What You’ll Learn
Introduction
- How solar panels are tested for hail, wind, and snow before they reach your roof
- What the IEC and UL testing standards actually require
- How solar panels perform in real-world severe weather events
- What happens during a power outage with and without battery backup
- How homeowners insurance typically covers solar panel storm damage
If you live in the Northeast, storms are part of life. Nor’easters, summer thunderstorms with hail, ice storms, and heavy snowfall are all routine across Pennsylvania, New Jersey, and Delaware. If you are considering putting solar panels on your roof, wanting to know how they hold up in severe weather is a reasonable and important question.
The short answer is that solar panels are engineered and tested to withstand conditions that significantly exceed what typical Northeast storms produce. The long answer involves understanding what testing standards require, how panels and mounting systems are designed, and what the real-world track record actually looks like. This guide covers all of it.
How Solar Panels Are Tested for Severe Weather
Every solar panel sold in North America must pass a series of rigorous testing protocols before it can be installed. Two international standards govern the testing: IEC 61215 (performance and durability) and IEC 61730/UL 61730 (safety). These tests simulate decades of environmental stress in a matter of weeks.
Hail Testing
The hail impact test under IEC 61215 requires panels to survive a 25mm (approximately 1 inch) ice ball fired at 23 meters per second (approximately 51 mph). This is the minimum standard. Many manufacturers test to more demanding protocols, using larger ice projectiles to demonstrate performance in severe hail regions.
Panels certified to UL 61730 have been tested to withstand hailstones ranging from 1 to 3 inches in diameter at speeds up to approximately 88 mph. For context, most hailstorms in the PA, NJ, and DE region produce hailstones well under 2 inches.
Wind and Mechanical Load Testing
The IEC 61215 standard requires panels to withstand a minimum mechanical load of 2,400 Pascals (50 pounds per square foot), tested in both positive (front) and negative (rear) loading. This simulates both wind pressure pushing against the front of the panel and wind suction pulling from behind, which is the more common failure mode in high-wind events.
Many residential-grade panels are rated for 5,400 Pa or higher, which corresponds to wind speeds significantly above what Northeast storms typically produce. The testing involves three full loading cycles with continuous electrical monitoring to ensure no internal connections are broken.
An additional dynamic mechanical load (DML) test under IEC 62782 simulates 1,000 cycles of push-pull loading at 1,000 Pa, specifically designed to replicate the sustained buffeting that occurs during hurricane-force or extended high-wind events.
Snow Load Testing
Snow load capacity is part of the same mechanical load testing. Panels rated for 5,400 Pa can support substantial snow accumulation without structural damage. In practice, snow typically slides off solar panels relatively quickly due to the smooth tempered glass surface and the tilt angle of the installation. Moderate snow cover temporarily reduces production but causes no damage to the panels.
Temperature Extremes
IEC 61215 requires thermal cycling tests that subject panels to temperatures ranging from minus 40 degrees Celsius to plus 85 degrees Celsius. This range far exceeds the temperature extremes experienced in the Mid-Atlantic region. Humidity-freeze testing further evaluates the panel’s ability to withstand freeze-thaw cycles, which is particularly relevant for Northeast climates.
Real-World Performance in Severe Weather
Testing standards tell you what a panel is designed to survive. Real-world data tells you what actually happens.
The NREL Hailstorm Case
One of the most cited real-world data points comes from the National Renewable Energy Laboratory (NREL) facility in Golden, Colorado. In 2017, a significant hailstorm struck the facility. Out of 3,168 solar panels on site, exactly one was damaged. That is a 99.97 percent survival rate in an actual severe hailstorm.
Northeast Storm Experience
In the PA, NJ, and DE region, the most common severe weather threats to rooftop systems are high winds (from nor’easters and summer thunderstorms), hail (typically 1 inch or smaller), and heavy wet snow. Residential solar installations across the region have a strong track record of surviving these events without damage.
When storm damage does occur to solar systems, it typically involves the mounting hardware or racking system rather than the panels themselves. Improperly installed racking, corroded fasteners, or undersized mounting hardware are the most common failure points. This is why installation quality and the experience of your installer matter as much as panel specifications.
What About Flying Debris?
The most unpredictable storm damage comes not from wind acting on the panels directly, but from airborne debris. A fallen tree branch or wind-borne object striking a panel can crack the glass, just as it could crack a window or damage roofing material. No amount of panel engineering can prevent impact damage from a large object at high velocity.
