Does Rain Help Or Hurt How Much
In a study conducted in Spain, researchers measured an average performance reduction of only 4.4 percent after a years worth of dust buildup. Most solar panel owners could probably live with that. But the study also found that in long periods without rain, daily energy losses can be higher than 20%.1 So, in a dry climate where dust buildup is the main issue, the problem remains pretty simple: a lack of rain results in dust buildup that might get progressively worse the longer the dry spell lasts.
Meanwhile, normal rainfall can rinse away dust and keep solar panels producing at around 95 percent of their maximum capacity. That conclusion might lead you to assume that solar panels in climates with frequent rainfall should require less maintenance. Not so fast! Most of the time theres more to the equation than just dust. Pollen, bird droppings, leaves, ash, and a hazy film that can form when smog or smoke hang heavy in the atmosphere can all combine into a layer of surface soiling, which may or may not wash away in the rain. Heres a report from Renewable and Sustainable Energy Reviews2 that digs into the many complex variables involved. The research concludes that allowing rain to do the work of cleaning solar panels is a fine decision if, and only if, you live in the right kind of place, such as:
Different Ways To Clean Solar Panels
The only way to keep your solar panels operating at maximum efficiency is to clean them periodically. However, solar panels are not windows, and while they need cleaning, you cannot just spray window cleaner and use paper towels. Solar panels require special care.
Your solar panels location is also an important consideration, especially for your safety and to prevent breaking or damage to the panels. Many things can damage your solar panels, however minutely.
When choosing your supplies, keep in mind that many detergents and powders are harsh, will scratch the surface, and possibly endanger the environment.
Soap and detergents are also prone to streaking, ultimately leaving behind a residue that will essentially have the same effect as shading on your systems performance .
Q: How Often Should Solar Panels Be Cleaned
Unfortunately, it is often the case that the installation date the last time a solar system owner ever looks at their panels until something goes wrong.
We at Lime Solar Cleaning recommend that panels be cleaned and inspected at a minimum once every six months. Cleaning at regular intervals prevents buildup of residue and keeps your panels operating optimally at all times.
Regular checks can also prevent cracks or fire risks from developing into something worse but youll need to know what youre looking for in order to identify these issues in the first place.
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How Much Does It Cost To Clean Solar Panels
The price to clean a Solar Panel Array depends on the size of the PV System and the ability to access your roof. If scaffolding is required to safely reach your Solar Panels, the price is most likely to be more costly. A professional Solar Panel Clean is usually charged per panel. Here at Deege Solar we charge £500 for a full Solar Panel Clean and we operate at that price Nationwide. To find out more about our Solar Panel Cleaning Services, simply click here.
Here at Deege Solar, Solar Panel Cleaning forms part of our monthly Maintenance Packages. For just £27.50 a month, you can receive a yearly solar panel clean and system health check by our Solar experts. On top of that, you will receive free repairs On all Accidental Damage and full technical support all year round.
Is Cleaning Your Solar Panels Necessary
Its vital that regular maintenance is carried out on your solar system this includes cleaning.
Regular maintenance will ensure that your panels are operating correctly, safely, and efficiently.
Dust, debris, vermin, bird poop, hail, snow, water stains all of these are elements that your panels will have to deal with. Each of them can damage your PV system.
The following scientific experiments demonstrate the effect that dust can have on solar panel efficiency:
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What You Should Know About Solar Panels Cleaning
Do solar panels require regular cleaning or maintenance?
This is a commonly asked question. And luckily, the answer is no. Nature does the most of the work for you by keeping your solar panels clean and free of debris with just a little rain. However, a little maintenance and cleaning once or twice a year can help improve the production capacity of your solar systems. This article will teach you how to clean the solar panels and when you should seek professional assistance.
Does Rain Help Clean Your Solar Panels
Years ago, many people, including some panel manufacturers would happily tell you, dont use anything but rainwater. Sadly, many solar panel owners took that information and ran with it.
While rainwater does have the ability to somewhat rinse your solar panels it is not capable of doing a good enough job on its own.
Not entirely convinced? Lets use an analogy involving a car.
If a car is dirty and has been standing outside for some time, what do you suppose it would look like after a rainfall? The answer not that much better.
Why? Because even though some of the dirt has been washed away, the majority of it will have just shifted to different areas of the car.
All of that dirt will accumulate and turn into muddy streaks that run down and stick to the outside of your car. The exact same thing happens to solar panels.
