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Saw another question on solar panels and it reminded me of one big thing that always made me hesitant to consider them.

We get several hail storms each year and having an expensive glass covered(?) panel facing almost straight up seems like it is asking for trouble. How do people who have solar panels mitigate this risk?

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  • I'd expect the glass to be constructed to mitigate any risk. If the hail is bad enough to (say) break a car windscreen then you may have problems, though. Commented Aug 7, 2010 at 5:30
  • Seems like maybe someone should invent some kind of sacrificial plexiglass layer or something that would be inexpensive to replace if needed.
    – JohnFx
    Commented Aug 7, 2010 at 15:17
  • I guessed from the "several storms per year" that he could live in Austin, and it appears I'm correct. For those that don't know, we get at least one storm per year that will drop 3+" hail over some random section of the city. Very scary, and often nothing you can do to prevent significant damage to anything left outside. Commented Aug 8, 2010 at 1:56
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    @280Z28 Exactly, I've given up on making insurance claims for dents in my car every other year. I just live with them now.
    – JohnFx
    Commented Aug 8, 2010 at 15:37
  • I have installed solar panels on active bombing and target ranges for years. I have seen 20mm direct hits to all sorts of shrapnel impacts to them. Never had one go out do to a hit. Never had a full shatter to the face from hits. A few small chips (fixed like a windshield rock chip). And at most a few milliamps loss in output. All panels 2X4ft 250-300w units. Commented Sep 22, 2016 at 15:16

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Smaller panels are one way to go; see this article Hail Damage and your Solar Panels:

If you decide to install photovoltaic modules and worry about hail damage, there are a couple of things to consider. One of the most important concerns the size of the modules. If the region you live in is subject to frequent or serious hail storms, smaller modules are easier and less costly to replace. Also if a large module sustains damage, it will seriously reduce the power output, or even cause the system to fail completely. The drawback with using smaller modules is that they are often more expensive to install.

But of course there is not much that would withstand very large size hail but then your home insurance should cover the damage (just like the damage that would happen to your car and/or house during one of those hail storms). I do not think it is very expensive to get your solar panels added onto your home insurance policy (if they are not covered already). See this answer too: Do roof solar panels and hail mix?

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Most panels are designed to withstand most ordinary hail. Modern panels rarely use glass.

For such large hail, one option might be to pole-mount the panels, then tilt them up to full vertical when serious hail is predicted (takes about 5 minutes, 2 people and a wrench). This will put the faces out of harms way. You could add some kind of a rail at the top end of the array to protect the top edges from damage.

Of course, if you're getting that kind of hail, you're probably also under a tornado watch or warning.

Be sure to talk to your insurance company, no matter what you do. It is NOT the case that solar panels (or any other major addition) are automatically covered - since they add value to your home. Your insurer will need to increase the value in the policy. In addition, the type of installation makes a difference in whether or not they're considered part of the dwelling or need a separate rider attached to the policy. We just did this, so it's fresh in my mind - part of our system is included in the dwelling portion of the policy, and part is a separate rider.

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    Almost every modern PV module has glass on the front. But they are designed to withstand hail impact: The IEC 61215 test subjects modules to impact from 25 mm ice balls at 23 m/s. Commented Jul 12, 2012 at 17:55
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chicken wire, mounted mounted high and secured on four sides to keep it from bending and touching the glass. This will cut efficiency by a few percent.

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My plan is to build a frame from 2x2x1/8 aluminum angle iron frame that will provide appx 12" overhang on all sides of my array, and securely fasten 1" Mesh T304 Stainless Steel Welded .063" 48" Wide, to the frame, mounting it about 12" above the panels. Panel hail ratings consider hail up to 1" in size. It's unlikely that a 1" hail stone would pass through the mesh with out at least being slowed down by contact with the mesh. Larger hail stones would be unable to reach the panels without breaking into smaller pieces or bouncing off. The 1" mesh would restrict approximately 12% direct sunlight to the panel. For example, if a panel is rated at 320watts max power, you would want to use 280 watts/panel for system sizing calculations. The mesh guard could be easily removed/installed to be used only during the peak storm months, allowing full rated panel output when not in use.

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How about put a hinge at the top edge and some type of pull pin at the bottom edge in the center. When bad weather comes, pull the string attached to the latch and let gravity drop the panel to be vertical and greatly reduce the chance the panel will be damaged or destroyed.

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I was thinking about using a roller garage door, with the motor to open and close. Was thinking to build a frame that the door would fit in and just push a button if you see the panels needs to be protected, then once the threat is over just push the button again...

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I'd go with portable solar panels...Renogy makes them...Sounds like they're easy to set-up and break-down. Which means they fold-up quickly and will fit into a storage compartment in my motor home. This should eliminate the hail storm problem.

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I have seen metal roofing under structures prone to ice accumulation protected with 4x4 treated timber supporting chain link fencing. I've never seen a roofing failure cause by ice or hail in these systems. If big hail is what your worried about, this may be a cheap way to protect the panels.

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Mount 1 inch thick Plexiglas cut 1 inch larger then the panel dimension, over the top of the panel with space between the two. Do not mount the panel to the Plexiglas.

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    1"x48"x96" sheet only $1248.05 eplastics.com/Plastic/… Thast seems a little pricey for the purpose. Commented Feb 5, 2012 at 3:45
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    One inch thick seems a little excessive. I'd go for something thinner and plan to replace it if hail damages it too much.
    – Kris K.
    Commented Feb 5, 2012 at 19:36
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Hinge at bottom to adjust angle ,8-12 inch thin plate mounted on top 50/50 when hail is expected raise the panels to 90deg 4-6 inch overhang will protect front and back.

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    Hail often comes without a lot of warning, and with strong winds. Both of those may not be compatible with a solar panel on the roof with this solution.
    – BMitch
    Commented Aug 19, 2015 at 1:02
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I going to put mesh over my panel and probably use the chargeable battery to serve a motor atchatched to slide it with a switch open or close...another idea don't know if one can attached a back plate to panel and flip it downwards with a reflector mirror like dish that can project UV rays towards upside down panel lol I must google that part up....

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    This is all speculative. It offers no explanation why a mesh is a good idea, then wanders off into non related subject. Commented Apr 27, 2016 at 13:51

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