Surface Treatment For Preventing Potential Induced Degradation of Photovoltaic Modules


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 cell’s 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 module’s laminating film or cell’s 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 (<100µm) of fused quartz glass inside the module frame. This surface treatment can be applied or installed at any point in a solar module’s lifespan. During manufacturing, the quartz glass boundary can be infused within the usual soda-lime glass cover, or the coating can be sprayed around the frames of modules that are currently in use or sitting in storage. This surface treatment has the same effect on PID as installing micro-inverters but costs considerably less, saving both time and money for manufacturers and consumers.

Potential Applications

  • PID Prevention
  • PV Modules
  • Solar Cells

Benefits and Advantages

  • Convenient – Can be as easy to apply as spraying an aerosol can.
  • Inexpensive – Costs substantially less than micro-inverter alternatives.
  • Retrofit – Can be employed on PV modules already in operation as well as those being manufactured.

For more information about the inventor(s) and their research, please see

Dr. Mani's directory webpage

Dr. Stuart Bowden's directory webpage

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Energy & Power

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