Before you carry out your investigations you might like to try the following activity:
Can you make a 6V buzzer work with any of the PV solar cells using natural light as your source. Is it possible to do this on an overcast or sunny day?
How does light intensity affect the output voltage of a solar PV cell? Use two lamps each with a 60W tungsten filament bulb. Place the PV cell at distances of 4cm, 12cm, and 25cm from the light source. The solar cell should be held facing directly at the light source. Measure the voltage of the cell at these distances. Draw a graph of voltage against distance. What does this graph tell you?
How does the colour of light affect the output from the PV cell? Shine different coloured lights at the PV cell and measure the output from each cell. What factors will you have to keep constant in this experiment? What methods can you think of to produce different coloured lights? How might the colour affect the intensity of light – how could you check this?
How does angle to the light source affect the output voltage of a solar PV cell?
- place their PV cell on a horizontal surface in direct sunlight (or other light source) – measure the output voltage.
- point the PV cell directly at the light source (slant it so that its shadow is directly behind it), with the cell’s face perpendicular to the light source. Measure the output voltage.
- tilt the PV cell at an angle of 15 degrees. Measure the voltage. Repeat the measurements at 15 degree intervals.
- plot a graph of voltage against angle – what pattern do you notice?
Other ideas for investigations
How does concentrating a light affect how much electricity a solar cell can produce? Does temperature affect the output of a PV cell? Does the load connected to the PV cell affect the output? Do PV cells in series or parallel affect how much electricity they can produce?