Lesson Plan
Course Title: Engineering Design and Problem Solving
Session Title: 3rd Design Project: Solar Power and Solar Water Heating Systems
Performance Objective: After completing this lesson, the students will have demonstrated that
they can apply the engineering design process, their knowledge of solar power and solar water
heating systems, and their knowledge of control and feedback systems to design and build a
solar heating or power system. They will demonstrate their knowledge and skills by presenting
their project to the instructor and the class and by completing the quiz and meeting all of the
criteria in the 3rd Design Project and presentation rubrics.
Specific Objectives:
 Explain how the sun provides Earth with useful energy.
 Explain how the sun's energy can be used to heat water.
 Explain how the sun's energy can used to create electricity, using a Grätzel cell.
 Explain the difference between temperature and heat.
 Identify the features of a system.
 Identify the features of open and closed loop systems.
 Identify the features of a feedback and control system.
 Calculate the efficiency of a process.
 Calculate power used and produced by a system.
 Calculate the rate of heat transfer.
 Practice the design process by designing and building a solar heating or power system.
Preparation
TEKS Correlations:
This lesson, as published, correlates to the following TEKS. Any changes/alterations to the
activities may result in the elimination of any or all of the TEKS listed.
Engineering Design and Problem Solving:
130.373 (c) (1) (A) (B)
. . .demonstrate safe practices during engineering field and laboratory activities; and
. . .make informed choices in the use and conservation of resources, recycling of materials,
and the safe and legal disposal of materials.
130.373 (c) (2) (A) (G) (H)
. . .apply scientific processes and concepts outlined in the Texas Essential Knowledge and
Skills (TEKS) for Biology, Chemistry, or Physics relevant to engineering design problems;
. . .identify the inputs, processes, outputs, control, and feedback associated with open and
closed systems; and
. . .describe the difference between open-loop and closed-loop control systems.
130.373 (c) (3) (A) (B) (C) (D) (E) (F)
. . .communicate visually by sketching and creating technical drawings using established
engineering graphic tools, techniques, and standards;
. . .read and comprehend technical documents, including specifications and procedures;
Copyright © Texas Education Agency 2012. All rights reserved.
1
. . .prepare written documents such as memorandums, emails, design proposals, procedural
directions, letters, and technical reports using the formatting and terminology conventions
of technical documentation;
. . .organize information for visual display and analysis using appropriate formats for various
audiences, including, but not limited to, graphs and tables;
. . .evaluate the quality and relevance of sources and cite appropriately; and
. . .defend a design solution in a presentation.
130.373 (c) (6) (I)
. . .maintain an engineering notebook that chronicles work such as ideas, concepts,
inventions, sketches, and experiments.
Integrated Physics and Chemistry:
112.38 (c) (5) (D) (E) (F) (G) (H) (I)
. . .investigate the law of conservation of energy;
. . .investigate and demonstrate the movement of thermal energy through solids, liquids, and
gases by convection, conduction, and radiation such as in weather, living, and mechanical
systems;
. . .evaluate the transfer of electrical energy in series and parallel circuits and conductive
materials;
. . .explore the characteristics and behaviors of energy transferred by waves, including
acoustic, seismic, light, and waves on water as they superpose on one another, bend
around corners, reflect off surfaces, are absorbed by materials, and change direction when
entering new materials;
. . .analyze energy conversions such as those from radiant, nuclear, and geothermal sources;
fossil fuels such as coal, gas, oil; and the movement of water or wind; and
. . .critique the advantages and disadvantages of various energy sources and their impact on
society and the environment.
Physics:
112.39 (c) (6) (A)
. . .investigate and calculate quantities using the work-energy theorem in various situations;
112.39 (c) (8) (A)
. . .describe the photoelectric effect and the dual nature of light;
Chemistry:
112.35(c) (6) (B) (C)
. . .understand the electromagnetic spectrum and the mathematical relationships between
energy, frequency, and wavelength of light;
. . .calculate the wavelength, frequency, and energy of light using Planck's constant and the
speed of light
112.35(c)(11)(A)(B)
. . .understand energy and its forms, including kinetic, potential, chemical, and thermal
energies;
. . .understand the law of conservation of energy and the processes of heat transfer;
Copyright © Texas Education Agency 2012. All rights reserved.
2
Interdisciplinary Correlations:
Algebra I:
111.32 (b) (1) (A) (B) (C) (D) (E)
. . .describe independent and dependent quantities in functional relationships;
. . .gather and record data and use data sets to determine functional relationships between
quantities;
. . .describe functional relationships for given problem situations and write equations or
inequalities to answer questions arising from the situations;
. . .represent relationships among quantities using concrete models, tables, graphs, diagrams,
verbal descriptions, equations, and inequalities;
. . .interpret and make decisions, predictions, and critical judgments from functional
relationships
111.32 (b) (2) (D)
. . .collect and organize data, make and interpret scatter plots (including recognizing positive,
negative, or no correlation for data approximating linear situations), and model, predict, and
make decisions and critical judgments in problem situations.
Algebra II:
111.33 (a) (4)
. . .Relationship between algebra and geometry. Equations and functions are algebraic tools
that can be used to represent geometric curves and figures; similarly, geometric figures can
illustrate algebraic relationships. Students perceive the connections between algebra and
geometry and use the tools of one to help solve problems in the other.
Geometry:
111.34 (b) (5) (A) (D)
. . .use numeric and geometric patterns to develop algebraic expressions representing
geometric properties;
. . .identify and apply patterns from right triangles to solve meaningful problems, including
special right triangles (45-45-90 and 30-60-90) and triangles whose sides are Pythagorean
triples.
111.34 (b) (8) (D) (F)
. . .find surface areas and volumes of prisms, pyramids, spheres, cones, cylinders, and
composites of these figures in problem situations;
. . .use conversions between measurement systems to solve problems in real-world situations.
Mathematical Models with Applications:
111.36 (c) (1) (A) (B) (C)
. . .compare and analyze various methods for solving a real-life problem;
. . .use multiple approaches (algebraic, graphical, and geometric methods) to solve problems
from a variety of disciplines; and
. . .select a method to solve a problem, defend the method, and justify the reasonableness of
the results.
Copyright © Texas Education Agency 2012. All rights reserved.
3
111.36 (c) (3) (A) (B)
. . .formulate a meaningful question, determine the data needed to answer the question,
gather the appropriate data, analyze the data, and draw reasonable conclusions;
. . .communicate methods used, analyses conducted, and conclusions drawn for a dataanalysis project by written report, visual display, oral report, or multi-media presentation;
111.36 (c) (8) (B) (C)
. . .use trigonometric ratios and functions available through technology to calculate distances
and model periodic motion;
. . .use direct and inverse variation to describe physical laws such as Hook's, Newton's, and
Boyle's laws.
112.33 (5) (A)
. . .observe and record the apparent movement of the Sun and Moon during the day;
112.33 (8) (B) (C)
. . .explain how latitudinal position affects the length of day and night throughout the year;
. . .recognize that the angle of incidence of sunlight determines the concentration of solar
energy received on Earth at a particular location
Earth Science:
112.36 (b) (6) (B) (C)
. . .Energy. The uneven distribution of Earth's internal and external thermal energy is the
driving force for complex, dynamic, and continuous interactions and cycles in Earth's
subsystems. These interactions are responsible for the movement of matter within and
between the subsystems resulting in, for example, plate motions and ocean-atmosphere
circulation.
