Most homeowners believe solar panels either work or don’t. But in reality, panels often fail slowly—long before production drops enough for you to notice. A single failing panel can create hot spots, trigger inverter issues, reduce the efficiency of surrounding panels, and even cause systemwide shutdowns if the problem becomes severe.
In Texas, where roofs endure extreme heat, storms, and shifting temperatures, panels degrade faster and experience more stress than in many other states. Catching early signs of panel failure is essential to protecting your entire system and avoiding expensive repairs later.
This blog explains the subtle warning signs of failing panels, why failures happen, and how homeowners can prevent small issues from impacting their entire solar system.
Why Solar Panels Fail Over Time
Solar panels are engineered to last 25+ years, but several factors can shorten their lifespan—especially in DFW’s climate. Before you can recognize early failure, it helps to understand the most common causes.
1. Heat Stress (A Major Factor in Texas)
Solar panels lose efficiency when they get too hot, and the Texas sun pushes panels far above their ideal operating temperature. Over time, this heat causes:
- Thermal expansion
- Cell fatigue
- Material breakdown
- Microcrack spreading
- Delamination
Heat is one of the biggest contributors to panel degradation in the state.
2. Microcracks Inside the Panel
Microcracks form from:
- Hail impact
- Thermal cycling
- Roof movement
- Panel flex during installation
- Poor-quality racking systems
These cracks reduce panel output and often go unnoticed until system performance drops significantly.
3. Moisture Intrusion
Once water enters a panel through cracks, weakened seals, or damaged backsheets, it begins to corrode internal components.
This causes:
- Reduced energy production
- Rapid degradation
- Hot spots
- Internal shorting
Moisture is especially common after strong Texas storms.
4. Damaged Panel Backsheets
Backsheets protect wiring and cells from exposure. With age and heat, backsheets may:
- Crack
- Discolor
- Peel
- Warp
Once this happens, moisture and heat damage accelerate rapidly.
5. Manufacturing Issues
Less common, but defective panels sometimes fail early due to:
- Weak soldering
- Poor lamination
- Thin or fragile glass
- Weak junction box adhesion
Even reputable brands sometimes produce faulty batches.
6. Improper Installation
Installation mistakes create long-term stress on panels. Problems include:
- Over-tightened bolts
- Uneven racking
- Wire tension pulling on connections
- Panels placed too close to heat vents
- Roof penetrations installed incorrectly
Poor installation is one of the top causes of early panel issues that Sunaura Solar discovers during diagnostics.
Early Warning Signs of a Failing Solar Panel
Most failing panels give clear warning signs—if you know what to look for. These signs might not always be visible, but your monitoring system and system behavior often reveal early problems.
1. Sudden Drop in Production on Clear Days
A failing panel typically produces significantly less energy than usual. Homeowners may notice:
- Lower daily totals
- Frequent dips in output
- Inconsistent afternoon production
If one panel begins failing, your monitoring app may show:
- A string performing poorly
- Lower production from half the system (if using optimizers or microinverters)
- Repeated fluctuations in output
Production drops are one of the earliest signs something is wrong.
2. Hot Spots on the Panel Surface
Hot spots occur when a part of the panel overheats due to:
- Microcracks
- Internal damage
- Bypass diode failure
- Debris buildup
- Moisture inside the panel
Hot spots reduce production and accelerate long-term damage. Technicians detect these using thermal imaging during diagnostics.
3. New Inverter Error Codes
Failing panels often trigger inverter issues. Common messages include:
- “Arc fault”
- “Ground fault”
- “Isolation fault”
- “Low voltage”
- “String mismatch”
- “DC overcurrent”
If your inverter starts showing new alerts, it often means one or more panels are malfunctioning.
4. Changes in Panel Temperature Compared to Others
If one panel is significantly hotter than the rest, it is likely failing. Hot panels produce less energy and may be at risk of long-term damage.
5. Visible Panel Damage
From the ground, homeowners may notice:
- Cracks
- Cloudy patches
- Burn marks
- Yellowing
- Milky discoloration
- Moisture under the glass
- Bowed or warped surface
Even small visual changes can indicate internal failure.
6. Frequent System Shutdowns
If your system turns off more often during heat waves, storms, or mid-day production peaks, a failing panel could be the cause. When one panel malfunctions, it may pull the entire system down—especially in string inverter setups.
7. Higher-Than-Normal Utility Bills
If you notice a bill spike and your monitoring system looks off, a failing panel may be to blame. Many homeowners don’t realize their system is underperforming until they see the impact on their electricity bill.
Texas-Specific Causes of Early Panel Failure
Texas weather accelerates panel wear in ways that many states never experience.
1. High Heat + UV Exposure
Extreme UV intensity breaks down protective materials, especially on older installations.
2. Hailstorms
Even when panels don’t shatter, hail can create microcracks or internal cell damage.
3. High Winds
Wind pushes panels, stressing wiring, connectors, and mounting hardware.
4. Heavy Pollen and Dust
Buildup causes hot spots and reduces airflow, leading to heat stress.
5. Rapid Temperature Shifts
Storms often hit after hot days, creating thermal shock on panel glass.
6. Wildlife Interference
Birds, squirrels, and insects frequently damage wiring or nesting around panels.
How to Prevent a Single Failing Panel From Affecting the Whole System
The key to preventing panel failure is proactive maintenance and early intervention. Here’s what homeowners can do.
1. Schedule Regular Solar Maintenance
Annual maintenance is essential, especially in Texas. Professional technicians check:
- Panel health
- Internal wiring conditions
- Connector wear
- Racking stability
- Early signs of microcracking
- Inverter performance
- Roof penetration health
- Hot spots using thermal imaging
Maintenance catches small issues before they escalate.
2. Keep Panels Clean Year-Round
Dirty panels run hotter and degrade faster. Cleaning prevents:
- Heat pockets
- Micro-scratches
- Surface staining
- Moisture-holding grime
- Wildlife debris buildup
Clean panels perform better and age slower.
3. Monitor Your System Regularly
Your monitoring app is your early-warning system. Look for:
- Production dips
- String-level issues
- Outlier panel temperatures
- Unusual alerts
Monitoring allows homeowners to catch failing panels early.
4. Repair Wiring and Conduit Early
Failing panels and wiring issues often go hand-in-hand. Fixing wiring early prevents further panel stress.
5. Schedule Diagnostics After Major Storms
Storms often cause early damage invisible from the ground. After hail or wind events, diagnostics can identify:
- Internal cracks
- Frame stress
- Wiring displacement
- Mounting hardware issues
Texas homeowners should always get storm-season inspections.
When a Solar Detach & Reset Helps Identify Failing Panels
Sometimes, the only way to properly evaluate panel health is through a Solar Detach & Reset (D&R).
A D&R is recommended when:
- The roof needs replacement
- Panels were installed improperly
- Wiring damage is suspected
- Panels show inconsistent production
- Past storm damage is unknown
- The system has a history of repeated issues
During a D&R, technicians:
- Remove panels safely
- Inspect wiring and mounting points
- Repair hidden damage
- Reinstall panels correctly
- Test system performance
This often restores production and fixes long-standing panel issues.
