If you have a solar installation or planning to buy one and your location is prone to hailstorms, you should continue reading.
Does hail damage solar panels?
Solar panels need to be placed out in the open to capture the sunlight and convert it to electricity. So, there is not much you can do about the solar panels being exposed to the elements.
Rains, in fact, are actually helpful. It keeps the surface of the solar panel clean by washing away the dust and dirt. Another threat to solar panels is falling branches from nearby trees. You can cut away the branches that are posing a threat to the panels.
Ultimately, it is the hails that can cause serious damage to solar panels. Solar panels and hail storms don’t gel well.
Hails falling on unprotected solar panels can take away the advantage of installing the solar energy system. With heavy initial investment, you would expect it to give you cheap energy for a decade or two or even more. Hails can upset your apple cart in no time.
This doesn’t mean you should not get solar installation or you can do nothing to protect the already installed panels. Read on to learn more about how hails can damage the panels and what you can do to protect them.
What is hail and how damaging is it?
Hailstones are solid precipitation formed when raindrops inside thunderstorm clouds get carried upwards by intense updrafts into very cold regions of the atmosphere. The water freezes into irregular shapes of ice, often in a ball shape. This is different from ice pellets that fall in cold weather.
Hailstones are varied in size – from smaller pebbles to even the size of a baseball. It can weigh anything up to half a pound.
The deadly effect of hailstones is not only from their size and weight. The damage is mostly due to how hard they hit the earth’s surface. Though hailstones are not deadly enough to kill humans or animals, larger ones have the potential to cause serious injuries and damage to properties and crops.
How much damage can hailstones cause to solar panels?
Hailstones definitely have the potential to damage solar panels as they are like sitting ducks in a hailstorm. Panels come with a glass topping to protect the solar cell and the wiring inside.
The stringent quality standards compel manufacturers to subject the panels to some tests to confirm their ability to withstand impacts like hailstones. Most panels can withstand the impact of up to one-inch hailstones.
However, if you stay in places like Colorado, Nebraska, or Wyoming, which get severe hailstorms, you may need to take extra precautions while buying and installing solar panels.
Why do certified panels get damaged in severe hailstorms?
It is the International Electronic Commission (IEC) that sets the standards for the impact test for solar panels. It stipulates that the panels withstand the impact of a 25mm ice ball hitting it at a speed of 23m/sec. As long as the panel doesn’t break, or energy output doesn’t reduce by more than 5%, or water doesn’t leak from the panel, it passes the test.
In countries like Australia, the stipulated size of the hailstone is set higher at 35mm. The hailstones can be much larger than 25mm. So, even certified panels may break in a severe hailstorm.
However, some solar panel manufacturers voluntarily test their panels in tougher conditions. It would be wiser to choose these higher-quality solar panels if you are living in a hailstorm-prone place.
How can hail impact affect solar panel efficiency?
Physical damage is easy to see as the glass covering the solar cell may break. And this is bound to impact the performance of the panel.
Even when the top glass doesn’t break, it can still crack or the connections inside may get damaged. This can also affect the output of the solar panel.
In the effort to make solar panels more affordable, the thickness of solar cells is coming down drastically. Though this will not affect their normal performance, it can make a difference when the hailstones hit them hard. It can either result in total damage or low energy production.
The breaks and cracks can lead to imperfections in the solar panels. This will raise the resistance which will ultimately turn hotspots over time. Hotspot heating can further damage the solar panel.
Moreover, breaks and cracks formed on the solar panel make it more vulnerable to weather conditions, especially dust and rains. Dust will get accumulated under the glass on top of the solar cell, creating a barrier for the sunlight falling on it. Rainwater can seep in and cause further damage.
While it is easy to keep the surface of an unbroken solar panel clean with soap water, it is tough to wash away the dust and dirt collected underneath the glass. All these can reduce the sunlight absorbed by the panel and result in low energy output.
