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Solar Panel Cleaning
Solar panel cleaning should be considered where ever solar panels are installed.
Lichens, moss and algae and other dirt and debris can begin to grow on solar panels if not cleaned regularly.
Solar panels should be cleaned regularly to ensure maximum efficiency and energy production. Here are some tips on how to clean solar panels:
Turn off the power: Before cleaning the solar panels, make sure to turn off the power to avoid any accidents.
Wait for the panels to cool down: Cleaning solar panels when they are hot can cause them to crack, so wait until they have cooled down before starting.
Use the right tools: Use a soft-bristled brush or a non-abrasive sponge to clean the panels. Avoid using abrasive materials such as steel wool, as they can scratch the surface of the panels.
Use pure water: Pure water will help to avoid leaving water marks on the panels. Avoid using high-pressure water, as it can damage the panels.
Use soap if necessary: If the panels are very dirty, you can use a mild soap solution to clean them. Make sure to rinse thoroughly with water afterwards to avoid suds and marks being left on the panels.
Be careful with the electrical components: Do not spray water directly onto the electrical components of the solar panels. Use a damp cloth to clean them instead.
Be safe: When cleaning solar panels, make sure to follow safety guidelines, especially when working at heights.
Hire a professional: If you’re not comfortable cleaning the solar panels yourself, consider hiring a professional solar panel cleaning service.
Remember, regularly cleaning your solar panels can help maintain their efficiency and prolong their lifespan.
Why Do Solar Panels Need Cleaning?
Solar panels are designed to convert sunlight into electricity, and they do this by absorbing light and converting it into energy. Over time, dust, dirt, leaves, bird droppings, and other debris can accumulate on the surface of the solar panels, reducing their ability to absorb sunlight.
When solar panels are dirty, less sunlight is absorbed, which means less energy is produced. This can lead to reduced energy output and lower efficiency, as well as reduced return on investment for the owner of the solar panel system. In addition, if debris is left on the panels for an extended period of time, it can cause permanent damage to the panels and reduce their overall lifespan.
By cleaning solar panels regularly, you can ensure that they are able to operate at maximum efficiency, which means you will get the most energy possible from your solar panel system. In addition, keeping your solar panels clean can help extend their lifespan and save you money in the long run by reducing the need for costly repairs or replacements.
Is Solar Panel Cleaning Worth It?
Whether or not solar panel cleaning is worth it depends on a variety of factors, including the location of the solar panels, the amount of dirt and debris that accumulates on them, and the cost of cleaning.
In general, solar panels do require some level of cleaning to maintain their efficiency and output. A study conducted by the National Renewable Energy Laboratory found that dirty solar panels can lose up to 25% of their energy output, which can result in significant financial losses over time. Therefore, regular cleaning of solar panels can help maintain their efficiency and prolong their lifespan, which can ultimately save money in the long run.
How often solar panels need to be cleaned varies depending on the location and environment. If the solar panels are located in an area with a lot of dust, debris, or pollen, they may need to be cleaned more frequently than panels located in a cleaner environment. In general, it’s recommended to clean solar panels at least once a year, but more frequent cleaning may be necessary in some cases.
The cost of cleaning a solar panel system also varies depending on the size of the system, the location, and the cleaning method used. Some companies charge per panel, while others charge a flat rate based on the size of the system. On average, the cost of cleaning a solar panel system can start from £25/ panel on residential properties but is highly dependent on access requirements.
On larger commercial jobs prices start from around £1000/ megawatt.
Professional Solar Panel Cleaning Services in London
Dirty solar panels cost you money. Dust, bird droppings, lichen and traffic film all block sunlight from reaching your photovoltaic cells. Studies show that heavily soiled panels can lose up to 25 per cent of their generating capacity. For a typical London home generating £500 to £700 worth of electricity a year, that is a significant loss from panels that simply need a clean.
Here at LBC we provide professional solar panel cleaning services for homes and businesses across London and the surrounding Home Counties. We use deionised water and water-fed poles, cleaning from ground level wherever possible. No ladders on your roof, no risk to your panels and no mineral residue left on the glass.
Our Solar Panel Cleaning Process
We do not just rinse your panels and leave. We follow a proper methodology that protects your investment and keeps your manufacturer warranty intact.