. . .Relevance. The interacting components of Earth's system change by both natural and
human-influenced processes. Natural processes include hazards such as flooding,
earthquakes, volcanoes, hurricanes, meteorite impacts, and climate change. Some humaninfluenced processes such as pollution and non-sustainable use of Earth's natural
resources may damage Earth's system. Examples include climate change, soil erosion, air
and water pollution, and biodiversity loss. The time scale of these changes and their impact
on human society must be understood to make wise decisions concerning the use of the
land, water, air, and natural resources. Proper stewardship of Earth will prevent
unnecessary degradation and destruction of Earth's subsystems and diminish detrimental
impacts to individuals and society.
Copyright © Texas Education Agency 2012. All rights reserved.
4
O*NET Component
17-2199.11 - Solar Energy Systems Engineers
http://www.onetonline.org/link/summary/17-2199.11
Perform site-specific engineering analysis or evaluation of energy efficiency and solar projects
involving residential, commercial, or industrial customers. Design solar domestic hot water and
space heating systems for new and existing structures, applying knowledge of structural energy
requirements, local climates, solar technology, and thermodynamics.
Tasks:



Design or coordinate design of photovoltaic (PV) or solar thermal systems, including system
components, for residential and commercial buildings.
Create electrical single-line diagrams, panel schedules, or connection diagrams for solar
electric systems using computer-aided design (CAD) software.
Develop design specifications and functional requirements for residential, commercial, or
industrial solar energy systems or components.
Teacher Preparation:
Review the PowerPoint presentation, the quiz, the projects, and the definitions. You may want
to focus your presentation of the lesson’s content primarily on the PowerPoint and the quiz, but
the major goal of this lesson is to have the students actually practice using the engineering
design process (EDP).
References:
Gleue, A. (2008). Creating Your Own Grätzel Solar Cell.
http://teachers.usd497.org/agleue/Gratzel_solar_cell%20assets/instructions%20for%20making
%20the%20gratzel%20cell.htm
World Bank. (2011). World Bank DataBank: World Development Indicators.
http://databank.worldbank.org/ddp/home.do?Step=12&id=4&CNO=2
Videos
Screen 17: Solar Energy Video; from YouTube user; EngineeringTimes
(http://www.youtube.com/watch?v=he_JjrXEfN0)
Screen 18: Grätzel cell Video; from YouTube user; Polytechpress
(http://www.youtube.com/watch?v=ncsNMDgngYI)
Pictures
Slide 10: Renewable Energy Background
Wind turbine: (http://commons.wikimedia.org/wiki/File:Greenpark_wind_turbine_arp.jpg)
public domain
Copyright © Texas Education Agency 2012. All rights reserved.
5
Solar panels: (http://commons.wikimedia.org/wiki/File:SeoulMarineSuncheon052.jpg)
public domain
Slide 11: Sun as an Energy Source (http://commons.wikimedia.org/wiki/File:Sun_in_X-Ray.png)
NASA image, copyright free.
Slide 14: Light Diffraction
Cloud: (http://en.wikipedia.org/wiki/File:Sky_over_Washington_Monument.JPG)
public domain.
Rainbow: Image created by Alpha Graphics for this project.
Slide 15: Light Refraction (http://commons.wikimedia.org/wiki/File:Dispersion_prism.jpg)
public domain.
Slide 16: Photoelectric Effect
((http://upload.wikimedia.org/wikipedia/commons/archive/f/f5/20070507231420%21Photoelectri
c_effect.svg)
Photoelectric effect simulation (http://phet.colorado.edu/en/simulation/photoelectric)
Slide 17: How Solar Photovoltaic Cells Work
http://www.window.state.tx.us/specialrpt/energy/renewable/solar.php
Slide 18: Grätzel cell
http://en.wikipedia.org/wiki/ File:Dye.sensitized.solar.cells.jpg
Slide 24: Earth as Thermodynamic System http://www.nasa.gov/audience/forstudents/58/features/F_The_Role_of_Clouds.html
Slide 27: Solar Water Heating System
http://commons.wikimedia.org/wiki/File:Calefon_solar_termosifonico_compacto.jpg
Slide 28-29: Open Loop Systems
http://commons.wikimedia.org/wiki/File:Active_open_loop_solar_HW_system.gif
Slide 29: Closed Loop Systems
http://commons.wikimedia.org/wiki/File:Active_closed_loop_solar_HW_system.gif
Slide 30-31: Feedback and Control Systems
Images created by Alpha Graphics for this project.
Instructional Aids:
Useful Resources:
Solar energy timeline: http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf
Grätzel cell information: http://www.ph.utexas.edu/~igert/Nanolab_Experiment.pdf or
http://www.teachengineering.org/view_activity.php?url=collection/uoh_/activities/uoh_organic/uo
h_organic_activity1.xml
Rate of heat transfer: http://www.physicsclassroom.com/class/thermalP/u18l1f.cfm
Copyright © Texas Education Agency 2012. All rights reserved.
6
Simulations:
Blackbody spectrum simulation: http://phet.colorado.edu/en/simulation/blackbody-spectrum
Photoelectric effect simulation: http://phet.colorado.edu/en/simulation/photoelectric
Gas properties simulation: http://phet.colorado.edu/en/simulation/gas-properties
Social Media:
Solar energy video: http://www.youtube.com/watch?v=he_JjrXEfN0
Grätzel Cell video: http://www.youtube.com/watch?v=ncsNMDgngYI
Materials Needed:
Instructor Equipment Required:
Computer (1)
Projector (1)
Desk lamp (1)
Heat lamp (1)
Sun light
Prism (one as a demonstration, or several to pass around to students)
Gloves (set a good example to your students by using proper safety equipment)
Goggles (set a good example to your students by using proper safety equipment)
Volt meter (1)
Graduated cylinder (1)
Battery operated pump (1)
The following materials will be required if the Grätzel cell will be built as an instructor
demonstration rather than a student project. Otherwise, these are student materials and
the amounts should be increased based on the number of students and/or groups:
Grätzel Cells:
Conducting glass plates (tin-oxide coated) (2)
Titanium Dioxide Paste (4 grams)
Iodide electrolyte (3 mL)
Small binder Clips (2)
Graphite pencil (HB woodless graphite pencil, can be purchased at an art supply store, 1 per
group or one can be shared among the groups)
(Alternative to above is to purchase Grätzel Cell kit. One such kit can be found at this link:
http://ice.chem.wisc.edu/Catalog/SciKits.html#Anchor-Nanocrystalline-41703) Additionally, the
following materials are required:
Distilled water (a few drops)
Raspberries (3-4)
Blackberries (3-4)
Chlorophyll (can be purchased at a dietary supplement store) (1 fl oz)
Paper towels (small roll)
Copyright © Texas Education Agency 2012. All rights reserved.
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Student Materials Needed:
The following materials will be needed if the Grätzel cell will be built by students in teams
of 2-3 students. The amounts shown are enough for 5 groups to each build one Grätzel
cell.
Grätzel cells:
Conducting glass plates (tin-oxide coated) (10 total, 2 per group)
Titanium dioxide paste (20 grams, 4 grams per group)
Iodide electrolyte (15 mL, 3 mL per group)
Small binder clips (10 total, 2 per group)
Graphite pencil (HB woodless graphite pencil, can be purchased at an art supply store) (5 total,
or 1 can be shared among the groups)
(Alternative to above is to purchase Grätzel cell kit. One such kit can be found at this link:
http://ice.chem.wisc.edu/Catalog/SciKits.html#Anchor-Nanocrystalline-41703).
Additionally, the following materials are required:
Distilled water (1 L)
Raspberries (20 total, 4 per group)
Blackberries (20 total, 4 per group)
Chlorophyll (can be purchased at a dietary supplement store) (5 fl oz, 1 fl oz per group)
Paper towels (small roll)
Wire (optional, only if you are testing the power by some other means than the volt meter, about
ten inches per group)
Volt meter (5 total, one per group, or one can be shared among the groups)
Gloves (one pair per student)
Goggles (one pair per student)
Engineering notebooks (provided by students)
Solar water heaters (open or closed loop):
The amounts shown are enough for five groups to each build one intermediate level solar
water heater. (For additional advanced level project, see the materials listed at the end of
this section).
