Red

In the Light

Dark Blue

Material

Color

Sandwich Bag

Dark Blue

Tarp

Dark Blue

Sticks

Blue to Black Rainbow

Map

Dark Green/Blue

T-shirt

Red/Light Green

Wrapper

Black/Light Red

Insulated Foil

Black

** Colors of the students thermal crystals may vary based on testing error.

The TEAK Project

 

Rochester Institute of Technology

TEAK

Solar Energy Lesson Plan

Page 27

IMAGE SOURCES
[1] Photovoltaic Cell. 2007. Florida Solar Energy Center. JPEG file.
http://www.fsec.ucf.edu/en/consumer/solar_electricity/basics/how_pv_cells_work.htm
[2] Five Elements of Passive Solar Design. 2013. Energy Trace Webzine. JPEG file.
http://www.energytrace.com/article10-5.htm
[3] PV Solar Panel. 2013. Beijing Shenzhou Guoneng. JPEG file.
http://szgnsolar.com/blog/2013/05/07/pv-solar-panel-serving-vital-role-in-human-life/
[4] Solar Power Molten Salt. 2007. Greener News Word Press. JPEG file.
http://greenernews.files.wordpress.com/2009/07/solar_power_molten_salt.jpg
[5] How a Photovoltaic Cell Processes Sunlight. 2013. ActewAGL. JPEG file.
http://kids.actewagl.com.au/education/energy/RenewableEnergy/SolarEnergy/HowSolarCellsWork.aspx
[6] Darling, David. Active Solar Heating System. 2012. David Darling. JPEG file.
http://www.daviddarling.info/images/active_solar_heating_system.gif
[7] Solar Cell. 2008. Gaszappers. JPEG file.
http://www.gaszappers.com/wp-content/uploads/2008/08/solar_cell.png
[8] Passive Design. 2008. Netspeed Energy Efficient Building Case Studies. JPEG file.
http://www.netspeed.com.au/abeccs/newington/Newington%20Images/passive%20design%20.jpg

The TEAK Project

 

Rochester Institute of Technology

TEAK

Solar Energy Lesson Plan

Page 28

REVISIONS
Date
11/5/2009
 

3/12/2013

Changes Made

Changes Made By

Changed
 activities
 and
 procedures,
 added
 
activity
 and
 instructor
 preparation
 guides,
 
updated
 general
 information
 
Updated formatting. Added table of contents and
work cited page. Fixed grammar and syntax
issues.

The TEAK Project

 

Heather
 Godlewski
 

Todd Jackson

Rochester Institute of Technology

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