Over the years there have been many engineering advances to solar technology that have made them more efficient and more durable.
However, many people still aren’t clear about how much weight solar panels can hold. Homeowners know that you need to make periodic trips up onto the roof for one reason or another and you might be unsure you can step on them or support the weight of Christmas lights or any number of other things.
Standard roof-mounted solar panels have a capacity of 50 pounds per square foot with a maximum capacity of 75 pounds however, you should avoid walking on or placing objects on top of your panels as it can cause damage and blocks sunlight.
Solar panels are definitely more durable than they once were, but they still have limits to what they can handle and there are some things you should consider before attaching things to your panels that may block the photovoltaic cells.
Can You Walk On Solar Panels?
Typically, you will want to avoid walking on solar panels since it blocks sunlight from reaching the photovoltaic cells which reduces efficiency, damages the cell surface area of a module, and impacts structural integrity.
Constantly walking on solar panels can cause scratches and abrasions to the surface of the cells, which could lead to an increased rate of efficiency degradation.
If you must walk on top of solar panels then do not put any weight over 50 pounds per square foot and be very mindful about your footing as it can cause irreparable damage to a module if stepped on with too much force or for extended periods of time.
Try to walk on the edges of the module rather than in the middle to avoid putting too much weight on one particular area.
What Are The Risks To Walking On Solar Panels?
Walking on most rooftops is already a cumbersome and awkward task, but walking across roof-mounted solar panels adds some additional challenges:
- Solar panels are smooth and offer little traction.
- Walking on solar panels can cause scratches and micro-fractures which affect the output of a module.
- If you’re blocking the sun during peak daylight hours, you are limiting your panel’s efficiency.
- Added weight and stress to areas of your roof.
- If you’re roped off or carrying equipment, it could become tangled or lodged under the panels which could loosen or bend the framework or pull on wires.
If going onto your roof it’s always best if you can rope yourself off and wear proper footwear that grips well. Maneuvering around solar panels adds some hazards and you will need to make sure any rope or other harnessing doesn’t tangle on your solar panel racking.
Check out the work boots you’re wearing and make sure they are properly laced up and don’t have any rocks embedded in the treads.
I go in to a lot more detail about walking on solar panels over here in this article.
Is It Okay To Attach Christmas Lights To Solar Panels?
Generally, attaching objects such as Christmas lights to solar panels won’t damage or limit the functionality of solar panels. However, ensure that nothing is blocking the photovoltaic cells of the panels and is only attached to the solar panel framework.
There are a couple of things to remember when attaching Christmas lights or any other object onto your solar panels:
- Attach the cords and wires as far away from edges of roof-mounted modules, wiring, edge trusses, and penetrations through framing members. This will reduce strain on connections which could lead to loosening with time.
- Do not attach any object with a weight over 50 pounds per square foot.
- Be mindful of your footing as it can cause irreparable damage by stepping on the modules.
- Make sure your ladder is pressing up against the side of solar panel framing since this can bend or loosen it or create stress points on the solar panel.
- Do not use any object that will block sunlight from reaching your panels during peak daylight hours. This will reduce efficiency and impact panel life expectancy.
This list really only applies to string lights and light-weight decorations like garland or plastic ice cycles.
Any heavy objects, or large light-weight objects…inflatable Santa’s or plastic reindeer, for instance…should not be attached on or near your solar panels since they will block sunlight.
Most large decorations are put up in the fall and winter months when sunlight is already reduced, so don’t do anything that can jeopardize those precious rays of the sun from reaching your panels!
Can You Stack Solar Panels On Top Of Each Other?
Typically, you will want to avoid stacking solar panels as they can cause damage and blocks other photovoltaic cells. If storing your solar panels you will want to cover them with moving blankets or cardboard to prevent dust build-up and scratching.
If possible, you will want to store solar panels vertically rather than horizontally since this will prevent any weight stress on your panels. Remember to cover them with blankets, several layers of plastic, or cardboard to keep dust from building up and for extra protection.
Over the years engineering and manufacturing processes have improved and solar panels have become more durable.
Even though it’s not the greatest idea to walk across your solar panels, most brands can handle it as long as you’re careful.
While hanging Christmas lights and other lightweight decorations from the framing of your solar panels is perfectly safe and won’t affect solar efficiency, remember to avoid placing any items on your solar panels…whether they are heavy or not. Blocking out any sunlight will greatly reduce the energy output of your solar panels.
That about covers it for solar panel weight limits, but if you’re curious about if your roof can handle the weight of your new solar array, check out this article.