Black flexible tubing with an inner radius of an inch or more (15-25 feet total, or 3-5 feet per
group)
Cardboard (10 – 8x10 pieces, or 2 – 8x10 pieces per group, or can have students bring in
empty cereal boxes)
Scissors (1 pair per group)
Zip ties (20-30 total, or 4-6 per group, 6”-8” ties work best)
Antifreeze (1 ½ gallons total, or 1 quart per group)
Funnels (5 total, or 1 per group, or one can be shared among the groups)
Small bucket or tub (5 total, or 1 per group)
Aluminum foil (1 roll)
Battery operated pump (5 total, or one per group)
Copyright © Texas Education Agency 2012. All rights reserved.
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Measuring the rate of heat transfer:
The amounts shown are enough for five groups to each measure the rate of heat transfer
of the provided data set as well as of their own group’s solar water heater.
Graduated cylinder (1 can be shared among the groups)
Battery operated pump (5 total, or 1 per group)
Thermometer (5 total, or 1 per group)
Heat transfer data set (included in the handout)
Engineering notebooks (provided by students)
Pens (one per student)
Advanced (feedback and control loop) system:
The amounts shown are enough for one group to build the advanced design project in
addition to the intermediate level project listed above.
Soldering iron (1)
Solder (small roll)
Wire (2-3 feet)
Servos (may be borrowed from your school’s robotics team, or purchase from an electronics
store)
Heating element (1)
Waterproof temperature sensor (1)
Resistors (varying resistances)
Switches (2)
PIC controllers (2)
Learner Preparation:
A basic knowledge of the physics of light, heat, and electricity would be useful for this activity. A
working knowledge of systems and feedback and control loops would also be useful.
Introduction
Introduction (LSI Quadrant I):
SAY: Today we are going to look at the topic of our third design project: solar power and solar
water heating systems.
ASK: How many of you have heard of or seen solar power panels or solar water heating
panels? Raise your hand, if you have heard of either of these systems before.
SHOW: Pictures of solar power panels and solar water heating panels
SAY: We are going to explore how these systems work and are designed. Then, we are going
to have an opportunity to design, develop, and evaluate our own solar systems.
ASK: How do solar systems relate to the other systems we have discussed?
SHOW: Images or video of solar power systems
Copyright © Texas Education Agency 2012. All rights reserved.
9
Outline
Outline (LSI Quadrant II):
Instructors can use the PowerPoint presentation, slides, handouts, and note pages in
conjunction with the following outline.
Class
Period(s)
Topic(s)
Assignment
1-2
• The Engineering Design Process- Quick
Review
• Student Background about Need for Solar
Energy
• Vocabulary
#1-Individual; Handout, Vocabulary Work
3-4
• Solar Energy Background and History
• Calculate Home Power Usage
#2-Individual; Solar Energy Timeline Reading Packet
Handout and Worksheet
5-10
• Grätzel Cell Introduction and Team Project
#3-In teams of 2-3; Apply the engineering design process
to the scenario given; complete the “Mini Engineering
Notebook” (Daily)
11-30
• Intermediate Open or Closed Loop Solar
Water Heating System or Advanced
Feedback Control Design System
• Background and Team Project
#4-In teams of 2-3; Apply the engineering design process
to the scenario given; complete the “Mini Engineering
Notebook” (Daily)
MI
Outline
Introduction: 1 class period
PPT presentation: 2-3 class periods
Activity: 22-25 class periods
Quiz: 0.5 class period
Notes to Instructor
Introduction – 2-4
days (45 minutes per
class period)
 Introduction and
background
 What is solar
energy?
 Why do we need
solar energy?
 Types of solar
systems
 Solar energy
handouts
Activities – 25 days
(45 minutes per day)
 Team projects
 Team
Copyright © Texas Education Agency 2012. All rights reserved.
10
presentations
PART 1: SOLAR ELECTRICITY
Required Materials:
Teaching Suggestion: Complete this design project
in two parts. First, for Part 1, spend days 1-2 focusing
on the solar electricity portion of the PowerPoint.
Then, spend days 3-10 building the Grätzel cells.
The second part of the design project is focused on
solar water heating systems. Save the second half of
the PowerPoint presentation until you are ready to
start having the students work on designing the solar
water heating systems. For Part 2, spend 1-2 days
on the PowerPoint and about 15-20 days designing
the solar water heating systems and facilitating the
student presentations.
US Department of
Energy “The History of
Solar” PDF handout.
Provide each student
with a copy of the
handout or link so they
can download the
handout:
http://www1.eere.ener
gy.gov/solar/pdfs/solar
_timeline.pdf
I. Solar Power Presentation
Have students review the “History of Solar” handout
and have a class discussion about the use of solar
energy throughout history.
Suggested Materials:
U.S.D.O.E. history of
solar questions
handout
Life on Earth is supported by the Sun.
As the Earth orbits the Sun, the position of the Sun in
the sky changes.
II. Solar Energy Background and Scenario
Required Materials:
Background about lack of electricity in rural areas
especially in developing countries
3rd Design Project
PowerPoint
(Slides 6 – 20)
Introduce student scenario.
Suggested Materials:
Project design
background scenario
student handout
II. Light and its Properties
Suggested Materials:
Brief introduction to light and its properties
Use the desk or heat
lamp to demonstrate
that light is energy by
having the students
feel the heat that the
light gives off.
Sunlight (or white light) is made up many colors of
light that we can see and not see (Electromagnetic
Spectrum).
We can calculate the energy of the light by using its
Copyright © Texas Education Agency 2012. All rights reserved.
11
wave characteristics speed (c), frequency (ν), and
wavelength (λ). c =λν
Light is both a particle and a wave.
We know this because of diffraction, refraction, and
the photoelectric effect.
When light is absorbed by the solar panel (or
anything), it acts as a particle.
Use the prism to
demonstrate that white
light is made up of
many colors of light. If
you would like you can
shine a
monochromatic light
source through the
prism to demonstrate
the difference.
Emphasize that there
is an inverse
mathematical
relationship between
frequency and
wavelength.
Use this simulation to
show how the radiation
spectrum of objects
changes with
temperature
http://phet.colorado.ed
u/en/simulation/blackb
ody-spectrum.
Use this simulation to
help demonstrate the
photoelectric effect
and the particle nature
of light
http://phet.colorado.ed
u/en/simulation/photoe
lectric.
III. General Solar Cells
Suggested Materials:
When sunlight hits certain types of materials, the
wavelengths of light have enough energy to cause
electrons to be ejected.
Use the solar energy
YouTube video to help
explain how solar
panels work and how
they provide useful
energy
http://www.youtube.co
m/watch?v=he_JjrXEf
A photovoltaic (or solar) cell is set up to collect the
ejected electrons and move them into a circuit where
they can do useful work.
Copyright © Texas Education Agency 2012. All rights reserved.
12
Because the Sun is not always in the same position in
the sky, the amount of sun that reaches a stationary
panel changes throughout the day.
To maximize the electrical power produced, solar
panel systems sometimes use a feedback and control
loop that adjusts the angle of the solar panel.
N0.
Use the photoelectric
simulation to help
explain how exposing
the panel to more
direct sunlight
increasing the
electrical power
produced
http://phet.colorado.ed
u/en/simulation/photoe
lectric.
