Solar panels are a big investment, often costing tens of thousands of dollars, so it’s natural to wonder how they hold up against nature’s fury—especially hailstorms. With extreme weather events on the rise, from golf-ball-sized hail in Texas to destructive storms in the Midwest, homeowners want assurance that their solar systems can withstand the elements. In this blog, we’ll explore how solar panels are designed and tested for durability, what happens when hail strikes, and how to protect your investment in extreme weather.
How Solar Panels Are Built for Tough Conditions
Solar panels aren’t fragile glass sheets—they’re engineered to endure harsh environments. Most panels consist of tempered glass, a sturdy frame (usually aluminum), and layers of protective materials encasing the solar cells. Here’s what makes them tough:
- Tempered Glass: The top layer is typically 3–4 mm thick tempered glass, which is four to five times stronger than standard glass. It’s designed to resist impacts and thermal stress.
- Lamination: Solar cells are sandwiched between EVA (ethylene-vinyl acetate) layers, adding flexibility and cushioning.
- Frames: Aluminum frames provide structural support, keeping panels rigid against wind and debris.
Manufacturers test panels to meet international standards like the IEC 61215, which includes hail resistance. The baseline test simulates hailstones up to 25 mm (1 inch) in diameter hitting at 23 meters per second (about 51 mph)—roughly the size and speed of hail in a moderate storm.
Hailstorm Durability: What the Tests Show
To push beyond the basics, some companies and labs conduct extreme hail tests. For example:
- The National Renewable Energy Laboratory (NREL) has fired larger hailstones (up to 2 inches) at panels using compressed-air cannons, mimicking severe storms.
- Leading manufacturers like Tesla, LG, and SunPower often tout panels surviving impacts from 35 mm (1.4-inch) or even 50 mm (2-inch) hailstones at higher velocities.
Results? Most modern, high-quality panels shrug off small to medium hail (1–1.5 inches) with minimal damage—cracks might appear in the glass, but the cells keep producing power. Larger hail (2+ inches) can cause more serious issues, like microfractures or shattered glass, potentially reducing efficiency or requiring replacement. However, such extreme hail is rare, occurring in only about 1% of U.S. storms annually, per NOAA data.
Real-World Evidence
Hailstorms have put solar panels to the test across the U.S., and the outcomes vary:
- Texas, 2021: A massive hailstorm in San Antonio dropped 2-inch hail, damaging cars and roofs. Local solar installers reported that while some older or lower-quality panels cracked, most newer systems sustained only cosmetic damage and kept working.
- Colorado, 2017: A Denver-area storm unleashed 2.5-inch hail, one of the state’s worst in decades. A solar farm near Greeley saw panels with cracked glass, but energy output dropped by less than 5%, according to post-storm assessments.
These cases highlight a key point: Panel age, quality, and installation angle matter. Newer panels with robust designs fare better, and tilting panels (common for optimal sun exposure) can deflect hail more effectively than flat surfaces.
Factors That Affect Hail Resistance
Not all solar panels are equal when facing a hailstorm. Here’s what influences their survival odds:
- Quality: Tier-1 brands (e.g., SunPower, Panasonic) often exceed minimum standards, using thicker glass or reinforced frames.
- Age: Older panels may have weakened glass or degraded seals, making them more vulnerable.
- Mounting Angle: Steeper angles (30–45 degrees) help hail glance off, while flat panels take direct hits.
- Hail Size and Speed: Most panels handle 1-inch hail fine; 2+ inches at high velocity is the danger zone.
Protecting Your Panels from Hail
While solar panels are tough, you can take steps to minimize risk during extreme weather:
- Choose Durable Panels: Opt for models rated for larger hail (e.g., 35 mm or more) if you’re in a hail-prone area like the Great Plains.
- Install Protective Covers: Some companies offer hail guards or retractable shields, though these add cost and complexity.
- Insurance: Standard homeowner’s insurance often covers hail damage to solar panels, but check your policy—deductibles and exclusions vary.
- Maintenance: Regular inspections can catch microfractures early, preventing bigger issues down the line.
What Happens If Panels Get Damaged?
If hail does crack your panels, all hope isn’t lost. Minor damage (e.g., surface cracks) rarely stops energy production entirely—studies show efficiency losses of 1–10% in most cases. Severe damage, like shattered glass or broken cells, might cut output significantly, requiring repair or replacement. Warranties typically cover manufacturing defects for 10–25 years but may exclude “acts of God” like hail unless specified.
Post-storm, have a professional assess the damage. Infrared imaging can detect hidden cell fractures, ensuring you don’t miss underlying issues.
Hail-Prone States: Should You Worry?
If you live in “Hail Alley” (Texas, Oklahoma, Kansas, Nebraska), hailstorms are a fact of life. NOAA reports these states see hail 1 inch or larger 7–9 days per year on average. Yet, solar adoption remains strong—Texas alone added over 10 gigawatts of solar capacity by 2024. Why? The risk is manageable. High-quality panels, proper installation, and insurance provide a safety net, making solar viable even in stormy regions.
In contrast, states like California or Arizona face less hail risk, with fewer than 2 hail days annually, giving panels an easier ride.
Final Thoughts
Can solar panels survive a hailstorm? Yes, most can—withstand small to moderate hail with little trouble, thanks to rigorous design and testing. Extreme hail (2+ inches) poses a bigger threat, but such events are outliers, and damage is often repairable. For homeowners in hail-prone areas, choosing durable panels and securing insurance can tip the scales from worry to confidence.
Solar panels are built tougher than they look, engineered to weather more than just sunshine. So, while a hailstorm might test their mettle, it’s unlikely to knock them out of the game. If you’re considering solar, don’t let hail hold you back—plan smart, and your panels will power through the storm.
