Can Hail Damage Solar Panels? Everything You Need To Know
VeloSolar • Updated on March 13, 2023 • [rt_reading_time postfix=”minute”] read
VeloSolar • Updated on March 13, 2023 • [rt_reading_time postfix=”minute”] read
Hail storms caused over one billion dollars of damage in the US in 2022. Texas and Colorado bore the brunt of the damage, but southern states were not immune. Using data from the Federal Emergency Management Association (FEMA), MoneyGeek found that Georgia had an average of 62 hail events per year between 2018 and 2021, resulting in over $40 million in damages.
With the number of severe weather events on the rise and storm seasons getting longer, it’s no wonder that one of the most common questions we hear from potential customers is can hail damage solar panels installed on my roof?
The good news is that while modern commercial solar panels aren’t indestructible, they are extremely rugged and can withstand most hail storms. Want to learn more? Read on.
Hailstones are solid pieces of ice that form inside thunderstorms. They’re created when raindrops are lifted by updrafts into the cold atmosphere and then freeze. They grow in size as they collide with raindrops and the liquid freezes on the hailstone’s surface. Hailstones fall to the earth when either the updraft weakens or it can no longer support the weight of the stone (in other words, gravity takes charge).
It’s this fall to earth that can cause significant damage. Small hailstones that are less than an inch in diameter typically fall at a rate of 9 to 25 miles per hour. Large hailstones between 1 and 1.75 inches in diameter can fall at a rate of 25 and 40 miles per hour. Hailstones produced by a supercell can reach upwards of 4 inches in diameter and fall to earth at over 70 miles per hour.
The largest hailstone on record in the US fell in Vivian, South Dakota in July of 2010. It was a stunning 8 inches in diameter and weighed nearly 2 pounds. While certainly one for the record books, such large hailstones aren’t common – most run around 3/4 of an inch in diameter.
Nevertheless, at these sizes and speeds, it’s easy to see why hailstones can cause so much property damage and even be deadly to humans and animals.
If your home, car, or commercial property has been damaged in previous hail storms, it’s understandable that you’d be nervous about the ability of your rooftop solar panels to withstand this type of severe weather.
Indeed, if you’ve made a significant investment in renewable energy, the sound of hail stones bouncing off a brand new solar array could make even the most steadfast person cringe in horror.
Traditional solar panels are made up of a series of silicon wafers, or solar cells, that are assembled into rows and columns. Conventional panels are rectangular in shape and come in standard sizes of 60, 72, and 96 cells. Whether they’re made of monocrystalline or polycrystalline solar cells, each panel is covered by a protective sheet of tempered glass that’s thick enough to withstand moderate hail storms. But even so, hail can physically damage your solar panels.
In the aftermath of a severe hailstorm, small cracks or scratches may be found in that protective glass, and depending on the severity of the impact, the solar cells themselves could be damaged.
The good news is that solar industry manufacturers conduct extensive testing to ensure their products can withstand a variety of extreme weather events, including hailstorms and high winds. Solar panels are designed to last 25 years or more, and since, by their very nature they’re designed to be outside in the elements, they have to be rugged.
So, while the answer to the question can hail damage solar panels? is yes, in reality it doesn’t happen all that often.
Thanks to careful design, damage typically occurs only during the most extreme weather conditions.
Plus, different solar panel manufacturers optimize for different performance factors. That means you have options when selecting which brand and type of panels you want to use. Your local solar partner will recommend high quality solar panels that not only meet your energy goals, but are also best suited for the unique nature of your region’s weather.
Here are a few things to keep in mind as you’re working with your solar provider.
Most monocrystalline and polycrystalline solar panels are rated to withstand 25 millimeter (0.98 inches) diameter hail falling at 50 miles per hour. Flexible thin film panels have a lower hail rating due to the nature of their construction.
Underwriters’ Laboratories (UL) and the International Electrotechnical Commission (IEC) have each come up with a hail ratings system based on impact tests they’ve conducted.
If your business is in a hail-prone region, you’ll want to look for top tier solar panels that have either a UL 61730 rating or an IEC 61730 rating, as these have been deemed those most resistant to hail damage. In testing, panels with these markings have withstood 1 to 3 inch diameter hail traveling as fast as 88 miles per hour. Storms that produce larger hail traveling at faster speeds are extremely rare.
The UL certification is most common in the North American market, while the IEC is a standard elsewhere in the world. You may find both markings on your solar panels.