The good news is that solar panels sit flush to the roof surface (or very close to it), which means they present a minimal target profile for airborne debris. They also add a layer of physical protection to the roof surface itself, shielding the roofing material beneath them.
Solar Panels and Power Outages
This is one of the most commonly misunderstood aspects of solar during storms. A standard grid-tied solar system without battery backup will not power your home during a grid outage.
This is not a design flaw. It is a safety requirement. When the grid goes down, utility workers repair power lines with the expectation that those lines are de-energized. A solar system continuing to export power to the grid during an outage would create a dangerous condition for repair crews. This safety protocol is called anti-islanding, and every grid-tied inverter is designed to comply with it.
If uninterrupted power during outages is important to you, the solution is a solar system paired with battery backup. A battery system allows your solar panels to continue operating during an outage by disconnecting from the grid and powering your home independently. The battery stores excess solar production during the day and provides power through the night or during extended cloudy periods.
Insurance and Solar Panel Storm Damage
Solar panels attached to your roof are generally covered under your existing homeowners insurance policy as part of the dwelling structure. This means storm damage to your panels is treated the same way as damage to your roof, windows, or siding.
There are a few things to verify with your insurance provider after installing solar. Confirm that your policy limits are adequate to cover the replacement cost of the solar system on top of your existing dwelling coverage. Some policies may need an adjustment to the coverage amount. Ask whether your insurer requires a specific endorsement or rider for solar panels. Most major insurers do not, but it is worth confirming. Understand your deductible terms, as they apply to solar damage claims the same way they apply to any other storm damage claim.
If your system is leased or under a PPA, the system owner (the leasing company) typically carries their own insurance on the equipment. Confirm this with your solar provider.
What You Can Do to Minimize Storm Risk
Most storm damage to solar systems is preventable through proper installation and basic maintenance. Work with an experienced installer who uses mounting hardware rated for your local wind and snow load requirements. Ensure your roof is in good condition before installation, so the mounting system has a solid substrate. Keep nearby trees trimmed so that branches do not overhang the array. And schedule periodic inspections to check for corrosion, loose fasteners, or other wear on the mounting hardware.
The panels themselves require virtually no storm preparation. They are designed to be outdoors, exposed to weather, for 25 years or more. Your job is to make sure they are installed correctly and that the roof and mounting system supporting them are maintained.
How Sunwise Can Help
Sunwise Energy installs solar systems across PA, NJ, and DE using mounting hardware and installation practices rated for Northeast weather conditions. Our installations are engineered for the wind, snow, and storm loads specific to your location.
If severe weather performance is a concern, our team can walk you through exactly how your system will be designed and installed to handle whatever the Northeast throws at it.
Storm Durability FAQs
Can solar panels survive hail?
Yes. Solar panels certified to UL 61730 and IEC 61215 standards are tested to withstand hail impacts from ice balls ranging from 1 to 3 inches in diameter traveling at speeds up to approximately 88 mph. The minimum standard requires surviving a 25mm (1 inch) ice ball at approximately 51 mph. In real-world testing, NREL found that 99.97 percent of panels survived a significant hailstorm at their Colorado facility.
What wind speeds can solar panels handle?
Solar panels are tested to withstand mechanical loads of at least 2,400 Pascals (50 pounds per square foot), which corresponds to wind speeds well above what most Northeast storms produce. Many residential panels are rated for loads of 5,400 Pa or higher. The mounting system and installation quality are equally important, as wind damage typically involves the racking system rather than the panel itself.
Does homeowners insurance cover solar panel storm damage?
In most cases, yes. Solar panels attached to your roof are typically covered under your homeowners insurance policy as part of the dwelling structure. Confirm coverage with your insurer after installation, verify that policy limits account for the system’s replacement cost, and understand your deductible terms.
Do solar panels work during a power outage?
A standard grid-tied solar system without battery backup will shut down during a grid outage. This is a safety requirement that protects utility workers. Solar systems paired with battery backup can continue to power your home during outages by operating independently from the grid.
Can heavy snow damage solar panels?
Solar panels are tested for snow loads as part of their mechanical load certification. Panels rated for 5,400 Pa can support significant snow accumulation. Snow typically slides off panels naturally due to the smooth glass surface and the panel tilt angle. Moderate snow cover temporarily reduces production but does not damage the panels.
