Solar Cell Investigations, L1-1010.00, £18.00
Each mono-crystaline solar panel has a maximum rating of 4.4V, 90mA. It can be easily energised by a bright lamp or sunlight and can be operated in conjunction with our Solar Motor and Smiley Green Man LED. In addition this Investigations board lets students explore the difference between connecting cells in series and parallel. It also allows students to explore how the loading effect on the cells effects their operation.
Lots of interesting investigations are possible, e.g.
• With no load, measure the output with the cells in series and then in parallel. Replace the voltmeter with a Solar Motor. Does it go faster with the cells in series or in parallel? Perhaps surprisingly it goes faster when the cells are in parallel - under no load conditions the parallel combination gives the smallest output voltage. Now connect a voltmeter across the motor and note the series and parallel voltages. The parallel combination now gives the larger voltage. This should enable your students to appreciate that the electrical load affects the output voltage of the solar cell.
• For a fixed light intensity, determine the optimum electrical load for maximum power transfer when the cells are in series and then in parallel.
• Investigate how the optimum maximum load changes as the light intensity changes.
• Investigate how the output voltage varies with the area of cell exposed to the light.
• Use filters to investigate how the output voltage varies with colour/wavelength of light.
• Use a light meter and investigate how the output voltage varies with light intensity.
Below are typical results:
The Table and graph show the results for the two solar cells connected in parallel with a light intensity of 2940 lux.
Graphs drawn using the ALBA Data Logging software - demo version available free.
These plots show that for cells in series the optimum load for maximum power transfer changes as the light intensity changes.
These plots show that for cells in parallel the optimum load for maximum power transfer changes as the light intensity changes.