As long as we’re talking about ratings, you also want to look for panels that have an IP68 rating, which indicates that it’s both waterproof and dust-proof. IP68 is a common standard used by most conventional solar panel manufacturers.
If you’re looking for something to further protect your solar panels from severe weather, both hard shell and padded fabric temporary covers are available on the market. But, they have a lot of downsides, not the least of which is they need to be manually placed prior to a storm and then removed again once it’s passed.
While they can protect your solar panels from damaging hail, every minute that your panels are covered is a minute they’re not generating electricity for you. While an option for some smaller solar installations, they aren’t ideal for larger commercial rooftop solar arrays. Not only would you have to invest considerable time covering and uncovering each panel, it’s likely not worth the risk to the team up on the roof as a severe storm approaches – especially if you’ve opted for UL 61730 or IEC 61730 certified panels.
Another option you could consider is adding a layer of methacrylate to your solar panels. Methacrylate is an inexpensive spray-on monomer that can provide some additional protection against impact damage. This is not something you’ll want to apply yourself. If too much is applied, it can impact your panel’s ability to absorb sunlight; conversely, too little of the monomer won’t provide enough protection. Always check with your solar provider before you apply any type of coating to your solar panels. You’ll also want to make sure that adding a coating like methacrylate won’t void your solar panel warranty.
There is a whole science to calculating the proper angle at which solar panels should be installed. The amount of energy your solar panels are able to collect depends, in part, on the angle at which the light passes through them. This means that the angle at which a solar panel is mounted on the racking system is incredibly important.
Identifying the optimal angle for the panel, which is usually somewhere between 30º and 45º in the northern hemisphere, is key to maximizing the amount of light captured, which in turn maximizes the efficiency of the panel.
The angle is also important when it comes to managing precipitation. When calculating the angle of a solar panel installation, your provider will also consider the angle at which snow, rain, and even accumulating hail will quickly slide off the panels. Not only will this help prevent the added weight of the precipitation from damaging your solar panel system, but it will also ensure that you’re back to peak electricity production as soon as possible after the storm.
Unless the solar cells or other electronics in a solar panel are significantly damaged during a hailstorm, the panel itself will continue to work. Cosmetic scratches, for instance, won’t impact the performance of a solar panel.
But, it’s critical that you conduct ongoing maintenance and perform (at minimum) an annual inspection of your solar system. A reputable solar provider, like Velo Solar, can provide operations and maintenance (O&M) services to ensure your solar power plant is in good working order. O&M services typically include a thorough visual inspection of the solar panels, the racking system, and the other critical components of your solar system.
An inspection in the aftermath of a severe hailstorm can check for damage to the solar panels themselves, their frames, and the racking system, as well as remove any debris that may have fallen on the array during the inclement weather event.
Having your provider monitor the performance of your system is another way to quickly identify potential issues, including damage to your solar panels, before small problems become a crisis. If, for example, they see a drop in efficiency or production in the aftermath of a storm, they can send an expert out to diagnose the issue.
If not repaired, hail impact damage can, at minimum, reduce the efficiency of your solar energy system. The cracks and scratches act like little shades, reducing the amount of sun your solar panels can absorb.
Perhaps even more importantly, hail damage can shorten the life of a solar panel. Those cracks can allow water, moisture, and debris to penetrate the surface of panels, causing more significant damage to its internal components.
Additionally, hot spots can form near cracks in the glass, which could result in a malfunction or, in the worst case scenario, could potentially lead to a fire.
Regular maintenance will give you peace of mind that your solar energy system is safe and performing as intended.
Of note, if your solar system is under a power purchase agreement, the solar developer is responsible for monitoring, repairing, and maintaining the panels.
Most solar panel warranties don’t cover hail damage and those that do have a very narrow scope. If your business is in a hail prone region, your solar partner will recommend UL 61730 or IEC 61730 certified panels, and they’ll be able to explain the extent of your coverage for weather related damage.
You’ll also want to have a conversation with your commercial insurance provider to understand what is and isn’t covered under your existing policy. They may recommend changes or additions to ensure your solar array is adequately protected.
Since most solar panels are made to withstand most hailstorms, fears over severe weather events shouldn’t keep you from investing in clean, sustainable renewable energy.
Velo Solar will design a solar system that is tailored to meet your needs and stand the test of time – and mother nature. Plus, with an O&M agreement, they’ll be there after the sale to ensure that any hail damage is dealt with quickly so that your solar panels will help power your operations efficiently and effectively.