Solar panels are an increasingly popular form of renewable energy generation, used in both domestic and commercial settings. In terms of domestic usage alone, more than 1.2 million homes in the UK are equipped with solar panel installations. But how many solar panel owners understand how to properly clean and maintain them?
Renewable energy is here to stay, so you need to know how to keep your solar panels in top condition for the long haul. Throughout this blog, we will be exploring this topic in-depth in order to equip you with that all-important knowledge.
The benefits of regular solar panel cleaning
Before getting into the nitty-gritty of how to maintain your solar panels, let’s get into why it matters.
Increased efficiency
It’s not just about the aesthetics – cleaning your solar panels can actually boost their efficiency. Research has found that dirty solar panels can suffer a 25% reduction in energy output compared to those that are fully clean (source: The National Renewable Energy Laboratory)
It makes sense, right? Solar panels operate on the principle that the more light hits their surface, the more energy they are able to generate. Therefore, when the surface of a solar panel is covered in a film of dirt and grime, less sunlight is able to pierce through and be converted into energy. In fact, the loss of power caused by an unclean solar panel has a name: soiling loss.
It is worth noting that rain does not clean solar panels, much like rain does nothing to clean a car windshield. Manual cleaning is required to restore them to their optimum potential.
Cost savings
It goes without saying that the more efficient a solar panel is, the more value it provides for its owner. If you want to experience the full benefits of your solar panel, make sure it is completely clean so that it is operating at its maximum efficiency.
Additionally leaving a build-up of debris alone for too long can cause physical damage to the panel, which you naturally want to avoid. There are several different types of damage that can occur to your solar panel, including Potential Induced Degradation and Isolation / Insulation Resistance. If unchecked, the former can result in the complete deterioration of the panel, rendering it functionally useless.
Improved lifespan
Speaking of debris-inflicted damage, this can affect the lifespan of your solar panel. If too much damage is inflicted, the proper functioning of your solar panel can be affected, and eventually it can stop working completely. If this occurs, you will have to splash out on a brand new panel. However, proper cleaning can help you to avoid this worst-case scenario.
Positive environmental impact
As established, a fully clean and operational solar panel is more efficient, and is therefore able to produce greater amounts of renewable energy than one that is dirty. Therefore, clean solar panels have a more positive environmental impact due to their ability to effectively produce green, sustainable energy.
Factors affecting solar panel performance
So, what does “dirty” actually mean in the context of a solar panel? There are a variety of different elements that can buildup and negatively affect their performance.
Dust, dirt, and debris
The most common cause of dirty solar panels is a buildup of dust, dirt, and debris. This occurs naturally over time – in part due to their tilted, upwards-facing angle that exposes them to natural elements. Of course, this accumulation of debris blocks sunlight and makes them less efficient, but it also damages their aesthetic qualities. Let their reflective surface shine!
Weather conditions
It is a common misconception that rainfall cleans solar panels. You can understand the thinking that rainwater washes away any dirt that plagues the solar panel’s surface, but this is simply not true. Consider your car windshield – rain may rinse away the surface level of dust and dirt, but you cannot rely on it to wash away the grime that is baked in, and the same goes for solar panels.
In fact, rain can actually wash some dirt to the edges and corners of your solar panel, actively worsening its overall efficiency as it heats up.
On the topic of heat, the most damaging weather condition that can affect your solar panels is that of extreme heat. Most solar panels function at peak efficiency between 15-35°C, but will start to become less efficient at highs of 65°C. It is fortunately unheard of for UK temperatures to reach such extremes, so your solar panels should be safe if exposed to normal outdoor temperatures.
How often should you clean your solar panels?
So, we have established the importance of cleaning your solar panels. But how often should you actually make the effort to manually clean your panels?
General guidelines
The frequency with which a solar panel should be cleaned depends on a variety of factors, such as location and the rate at which dirt, dust, and debris builds up.
However, it is typically understood that solar panels should be cleaned every 6-12 months (or once to twice a year) in order for them to consistently operate at their optimal capacity.
You may have heard that solar panels in the UK are self-cleaning. While it is true that they possess a hydrophobic coating to repel water (and the dirt within them), manual cleaning is still required to keep your panels functioning at their optimal performance.
Factors that may affect cleaning frequency
Depending on certain factors, you might need to clean your solar panels more often. One such factor is location. If the air surrounding your solar panels contains more dust, pollen, or other debris, you may need to clean them more frequently than an area with cleaner air.
On the other hand, if you live in an area that experiences frequent and heavy rainfall, you may need to clean them less often.
You can check the status of your solar panels manually and make your own judgement as to whether they require cleaning. Keep in mind not to leave it longer than a year.
Tips for cleaning your solar panel yourself
Enlisting the services of a professional cleaner may not be an expense you want to make, but it is possible to clean your solar panels manually. Before you get started, you’ll need to know what equipment to acquire.
Recommended tools & supplies
The easiest way to get your hands on all the right equipment is to purchase a dedicated solar panel cleaning kit.
These typically include a specialised extendable brush with in-built water jets. They should connect to a typical garden hose, enabling you to safely and easily clean your solar panels from a distance.
