Cleantechnica has a look at the long term performance of solar panels - Carter Era Solar Panel Performance Amazes Owner.
A story in Green building advisor sheds some light on how long the solar panels on your roof just might keep on pumping out power.
While most appliances only use energy, rather than make energy, and are not subject to the rigorous second-guessing of solar arrays (when was the last time you demanded a payback analysis on your car, your fridge or your giant plasma TV?) a solar array is just an appliance that supplies a personal power supply, after all. Like a car, a fridge, or a plasma TV, it provides you with a service.
So, will it outlast your car, fridge and plasma TV? Apparently: yes.
Green Building Advisor’s Green Building’s Martin Holladay tested the 30 year old solar panel that he originally purchased and installed in 1980. To mark the 30th anniversary, Holladay climbed on his roof and brought one of his panels down for testing. He was curious to see exactly how well it was working, compared with its original rating.
He connected it directly (with no intervening battery) to two different 12-volt loads to test it: a 35-watt incandescent light bulb, and a blower rated at 4.5 amps (about 54 watts). Result? “The old PV module passed with flying colors. It easily powered up the light bulb; my Fluke multimeter showed that under a full load of 2.015 amps, the module’s voltage was an impressive 14.93 volts” said Holladay.
The panel tested at an even better performance than when the panel was new..