IV. Grätzel Solar Cells
Suggested Materials:
Grätzel cells are low cost solar cells that use dyes to
absorb sun light into the cell and transfer the energy
using electrochemical reactions. A Grätzel cell is
made from a porous layer of titanium dioxide nanoparticles that is covered with a dye that absorbs
sunlight, like the chlorophyll in plant leaves.
Use the Grätzel cell
YouTube video to help
explain the history of
the Grätzel cell, and
the potential it has to
revolutionize how we
use solar
http://www.youtube.co
m/watch?v=ncsNMDg
ngYI.
The titanium dioxide-dye layer is covered in an
electrolyte solution. A platinum-based catalyst is
placed above the electrolyte solution.
Just as in a traditional battery titanium dioxide acts as
the anode, the platinum acts the cathode, and the
electrolyte acts as the conducting material in
between.
The dye collects the light particle (photon) and
releases an electron which then goes into the titanium
dioxide. The electrons then go into an external circuit
to do work and then returns to the cathode (platinum)
where it passes through the electrolyte back into the
dye.
Suggested Review:
Walk your students
through how a Grätzel
cell works. Connect
the photosensitivity of
the plant-based dyes
to photosynthesis.
V. Electricity and Power
Suggested Materials:
Current is the flow of electrons through a circuit.
As they are abstract
and often hard to
understand concepts,
use the waterfall
analogy to help explain
current and voltage.
Voltage is the potential difference that causes the
electrons to move.
The electrical power generated by solar cell can be
found by using Joule’s law. Joule’s law:
As an example, show
Copyright © Texas Education Agency 2012. All rights reserved.
13
P = electrical power = current × voltage = I × V
Where the current is given in amps (A), the voltage is
given in volts (V), and the power is reported in watts
(W).
You can use a volt meter to measure the current and
voltage produced by the solar cell. Then, multiply
them together to find the power.
two different images of
bridal veil falls in
Yosemite National
park at a high flow
(high current) and low
flow (low current). The
height of the falls stays
the same, so the
voltage is the same
but the current is
changing. When you
discuss power you can
refer to these images
again. The low flow
waterfall has less
power because the
current, I, is smaller.
When discussing
Joule’s law,
emphasize that there
is a direct
mathematical
relationship between V
and P as well as I and
P, and an inverse
mathematical
relationship between V
and I.
VI. Efficiency of Solar Cells
Suggested Review:
In science and engineering, efficiency is defined as
the work done divided by the energy used to do that
W
work ( ).
Help the students
calculate the power of
the example cell.
E
You can calculate the efficiency of a solar cell by
measuring the power of the incident light (Pin) and
measuring the subsequent output power of the solar
P
cell (Pout). Then divide the Pout by Pin, ( Pout ).
in
When measuring the
actual efficiency of a
solar cell, you use the
maximum power point
for the solar cell. This
involves using an
adjustable resistor to
find the resistive load
that maximizes V × I. If
you have students that
are more advanced,
introduce this
procedure.
Copyright © Texas Education Agency 2012. All rights reserved.
14
Discuss the efficiency
chart with your
students. Find dyesensitized cells
(Grätzel cells) and
discuss with your
students how their
efficiency compares
with that of the silicon
based solar cells.
What advantages do
Grätzel cells have that
make them a viable
product?
VII. Exercise: Calculate Home Power Usage
Required Homework:
Have students bring in power bills from home.
Have students bring in
power bills from home.
(Have some extra
example bills on hand
in case some students
cannot get a copy of
their own.)
Discuss the units of power used in their bills (kilowatts
per hour).
Have them use the monthly amounts to calculate how
much power they use in a day.
Discuss how this relates to the typical output from a
solar cell.
Suggested Materials:
Home energy usage
analysis handout
VIII. Activity: Grätzel Cell Development
Required Materials:
Using the Grätzel cell kit, have your students
construct Grätzel cells using different plant based
dyes: chlorophyll, blackberries, and raspberries.
Grätzel cell handout;
see the Grätzel cell
materials list in the
materials section
above. Either the
instructor can build
one Grätzel cell as a
demonstration, or
groups of 2-3 students
can each create their
own Grätzel cells.
Use a volt meter to measure the voltage and current
produced with each dye when exposed to a broadspectrum light or sunlight as the light source. Have
your student record data for each dye-based cell.
Using the standard sunlight power per unit area of 0.1
W/cm2, calculate the efficiency of each type of dyebased solar cell and determine which dye is the most
effective.
Use the Grätzel cell
PDF presentation or
the materials provided
Copyright © Texas Education Agency 2012. All rights reserved.
15
with the kit to help you
and your student
assemble the Grätzel
cells.
To do this activity in
one day, pre-load the
glass plates with
titanium dioxide.
If you have time, have
your students build a
panel out of their solar
cells. Connect them in
parallel and in series
and discuss with your
students how this
changes the results.
Copyright © Texas Education Agency 2012. All rights reserved.
16
PART 2: SOLAR WATER HEATING
Required Materials:
Teaching Suggestion: Show the second half of the
PowerPoint presentation for the first two days and
then have students work on designing the solar water
heating systems for 15-20 days.
3rd Design Project
PowerPoint
(Slides 21 – 30)
Suggested Materials:
IX. Thermodynamic Systems
Overview of thermodynamic systems and variables
pressure, temperature, volume and amount of
material
Earth as an open thermodynamic system with internal
and external energy
Use the following
simulations to help you
describe what a
thermodynamic
system is:
http://phet.colorado.ed
u/en/simulation/statesof-matter-basics
Sun as the input energy
http://phet.colorado.ed
u/en/simulation/gasproperties
Connect the concept
of the earth as a
system to the other
types of systems your
students have
reviewed in this unit.
X. Temperature and Heat
Suggested Materials:
Temperature
Use these simulations
to help you describe
the difference between
temperature and heat:
http://phet.colorado.ed
u/en/simulation/blackb
ody-spectrum
Thermal energy, heat and heat transfer via molecular
collisions
Review of light as energy and the absorption of light
as the transfer of thermal energy
http://phet.colorado.ed
u/en/simulation/gasproperties
When reviewing light
as an energy source,
have your students
recall what they
Copyright © Texas Education Agency 2012. All rights reserved.
17
learned in the solar
power lessons and
activity.
XI. Solar Heating
Required Materials:
Brief background on solar heating
Student solar water
heater handout
Open and closed solar heating systems
XII. Feedback and Control Loops
Suggested Review:
Review feedback and control loops. Discuss use of
feedback and control loops to make sure the solar
heater is heating the water to the correct temperature.
Discuss rate of energy transfer in solar heaters.
Review what you have
already covered in
feedback and control
loops and connect it to
the open and closed
loop solar water
heating examples
provided.
XIII. Exercise: Rate of Heat Transfer
Required Materials:
Using a supplied data set, have your students
calculate and graph the rate of thermal energy
transferred to water in a solar heater.
Student Solar Water
Heater Handout with
provided data set.
Discuss use of feedback and control loops to adjust
the angle of a solar panel to follow the sun.
Suggested Review:
For more information
on the experiment
review the paper:
J. Razavi, M.R. Riazi,
M. Mahmoodi."Rate of
heat transfer in
polypropylene tubes in
solar water heaters,"
Solar Energy, Vol. 74,
Issue 6, June 2003,
Pages 441-445.
XIV. Activity: Solar Water Heater Design
Required Materials:
Suggestion: This project has two options. Students
can either design an intermediate open or closed loop
See materials list in
the materials section
Copyright © Texas Education Agency 2012. All rights reserved.
18
solar water heater, or they can design an advanced
system which has all the elements of the first design,
but also incorporates a feedback control design.
above for open and
closed loop solar water
heater systems.
Have your students design and build an open or
closed solar water heater.