When some of the solar cells in a solar panel are damaged by hailstones, it can lead to a mismatch of cells. If all the cells in a solar panel do not have identical properties, it can affect its performance.
How to confirm the damage in a solar panel?
After a hailstorm, it is advisable to inspect the solar panels. This is essential if the hailstorm was a severe one. A visual inspection would suffice for now.
Check if any of the panels are broken, cracked, or irregular in any way. You need not get too close to panels either. You would be able to see these defects from a distance. In fact, the smaller cracks are better identifiable from a distance as the light reflects imperfectly on cracked solar panel surfaces.
In case everything seems fine on the visual inspection, you can move on to the inverter. If there are any damages, the red light in the inverter will light up.
Sometimes the earthing done on the solar system may get damaged or the power generated would be less or nil. Despite everything looking normal and the sun shining bright, if the solar system is not generating electricity, then something is definitely wrong. You need to contact the service center for further inspection and repairs if required.
How to protect solar panels from hailstones?
Solar panels are fragile, being made of glass and thin wafers of solar cells. Naturally, they are damaged when bigger hailstones hit them.
So, what can you do about it? It is not practical or cost-effective to replace the panels after every hailstorm.
Here are some suggestions and tips to protect your solar panels from hail damage.
1. Choose higher-quality panels
While most solar panel manufacturers stop with the minimum standard test, others go the extra mile to make better quality panels that will pass higher endurance tests. Based on the average size of hails in your location, choose the panel.
Amorphous photovoltaic panels or thin-film panels do a better job at withstanding severe hailstorms. The reason is simple. They do not have a glass covering; they have flexible plastic.
2. Use methacrylate plates
The glass cover on a regular silicon crystal solar panel makes it vulnerable to breaks and cracks. By placing methacrylate plates on top of the glass cover can strengthen the solar panel against hail damage. However, before attaching methacrylate plates, you need to make sure that the glass plates are not already broken. The methacrylate plates are the best cover for solar panels.
3. Use plexiglass protectors
Just like methacrylate plates, plexiglass also offers extra protection to the solar panels. One-inch thick plexiglass that is a tad bigger than the solar panel will do the job efficiently as a solar panel protective cover. Ensure that the plexiglass is fixed with a gap in between to avoid heating up.
4. Prepare for the hailstorm
All you need to do is listen to the weather forecast to know that a hailstorm is coming. If you have an adjustable mount for the solar panels, you can tilt the angle in such a way that the hailstones won’t hit the panels. Or you can cover the panels with a protective sheet.
5. Choose movable mounts
If you live in the hail belt, it is better to choose mobile mounts for panels. When you become aware that a hailstorm is coming, you can just push them to a safer place. Once the storm clears, you can bring them back.
6. Fix the panels out of hail’s way
Most professional solar installers know the angle of fall of hailstones if you live in the hail belt. Installing your solar panels away from the path of hails can help you avoid the damage. Fortunately, this is also ideal for maximum exposure to sunlight.
7. Install panels in shades
The latest solar panels work as efficiently in shaded areas as they do in full sunlight. The indirect sunlight is enough for them to generate electricity. However, the shade can prevent solar panel hail damage.
8. Use robots for cleaning
Technology comes to your aid in managing the debris created by hailstorms. If you allow it to remain on the panel surface, it can cause more damage. It may not be easy to clean the panels after every hailstorm. Having a robot handy can help. They use minimum water to wash away the remnants of hailstones.
9. Affix a wire gauge
This is the cheapest and most efficient solar panel hail protector to protect solar panels against hailstones. The wire gauge can do its job of protecting solar panels without obstructing the sunlight.
To learn more, see our article on eight common problems with solar panels on roofs.
All the suggestions listed above can protect your solar panels efficiently but some of them may not be feasible for you to adopt. Choose the method that is most suitable for your location, budget, and circumstances.
Protecting your panels can save you unnecessary expenses from replacing the panels and interruption in energy generation.