Activity

Solar panel

Summary
Light a bulb or turn a fan with a solar panel, with light from a flashlight or lightbulb.
Science content
Physics: Energy forms, Conservation of Energy (1, 3, 4, 5)
Physics: Electricity, Electromagnetism (7)
Earth/Space: Sustainable practices, Interconnectedness (2, 5, 7)
Science competencies (+ questioning + manipulation + others that are in every activity)
Questioning/predicting: predicting (1 up), hypothesizing (7)
Planning/conducting: planning investigations (3 up)
Processing/analyzing: comparing observations with predictions (1 up)
Processing/analyzing: considering alternative explanations (5 up)
Evaluating: inferring (3 up)
Evaluating: identifying environmental implications (1 up)
LED flashlight on the solar panel lights a super red LED bulb
incandescent bulb on the solar panel brightly lights a super red LED bulb
incandescent bulb on the solar panel dimly lights a 3V LED bulb
incandescent bulb on the solar panel turns a fan
measure fan speed with varying bulb distance
full sun on the solar panel turns the fan
Lessons activity is in
Energy from fossil fuels and renewable sources
Electricity and renewable ways of generating it
Materials
  • solar panels (mine are 0.3W 5V from AliExpress)
  • flashlight/light bulb
  • LED bulbs including a low voltage 'super red'
  • optional: small fan (test first) - mine is a toy windmill attached to this generator
Procedure

Test before use to make sure the solar panel makes enough power to light the bulb/turn the fan.

Connect the solar panel wires with the LED terminals, matching black to black and red to red - do this by crossing the wires and taping to the tabletop, so that the connection can be easily checked and redone.
Shine the flashlight or light bulb on the solar panel to make electricity which can turn on the LED light. An incandescent bulb will light the LED more brightly than an LED flashlight.

Now connect the solar panel wires to the fan.
My LED flashlight does not turn the fan, but an incandescent bulb can.
Bright sun through a window can also turn the fan.

The light energy of the flashlight/lightbulb/sun is converted to electrical energy in the solar panel.
This electricity is converted back to light energy in a bulb, or to motion energy in a fan.

Discuss the energy transformations, from light energy to electrical energy to light/motion energy.
Discuss renewable energy sources of electricity.

Grades taught
Gr 4
Gr 5
Gr 7