During this lesson, students are guided through an initial understanding of electrical energy and production. As their learning progresses, they will explore energy production using photovoltaics (PVs) and use the National Renewable Energy Lab’s (NREL) on-line simulator, PVWatts. The synthesis of this information will result in a basic understanding of the economics of solar energy production. Secondary students will continue their research by accessing their state’s energy portfolio through the U.S. Energy Information Administration (EIA). Students will synthesize what they have learned and apply Design Thinking Skills to create a Solar Charging Station or a model Electric Car.
Author: David Sander
View the lesson and supporting documents here.
- Introduction
- Curriculum Alignment
- Lesson Objectives
- Time & Location
- Teacher Materials
- Student Materials
- Safety
- Student Prior Knowledge
- Teacher Preparations
- Activities
- Assessment
- Critical Vocabulary
- Author Information
Introduction
During this lesson, students are guided through an initial understanding of electrical energy and production. As their learning progresses, they will explore energy production using photovoltaics (PVs) and use the National Renewable Energy Lab’s (NREL) on-line simulator, PVWatts. The synthesis of this information will result in a basic understanding of the economics of solar energy production. Secondary students will continue their research by accessing their state’s energy portfolio through the U.S. Energy Information Administration (EIA). Students will synthesize what they have learned and apply Design Thinking Skills to create a Solar Charging Station or a model Electric Car.
Curriculum Alignment
Although this lesson could be taught through many different courses, I have chosen to document the alignment through the North Carolina Standard Course of Study for Science. While the lesson does not cover every objective comprehensively, it serves as a platform that will allow students to apply these concepts. It is entirely possible to collaborate and teach this as students progress through each course at each grade level, with the culminating activity taking place as they are taking Physics, though there is no guaranteed way to ensure that every student will take Physics before they graduate. I intend to teach this lesson through Technology, Engineering, & Design (TE11) as a way to reinforce and apply what they have learned or will learn in their science courses.
Activity 1
Physical Science 3.3.1 Summarize static and current electricity.
Physical Science 3.3.2 Explain simple series and parallel DC circuits in terms of Ohm’s law.
Physical Science 3.3.5 Explain the practical application of magnetism.
Physics 2.3.1 Explain Ohm’s law in relation to electric circuits.
Physics 2.3.2 Differentiate the behavior of moving charges in conductors and insulators.
Physics 2.3.3 Compare the general characteristics of AC and DC systems without calculations.
Physics 2.3.4 Analyze electric systems in terms of their energy and power.
Physics 2.3.5 Analyze systems with multiple potential differences and resistors connected in series and parallel circuits, both conceptually and mathematically, in terms of voltage, current and resistance.
Activities 4, 5, & 6
Earth and Environmental Science 2.2.1 Explain the consequences of human activities on the lithosphere (such as mining, deforestation, agriculture, overgrazing, urbanization, and land use) past and present.
Earth and Environmental Science 2.2.2 Compare the various methods humans use to acquire traditional energy sources (such as peat, coal, oil, natural gas, nuclear fission, and wood).
Earth and Environmental Science 2.5.5 Explain how human activities affect air quality.
Earth and Environmental Science 2.6.3 Analyze the impacts that human activities have on global climate change (such as burning hydrocarbons, greenhouse effect, and deforestation).
Earth and Environmental Science 2.8.1 Evaluate alternative energy technologies for use in North Carolina.
Activity 8
Physical Science 3.1.2 Explain the law of conservation of energy in a mechanical system in terms of kinetic energy, potential energy and heat.
Physical Science 3.1.3 Explain work in terms of the relationship among the applied force to an object, the resulting displacement of the object, and the energy transferred to an object.
Physics 1.2.3 Explain forces using Newton’s laws of motion as well as the universal law of gravitation.
Physics 1.2.4 Explain the effects of forces (including weight, normal, tension and friction) on objects.
