You will be provided with a solar cell module (somewhat smaller than that pictured above) that you will test for various properties such as voltage and power output. You will design your own tests using equipment available in the physics lab. When you have put together a preliminary plan for the tests, you will present it to the instructor for comments and discussion to finalize the plan.

In addition to designing your tests, you will research photovoltaics on the net. It is permissible to also consult physical text at the library.

NET RESEARCH

First, you need to familiarize yourself with photovoltaic technology and terminology. A good starting place is a tutorial by the American Solar Energy Society. A student at Flensburg University in Germany, Suresh Bhagavatula, has also put together a worthwhile introduction. More details can be found through the non-profit Soltice Foundation, through the US Dept of Energy and through the many sources listed at the Related Websites page provided by the ASE Society. These links include several Universities involved with photovoltaic research. Many of the sights have e-mail links to people who might be happy to answer questions. If you need information on a specific subject or problem, there are many search engines (for example, HotBot, and Infoseek) available.

EXPERIMENT DESIGN

Design and implement experiments to determine the following:

1. Voltage and Power Output Related to Incident Radiation and Load
   • Determine the open voltage (no load) output of the solar panel as a function of incident radiation.
   • Determine the voltage output as a function of the load resistance.
   • Determine the power output as a function of the load resistance. Determine the value of the resistance that maximizes the power output.

     NOTES AND SUGGESTIONS: You will need to think about the light source. What should the source be and how will you control or monitor it during the test? How does the level of light effect the tests above? You will also need to take some preliminary tests to determine the range of voltages and currents you will encounter so that you can choose appropriate equipment.

2. Power Output Related to Environmental Conditions
   • Determine the maximum power output as a function of the angular location of the sun in the sky.
   • Determine the power output as a function of the angle of incidence between the sun's rays and the normal to the plane of the solar panel.

     NOTES AND SUGGESTIONS: At least part of this testing phase will require outdoor activity. You should consider how you will handle variations other than the position of the sun in the sky.

REPORT

The lab report should begin with a two to three page introduction to photovoltaics based upon your net research. The into may be broad in scope or may focus upon one or more aspects that you find interesting.

The intro should be followed with the standard format report of your tests. Remember that you have designed these tests. Consequently, you need to provide complete and accurate descriptions for the reader in the equipment and procedure sections. In the report, present your results with appropriate graphs, plots, and diagrams. Your conclusions should explain what you have measured and describe the significance of what you have measured. For example, what are your recommendations to the reader who may wish to use this solar panel? For example, what direct loads would you recommend and what suggestions would you make concerning installation?