For both systems
students will need a
pump to move the
water or antifreeze
around. Because of
the timescale and
location of this activity
this should be done
with a battery operated
pump.
Have them test their system, using the sun (or a heat
lamp) and a thermometer.
Find the rate of heat transfer.
Have your student explain why they chose the system
they did.
Use the graduated
cylinder to make sure
every group is heating
the same amount of
water (or at the
minimum they know
how much water they
are heating)
To build the solar
water heaters line the
cardboard with
aluminum foil and cut
holes to zip tie the
tubing to the
cardboard. Then
assemble the system.
Make sure the tub of
water is shaded and
covered if the
experiment is done
outside. For a closed
loop system, make
sure you load the
antifreeze before you
coil the tubing onto the
panel.
XV. Solar Water Heater with Feedback Control
Design
For an advanced design project, have your students
choose one of the following feedback and control
design projects:
Required Materials:
If you choose to have
students work on the
advanced design
project with a feedback
Copyright © Texas Education Agency 2012. All rights reserved.
19
Design and develop a solar heating system that uses
a feedback and control loop to switch between
heating water with a solar heater and an electric
element when the temperature in the solar water
system drops below 120˚F.
Design and develop a solar panel system that uses a
feedback and control loop to change the angle of the
panel when the power output of the solar cell drops
below a level that you determine is too low.
control, see the
required materials list
in the materials section
above.
It is recommended that
the students work in
teams to work on this
project. They should
use, and improve
upon, their solar power
and solar heater
designs developed in
this lesson.
As a part of their
deliverables, students
must provide their
engineering design
drawings for the
system and discussed
how the plan changed
as they built the
system.
To build a working
system, students will
need some circuit
design experience and
supplies. You can
require that the system
work or simply be a
model depending on
your student’s skill
level and your access
to materials.
Students should be
able to describe how
their system works
regardless of whether
it is a working model or
not.
Groups that are
working on the solar
water heater should
experiment with other
materials for the tubing
and heating fluid.
Copyright © Texas Education Agency 2012. All rights reserved.
20
Verbal
Linguistic
Logical
Mathematical
Visual
Spatial
Musical
Rhythmic
Bodily
Kinesthetic
Intrapersonal
Interpersonal
Naturalist
Existentialist
Application
Guided Practice (LSI Quadrant III):
Work with your students on how to measure and calculate efficiency of solar cells and the heat
transfer rate for a solar heater. Also work with them on their estimations of daily power use in
their homes.
Independent Practice (LSI Quadrant III):
Test the performance of Grätzel cells constructed using different plant based dyes: chlorophyll,
blackberries, and raspberries.
Design, build, and test an open or closed solar water heater. For an advanced design project,
have your students choose one of the following feedback and control design projects:
Design and develop a solar heating system that uses a feedback and control loop to switch
between heating water with a solar heater and an electric element when the temperature in the
solar water system drops below 120˚F.
Design and develop a solar panel system that uses a feedback and control loop to change the
angle of the panel when the power output of the solar cell drops below a level that you
determine is too low.
Summary
Review (LSI Quadrants I and IV):
Question: How does a Grätzel solar cell work?
Answer: The plant dye absorbs the photons in the sunlight and releases electrons into the
titanium dioxide. The electrons then travel via the conducting glass plate into the circuit
connected to the panel. The circuit is completed by electrons returning to the opposite glass
plate and traveling through the electrolyte back to the dye.
Question: What is the difference between an open loop and a closed loop solar water heating
system?
Answer: Water in an open loop solar water heating system is heated directly by the sun. In a
closed loop system a fluid, such as glycol, is heated by the sun and then the fluid heats the
water in the tank through conduction.
Copyright © Texas Education Agency 2012. All rights reserved.
21
Evaluation
Informal Assessment (LSI Quadrant III):
Attentiveness in class, note taking, questions, sample drawings. Option to use the design
process rubric in a simplified form to assess preliminary drawings.
Formal Assessment (LSI Quadrant III, IV):
The design process quiz, a formal evaluation of student design process practice using the rubric
(first in a simplified form for simple sketch practice, then more completely as needed for more
detailed drawings and student practice on the full design process).
Extension
Extension/Enrichment (LSI Quadrant IV):
When measuring the actual efficiency of a solar cell you use the maximum power point for the
solar cell. This involves using an adjustable resistor to find the resistive load that maximizes V x
I. If you have students that are more advanced, especially in electronics, introduce this
procedure for them to use when finding the efficiencies of their solar cells.
Copyright © Texas Education Agency 2012. All rights reserved.
22
3rd Design Project Definitions
•
Black Body Radiation: the electromagnetic radiation that would be radiated from an
ideal black body; the distribution of energy in the radiated spectrum of a black body
depends only on temperature and is determined by Planck's radiation law
•
Current: a flow of electricity through a conductor
•
Diffraction: change in the directions and intensities of a group of waves after passing by
an obstacle whose size is approximately the same as the wavelength of the waves
•
Efficiency: a dimensionless performance measure of a device, energy input divided by
work output
•
Electrical Power: the product of voltage and current
•
Electrolyte: A liquid or gel that contains ions and can be decomposed by electrolysis,
e.g., electrolytes that are present in a battery
•
Electromagnetic Radiation: a kind of radiation including visible light, radio waves,
gamma rays, and X-rays, in which electric and magnetic fields vary simultaneously
•
Electromagnetic Spectrum: the range of wavelengths or frequencies over which
electromagnetic radiation extends
•
Frequency: number of crests or troughs of a wave that pass a given point in a specified
period of time, usually 1 second
•
Heat: the transfer of energy from one body to another as a result of a difference in
temperature
•
Heat Conduction: the transfer of thermal energy between neighboring molecules in a
substance due to a temperature gradient
•
Heat Convection: heat transfer in a gas or liquid by the circulation of currents from one
region to another
•
Heat Radiation: thermal radiation is electromagnetic radiation emitted from a material
which is due to the heat of the material
•
Kinetic Energy: energy that a body possesses by virtue of being in motion
•
Particle-Wave Duality: the property of matter and electromagnetic radiation that is
characterized by the fact that some properties can be explained best by wave theory and
others by particle theory
•
Photoelectric Effect: the effect that causes electrons are emitted from matter (metals
and non-metallic solids, liquids or gases) as a consequence of their absorption of energy
from electromagnetic radiation of very short wavelength, such as visible or ultraviolet
light
Copyright © Texas Education Agency 2012. All rights reserved.
23
3rd Design Project Definitions, cont.
•
Photon: a particle representing a quantum of light or other electromagnetic radiation
•
Photosensitive: having chemical, electrical, or other response to light
•
Photovoltaic: producing a voltage when exposed to radiant energy (especially light)
•
Refraction: refraction is the change in direction of a wave due to a change in its speed
•
Solar Cell: a cell that converts solar energy into electrical energy
•
Solar Power: power obtained by harnessing the energy of the Sun's rays
•
Solar Water Heater: a water heater that makes direct use of solar energy
•
Temperature: the degree or intensity of heat present in a substance or object,
especially as expressed according to a comparative scale and shown by a thermometer
or perceived by touch
•
Thermal Energy: the internal energy of an object due to the kinetic energy of its atoms
and/or molecules
•
Volt meter: a voltmeter is an instrument used for measuring the electrical potential
difference between two points in an electric circuit
•
Voltage: an electromotive force or potential difference expressed in volts
•
Wavelength: the distance between successive crests of a wave, particularly points in a
sound wave or electromagnetic wave
Copyright © Texas Education Agency 2012. All rights reserved.
