How to Tell if a Solar Panel is Wearing Out

Given the continuous exposure of the day to harmful sunlight, it is not surprising that solar panels will degrade over time and lose some effectiveness.Just as the sun fades the brightly colored billboard and dries the wooden dock, it slowly damages the electrical connection and reduces the electrical output of the photovoltaic cells in a measurable way.According to the forecast of the National Renewable Energy Laboratory,Less than 1% pounds per year.By testing when solar panels age, users can determine if their equipment has worn to an operational level (see reference 1 ).When PV modules are relatively new and operate at peak levels, their baseline performance readings are collected.Modern solar system with networkReports based on analytical software that allow the user to identify electrical outputs that are suddenly reduced from baseline measurements (see reference 1;Reference 3, Chapter 1, page 4 ).Visually check the panels to confirm that the surfaces are clean and intact and that they can be free from direct sunlight.Some measurable reductions in electrical output are temporary, easy to correct, and do not signal panel wear.By testing the inverter or smart inverter assembly, it is confirmed that the solar panel itself is the cause of the decline in power generation.Photovoltaic cells typically exceed inverters that convert DC power to AC power and allow fluid integration into the grid (see refs 3, Chapter 1, page 6;Reference 4).Compare the current DC electrical output of the PV assembly with the baseline number.Data from the National Renewable Energy Laboratory show that the performance of typical solar panels will decline between the two.5 and .7% per year, although some models were reduced by more than 9% in the first year alone (see ref 5, page 1 ).These figures reflect the performance of the old PV panels tested after several years of exposure, so a new generation of PV modules may wear out at a slower rate.