Solar Panel Inspection After Hail: What Damage Should You Check For?
By Team Faseeh Lall
A hailstorm can pass in minutes, but the damage it leaves behind may affect a solar system for months or years.
The difficult part is that hail damage is not always obvious.
Broken glass is easy to recognize. Small cell cracks, damaged electrical connections, frame stress, mounting movement, or declining production can be much harder to detect from the ground.
A solar array may even continue generating electricity after a hailstorm while one or more modules are performing below normal.
That is why a solar panel inspection after hail should focus on more than visible cracks.
The U.S. Department of Energy recommends visual and electrical inspection after a damaging hail event and notes that infrared, ultraviolet, or electroluminescence imaging may be needed to identify damage that cannot be seen from the surface.
Here is what solar owners should check after significant hail and when professional inspection may be appropriate.
Can Hail Damage Solar Panels?
Yes.
Solar modules are designed for outdoor exposure and are tested for impact resistance, but that does not make them immune to every hailstorm.
The Department of Energy notes that standard IEC hail certification commonly involves testing modules against 25 mm ice balls traveling at approximately 23 meters per second. More severe hail conditions can exceed the basic certification test.
Damage depends on factors such as:
Hailstone size
Impact speed
Wind speed and direction
Module angle
Glass thickness
Module construction
Duration of the storm
Existing condition of the system
A panel can also sustain internal cell damage without its front glass visibly breaking.
That is one of the main reasons a post-hail inspection can be useful.
1. Cracked or Shattered Solar Panel Glass
Visible glass damage is the first thing most owners think about after hail.
Look from a safe location for:
Cracked glass
Shattered areas
Star-shaped impact marks
Chips
Spiderweb cracking
Broken corners
Surface damage around impact points
Severely damaged modules should not be touched.
Cracked glass can expose internal components to moisture and create electrical or safety concerns.
If the system suffered obvious physical damage, DOE recommends making the system safe and performing visual and electrical inspection before normal operation resumes.
Do not climb onto a damaged roof to inspect the panels yourself.
2. Hidden Solar Cell Microcracks
One of the most important types of hail damage may be invisible.
A hailstone can place mechanical stress on the cells beneath the glass and create small fractures called microcracks.
The module surface may still look normal.
DOE's weather-vulnerability guidance notes that hail and other mechanical stresses can produce cell microcracking and that these cracks may require infrared or electroluminescence imaging to locate.
Microcracks do not always cause immediate major power loss.
However, some cracks can expand or electrically isolate parts of a cell over time.
That may contribute to:
Reduced module output
Uneven current flow
Hot spots
Long-term performance loss
A normal-looking panel therefore should not automatically be assumed to be undamaged after a severe hail event.
3. Hot Spots and Abnormal Heating
Physical damage can create areas of abnormal electrical resistance or uneven current flow.
These areas may operate at higher temperatures than surrounding cells.
They are commonly referred to as hot spots.
From the ground, you normally cannot identify a hot spot by looking at the panel.
Infrared thermal imaging can help identify unusual temperature patterns across:
Cells
Modules
Strings
Connectors
Other electrical components
DOE specifically recommends considering thermal or infrared imaging when evaluating hidden damage after damaging events.
Thermal findings still need professional interpretation.
Not every temperature difference means hail damage.
Shading, dirt, bypass diode behavior, electrical faults, and operating conditions can also affect module temperature.
4. Damaged Module Frames
The glass is not the only part of the module exposed to hail.
Inspectors should also check module frames for:
Dents
Bending
Separation
Loose corners
Movement
Damage around clamps
Frame damage can affect how securely the module sits within the mounting system.
Even when electrical production appears normal, structural damage may deserve attention.
Large commercial arrays can require more systematic inspection because individual damaged modules may be difficult to identify visually across hundreds or thousands of panels.
5. Loose Clamps, Rails, or Mounting Hardware
Hail often occurs during severe thunderstorms that may also bring strong wind.
The inspection therefore should not stop at the modules.
Mounting components may need to be checked for:
Loose clamps
Shifted modules
Damaged rails
Missing hardware
Bent components
Structural movement
Corrosion exposed by damage
SAMS MD's existing inspection checklist includes checking mounts, rails, and roof penetrations for stress or shifting.
If the array appears misaligned after a storm, do not attempt to reposition modules yourself.
The mounting system should be evaluated by qualified personnel.
6. Wiring and Connector Damage
Hail itself may strike exposed components, while storm movement or debris can affect wiring underneath and around the array.
A post-hail inspection may check for:
Damaged cable insulation
Loose wiring
Broken connectors
Exposed conductors
Damaged junction boxes
Conduit damage
Moisture intrusion
Burn marks
Corrosion
Electrical damage may not be visible from ground level.
