It's challenging to predict, and even more challenging to design, ways to reduce corrosion of solar panels, because it's highly dependent on material and environmental conditions. Now, Olga Lavrova of the Energy Department's Sandia National Laboratory, has demonstrated a link between corrosion and the risk of arc faults in photovoltaic (PV) systems' electrical connections.

Eric Schindelholz, Olga Lavrova, Rob Sorensen and Erik Spoerke."One of our primary goals is to predict how fast corrosion will occur and what damage it does, given certain environments and materials. This, in turn, gives us information to select the right materials for design or to develop materials for corrosion-resistance for a particular environment," says Eric Schindelholz, also of Sandia. "This is especially important for solar energy systems, which are susceptible to corrosion but are expected to last for decades."

The problem is complicated by the diversity of environmental conditions; for example, humidity and sea salt in coastal regions and high ultraviolet radiation but low humidity in a place like Albuquerque, New Mexico.

An important research technique is bringing PV panels inside and exposing them to much higher concentrations of light or putting them in thermal chambers to simulate the equivalent of years of temperature cycles. These accelerated lifetime experiments can show in six months what could happen over decades. One of Lavrova's projects studies PV modules from different manufacturers. Another uses big data analysis to analyze information from existing installations worldwide.

A team led by Erik Spoerke is working to block corrosion altogether. That team is developing nanocomposite films made from inexpensive materials as barriers against water vapor and corrosive gases. Thin films are not the sole answer. However, Spoerke says that he can envision that a technology "like the one we are developing could be part of a collaborative materials system to help replace glass in next-generation PV applications."