Solar panel systems will show a reduced ability to absorb sunlight and convert it into solar energy over their lifetime. However, it takes many years for this slow loss of efficiency to occur. Factors that cause this include hot weather as well as the natural reduction in chemical potency of the panels, also known as the “degradation rate.”
A solar panel with a lower degradation rate will produce more energy over its lifetime. Essentially, the lower the degradation rate, the better the solar panel. Solar panel degradation rates depend on the brand as well. As you’d expect, higher-quality panels will have a slower degradation rate than lower-quality panels.
The average solar panel loses 0.8% of its output each year according to a National Renewable Energy Laboratory (NREL) study. However, premium manufacturers offer panels with degradation rates as low as 0.3%, meaning their panels will last much longer compared to the majority of other manufacturers. This makes degradation rate a vital aspect to consider when comparing solar panels during your pre-purchase research process.
