Tracker motor fault exposed solar modules during hailstorm in Fort Bend County, Texas

What happened

During a severe hail event in Fort Bend County, Texas, a county with several large utility-scale solar arrays in the southern United States, three neighbouring sites are reported to have executed a pre-storm hail stow protocol, rotating single-axis trackers to a steep angle to reduce direct impact on module glass. Two of the sites reportedly experienced no hail damage. At the third, a section of trackers is reported to have failed to reach full stow angle because a motor did not respond to the command.

Hailstones exceeding four inches in diameter are reported to have struck this area directly, breaking glass on several dozen modules. Rows where stow reportedly completed normally, at this and the neighbouring sites, are said to have sustained no direct hail damage. A review is reported to have traced the damaged section to the location of the motor fault, though this review has not been independently sighted.

Contributing factors

A tracker motor or gearbox is reported to have failed to move in response to the hail stow command, leaving a section of the array at an angle that allowed direct hail impact rather than a glancing strike. Tracker motor maintenance is reported to have been prioritised based on generation yield loss rather than storm-readiness risk.

Lessons learned

1. Tracker motor or gearbox that fails to respond to a hail stow command leaves modules exposed to direct hail impact.
2. Maintenance of stow-critical actuators should be based on storm readiness risk, not only generation yield loss.

More lessons on weather and external hazards, from every incident on the register.

Not yet known

• Equipment model and age
• Cost of the damage
• Downtime of the affected section

This entry is updated when these are reported. Get an alert for the next one like it.

Source

ecoportal.net