So your photovoltaic system is dirty and you are asking yourself how to clean solar panels without damaging them or getting yourself electrocuted. Chances are that if you are reading this you probably think that your solar system doesn’t sparkle and shine as it did a year ago when you first installed it? Or maybe your electrical production has dropped some and you want to see if a good solar panel cleaning will fix the problem?
Who needs too clean their panels
The good news is that cleaning will not be needed very often and in fact most of the time not at all. This is because your roof has a natural slope to get rid of excess water and debris landing on it. Since solar panels often are placed on the roof of your home they will have the same slope. This means that most of the trash that would have gathered on top of your solar panels will simply roll off them. Other than that the forces of nature like rain and wind will keep your panels nice and self cleaning. The wind will blow away the leaves twigs and bugs accumulating on the panels and the rain will wash the panels clean of dust and dirt.
It is when it not rains that a sloping solar panel could need some help with the cleaning. Still even in extreme draughts where it doesn’t rain for 6 months it still won’t justify itself to hire a solar panel cleaning company. The price you will pay for the professional cleaning won’t come back to you in the form of heightened electricity production. If you do the cleaning your self on the other hand, the 20$ you earn in extra electricity output during that season may be worth the truble.
100% horizontal or flat laid panels on the other hand, are a totally different story. If you do not clean those here you can loose over 40% of your power making performance over a few years
Also if you live close by the sea your panels will need to bee cleaned a little more frequently because of the salt in the sea air. This salt will be baked stuck onto the solar panels if not washed away by frequent rains.
How to clean your solar panels
Cleaning ones solar panels is not hard at all. Simply put, if you can clean a window you can clean a solar panel. They may look scary and technical but in fact the technology is securely sealed inside the solar panel. All the electrical stuff is safely protected with aluminum frames, hardened glass and insulation. Making a solar panel very much alike a simple window and therefore it can be cleaned just like a window. Here are a couple of technigues:
Solar panel cleaning with the water hose technique
Just pull out your garden house and shower the panels once in a while. This will remove the majority of loose particles and sand that have accumulated on the solar panels. This technique is especially effective with non sloping panels since these are in need of some water pressure to get that dirt off of them. Because flat laid sun modules accumulate a lot of dirt and debris built up on them, the trick is how to clean the solar panels without allowing the dirt to scratch their precious surface. I find that a water house does this remarkably well. There are simple mouthpieces to buy that can be attached to the water hose to make the water squirt really high up. 12 to 15 meters squirting hight is not uncommon. This way roof panels can be easily cleaned from the ground. Take care not to squirt panels with these special high pressure mouthpieces to close up though. A too high pressure hitting the panels could result in impact damage and could push water in between the glass and frame.
How to clean solar panels with water and a soft broom
A soft household broom is great to use to gently scrub away persistent bird droppings from the solar panels. There are special washing brooms to buy with telescopic handles. These are fantastic since they make it easy to reach the panels from the ground. Make sure though the panels surface is free from loose dirt before you begin scrubbing, this is so that small pebbles and the like wont get caught under the broom and scratching the surface.
Washing pads, sponges, squeegees, bristle brushes
Basically anything you can use to clean your dishes or windows you can use to clean your solar panels. It is more or less a question in what’s preferable and practical to you. 3M dish washing pads, sponges, squeegees and bristle brushes anything goes, just don’t scratch the panels.
Soaps and Detergents
You can use plain water when cleaning your solar panels with pristine results. But for insistent stains like bird droppings you could use some soap with a clear conscience.
Today our soaps are biodegradable. Meaning that if let out into nature they will be completely broken down within 5 days. Detergents on the other hand are not, so be careful using those.
If you live in the city, the soapy water running off your solar panels will probably end up in the communal sewage system where it will be transported into cleaning facilities. Just like the water from your sink or toilet will. Even if the soapy water would run down into your lawn it won’t hurt it. The soap will be filtered through the layers of dirt, becoming totally decomposed before it gets very far.
On the other hand if your house is situated very close by a river or a creek you should be careful with using soap. Detergents can be hazardous to the aquatic life if let out in large enough quantities. If you feel like soap is necessary use as little as possible. But you should know that washing your solar panels with plain water will be sufficient 99% of the time.
Deionized water do I need it?
To avoid getting limescale buildup on your solar system you could rinse the panels with deionized water when you are done washing them. This water is free from salts and calcium that otherwise leave little ugly white spots on your panels when dried. These spots are not dangerous and will only remain there until next time it rains. These are the same spots that form on your car if you wash it by hand at home. Deionized water can be bought cheaply in big jugs and you only need a small amount just to quickly rinse your panels off. If softened water is hardly obtained, you can use ordinary rainwater to the same effect.
Can I get shocked when cleaning solar panels?
We all know that electricity and water doesn’t mix very well so questioning if it will be safe to spray electricity creating panel with your garden hose is a valid one. And that is specially the case since it is a fact that power production from a solar panel technically can’t be turned off. They will produce electricity for as long as there is sunlight.
But the simple answer is: No you won’t get shocked when doing a solar panel cleaning. Because you did hire a professional that did install your solar panels the right way didn’t you? And the panels you bought are at least standard panels with certifications and a guarantee to last for many years to come aren’t they? And your electrician used good isolated wiring when connecting your solar system together? Of course he did since he’s an electrician. And your solar panels don’t contain any cracks either because with the accompanying warranty you would already have all such problems fixed right? A correctly installed solar panel can get sprayed with water everywhere without any effect at all. Meaning you can merrily shower the front side, back side, the conduit, the wiring or any of the junction boxes, without any risk of electric shock.
So to conclude this shocking rant you should be fine washing your panels as long as your solar system doesn’t consist of a DIY kit of solar cells from eBay that you soldered together yourself. And as long as you didn’t put up those homemade solar panels in your spare time using clothes hanger and barbwire to make it work.