Project Name: Understanding and Overcoming Water-Induced Interfacial Degradation in Silicon Modules
Funding Opportunity: PVRD2
SETO Subprogram: Photovoltaics
Location: San Diego, CA
SETO Award Amount: $588,505
Awardee Cost Share: $83,333
Project Investigator: David Fenning

This project is developing a spatially-resolved characterization methodology to detect the location and amount of water present in photovoltaic (PV) modules and to model any predicted acceleration in performance degradation. The project team is examining the physical underpinnings of these effects by combining first-principles atomistic modeling of the segregation, diffusion, and chemical effects of interfacial water with continuum finite element method modeling of water distribution and its effects. Based on the resulting physical model of a module’s water exposure over time and predicted changes in material properties and power output, the project team plans to develop statistical response surface models to predict a module’s hazard function.


The research team is developing a non-destructive technique to measure moisture inside a solar module. To complement that work, the team is also developing modeling of the ingress of water and its detrimental impact at interfaces in modules, validating the model with experimental data acquired in controlled moisture and heat environments.


This project will create a direct non-destructive method for observing moisture in existing photovoltaic modules. Moisture inside module packaging has been connected to degradation due to delamination, encapsulate degradation, and corrosion of contacts. Having a greater understanding of moisture in modules will help to lower overall degradation of solar modules, helping to lower the levelized cost of electricity produced by photovoltaics.