During rainfall, the dust and dirt begin to shift further down your solar panels, causing streaks. Even worse, it accumulates at the bottom of the solar panels, obstructing the lower cell row and hindering the production efficiency.
Sure, very heavy rain may help a little bit more, but it is not a substitute for mechanical solar panel cleaning.
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Frameless Panels Stay Cleaner At Low Angles
If you cant avoid installing panels at an angle under a 10 degrees, frameless panels can help. These have no metal frame around the edge and are often called glass-on-glass or double glass panels because the solar cells are the filling in a glass sandwich. The lack of frame helps water flow off them and keep them clean.
Is It Necessary To Clean Solar Panels
Hey Mr. Green,
I generate about 140 to 160 percent of my annual electricity consumption while putting excess power back on the grid. But I have never bothered using software to track my solar panel performance. How much better do solar panels perform if they’re washed each year?
Michael in Santa Clara, California
University of San Diego researchers looked into this question and concluded that since less than 0.05 percent of energy could be lost per day due to dirt, it was not worth the effort or the expense to clean solar panels. Even a mild rain rinses off most of the obstructing dirt, pollen, etc., which led them to conclude that hiring someone to clean the panels does not pay off.
There are, however, a few exceptions that can make cleaning the panels worthwhile. If your panels are installed at less than a 5 degree angle, then they should be washed periodically because rain alone might not carry away the accumulated dirt.
Engineers also found a few sites where photovoltaic panels were dirty enough to warrant cleaning due to specific, localized circumstances. For example, being directly next to and downwind of a highway, factory, or agricultural field may generate enough dirt to warrant periodic cleaning.
A third issue is bird droppings, which, if heavy enough, could block enough sunlight to make a cleaning necessary.
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Important Tips For Cleaning Your Solar Panels
So, youve assessed your solar panels and concluded that they need to be cleaned. If you feel confident enough to do it yourself, here are some important tips to consider before you begin cleaning your panels. And remember, safety always needs to be your top priority!
Always follow the maintenance instructions provided by your installer. If in doubt, check with the installation company.
Avoid cleaning solar panels during the hottest part of the day. Not only is this a hazard to your health, but the extreme temperature variance may cause the glass to crack too. Many commercial cleaning products are too harsh to use on solar panels, so its best to avoid them. Mild soap and clean water, a hose, a soft sponge, and a squeegee are all you need to do the job yourself.
The use of pressure washers and hard-bristle brushes is not advisable. As a precautionary measure, shut down the system before cleaning the panels.
Q: What Are The Benefits Of Having Your Solar Panels Cleaned By A Professional As Opposed To Cleaning Them Yourself
Tap water and chemicals can leave a residue on your panels that can inadvertently encourage dirt to accumulate. This is one of the reasons that having your panels cleaned professionally is a good idea. Using a de-ionised water system to give an effectively spot free finish that is more resistant to becoming dirty will also give you a better result with a longer-lasting impact. De-ionised water systems are not generally worth the investment for individual homeowners who plan to use them only for window cleaning, but a good professional cleaner will have one as a matter of course.
Another part of having a trained professional do the job is that they can check other aspects that can affect the health and performance of your system. These include potential fire safety issues, cracks, hot spots and nests from uninvited guests like birds, rats and possums. Detecting issues like crazing and delamination are also essential to to ensure a system running well.
Another reason to go professional is safety: Getting on your roof can be a dangerous business, especially without good safety gear. Without the right gear and experience, you could put yourself at risk or potentially injure yourself .
A wasp nest underneath a solar panel.
Find out more about Solar Panel Cleaning and Costs:
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Determine What Is Making Your Pv Panels Dirty
Sometimes, it is merely dust that obscures your solar output. Dust is more likely to accumulate on solar panels in dry climates. For example, if tall deciduous trees surround your home, you might get leaves covering your panels, especially in the fall. Likewise, bird droppings are more common if you have trees nearby. Unfortunately, in some places in Oregon, it can be humid enough for moss to grow on solar panels, and this cant merely be removed by rinsing with a garden hose. Also, ash can accumulate if there are a lot of wildfires in your area.
Typically, we get plenty of rain in the Willamette Valley to keep solar panels clean and working well. However, if you live in a dry part of Oregon with little rain, it might be worth rinsing the dust on your solar panels with a hose on rare occasion. This is an especially appealing option if you can hose off your panels while standing on the ground, and it doesnt require a ladder.