Physics 2.1.1 Interpret data on work and energy presented graphically and numerically.
Physics 2.1.2 Compare the concepts of potential and kinetic energy and conservation of total mechanical energy in the description of the motion of objects.
Physics 2.1.3 Explain the relationship among work, power and energy
Lesson Objectives
- Students will understand energy, power, voltage, and current as well as AC and DC power systems as it relates to solar energy production.
- Students will understand how photovoltaics work.
- Students will understand the ideal solar array configuration based on their geographic location.
- Students will understand the benefits and barriers of solar energy.
- Students will calculate their state’s energy production portfolio.
- Students will understand the components of a Life Cycle Analysis (LCA)for various power plants.
- Students will create a proposal to install a solar array at their school that provides the projected energy savings, emission reductions, and return on investment.
- Students will create a solar charging station and an electric car to test the effectiveness of the solar charging station and the efficiency of the car.
Time & Location
6-15 Days
The first 3 days of these activities can be performed either through a direct presentation (lecture) or through individual student research if they have access to a laptop/tablet. Activities 4 and 6 should be completed in a computer lab or where the students have a minimum of a 1:2 device to student ratio. Days 5-15 should be facilitated in a classroom with crafting tools such as soldering guns, hot glue, X-acto knives, rulers, scissors, and some work tables.
Day 1
Activity 1 – Computer Lab or Classroom
45 minutes
Students will explore the concepts of energy, power, voltage, and current as well as AC and DC power systems as it relates to solar energy production.
This is primarily designed to give students a basic understanding of the vocabulary used in the remaining activities.
Activity 2 – Computer Lab or Classroom + Outside Activity
45 minutes
Students will explore how photovoltaics work.
Day 2
Activity 3 – Computer Lab or Classroom
45 minutes
Students will explore the ideal solar array configuration based on their geographic location. (NREL PVWatts Solar Array Simulator)
Activity 4 – Computer Lab
45 minutes
Students will explore the benefits and barriers of solar energy.
Day 3
Activity 5 – Computer Lab
90 minutes
Students will calculate their state’s energy production portfolio and present them to the class. (EIA Data and Google Sheets to create a Pie Chart)
Day 4
Activity 6 – Computer Lab or Classroom
30 minutes
Students will explore the environmental impacts of energy production through a Life Cycle Analysis (LCA) for various power plants.
Activity 7 – Computer Lab or Classroom
60 minutes
Students will create a proposal to install a solar array at their school that provides the projected energy savings, emission reductions, and return on investment.
Day 5-15
Activity 8 – Classroom
2-10 Days
Student teams will use Design Modeling and apply scientific principles to design and create a solar charging station or an electric car.
Depending on how you plan to facilitate this activity, it will range from 2-10 days. If you want teams to design and build cars and charging stations from scratch, it will take 10 days; 2 days for the charging stations and 8 days for the cars. However, I allowed my introductory class (mostly 9th & 10th graders) to build LEGO cars and this sped the development up significantly. I also had students pair up and they “drew out of a hat” their assigned project. Half of the class made cars while the other half made charging stations. They designed and fabricated them independently from each other and then presented their solution to the class the day before testing and each team agreed upon an “alliance” so that each charging station had an alliance with a car. In a class of 24 students, we had 6 cars and 6 charging stations. Obviously, you will need to determine how to implement this based on your available supplies/equipment. I discuss this in the teacher resources folder.
Teacher Materials
Because this is such an involved lesson, with many options for supplies and materials, I have included a teacher resources folder that explains what to use and when to use it, along with suggestions for alternatives.
