So I won an old but decent looking poly-crystalline Solavolt panel on Ebay (
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ih=009&item=190030338481 ) a week ago. It was advertised as 50 watts. There isn't a lable that has the specs on it, and the model/serial number is illegible. Well, I finally got a really clear day to take some power readings.
At 1 o'clock in the afternoon, on a very clear day after a cold front blew through, I took the following readings:
Voc: 20.0
Isc: 3.25
Then I connected the panel directly to my car battery, (original battery in a 1997 Mazda Miata) turned on the park, trunk, and dome lights to create some drain, and got the following figures:
12.2 volts and 3.0 amps, which would equal only 36.6 watts
I guess this seems right, being connected directly to the battery. I know panels are basically constant current devices, and the only way to see an increase in wattage is to have a higher voltage. It just seemed depressingly low, but I guess it's right.
I plan on using it to directly power two El-Sid PV circulator pumps, for a solar hot system, so I should have plenty of power.
