It is estimated that the biggest hailstones can fall at up to 100 miles an hour.
That’s crazy.
Even smaller average hail can reach speeds of over 20 mph.
If you’ve ever been caught in a hailstorm, you’ll know it can be quite painful getting hit by ice falling from the sky. It can get quite scary.
There are plenty of people who experience damage to their property due to hail including solar panels.
As you can imagine, large hailstones have the potential to cause extensive damage to your solar panel array including cracks, smashes, and electrical faults.
If you’re worried about this, then you should start to think about solar panel hail protection.
You’ll be thankful next time you come through a major storm without any damage to your solar system.
Especially, if there is a power outage due to the storm and you need to rely on solar power until things are fixed.
Can Hail Damage Solar Panels?
Yes, hail can definitely damage solar panels. It can cause extensive cracks and smashes leaving you with irreparable damage.
Before you get too worried, small hailstones should not cause any damage to solar panels. As long as you’ve installed high quality equipment, it should be able to withstand even 1 inch diameter hailstones.
All panels should conform to the International Electronic Commission (IEC) minimum impact standards. Manufacturers should pass this test before their product is fit for purpose.
The test states that a 25-mm (1-inch) ice ball shot at it in eleven different points at 23 meters per second should not break the glass panel, power must not drop more than 5%, and it must not leak water.
In general, it is only the very heaviest of hailstorms that fall heavier than this test that starts to wreck solar systems.
For example, check out the size and damage from a recent storm:
Are Solar Panels Delicate?
Solar panels are designed to be hardy outdoor pieces of equipment. They should be able to withstand all weather conditions for decades.
In fact, a study published by National Renewable Energy Laboratory (NREL) found that in a survey of 50,000 solar panel systems, the probability of hail damage was 0.05%. Adding to this, the degradation in performance of panels is less than 1% a year.
You can expect solar panels installed on a house to last 40 years or more!
Of course, there’s always the chance of freak weather events that can crack and smash your solar panels. If you live in an area that sees aggressive hail storms then you should still think about adding hail protectors.
To give you an idea of how strong solar panels are, check out this video:
How Will Hail Damage Affect Solar Panel Performance?
Hail damage will dramatically reduce your solar panel’s performance. Anything that interrupts sunlight hitting the solar cells will directly lead to a drop in efficiency and power output.
The most obvious performance reduction will come from large smashes and cracks to the face of your panel. This is because the solar cells can be completely destroyed and rendered useless.
Even if the solar cells are not damaged and there are surface cracks to the glass, power output will still drop. Cracked glass will obstruct lightwaves from reaching the solar cells meaning there is limited amounts of energy for them to absorb.
You might also find that storms can cause other unexpected issues such as electrical faults. After it has been cracked water might be able to filter into the panel and electrical setup causing a short circuit.
Put simply, any damage to a solar panel will reduce the amount of power it supplies.
How to Spot Solar Panel Hail Damage
It’s not always easy to confirm if hail has damaged your solar panel. Often, they are mounted out of sight on a roof or the damage is not visible to the naked eye.
The first thing to do is attempt a visual inspection to identify any major damage. You will quickly see any white smashes to the glass or surface material. If you can see anything but the deep black color of your solar cell, then it needs further inspection.
Hail damage is not always visible and you will need to rely on other pieces of equipment. Checking your power inverter or charge controller should help you spot any issues. For example, if you notice a significant power drop compared to usual then there could be an issue to attend too.
Adding to this, your inverter should alert you to any serious issues such as low voltage or short circuiting. Most inverters will automatically shut down if they sense a system fault.
Crack are not always visible
One important thing to note is internal damage to solar panels is not always visible. Large hailstones can cause significant destruction to the internal solar cells without exterior damage.
If you are worried about this, then consider installing a solar panel monitoring system. This allows you to monitor and check that your system is working correctly at all times.
How To Protect Solar Panels From Hail
Still worried about hail? Then it’s time to get yourself some solar panel hail protection.
There’s a number of ways to defend your system. Here’s 7 easy ways to protect solar panels from hail.
1. Get a High Quality Panel
Solar panels from reputable suppliers shouldn’t break even when faced with 1-inch hailstone flying at 50mph.
This means any properly constructed panel shouldn’t be damaged by 99% of hail storms. Take the time to check the manufacturer and installer of your solar panels to ensure they comply with industry standards.
It’s always a good idea to check customer reviews to get real feedback from people with the solar panels. That way you’ll know if there’s any common problems to look out for.
2. Coat with Methacrylate or Plexiglass
We already know that solar panels are not fragile objects. Even the glass used to cover the solar cells is reinforced tempered glass. Plus the frames are made of anti-corrosion aluminum.
Even with all this protection, you still might want to think about adding another protective layer to really defend against the elements.
Many people add a layer of plastic known as methacrylate, you might have heard of brand names from this such as plexiglass.
In simple terms, it is a sheet of transparent thermally treated plastic that is lightweight and shatter-resistant. It is quite often used as an alternative to glass.
This ticks all the boxes to work as a solar panel hail protector – transparent, shatterproof, and lightweight.