Student Materials
- Student Notes Handout (1 copy for each student)
- Solar Array Instructions Activity 3 (post to web)
- Activity 3 Student Worksheet (last page of activity – 1 copy for each student)
- Activity 4 Student Worksheet (last page of activity – 1 copy for each student)
- State Energy Portfolio Instructions Activity 5 (post to web)
Safety
While working with electricity involves some safety considerations, the voltage and current are so low that students are more inclined to get injured using a hot glue gun or heavy-duty scissors while cutting cardboard. Nevertheless, safety is never something to take lightly. Hot glue guns do not have hot glue; it is actually molten plastic at temperatures that reach well above boiling water. If they would not immerse their hands in a pot of boiling water, they should be careful not to let the molten plastic touch their skin. Also, as teams craft their charging stations, they will be cutting foam board or cardboard (corrugated paper). When applying high levels of force to very sharp heavy-duty scissors, they should keep the cutting tools away from each other. If a teacher chooses to allow students to use X-acto knives, extra precautions should be in place to prevent injury to both student and furniture. The solar panels are rated at 3 Volts at 1.5 Amps for a total of 4.5 Watts. While less than 1 amp can stop your heart, you need significantly more Voltage (about 100 Volts) to pass through the human body. In addition, the rechargeable AA batteries only produce 1.2 Volts each. Though they are capable of higher currents than the solar panel, they are at such a low voltage they pose a minimal safety threat.
Student Prior Knowledge
Students are not required to know anything for this lesson, however it would be beneficial for them to have some experience with the application of an Engineering Design Process, Design Thinking, or some other form of Project Management. Depending on the depth of the lesson, students may also need design skills though Google SketchUp or Autodesk Inventor.
Teacher Preparations
Teachers will need to determine what works best for them based on their facilities and supplies. It is highly recommended that the teacher practice each lesson they intend to use before they introduce it to the students. This way they can draw upon their prior experiences from labs or activities and they will create their own lists of resources needed for each activity.
Activities
Activity 1 – Students will explore the concepts of energy, power, voltage, and current as well as AC and DC power systems as it relates to solar energy production.
This activity can be performed either through a direct presentation (lecture) or through individual student research if they have access to a laptop/tablet. This is primarily designed to give students a basic understanding of the vocabulary used in the remaining activities.
Activity 2 – Students will explore how photovoltaics work.
Students will connect small solar panels together in series and parallel circuits. Voltage will be measured using a multimeter. Students will also power a small electric device (i.e. a dc fan) and compare the results. Students will also watch a visualization on how photovoltaics work and research the efficiencies of various solar panel types (amorphous, monocrystalline, polycrystalline, focusing, quantum dot, etc.)
Activity 3 – Students will explore the ideal solar array configuration based on their geographic location.
Students will explore the NREL PVWatts web-based simulator. They will manipulate the variables within the simulator (i.e. array type, tilt, azimuth, etc.) and determine the optimum projected power output for a 5 kW solar array with a 10% energy loss calculation (exceptional students may extend their research to include energy loss factors and brainstorm solutions to each one). Student work will be evaluated through the included student worksheet.
Activity 4 – Students will explore the benefits and barriers of solar energy.
This lesson either allows them to work in groups to research the benefits and barriers of solar energy from which they can create a mind map of how the concepts are related and presented back to the class OR this can be explained directly by the teacher with the included PowerPoint. One key connection that should be made are the number of skill-based jobs available in the renewable energy industry.
Activity 5 – Students will calculate their state’s energy production portfolio.
Students will explore the EIA website and create a pie chart and a graphic that they can present to the class. Teachers may assign each student a different state to investigate based on where they are from or where they might have traveled. Included in the teacher resources folder is an example that you can present. The student product may be evaluated based on the provided example.
Activity 6 – Students will explore the environmental impacts of energy production through a Life Cycle Analysis (LCA) for various power plants.
The teacher will engage student learning by explaining and elaborating through the provided PowerPoint.
Activity 7 – Students will create a proposal to install a solar array at their school that provides the projected energy savings, environmental benefits, and return on investment.
