The lifetime of solar panels and inverters used in installations is often a key factor for investors. Scientists tested whether the data provided by module manufacturers is correct.
Service life photovoltaic panels this is an issue that often puzzles investors. Manufacturers often guarantee that their equipment will have an efficiency of 80 percent after 25 years of operation. Customers must take their word for it, and if modules are found to degrade faster, they will face losses.
Scientists at the National Renewable Energy Laboratory in Colorado have looked at the degradation of photovoltaic modules. They purchased 834 solar panels available on the market in 2016-2018. They installed them in locations with different climatic conditions – in New Mexico, Colorado and Florida.
In total, 13 different types of modules were tested, which were produced by seven different manufacturers. The panels were examined at the beginning of the experiment, and then each year their parameters were compared with the modules that spent this period in a shaded, air-conditioned room.
How we read in PV Magazine, in most cases, module degradation rates stabilize after three to four years. It should come as no surprise that panels installed in the hot and humid subtropical climates of Florida degraded faster than those that operated under lighter conditions. Nevertheless, the researchers note that a larger sample would be needed to validate this hypothesis.
The test result may be a bit disturbing. 26.1 percent of the tested modules exceeded the limits of degradation guaranteed by the manufacturer, which means that it is progressing faster than the warranty says. At the same time, 56.5 percent. panels tested will likely hold more than 80 percent. initial power even after 30 years of operation, as long as the degradation rates do not change in the future.
Karol Kołtowski, journalist of Gadgetomania