The system may also continue generating despite a partial wiring or string problem.
That is why unexplained performance changes after hail should not be dismissed simply because the inverter is still online.
Electrical testing should be performed by appropriately qualified professionals.
7. Junction Box and Bypass Diode Problems
Each module contains electrical components that help transfer electricity and manage abnormal operating conditions.
These can include junction boxes and bypass diodes.
A hail event may not directly destroy these components, but damage to the module or electrical connections can contribute to abnormal behavior.
Possible signs include:
Reduced module output
Thermal abnormalities
String imbalance
Inverter alerts
Unusual performance patterns
Infrared inspection may help identify abnormal heating associated with some electrical problems.
Further electrical testing may then be needed to determine the actual cause.
8. Roof and Roof-Penetration Damage
For rooftop systems, post-hail inspection should also consider the roof beneath and around the solar array.
Hail can damage:
Shingles
Roof membranes
Flashing
Sealants
Mounting penetrations
Drainage areas
A leak appearing after a hailstorm does not automatically mean the solar installation caused it.
The roofing material itself may have been damaged during the same weather event.
Check safely for signs such as:
New ceiling stains
Interior moisture
Damaged roofing visible from the ground
Debris near the array
Shifted equipment
Do not climb onto a wet or storm-damaged roof to investigate.
Your existing SAMS MD roof-leak guidance also identifies hail and major storms as events capable of affecting panels, mounting hardware, flashing, and roofing materials.
9. Inverter Errors After Hail
After the storm, check your monitoring system and inverter status.
Possible warning signs include:
New error codes
Repeated inverter trips
Reduced inverter output
One inverter producing less than another
Communication failure
Unexpected shutdowns
A hail event can damage modules or electrical components upstream of the inverter.
The inverter may therefore report the effect of the problem even when the inverter itself was not physically struck.
Do not repeatedly reset an inverter that begins faulting after severe weather without understanding why.
A recurring fault should be investigated.
10. A Sudden Drop in Solar Production
One of the most useful checks after hail is your production history.
Compare:
Production before the storm
Production immediately afterward
Similar days with comparable weather
Individual inverter output, where available
String-level data, if your monitoring system provides it
A significant unexplained decline may indicate:
Damaged cells
Failed modules
String problems
Wiring faults
Inverter problems
Monitoring issues
However, lower production immediately after a storm does not automatically prove hail damage.
Cloud cover, debris, outages, or other weather-related conditions may also affect generation.
The objective is to identify an unusual pattern that deserves further investigation.
Visible Damage vs. Hidden Hail Damage
Post-hail damage can broadly be divided into two categories.
Visible Damage
This may include:
Broken glass
Cracked modules
Damaged frames
Shifted panels
Loose mounting equipment
Damaged wiring
Roof damage
Hidden Damage
This can include:
Cell microcracks
Electrically inactive cell areas
Hot spots
Internal electrical faults
String-level performance problems
DOE notes that invisible hail damage can exist even when glass remains intact. It recommends imaging methods such as IR, UV, or electroluminescence after hail events where hidden damage is a concern.
What Tests Can Detect Hidden Hail Damage?
A professional inspection may use different diagnostic methods depending on the system and severity of the event.
Visual Inspection
This is usually the first step.
It can identify:
Broken glass
Frame damage
Mounting movement
Debris impacts
Wiring damage
Obvious roof problems
Electrical Testing
Electrical tests can help identify:
Faults
String abnormalities
Insulation problems
Unexpected voltage or current
Grounding concerns
Infrared Thermal Imaging
Thermal imaging looks for abnormal temperature patterns.
It can help narrow down areas that may require further electrical testing.
Electroluminescence Imaging
EL imaging is especially useful for identifying solar-cell cracks that may not be visible externally.
DOE describes EL imaging as particularly revealing for cell cracking, although it is more time-consuming and costly than basic visual inspection.
Not every hail event requires every type of test.
The inspection scope should reflect:
Storm severity
Visible damage
System size
Performance changes
Insurance requirements
Warranty requirements
Asset value
Should You Shut Down Your Solar System After Hail?
Not every hailstorm requires shutdown.
However, if you can see significant module damage, exposed electrical components, loose equipment, or other obvious hazards, the system should be treated cautiously.
DOE advises that systems with visible damage after hail should be made safe and inspected before normal operation resumes.
Do not touch damaged modules, exposed wiring, disconnects, or electrical equipment unless you are qualified to do so.
If you are unsure about system safety, contact the appropriate solar or electrical professional.
Can You Inspect Hail Damage Yourself?
