A Novel Method to Prevent Potential Induced Degradation (PID) of Photovoltaic Modules During Manufacturing or After Field Installation

As solar cells continue to become more cost and energy efficient, photovoltaic modules generate increasingly greater amounts of power at increasingly higher voltages. Potential induced degradation (PID) is the deterioration of a PV cells capability to generate power due to harmful leakage currents that neutralize its sunlight absorption regions. PID is worsened by high voltages, high temperatures, and humidity, and power losses can take several months to a few years to become noticeable. PID can be prevented by disrupting the surface conductivity path of the leakage current. This is typically accomplished by modifying the modules laminating film or cells anti-reflective coating during manufacturing, or by installing grounded micro-inverters to each module. While solar inverters are necessary to convert the direct current produced by PV modules to alternating current for grid consumption, micro-inverters are significantly more expensive to install and notoriously difficult to maintain. Consequently, there is need for an aftermarket alternative that is both convenient and universally applicable. Researchers at ASU have invented a surface treatment that prevents PID by applying a 2 cm border of transparent hydrophobic resistance coating (like Teflon) or installing a thin layer (