24
3rd Design Project Handout for the US DOE’s History of Solar
(Page 1 of 2)
Name_________________________________
Date__________________________________
Directions: After reviewing the U.S. Department of Energy’s The History of Solar
handout at http://www1.eere.energy.gov/solar/pdfs/solar_timeline.pdf , answer the
questions or provide the requested information. Use proper spelling and grammar
throughout your work. (5 points per correct answer)
1. For what purpose was solar energy first used in the 7th century?
2. How was solar energy used in times of war by the Greeks?
3. When was solar cooking begun? Who was given credit for building the first solar
collector? Who was the first person to cook with the solar collector?
4. What is the significance of selenium in solar energy collection?
5. What was the first satellite powered by a photovoltaic (PV) array? When did this
usage of PV technology in space occur?
Copyright © Texas Education Agency 2012. All rights reserved.
25
3rd Design Project Handout for the US DOE’s History of Solar
(Page 2 of 2)
6. Explain what the NREL is and its significance to solar technology development.
7. Which year had the most events that impacted solar energy development and
wider acceptance? Defend your answer with information from the handout.
8. How has NASA’s use furthered society’s acceptance of solar technology?
9. Based on this article, what state has embraced solar technology?
10. Based on what you read in the section titled “The Expected Future Direction of
Solar Technology,” what do you think is most important in regards to the future of
solar technology? Explain and defend your answer.
Copyright © Texas Education Agency 2012. All rights reserved.
26
3rd Design Project Student Home Energy Usage Analysis Handout
(Page 1 of 1)
Name_________________________________
Date__________________________________
Directions: After reviewing a home energy bill, complete all the research and
information gathering work using the reading and information shared in class.
Home Square Footage___________
Date of Bill___________
A. Kilowatt Hour Usage Information
Month
Notes
B. Generation and Transmission Charges
Month
Quantity
Rate
Notes
C. Use the monthly amounts to calculate how much power the household
members use in a day.
D. Explain how this information relates to the typical output from a Solar cell.
Copyright © Texas Education Agency 2012. All rights reserved.
27
3rd Design Project Student Background and Scenario Handout
(Page 1 of 2)
Name_________________________________
Date__________________________________
Directions
After reading the background information and scenario, complete all the design and
building assignments using the engineering design process. See the project rubric for
specific grading requirements for all these components.
Background
Many areas throughout the world face serious limitations due to a lack of energy
resources and the subsequent related issues, such as lack of adequate sanitation,
healthcare provisions, and clean water sources. Specifically, people in developing
countries regularly encounter limited energy resources and accompanying
circumstances. Of particular concern is the lack of electricity in rural areas. There is a
crucial need to alleviate this lack of reliable electricity in order to improve residents’
health conditions, social exchanges, and economic stability. For example, rural areas in
the United States, Mexico, Africa, India, and China face significant problems meeting
electricity demand with current supply lines. Demand is increasing exponentially
compared to the supply. According to the World Bank’s World Development Indicators
(WDI), approximately 50 percent of rural residences in developing countries, such as
India and Africa, are currently without electricity. In addition, rolling brownouts and
complete electrical blackouts are a common occurrence throughout many countries’
rural areas and major cities.
The World Bank’s DataBank also reports that unreliable electricity is one of the primary
obstructions to economic development and stability for residents in many developing
areas. In addition, coal shortages worldwide are further straining power generation
capabilities in many rural areas. In order to meet the public demand for electricity, a
number of options are possible. Power generation using the readily accessible solar
energy is one possibility. Many rural areas have rich solar energy resources. For
example, the average solar radiation intensity in parts of the southwestern United States
is 200 MW/km square (megawatt per kilometer square). Thus, these areas have a vast
potential for renewable energy sources, especially in potential solar power. Other areas
have similar potential to capitalize on this sustainable renewable natural resource.
Countries should support their solar energy industries, since the current political and
economic climates are favorable, there is a high dependence on foreign oil, there is an
opportunity for innovation in solar cell creation, and demand. Another possible solution
to develop the solar market is to set up, or stimulate, new solar funds to guarantee
project financing.
Copyright © Texas Education Agency 2012. All rights reserved.
28
3rd Design Project Student Background and Scenario Handout
(Page 2 of 2)
Student Scenario
Imagine that you have been relocated to a rural area in which you have limited access
to electricity on the normal utility grid. You need to have regular electricity to conduct
business, stay in contact with friends and family members, and have a reliable potable
and hot water source. You have to present your idea to a local zoning board and your
company in order to get the funding and clearances for your systems, so you don’t have
to pay the costs yourself.
Student Assignments
In the process of creating feasible systems to demonstrate, you will
1. follow the engineering design process (EDP),
2. build a Grätzel cell solar system and test it using different colored dyes,
3. calculate your home’s electricity usage, based on your family’s utility bill,
4. calculate the heat transfer of a solar water heater system,
5. build an open or closed loop solar water heater system,
6. build a feedback control loop system solar hot water heater,
7. create a presentation about your Grätzel cell and solar hot water heater systems,
documenting the steps of the engineering design process (EDP) for the general
public and the board members, and
8. describe and defend how and why you should receive funding to create these
solar power and solar water heating systems.
Copyright © Texas Education Agency 2012. All rights reserved.
29
3rd Design Project Student Grätzel Cell Handout
(Page 1 of 2)
Name_________________________________
Date__________________________________
Directions: After reading the background information and scenario, use the engineering
design Process and create Grätzel cells in teams. See the project rubric for specific grading
requirements for each component.
Materials Needed:
1. Conducting glass plates (tin-oxide coated) (2 per group)
2. Titanium dioxide paste (4 grams per group)
3. Iodide electrolyte (3 mL per group)
4. Small binder clips (2 per group)
5. Graphite pencil (HB woodless, 1 per group, or share among the groups)
6. Distilled water (1 L)
7. Raspberries (4 per group)
8. Blackberries (4 per group)
9. Chlorophyll (1 fl oz per group)
10. Paper towels (1 roll per class)
11. Sunlight, heat lamp, or desk lamp (1 lamp per group)
12. Volt meter (1 per group, or share among the groups)
13. Gloves (one pair per student)
14. Goggles (one pair per student)
15. Engineering notebook (provided by students)
16. Pens (1 per student)
Creation of Grätzel Solar Cells
Grätzel solar cells are low cost solar cells that use dyes to absorb sun light into the cell and
transfer the energy using electrochemical reactions. A Grätzel cell is made from a porous layer
of titanium dioxide nano-particles that is covered with a dye that absorbs sunlight, like the
chlorophyll in plant leaves. The titanium dioxide-dye layer is covered in an electrolyte solution.
A platinum-based catalyst is placed above the electrolyte solution. Just as in a traditional
battery, titanium dioxide acts as the anode, the platinum acts the cathode, and the electrolyte
act as the conducting material in between the two. The dye collects the light particle (photon)
and releases an electron, which then goes into the titanium dioxide. The electrons then go into
an external circuit to do work and then returns to the cathode (platinum), where it passes
through the electrolyte back into the dye. View the Grätzel cell YouTube video at
http://www.youtube.com/watch?v=ncsNMDgngYI to learn more about the history of the Grätzel
cell, and the potential it has to revolutionize how we use solar.
Copyright © Texas Education Agency 2012. All rights reserved.
30
3rd Design Project Student Grätzel Cell Handout
(Page 2 of 2)
1. After viewing the video, explain how a Grätzel cell works.
2. Correlate the photosensitivity of the plant-based dyes in a Grätzel cell to photosynthesis.
3. In groups of 2-3 students, design and create your Grätzel cell, as instructed by your
teacher.

Using the Grätzel cell materials and equipment, construct Grätzel cells using
different plant based dyes: chlorophyll, blackberries, and raspberries.

Use a volt meter to measure the voltage and current produced with each dye,
when exposed to a broad-spectrum light or sunlight as the light source. Record
data for each dye-based cell.