Also, the flatter your solar panels are mounted, the more contaminants and even leaves can accumulate. If your panels are nearly flush on a flat roof, cleaning them will be more critical. However, if your panels are mounted on a steeply pitched roof, dust, pollen, ash, leaves, and other contaminants can easily slide off.
Tips For Cleaning Solar Panels
If you determine that your solar panels have more than just dust, you might be considering cleaning them. Some roofs, such as flat roofs, can be safely and easily accessed without using a ladder. Whether it is worth cleaning your PV modules depends a bit on how difficult it is to access them. It is OK to leave a bit of dirt on the panels and have slightly lower electricity output. If you decide to take action, you can clean them using a mild soap and a cleaner.
As always, safety first. It is critical to ensure that you can safely clean your panels. Depending on the layout of your home, this might be difficult. If so, just forgo cleaning them or hire a professional. Keep in mind that our solar panel installers are highly trained in roof safety and use harnesses. For some roof types, you might not be able to clean your panels effectively without safety gear and knowledge. Also, review the ladder safety tips above before getting started.
If you move forward with cleaning your panels, use a mild detergent and a soft brush, scrubber, sponge, or squeegee. Make sure that you dont use anything that will scratch or damage your panels. This will create a long-term decrease in solar energy output so it is definitely something to be avoided.
First, wet the solar panels using a hose or low-pressure sprayer. Next, gently clean the panels with a sponge, rag, or squeegee. Finally, rinse your PV panels and allow them to air dry. You do not need to towel dry the panels.
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Even Washing Your Panels Once A Year Can Improve Efficiency
Beyond basic debris removing, it is recommended by most solar experts that you give your panels a thorough cleaning at least once a year. An annual clean up has been found to improve energy output by as much as 12% when compared to panels that were only cleaned by rainfall. If you have time to bump it up to twice a year, even better!
There are a lot of products and cleaning solutions available that are formulated for use on solar panels. There are even solar panel cleaning robots – but most find that mild soap and a soft, glass friendly cloth do the trick just fine.
Youll want to do your cleaning early in the morning or in the evening. When the sun is out in full force, solar panels can heat up quickly and make the washing experience more difficult. This is especially true in the summer months.
If youre working with roof-mounted panels, be sure that youre going about it safely! If youre working with hard to reach spots, try attaching the cloth that youre using to an extendable brush so that you arent putting yourself at risk of falling.
Have any questions about solar panel maintenance?
Q: How Much More Productive Are Solar Panels When They Are Clean
In the past, it was generally accepted that the rain would clean the panels. More recently, this conventional wisdom has come into question with new discussion and articles on the subject.
This is an interesting article on the analysis of dust losses in photovoltaic modules. It was conducted for the World Renewable Energy Congress in Sweden. It highlights that dust buildup does have a significant effect on solar energy production contrary to popular thinking on the matter.
A good analogy is with your car windscreen: If you leave you car sitting outdoors for a few weeks, the buildup on this glass would make it difficult to see through without cleaning it. Even if it has cleaned, you would still need to clean it with the wipers or other means and even then, with more driving it will get too dirty to see through again.
Likewise, having dust, grime or buildup on your panels can reduce your systems energy yields by up to 25% and associated reductions in energy bill savings
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Consider How Often To Clean Your Solar Panels
Panel maintenance is important, but you probably dont have to clean your solar panels as often as you think. There may be the occasional bird droppings or collection of wind-swept leaves that need to be cleared away, so they get direct exposure from the sunlight, but generally speaking, panels stay clean enough on their own.
Your solar panels will naturally collect a little bit of dust throughout the day but thats not enough to stop them from absorbing sunlight and converting it into solar power. In fact, one study from the University of California San Diego observed thatwhen left untouched on a roof for 145 dayssolar panels only lost about 7.4 percent of their energy production efficiency.
When you think of all the heat, dust, and debris to which solar panels are exposed, its a little surprising that they remain so efficient, but theyre made to resist the elements, and we account for the dirt and debris when we design your solar energy system.
So yes, its probably a good idea to clean your panels every once in a while, but you dont have to do it nearly as often as most people think. If youre interested and dont feel much like dealing with the work of cleaning the panels yourself , you may want to think about hiring out the work. A professional cleaner may be in a better position to clean your solar panels for you.
Cleaning Solar Cells Yourself Vs Leasing A Professional
While cleaning panels yourself may appear to be a big plus, in most situations, its a risk not only to your solar system and the panels warranties but also to your safety. Remember that no amount of power savings is worth that. You are also unintentionally causing damage to your system that far outweighs any benefits you might gain from cleaning the dirt off.
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