Solar Relay

1. Mark off a portion of the ground with cones into two large rectangular areas, with enough space to hold all students.
2. Place the labels inside the rectangles.
3. Use the rope to make a path around the area, representing an electrical circuit.

1. Ask students to brainstorm what we use electricity for. For example: lighting, tv, phone – get at least one with rechargeable batteries.
2. Brainstorm why people would want to use renewable energy. Some examples include:
   • Help the environment
   • Less habitat destruction (from mining)
   • Less air pollution
   • Energy stability (we will not run out)
3. Ask students if anyone knows how solar panels produce electricity. Some examples include:
   • In a coal or natural gas power plant: burning these fuels near water creates steam, steam spins a turbine, which spins a generator, the spinning moves tiny particles called electrons along wires to produce electricity.
   • In a solar panel: solar energy is changed to electrical energy, electrons are excited by the sunlight and move along the wire.

1. Students will be playing the role of electrons in a solar cell and an electrical circuit. (See below)
2. Show the students the area representing the solar panel: The Positive layer, the Negative layer, and the Positive-Negative (p-n junction).
3. Explain to students that the junction acts like a one-way door through which electrons can pass from the positive layer into the negative layer, but not the other way!
4. When everyone is positioned, start the simulation:
   • The Sun “shines” on the solar cell.
   • Electrons in the solar cell begin moving and wiggling around.
   • Walk and wiggle until they reach the edge of their layer, then turn and walk in a different direction until they reach the next edge.
   • Electrons in the positive layer eventually move, one by one, into the negative layer.
   • The p-n junction allows electrons to pass into the negative layer but prevents wiggly electrons in the negative layer from moving back (with optional barrier students).
   • The only place for the electrons in the negative layer to go is into the wire.
   • Have one electron enter the wire.
   • Electron students along the wire move forward along the wire back towards the positive layer.

1. Have the students playing appliances “turn on” when electrons are moving.
2. Encourage students to do the motions/sounds of the devices!
   • Appliances stay on as long as the sun is shining.
3. Electrons give appliances a high-five as they pass to simulate energy transfer.
4. When an electron enters the wire, an electron at the other end of the wire can step into the positive layer.
5. After an electron enters the positive layer from the wire, the student should move and wiggle until it is their turn to enter the negative layer.
6. With practice, the electrons should cyclically move from the positive layer into the negative layer, through the wire, and back to the positive layer, completing the circuit.
7. Change the flow of the electrons by having the sun “set” or get blocked by the cloud.
8. Ask students what would happen to the electron flow (slows or stops).

1. Reflect on why solar panels are a renewable source of energy:
   • Will we ever run out of the sun?
   • Are there any waste products of solar energy?
2. Describe potential drawbacks of solar PV:
   • Solar energy is not always available (such as at night).
   • It is not consistently sunny everywhere.
   • It might be difficult to get solar panels.
   • It requires a large initial investment.

• Generate Electricity – How Solar Panels Work! – Use in the first discussion or prior to activities.