Using the standard sunlight power per unit area of 0.1 W/cm2, calculate the
efficiency of each type of dye-based solar cell and determine which dye is the
most effective.
Copyright © Texas Education Agency 2012. All rights reserved.
31
3rd Design Project Student Solar Water Heater Handout
(Page 1 of 2)
Name_________________________________
Date__________________________________
Practice: Calculate the rate of heat transfer to the water in the following sample data set.
Assume that h is equal to 13 W/m2/C° and A is equal to 59,420 cm2.
Table 1. Set of experimental data.
Experiment Tin (° C)
Tout (° C)
1
19
25.7
2
19
27.4
3
19
31.1
4
19
32.0
5
19
38.2
6
19
44.4
7
19
50.0
Rate of heat transfer:
Q = h x A x (Tin – Tout)
Directions: After reading the background information and scenario, create solar water heating
systems in teams. See the project rubric for specific grading requirements for each component.
Materials Needed:
1. Black flexible tubing with an inner radius of an inch or more (3-5 feet per group)
2. Cardboard (2 – 8x10 pieces per group, or bring in empty cereal boxes if your instructor
asks you to do so)
3. Scissors (1 pair per group)
4. Zip ties (4-6 per group, 6”-8” ties work best)
5. Antifreeze (optional: can use water or another type of fluid instead, 1 quart per group
only if designing the closed loop system)
6. Funnels (1 per group, or one can be shared among the groups)
7. Small bucket or tub (1 per group)
8. Aluminum foil (1 roll per class)
Equipment Needed:
1.
2.
3.
4.
5.
6.
7.
8.
Graduated cylinder (1 per class)
Sunlight or heat lamp (1 per group)
Thermometer (1 per group, or share among the groups)
Battery operated pump (1 per group)
Gloves (1 pair per student)
Goggles (1 pair per student)
Engineering notebook (provided by students)
Pens (1 per student)
Copyright © Texas Education Agency 2012. All rights reserved.
32
3rd Design Project Student Solar Water Heater Handout
(Page 2 of 2)
Background
For both types of systems, you will need a pump to move the water or antifreeze around.
Because of the timescale and location of this activity this should be done with a battery operated
pump. Use the graduated cylinder to ensure that every team is heating the same amount of
water and they know how much water they are heating. To build the solar water heaters, basic
steps include lining the cardboard with aluminum foil and cutting holes to zip-tie the tubing to the
cardboard. Then, teams should assemble their systems. Make sure the tub of water is shaded
and covered, if the experiment is done outside. For a closed loop system, make sure you load
the antifreeze before you coil the tubing onto the panel.
1. After completing reading and research, explain how a solar water heating system works.
2. Explain the differences between closed and open loop systems. Highlight the strengths
and weaknesses of each system.
3. In teams, design and create your solar water heating system as instructed by your
teacher.
Intermediate Design Challenge
Using tubing, water, antifreeze, and tubs, design and build an open or closed loop solar water
heater. You should be prepared to present the following to your instructor and your class:
1. Problem statement and how you solved your problem using the engineering design
process
2. Original design of your open or closed loop solar water heater system
3. Working model of your system
4. Measurement and analysis of the rate of heat transfer
Test your solar water heating system using the sun (or a heat lamp if the day is cloudy).
Measure the temperature of your water at designated time intervals with a thermometer. Record
and graph your measurements in your engineering log book. Determine the rate of heat transfer
to the water in your solar water heater. How well did your system work?
Advanced Design System
Do all of the above, plus choose one of the following feedback and control design options to add
to your project. If you are doing the advanced design project, ask your instructor for the
materials list.
1. Design and develop a solar water heating system that uses a feedback and control loop
to switch between heating water with a solar heater and an electric element when the
temperature in the solar water system drops below a certain temperature.
2. Design and develop a solar panel system that uses a feedback and control loop to
change the angle of the panel when the power output of the solar cell drops below a
level that you determine is too low.
Copyright © Texas Education Agency 2012. All rights reserved.
33
3rd Design Project Quiz
Name_________________________________
(Page 1 of 3)
Date__________________________________
Directions: After reviewing the entire lesson and taking notes, complete the quiz. Circle
and write the letter of your answer choice. (2 points per correct answer)
________1. The first human uses of solar energy involved —
A. running street lamps
B. creating fires
C. powering generators
D. running highway signs
________2. The sun can be approximated as a —
A. white radiation source
B. UV radiation source
C. blackbody radiation source
D. IR radiation source
________3. The electromagnetic spectrum includes —
A. visible light
B. IR radiation
C. radio waves
D. All of the above
________4. If a light wave has a wavelength of 400 nanometers (nm), what is its
frequency?
A. 7.5×10-3 s-1
B. 7.5×103 s-1
C. 7.5×1011 s-1
D. 7.5×1014 s-1
________5. Which of the following has the highest energy?
A. A light wave with a wavelength of 600 nm
B. A light wave with the wavelength of 1200 nm
C. A light wave with a frequency of 4×108 s-1
D. A light wave with a frequency of 1×1018 s-1
Copyright © Texas Education Agency 2012. All rights reserved.
34
3rd Design Project Quiz
Name_________________________________
(Page 2 of 3)
Date__________________________________
________6. Which phenomenon proves that light also acts as a particle?
A. Photoelectric effect
B. Particle-wave duality
C. Light diffraction
D. Light refraction
________7. A single-axis tracker system tracks the sun from —
A. north to south
B. north to east
C. east to west
D. west to east
________8. The plant based dye in a Grätzel Cell utilizes the biological principles of —
A. respiration
B. photosynthesis
C. replication
D. photosensitivity
________9. As a closed thermodynamic system the earth can exchange______ with
the rest of the universe.
A. matter
B. temperature
C. energy
D. pressure
________10. When heat transfers thermal energy, in what direction does it move?
A. From a region with a lower temperature to a region with a higher temperature
B. From a region with a higher temperature to a region with a lower temperature
C. Between two regions that have the same temperature
D. All of the above
Copyright © Texas Education Agency 2012. All rights reserved.
35
3rd Design Project Quiz
(Page 3 of 3)
Name_________________________________
Date__________________________________
________11. Thermal energy is transferred through —
A. circadian rhythms
B. molecular rotation
C. molecular collisions
D. electron motion
________12. Solar water heating systems obtain thermal energy from the sun primarily
through what method of heat transfer?
A. Electrical
B. Conduction
C. Convection
D. Radiation
________13. In what type of solar heating system is the water not heated directly by the
sun?
A. Open loop
B. Closed loop
C. Active loop
D. Passive loop
________14. In most feedback and control loops for solar water heaters what is the
primary variable that provides feedback to the system?
A. Time of day
B. Water flow rate
C. Water temperature
D. Water pressure
Copyright © Texas Education Agency 2012. All rights reserved.
36
3rd Design Project Quiz Answers
(Page 1 of 2)
1. The first human uses of Solar Energy involved —
A. running street lamps
B. starting fires
C. powering generators
D. running highway signs
2. The sun can be approximated as a —
A. white radiation source
B. UV radiation source
C. black body radiation source
D. IR radiation source
3. The electromagnetic Spectrum includes —
A. visible light
B. IR radiation
C. radio waves
D. All of the above
4. If a light wave has a wavelength of 400 nanometers (nm), what is its frequency?
A. 7.5×10-3 s-1
B. 7.5×103 s-1
C. 7.5×1011 s-1
D. 7.5×1014 s-1
5. Which of the following has the highest energy?
A. A light wave with a wavelength of 600 nm
B. A light wave with the wavelength of 1200 nm
C. A light wave with a frequency of 4×108 s-1
D. A light wave with a frequency of 1×1018 s-1
6. Which phenomenon proves that light also acts as a particle?
A. Photoelectric effect
B. Particle-wave duality
C. Light diffraction
D. Light refraction
7. A single-axis tracker system tracks the sun from —
A. north to south
B. north to east
C. east to west
D. west to east
8. The plant based dye in a Grätzel cell utilizes the biological principles of —
A. respiration
B. photosynthesis
C. replication
D. photosensitivity
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37
3rd Design Project Quiz Answers
(Page 2 of 2)
9. As a closed thermodynamic system the earth can exchange______ with the rest of the
universe.
