Solar Panels

Submitted: Monday, Jun 30, 2003 at 10:32

ThreadID: 5734 Views:1759 Replies:2 FollowUps:2

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Hoffy

Is there a life span for solar panels? I have been offered some 60 watt panels for a very reasonable price. I understand they are BP panels however they have been in use for 10 years. Does the performance of panel drop off when constantly being in the sun? What is the best method of checking the performance of these panels out - measururing the short circuit current and comparing this with a new unit? Any advice would be appreciated.

Keith

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Reply By: joc45 - Monday, Jun 30, 2003 at 11:54

Monday, Jun 30, 2003 at 11:54

As I understand them, the performance does taper off a bit over 20 years, but not enough to worry about. My BP panels are over 10 years old and working fine. If the glass is not cracked, the frames are in good condition, there is no obvious ingress of moisture into the laminate, and the price is right, grab them.

Your method of testing sounds fine, as there are too many variables in for simple testing of the panel into a battery. Do you have the specs for max short-circuit current? If it's a BP160 (60w) then the short circuit current is 3.7A and voltage is 21.4v open circuit. This is usually quoted at 25degC and the output will taper off a bit as the panel warms up in the sun. But remember that a sunny winter's day in southern states may not give you the full solar input.
good luck
Gerry

AnswerID: 23835

Follow Up By: Hoffy - Tuesday, Jul 01, 2003 at 09:27

Tuesday, Jul 01, 2003 at 09:27

Thanks Gerry for the information. I will check the panels out. They are on the roof of a house not far from here and put out of service when the person eventually had the mains power connected to the property. I will compare the short circuit current of each of them, same time same location, with my BP 40 watt panel which has spent very little time in the sun. The asking price ia about 1/3 of the current price.
Keith

FollowupID: 16035