3.1 What are clean energy sources?  

Instructional Sequence

Materials: Teacher slides 3.1 What are clean energy sources？

Slide 1

The teacher will call back students‘ learning about a hand crank generator as an introduction to clean energy.  In this slide, the teacher would tell students that clean energy could turn lights on without using fossil fuels. In this way, clean energy will be another way to reduce co2 emissions. But what are common clean energy sources in our life? 

Slide 2-4

With slide 2-4, teacher could ask students:

• What are clean energy sources they heard about before? 

• Why is clean energy cleaner than fossil fuels? 

Students‘ comments about clean energy are expected to be all good. But these advantages about clean energy do not necessarily end up with an easier transition from fossil fuel to clean energy sources. The teacher could show students slide 5, explaining the table “U.S. Energy consumption by source, 2021,”  asking students to report the points they notice in the left table.

The main point here is to show that:

1. Fossil fuel holds almost 80% of energy consumption in the U.S.

2. Clean energy sources still account for a small portion of U.S. energy consumption despite its recognized advantages. 

3. Nuclear energy is one clean energy source used most in the U.S.

Slide 6 So, teachers could lead students to think another question based on the table: 

• Why is it still so hard to shift from fossil fuels to clean energy though they are cleaner? 

Slide 7-8

The teacher will take nuclear energy as an example to let students understand the difficulties in shifting energy use. Taking two figures about nuclear energy use in both U.S. and state of North Carolina, the teacher could lecture about two figures and consider including the main points like:

1. North Carolina is becoming one of the ten states using most nuclear energy in the U.S. by 2022.

2. Electricity generated with nuclear energy holds 32% of total electricity produced in NC in 2017.

Slide 9 Starting to learn about nuclear energy in detail. 

The teacher will give all students a reading about nuclear energy and have students read it within 3 minutes. 

Slide 10 After reading, the teacher could work with students to summarize main takeaways from the reading card :

1. Uranium is the main fuel used to produce nuclear energy, which is a nonrenewable resource.

2. Uranium atoms are split in the process of fission to produce a large amount of heat.

3. The heat is used to turn water into steam, making a turbine spin and generate electricity.

Slide 11 Then, the teacher could further invite students to draw a diagram together, showing their initial understanding of the working mechanism of nuclear energy.  During this process, the teacher could write down main components and flows offered/shouted out by students on the white board. At the same time, the teacher could also have students draw these components with different representations.(An example of diagram is presented on slide 12)

Then, with slides 13-14, the teacher and students could watch the video “Nuclear energy: Risk or Opportunity'' and read a short passage regarding additional advantages and concerns about nuclear energy together. Prior to that, the teacher could remind students of the pros and cons of nuclear energy and jot down main points in their scratch paper. After that, teacher would invite students to share their main takeaways and then summarize them into following points (slide 15):

1. The economic and environmental costs caused by fossil fuels necessitate alternative  ways to support humans‘ energy needs.

2. The working mechanism of most nuclear power plants: the atoms of Uranium undergo a chain reaction, hit by neutrons and splitted into smaller atoms, releasing a lot of heat, which is used to heat water,  generate steam, and spin the turbine for making electricity. 

3. Nuclear energy has a huge potential to be used on a large scale mainly because of its high efficiency of energy generation and ability to constantly generate a large amount of energy.

4. Potential safety concerns:release of radioactive materials when it was crashed down by unexpected accidents.

Slide 16, The teacher will lead students to call out the pros and cons of nuclear energy after reading and watching a video. The potential pros and cons of nuclear energy derived from the video and readings: 

• Pros-(1) lack of direct carbon emission;(2) ability to generate huge energy;(3)reliable and efficient power production.

• Cons-(1) indirect carbon emission in construction of facilities and obtainment of fuel;(2) safety concerns, e,g., release of high-level radioactive chemicals;(3) Nuclear waste management;(4) high expense in upgrade and regular maintenance of facilities.

Slide 18-24

Have students work in groups, explore the solar, wind, and hydropower energy through reading and watching explanatory videos. Then, students will share what they learned about energy with other groups. Specifically, The whole class could be separated into several groups (based on the number of students), focusing on solar, wind, and hydropower energy respectively. One or two groups focus on a type of clean energy source and are responsible to orally present  their learning results to the whole class. The leading presenter could choose to write down their main points or diagrams on a white board so that other students could see their reported takeaways. If there are two or more groups of students focusing on the same topic, the teacher might need to invite other groups to add more points missed in the presentation. At the same time, students from the other two clean energy sources could  take notes on their worksheets while the leading group is presenting. 

After each group’s presentation, the teacher could quickly summarize the presentation and wrap up this lesson with an open-ended question “ why is it still so hard to shift from fossil fuels to clean energy sources? ”  The teacher could lead discussion towards the importance of  stability/amount in energy consumption in society. Although the clean energy sources are more environmentally friendly, the increasing demand of energy consumption relies on more economical and stable energy sources. Moreover, it is also important to point out that new technology innovation could fasten the transition from fossil fuel to clean energy sources.