If you don’t want to shell out on a specialised brush (which can cost upwards of £100), you can adopt a more basic approach. Obtain a soft-bristled brush (which will not damage the panels) and a garden hose. In order to safely reach your solar panels, you will want to invest in a brush with a long or extendable handle (hose compatibility is handy but not essential, and makes this process a much greater investment).
When it comes to the cleaning solution, you’re always best taking the advice of your solar panel manufacturer. However, if they have not recommended a specific brand or mixture, you can always rely on a basic soap and warm water solution to get the job done. For easy application, also remember to obtain a spray bottle with which to apply the solution.
Step-by-step cleaning process
Now you’ve got your equipment, it’s time to clean. This step-by-step guide is all you need to clean your solar panel manually.
- Switch off your solar panel
Before you do anything, you need to turn off your solar panel system. Despite your solar panel’s waterproofing, it is better to be safe than sorry, and by cutting power to the system, you will prevent it from being damaged in an unfortunate accident.
- Spray the surface
Using a spray bottle, apply the solution to the surface of your solar panel. If the grime is particularly baked in, let the solution sit for several minutes before moving onto the next step.
- Wipe the surface
Gently scrub the surface of the solar panel using your soft-bristled brush. Apply just enough pressure to clean the solar panel, but not too much as to damage it. The solution should have done most of the cleaning work, so intense scrubbing is not necessary.
- Rinse the surface
With the solar panel wiped clean, you’ll just need one last rinse with a garden hose to fully wash away any excess debris or soap. Choose a gentle setting – the surface needs a rinse, not a jet wash – to avoid unnecessary damage.
- Wipe the panel dry
Wait for your brush to dry off, or use a separate dry cloth to dry the surface of your solar panel. Wipe away any water and streak marks to ensure your solar panel is spotless and glossy! It would be an ironic shame to get this far and leave marks or streaks that make your solar panel less efficient.
With that, your solar panels should look as good as new! In the event that they still have marks, feel free to repeat the process until they look immaculate. Once you’re happy, restore power to the system and enjoy the benefits of a fully clean and efficient solar panel.
Safety precautions
When cleaning your solar panel, it is important not to inflict any unwanted damage to the system during the process. There are several safety precautions to consider in order to safely clean your solar panels without error.
First of all, as mentioned, you should cut any power to the system before cleaning to prevent any electrical damage from occurring. It is also possible to damage the system by using harsh chemicals. You may assume a harsher cleaning solution will be more effective at removing dirt and debris, but it can actually inflict severe damage to the system. Therefore, stick to using a gentle cleaning solution instead.
Alongside the solar panel, you’ll also want to protect yourself.
Solar panels are typically placed on roofs, and can therefore be risky to access. How you clean your panels is up to you – in this guide, we recommend using an extended brush to safely clean them from a distance – but if you choose to position yourself on a roof, consider wearing a safety harness. Additionally, consider cleaning during daylight hours to improve visibility and prevent accidents.
Professional solar panel cleaning services
As our five-step process suggests, cleaning your own solar panels is absolutely a possibility. However, it is not a solution for everyone. Some solar panel owners may prefer to hire the services of a professional solar panel cleaner, or they may not have a choice.
Why hire a professional?
Most solar panels are installed at moderate heights to maximise their access to sunlight. However, this can make them less accessible to their owners when it comes to cleaning them.
In cases where you do not wish to, or are unable to reach your solar panels, you may wish to enlist the services of a professional. Naturally, they are trained and equipped to work effectively at heights, so you can rely on them to make the inaccessible accessible.
In rare cases, your solar panel may be experiencing a particularly high level of debris buildup that is extra difficult to clean manually. It can be tricky to exert enough pressure to clean baked-in grime without damaging the system, which is where the services of a professional can come in handy. Don’t risk breaking your costly solar panel system, as repairs or replacements will set you back more than hiring the services of a professional cleaner.
Lastly, you can’t underestimate convenience. Even if you are fully equipped to clean your solar panels manually, you just might not have the time or energy. Why not rely on professional cleaners to do the job quickly and thoroughly while you get on with your day-to-day activities.
Cost considerations
While it may be more convenient to hire professional solar panel cleaning services, we understand there are cost implications that may deter you from choosing this option.
In the UK, solar panel cleaning can range between £4 – £15 per panel, depending on a variety of factors. Solar panels that are larger, harder to reach, or significantly dirtier will likely cost more to clean. However, the exact price will depend on your specific situation and the company you select.
When considering the option of manual vs. professional solar panel cleaning, there is no one-size-fits-all solution. The answer is dependent on each individual’s unique situation. Keep these factors in mind and evaluate your options carefully.
Conclusion
When it comes to cleaning your solar panels, there are plenty of options available to you. Depending on your situation, you may choose to clean them yourself or opt for a professional cleaning service.
Whatever you may choose, it is important to get your solar panels cleaned regularly (ideally, every 6-12 months) to maintain their efficiency and enhance their life expectancy.
BGreenn is all about bringing green energy to as many people as possible. Our team is committed to making this process as quick, simple, and accessible as we can. If you have any questions about solar panel maintenance or require installation support, get in touch with us on 03330 090 848 or by emailing [email protected].