A. matter
B. temperature
C. energy
D. pressure
10. When heat transfers thermal energy, in what direction does it move?
A. From a region with a lower temperature to a region with a higher temperature
B. From a region with a higher temperature to a region with a lower temperature
C. Between two regions that have the same temperature
D. All of the above
11. Thermal energy is transferred through —
A. circadian rhythms
B. molecular rotation
C. molecular collisions
D. electron motion
12. Solar water heating systems obtain thermal energy from the sun primarily through what
method of heat transfer?
A. Electrical
B. Conduction
C. Convection
D. Radiation
13. In what type of solar heating system is the water not heated directly by the sun?
A. Open loop
B. Closed loop
C. Active loop
D. Passive loop
14. In most feedback and control loops for solar water heaters what is the primary variable that
provides feedback to the system?
A. Time of day
B. Water flow rate
C. Water temperature
D. Water pressure
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38
3rd Design Project Design Rubric
Criteria Concepts/Skills
to be
Assessed
Solar
Power/Water
Heater System
Sketch, Layout,
and Plan
Solar
Power/Water
Heater System
Design Solution
Drawing
Meets Solar
Power/Water
Heater System
Objectives,
Resources, and
Constraints
Solar
Power/Water
Heater System
Background
Novice
(0-10 points)
Sequence of
information is
difficult to follow.
No apparent
structure or
continuity. Little
evidence of a
cohesive plan.
Sketch is
carelessly
created.
No design
drawing, or
reading and
understanding
drawing is
difficult. Minimal
idea
development.
No key details or
dimensions, or
unrelated
details.
No grasp of
required subject
matter. No
understanding of
major issues. No
interpretation of
results. Does
not pay attention
to the resources
needed and/or
their availability
until it is too late.
Either cannot
identify key
design issues or
treats all issues
Criteria Categories
(Novice to Exemplary)
Developing
Accomplished
(11-14 points)
(15-17 points)
Work is hard to
Information is
follow as there is presented in a
very little
logical manner,
continuity. Some which is easily
evidence of a
followed.
cohesive plan.
Organizes
Sketch not
material in an
detailed enough
appropriate
to convert into
manner.
drawing.
Sketch
converted into
drawing.
Drawing needs
improvement.
Poor idea
development
and sequencing
between sketch
and drawing.
Unelaborated
and/or
repetitious
details. Most key
details and
dimensions
missing.
Uncomfortable
with content.
Only basic
concepts are
Demonstrated
and interpreted.
Poor
identification of
major tasks.
Drawing
communicates
design. Some
idea
development
supported by
relevant details.
Drawing details
make major
points easy to
follow. Drawing
contains most
key details and
dimensions.
Able to elaborate
and explain to
some degree.
Some
identification of
major tasks.
Addresses the
issue of
resources and
their availability.
Little or no
evidence of
analysis or
conclusion.
Correctly
interprets data or
information, but
analysis or
Exemplary
(18-20 points)
Information is
presented in a
logical,
interesting way,
which is easy to
follow.
Organizes
material in a
clear,
appropriate,
and precise
manner. Sketch
easily converted
into drawing.
Drawing
communicates
design clearly.
Evidence of
analysis,
reflection and
insight. Drawing
contains all key
details and
dimensions.
Points
Earned
Demonstration
of full
knowledge of
the subject with
explanations
and elaboration.
Identifies major
tasks needed to
reach
objectives.
Specifies
resources
needed to
complete each
task and
establishes their
availability.
Correct
interpretation of
data or
information.
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39
Research and
Experimentation
Follows
Directions,
Organization,
Team
Management,
and meets
Design criteria
as equally
important or
unimportant.
Little or no
evidence of
research
presented. No
documentation.
No alternate
solutions
identified.
Research is
limited. Some
documentation.
Few possible
solutions
identified.
conclusion may
not be supported
by research.
Identifies design
issues and
prioritizes them.
Good
documentation.
Several possible
Solutions
identified.
Requirements of
the assignment
have not been
fulfilled.
Numerous
errors. Little
evidence of
revision or
editing. Needs
Continual
reminders to
stay "on task.”
Frequently late
and off
schedule.
Shows lack of
judgment. No
attempt is made
to identify and
categorize
necessary tasks.
Some
requirements
have been
fulfilled.
Several errors.
Some evidence
of revision and
editing.
Demonstrates a
somewhat
organized
approach with
regular work
habits.
Follows all
requirements for
the assignment.
Minor errors.
Much evidence
of revision and
editing. Performs
in a satisfactory
way with some
supervision.
Demonstrates
awareness of
progress and
remains more or
less on
schedule. Most
judgments about
priorities are
appropriate.
Identifies key
design issues
and priorities.
Analysis and
conclusion are
based on
research.
Thoroughly
documented.
Many possible
solutions
identified.
Completed all
requirements.
Negligible
errors. Effective
editing and
revisions
improve overall
quality of work.
Able to make
progress on
project with
minimal
supervision.
Consistently on
time in
completing
tasks.
Teacher Notes:
Total
Points
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40
3rd Design Project Presentation Rubric
Criteria Categories
(Novice to Exemplary)
Presentation
Criteria
(Concepts/Skills
to be Assessed)
Content
Preparedness
Time-Limit
Novice
(0-10 points)
Accomplished
(15-17 points)
Exemplary
(18-20 points)
Does not seem
to understand
the topic very
well
Shows a good
Shows a good
Shows a full
understanding of understanding of understanding of
parts of the topic the topic
the topic
The team does
not seem at all
prepared to
present.
The team is
somewhat
prepared, but it is
clear that
rehearsal was
lacking.
Presentation is
less than 1
minute.
Presentation is 1- Presentation is 2- Presentation is 32 minutes long.
3 minutes long.
5 minutes long.
The team
members often
mumble, can’t
be understood,
Speaks Clearly
or mispronounce
more than one
word.
Visual Aids
Developing
(11-14 points)
The team uses
no visual aids or
the visual aids
chosen detract
from the
presentation.
The team seems
pretty prepared,
but might have
needed 1-2 more
rehearsals.
Points
Earned
The team is
completely
prepared and has
obviously
rehearsed.
The team
members speak
clearly and
distinctly most of
the time.
Mispronounces
no more than one
word
The team
members speak
clearly and
distinctly all the
time, but
mispronounce
one word.
The team
members speak
clearly and
distinctly all the
time, and
mispronounce no
words.
The team uses 1
visual aid which
makes the
presentation
better.
The team uses 2
visual aids that
shows
considerable
work/creativity
and which make
the presentation
better.
The team uses
several visual
aids that show
considerable
work/creativity
and which make
the presentation
better.
Teacher Notes:
Total
Points
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41
Team Contract Spreadsheet
Name:
Date Assigned
Date Due
Assignment
Date complete
Late?
Name:
Date Assigned
Date Due
Assignment
Date complete
Late?
Name:
Date Assigned
Date Due
Assignment
Date complete
Late?
Name:
Date Assigned
Date Due
Assignment
Date complete
Late?
Team Signatures: _________________________
_____________________________
_________________________
_____________________________
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42