The only drawback is that it will slightly lower the performance of your panels as it is another layer for lightwaves to pass through.
3. Check the Weather Forecast
Fail to prepare, and prepare to fail.
The best defense against anything is to prepare for what’s about to happen.
It doesn’t take long to keep an eye on the weather each day and it’ll help you spot a storm well in advance.
If you can see a heavy storm on the horizon that might produce hail then you can prepare your solar panels accordingly.
Some people have adjustable mounting systems or covers that they can use during adverse weather.
You are not going to lose too much power by covering your solar panels during a storm, there’s not going to be a lot of sunlight anyway.
Your local or national weather service will usually be able to predict hail storms and will class them as ‘severe’ due to their destructive nature.
Or get a Hail Warning App for your phone so you never miss the signals.
4. Get Moveable Solar Panel Mounts
Did you know that solar panels don’t have to be mounted in a static position?
There’s many reasons you might want to adjust the angle or position of a solar panel.
Firstly, it can help you get a better angle to absorb sunlight.
Plus, it means you can move them into a less vulnerable position in the event of hail.
The best way to mount panels for this is to use pole-mount systems. Then you can tilt them vertically when hail is predicted. In my experience, once mounted it takes about 5 minutes to do with 2 people and a wrench.
5. Angle Your Solar Panels
In most areas of the world, solar panels work best at a 30 degree angle.
Placing your panels at an angle should make them more efficient as you can point them directly at the sun!
Have you ever driven past a large solar farm? The panels are not lying flat on the ground, they’re actually mounted at an angle.
This can help to increase the power output by over 40% in some cases!
It also has the added benefit of reducing risk of hail damage. This is because any hail hitting the panel at an angle won’t deliver such a heavy blow.
It is more likely to glance at the panel rather than make a head on contact.
Solar panels lay flat will be open to the full force of a hailstone as it thunders down from the sky. Think of it a bit like a head on car crash!
6. Get Home Insurance
Your home insurance policy will have an option to insure your solar panels.
In fact, many insurance policies will automatically cover your equipment as it is a part of your home.
Be sure to check with your provider that you are actually covered, don’t just assume you are as this could be a costly mistake.
It isn’t generally too expensive to add solar panel cover onto your policy as risk of damage is quite low.
To be honest, proper insurance cover is the only really solar panel hail protector. You can sleep easy knowing if there is a problem, you can have it fixed without incurring massive expenses.
7. Clean Regularly and Remove Debris
One final tip is to make sure you regularly clean your solar panels.
You can do this yourself, hire a professional, or even use an automated robot!
Cleaning your solar panels is good for your equipment and energy production anyway. It is best to do this at least twice a year, particularly in the spring and fall. Plus make sure to remove any snow!
By keeping them in good condition it will also help them to last longer and reduce risk of damage.
You should be quick to remove any debris that builds up on the surface of your panel. Particularly, anything that may weaken the structure is hit by large hail. Things like small stones or dirt that might get deposited on the surface. If something like this is hit with a larger hailstone it could lead to a crack. Think of it like a hammer and nail.
Bad Ways to Protect Solar Panels from Hail
If you’ve been reading advice on forums, then you’ll see a lot of random advice about solar panel hail protectors.
Some ideas are good, other ideas you should avoid. Let’s go through how NOT to protect your solar panels from hail.
Coverage and Shade
I’ve seen some so-called ‘experts’ tell you to mount your solar panels under shade. They claim that modern solar panels are so efficient that they will still perform well in shaded areas.
Well, this is a load of nonsense…
Yes, a solar panel does still work when shaded but its energy output will be a fraction of what it can achieve in direct sunlight.
Solar panels work by absorbing photons of sunlight to create an electric field. So you need to ensure they are getting peak sunlight as often as possible.
If you’re not going to mount your solar panel in an area that gets direct sunlight then I suggest saving your money.
To be honest, if you think the risk of hail damage is so great that you can’t expose your solar panels then don’t bother at all.
Creating Obstructions Like Wire Mesh
You might be thinking of creating some sort of protective net or mesh using chicken wire.
On the face of it, this doesn’t sound like such a bad idea.
But once again, you will simply be reducing the performance of your solar panels quite dramatically.
To keep hailstones out you’ll need quite a fine wire mesh which is going to cast lots of shadows across your solar panel system.
You might think that plenty of light can still get through, but you’ll still notice a serious drop in performance.
I’ve seen energy output drop by 30% or more with this type of mesh coverage.
It is always best to choose a protection that doesn’t block sunlight and cast a shadow over your solar cells.
Final Thoughts
You should now know how to protect your solar panels from hail.
It is only going to be the very largest hailstones over 1-inch in size that are of concern.
Anything else should just bounce right off!
My best tips are to ensure you are covered by home insurance and buy high quality equipment.
If you are still concerned then think about using a moveable mourning system to tilt your panels vertical during hail. Or add a layer of plexiglass which shouldn’t reduce performance too much.
And remember, start adding permanent coverage or shade, solar cells need direct sunlight to work efficiently!
Thanks for reading.
