Solar Panel Efficiency Project

[AMHS1994]

Hello, I am completely new to this, and am in dire need of help for my project.
My project is to test the efficiency of a particular solar panel.
What I need to know is how to calculate the input (which is sunlight, I think), and I already know how to do the output using a multimeter.
Also, I was wondering, how do I make it into a workable experiment? Do I test the efficiency for it at different times of the day, or on different days?
Please help me, thank you.

[avandalen]

Hello, I am completely new to this, and am in dire need of help for my project.
My project is to test the efficiency of a particular solar panel.
What I need to know is how to calculate the input (which is sunlight, I think), and I already know how to do the output using a multimeter.
Also, I was wondering, how do I make it into a workable experiment? Do I test the efficiency for it at different times of the day, or on different days?
Please help me, thank you.

In theory the efficiency can be calculated as follows. Assume that the suns power is 1000W/m2. When the PV panels output is 200W for 1m2, the efficiency is 20%.
Unfortunately the sun is not calibrated.
Without a calibrated light source for the whole PV panel you can

[russ]

Unfortunately the 1000 watts/m2 is kind of an imaginary number. A few days during the summer it is reached for a short period of time each day. That is from DNR (direct normal radiation) measurements off my weather station.

Please see and go through the thread.

http://www.solarpaneltalk.com/showthread.php?2813-Measuring-available-solar-energy/page2

If you can calibrate one cell as shown in that thread to a known light quantity you should be in business - you would have a base to work from.