There is supposed debate around the topic, “do solar panels need cleaning?” Some claim that rain is enough for the panels to remain spotless. Or, even if cleaned, it doesn’t make much of a difference in the efficiency rate. I’m here to tell you that, regardless of where you live, your solar panels do need cleaning. But what matters is how often you clean your solar panels; it will vary depending on where you live and the condition of the panels.
It is not personal speculation that solar panels require cleaning; rather, it’s backed by several studies and science that they indeed need to be cleaned.
Why Solar Panels Need Cleaning
To answer this question, let’s first explore how solar panels work.
Your typical solar panel that is found in millions of homes worldwide is made from silicon, the seventh most abundant material in the world.. For its amazing semi-conductorial properties make it the prime material for manufacturing solar panels.
When exposed to the sunlight, the solar panels actively convert it into DC (Direct Current) electricity. The more exposure to light, the more electricity you get. As simple as that. The angle of the sunlight matters, but that is an issue for a deeper discussion on the topic. Let us skip that for now. Solar panels need direct sunlight to generate more energy, and what comes in the way of it? You guessed it! Dirt, grime, bird poop, and so many other things which indeed need to be cleaned for your solar panels to work at their maximum capacity.
The Reason Behind Declined Efficiency Rate
Accumulation of dirt can result in your solar panels losing their efficiency pretty fast. Many reports suggest that you can lose about 25% of the expected energy; in worst cases, up to 30% of energy loss can occur if solar panels are not cleaned. (Source).
Losing 30% of expected efficiency is a huge loss. Your payback period can potentially be pushed back further away. It has been proven that cleaning the panels can jump back your conversion rate almost immediately.
How To Clean Solar Panels
You may second guess cleaning your solar panels because of the involved labour cost. But I am here to tell you that you can clean your solar panels on your own without even having to spend a single dollar. Here are the steps to clean your solar panel-
First and foremost, you have to water your solar panels. You need nothing but simple tap water for it. This way, all the dirt that could be stuck on the surface of the panels will soften. For example, bird feces or accumulated pollen are the ones that are most prone to getting stuck and drying on the surface.
Use Gentle Cleaning Agent
Now spray on or lay down some gentle cleaning agent like diluted dish soap or diluted vinegar onto the panels. You don’t need to use anything fancy or buy anything for this purpose only. Use what you have lying around the house. But refrain from using any harsh chemical or harsh cleaning detergent. That will leave behind permanent damage.
With a soft bristle brush, gently scrub down the surface of the panels. A piece of microfiber cloth will get the work done as well. The key here is to use gentle strokes and use a soft vessel for scrubbing.
Rinse down the panels after you are done scrubbing. Make sure there is no soap residue left on the surface; otherwise, it will leave behind the gunk and will attract more dirt.
Now that you are done cleaning squeegee down the panels to dry. Water spots are one of the primary reasons why your panels lose efficiency over time.
And that is it! That is how you clean solar panels
Waterless Solar Panel Cleaning
It’s not a myth that cleaning solar panels requires quite a lot of water, and this number accumulates to 20 gallons of water for per megawatt-hour. Your typical rooftop solar will not require so much water, but with that, you get an idea of it. Initially, cleaning solar panels by yourself is the cheapest way to increase the efficiency rate; however, it would be even cheaper if you did not need to use water.
Dry brushing is one of the techniques used to clean the rooftop PV, but I will definitely not recommend this method. It can damage your panels if not done correctly, so unless you are confident about dry brushing, I suggest you not to take that route.
There is another technology that is on the verge of being perfected and commercialized for solar panel cleaning. A team of excellent researchers at MIT are now working on this new piece of tech, which allows the panels to be cleaned without using water or brushes. This new device employs electrostatic repulsion to induce dust particles to separate and almost leap off the panel’s surface.
Read more about the new tech – Here.
Cleaning your solar panels is the single most efficient and economical way to dramatically increase your efficiency rate overnight. Also, cleaning the panels cools down your system, which contributes to increased electricity generation. So, to answer the question, do solar panels need cleaning, I would say yes, they do.