You can perform basic observations from a safe location.
You may be able to review:
Visible panel cracks
Debris
Shifted panels
Inverter status
Monitoring alerts
Production data
Visible roof damage
You should not:
Walk on the roof after a severe storm
Walk on solar modules
Open electrical enclosures
Disconnect wiring
Test live circuits
Remove damaged panels
Attempt electrical repairs
A professional inspection becomes particularly important when there is visible damage, abnormal production, inverter faults, suspected wiring issues, or uncertainty about system safety.
Should Hail Damage Be Documented?
Yes.
Photographs, monitoring records, inspection results, and repair documentation can be useful for:
Maintenance history
Warranty discussions
Installer coordination
Insurance claims
Comparing future performance
Document:
Date of the hail event
Visible damage
Production before and after the storm
Inverter alerts
Inspection findings
Components repaired or replaced
Coverage for hail damage varies.
DOE recommends understanding what a property's insurance policy covers and whether hail has specific exclusions or claim limits.
Manufacturer warranties and insurance coverage are separate issues, so review the terms that apply to your actual system.
Does Hail Damage Automatically Mean the Panels Need Replacement?
No.
Replacement depends on the type and severity of damage.
A cosmetic mark does not necessarily mean a module has failed.
Likewise, a module that appears normal may still require further testing if performance has changed.
The decision should be based on factors such as:
Physical condition
Electrical test results
Imaging results
Production impact
Manufacturer guidance
Safety concerns
Repair feasibility
Severely broken modules generally require more immediate attention than minor superficial marks.
Solar Panel Inspection After Hail for Commercial Systems
Commercial PV systems can require a more structured post-event approach.
A commercial array may contain hundreds or thousands of modules, making individual ground-level inspection impractical.
Owners may need to combine:
Monitoring review
Visual inspection
Electrical testing
Thermal imaging
Targeted EL imaging
Repair documentation
Warranty coordination
Insurance documentation
Commercial systems may also have stronger financial reasons to act quickly.
A partial failure that looks small as a percentage of the array can still represent meaningful lost generation across a large system.
For systems participating in SREC programs, reduced physical production may also mean fewer qualifying units of generation available to support certificate creation.
How SAMS MD Can Help After Hail
SAMS MD's solar asset management services already include system inspection, performance monitoring, maintenance coordination, installer coordination, and warranty support.
After a hail event, the process can involve:
Review monitoring → inspect visible damage → identify performance changes → determine whether further testing is needed → coordinate the appropriate next step → verify system performance afterward
That is especially useful when the system is still producing electricity but something does not look or perform the way it did before the storm.
Frequently Asked Questions
How can I tell if hail damaged my solar panels?
Look for visible cracks, broken glass, damaged frames, shifted panels, new inverter errors, or an unexplained production drop. Some hail damage, including solar-cell microcracks, may not be visible and can require thermal, electrical, or electroluminescence testing.
Can solar panels have hail damage without cracked glass?
Yes. Mechanical impact can cause internal solar-cell cracking even when the front glass appears intact. DOE guidance specifically notes that hidden microcracks may require IR or electroluminescence imaging to detect.
Should solar panels be inspected after every hailstorm?
Not every minor hail event requires the same level of inspection. Inspection becomes more important after severe hail, visible damage, sudden production changes, inverter faults, or when insurance, warranty, or asset-management requirements call for post-event assessment.
Can hail damage reduce solar panel output?
Yes. If hail damages cells, electrical connections, wiring, or other system components, production may decline. The effect can range from minimal to significant depending on the extent of the damage.
Can I inspect hail damage on solar panels myself?
You can safely review monitoring data and look for obvious damage from the ground. Rooftop access, electrical testing, module removal, and diagnosis of potentially damaged electrical equipment should be handled by qualified professionals.
Does solar panel warranty cover hail damage?
Coverage depends on the specific manufacturer warranty, installation agreement, and insurance policy. Hail damage should not automatically be assumed to be covered. Review the terms for your actual system and document the event and inspection findings.
Final Thoughts
The most important thing to understand after hail is that no visible crack does not necessarily mean no damage.
A proper post-hail assessment may need to consider:
Module glass
Solar cells
Frames
Mounting hardware
Wiring
Junction boxes
Roof conditions
Inverter behavior
Monitoring data
Overall production
Visible damage is only one part of the inspection.
If the system experienced severe hail, shows new faults, or begins producing less electricity than expected, a professional solar panel inspection can help determine whether the problem is cosmetic, electrical, structural, or performance-related.
The objective is not to replace every panel after a storm.
It is to identify actual damage early, make the system safe, coordinate the right repairs, and confirm that normal production has returned.