In-Field and Laboratory Hail Study Quantifies Stow Effectiveness to Support Solar Plant Extreme Weather Mitigation Strategies

SAND CITY, Calif., April 10, 2025 /PRNewswire/ — GroundWork Renewables, Inc. has been recognized at the 2025 National Renewable Energy Laboratory (NREL) Photovoltaic Reliability Workshop (PVRW) for its innovative research quantifying various approaches to hail mitigation. The company’s study, the first of its kind, provides field measurements of hail impact energy reduction at various tracker stow positions and validates these findings through laboratory testing.

The research was conducted by lead authors Travis Morrison and Colin Silleurd with the cooperation of Recurrent Energy using the GroundWork® Hail Event Monitoring and Reporting service at Recurrent Energy’s North Fork Solar Project, a 120 MW solar plant in Kiowa County, Oklahoma. Findings were validated at GroundWork’s PV Test Lab in Albuquerque, New Mexico. GroundWork’s monitoring service offers the most accurate in-situ data, quantifying the reduction in hailstone kinetic energy when solar tracker modules are stowed, and at what angle, ahead of severe weather. This data is crucial for evaluating the effectiveness of defensive stow strategies in reducing hail damage to photovoltaic (PV) modules.

Mike Arndt, President of Recurrent Energy’s North America business, highlights the importance of the study, stating, “Hail has been a significant, and increasing, challenge for utility-scale solar installations. Effective mitigation strategies are vital. At Recurrent, we are prioritizing resilient plant designs and operating procedures. GroundWork’s solution helps us quantify and verify our assets’ resilience.”

While previous laboratory simulations have modeled hail impact on PV modules, real-world data has been scarce. Ann Will, CEO of GroundWork, states “GroundWork’s study is the first to measure hail impact energy in an operating solar plant at both horizontal and plane-of-array (POA) stow positions, providing empirical data that strengthens industry-wide risk assessments and mitigation strategies. Our unique ability to take and analyze both field and lab data will better enable our clients to insure projects in hail-prone regions, as well as optimize stow strategy.”

Key Findings:

• Kinetic Energy Reduction: Significant reductions in kinetic energy and impact count were observed when PV modules were stowed, validating the effectiveness of mitigation strategies.

• Field vs. Lab Data: Comparison between field measurements and lab models showed alignment in energy dissipation trends, boosting confidence in predictive modeling.

• Enhanced Impact Models: Laboratory testing revealed more accurate models over simple elastic collision models for hail impact at different angles, improving predictions for probable maximum loss (PML) assessments.

• Storm Microphysics Insights: Analysis of hail fall angles and velocities offered new insights into storm behavior and its effect on impact forces.

• On-Site Monitoring: On-site monitoring proved essential for capturing real-world environmental variables that affect PV module resilience.