This is an optional activity. There are many organizations that provide grants or matching funds for schools to have a grid-tied solar array installed at their school. In many cases, the equipment collects data that the teacher can use to expand upon this lesson and allow students to calculate the displaced CO2 from the energy produced by their solar array. It can also serve as a visual reminder that we can all take steps to lessen our impact on the environment.
Activity 8 – Students will apply Design Thinking Skills to create a solution to a renewable energy problem.
Student teams will create a solar charging station or an electric car. Teams of 2 students will build a solar charging station or an electric car which will be presented to the class. Teams will form alliances based on their product and presentation. Alliances will test their systems by charging 2 AA rechargeable batteries using their solar charging station and use the batteries to power the electric car in a race against the other alliances. Teams will be evaluated based on the performance of their charging station and their vehicle.
Assessment
Teachers will evaluate student work in lessons 3, 5, & 8.
Activity 3 will be evaluated through the completion of the provided student handout.
Activity 5 will be evaluated through a comparison of the provided State Energy Portfolio. The teacher has the option to grade any and all aspects of the activity; the pie chart, the entire graphic, and the presentation.
Activity 8 will be evaluated through the provided grading scale, though the teacher has the discretion to modify this according to their preferences.
Critical Vocabulary
Voltage
Current
Power
Energy
Photovoltaics
Emissions
Greenhouse Gas
Return on Investment (ROI)
Energy Portfolio
Life Cycle Analysis (LCA)
Author Information
David Sander has been teaching Technology, Engineering, & Design Education at Wake Forest High School in Wake County since 1995. He has been involved with numerous projects with his students that involve renewable energy. These projects include building a full size street legal electric car, growing algae to create ethanol, off-grid power systems for residential housing, a solar tracking system for a photovoltaic array, and as the advisor for the Sustainable Transportation Education Program (STEP) supported by the FREEDM Systems Center.
Alexis Aguirre is a rising junior at the University of Texas at El Paso (UTEP). He is majoring in electrical engineering and minoring in computer science. He was selected to participate the FREEDM Systems Center Research Experience for Undergraduates (REU) program in the summer of 2017. Prior to college, he graduated from the Project Lead the Way (PLTW) Engineering Magnet Program at Chapin High School in El Paso, Texas, guiding him towards choosing an engineering field of study. He has become increasingly involved in his school with the Institute of Electrical and Electronics Engineers (IEEE) UTEP chapter, a professional association for electrical engineers, where he recently participated with a Micromouse team. He has also been a part of professional development organizations like Latinos in Science and Engineering (MAES) and Society of Hispanic Professional Engineers (SHPE), with whom he will serve as Director of Outreach to help engage high school and middle school students throughout the El Paso area into engineering.
Dr. Pam Carpenter is the Education Director at the FREEDM Systems Center at North Carolina State University. She has been involved in educating a new generation of engineers and scientists to research renewable energy based electric power systems as well as multiple outreach programs such as GRIDc (Green Research for Incorporating Data in the Classroom), STEP (Sustainable Transportation Education Program) and the EV Challenge.
Dr. Ewan Pritchard is the Associate Director of the FREEDM Systems Center and the Advanced Transportation Energy Center at NC State University. He helps manage the portfolio of research from approximately 200 researchers working on updating the electric utility grid to be more welcoming for renewable energy, integrate new technologies (like electric vehicles), more reliable, and less expensive. He also works to manage the long term vision of the Center and manages key relationships to ensure the sustainability of the center. With ATEC, he works with the automotive industry to learn the hurdles to the adoption of vehicle electrification and how NC State can overcome those hurdles. Dr. Pritchard is best known for his work to bring plug-in hybrid school buses to the market. He has been involved with the energy and transportation industry since 1997 and he has worked with numerous vehicle companies and organizations to develop innovative electric and plug-in platforms to reduce environmental emissions and fuel consumption. More recently, Dr. Pritchard was one of the authors of the proposal for a $146M Wide Bandgap Semiconductor Institute to be housed at NC State University.
egpritch@ncsu.edu