1. Initial Inspection
Before we touch anything, our team carries out a visual assessment from ground level. We check for visible damage, cracked cells, loose fixings, bird nesting under the array and the type of soiling present. You get a brief verbal report as part of every clean.
2. Safe System Isolation
We advise you on isolating your solar PV system before we begin, following the shutdown procedure recommended by your inverter manufacturer. This protects our team and your equipment.
3. Deionised Water Cleaning
We use purified, deionised water fed through extended soft-bristle poles. Deionised water has had all mineral content removed, which means it leaves no water marks or streaks when it dries. For the vast majority of London properties we can clean from the ground or a safe standing position. No access to your roof is needed in most cases.
4. Treatment for Stubborn Soiling
For bird droppings, lichen or heavy soiling that deionised water alone will not shift, we apply a specialist biodegradable cleaning solution. It is fully safe for PV glass coatings and manufacturer approved. We do not use abrasives or pressure washers on panel surfaces. Both can void your warranty and damage the anti-reflective coating.
5. Final Rinse and Check
After cleaning we carry out a final purified water rinse and then a second visual check to confirm even coverage. We flag any damage or issues we spotted during the clean so you know exactly what state your system is in.
Residential Solar Panel Cleaning
Most of our domestic customers have panels on a pitched roof. Our water-fed pole system is designed exactly for this kind of job. We regularly clean standard domestic arrays of 6 to 20 panels in a single visit, usually completed in 30 to 60 minutes with minimal disruption to your day.
We recommend annual or bi-annual cleans for London homes depending on your local environment. Properties near parks, trees, main roads or construction sites will benefit from more frequent cleaning. We can set up a maintenance schedule so you never have to think about it.
- Fully insured with comprehensive public liability cover
- No access to your roof required in most cases
- Weekday and weekend availability
- Visual inspection included with every visit
Commercial Solar Panel Cleaning
Commercial and industrial solar arrays represent a major capital investment and an important source of on-site renewable energy. The financial impact of soiling at scale is considerable. A 100kW rooftop array losing 10 per cent of its output is losing thousands of pounds of value every year.
We work with facilities managers, property companies, housing associations, schools and commercial landlords across London and the surrounding counties. We handle everything from flat-roof commercial systems to complex multi-building arrays. For larger jobs we carry out a free site survey to assess access, health and safety requirements and cleaning methodology before providing a detailed quote.
Why Choose LBC?
We have been cleaning London buildings since 2012, working for everyone from individual homeowners to councils, housing associations and major commercial clients. What makes us different is simple.
- We use proper equipment. Deionised water systems and solar-rated cleaning solutions, not garden hoses.
- We are fully insured. Comprehensive public liability cover protects your property on every visit.
- We work safely. Our team is trained to work at height using MEWPs, rope access and specialist access equipment when it is needed.
- We are honest about pricing. Every quote is free and fully itemised. You only proceed if you are happy.
- We care about results. We have built this company on word of mouth and repeat business. We want your panels to perform and we want you to come back.
Frequently Asked Questions
Q: How often should solar panels be cleaned in the UK?
We recommend a clean every 12 to 18 months for most London properties. If your panels are near trees, a busy road, farmland or the coast, twice a year is better. After a dry summer or a period of heavy bird activity it is always worth booking a clean regardless of schedule.
Q: How much does solar panel cleaning cost?
Our prices start from £75 for smaller domestic systems and typically range from £100 to £200 for a standard home installation. Larger commercial systems are quoted individually after a free site assessment. The final price depends on the number of panels, roof pitch and access requirements.
Q: Can I clean my solar panels myself?
You can, but we do not recommend it. Working at height on a roof carries significant safety risks. Using the wrong equipment, such as a pressure washer, tap water with high mineral content or abrasive cloths, can scratch the glass, leave mineral deposits or even void your manufacturer warranty. Our team uses deionised water and soft brushes from the ground wherever possible, so there is no risk to you or the panels.
Q: Do solar panels need cleaning in the rainy UK climate?
Yes, more often than people expect. Rain removes loose dust but it cannot shift bird droppings, tree sap, traffic film, pollen or lichen. These contaminants can reduce output by 5 to 25 per cent and, if left long enough, can permanently damage the anti-reflective coating on the glass.
Q: What happens if you do not clean your solar panels?
Uncleaned panels lose efficiency gradually. Dirt and soiling typically cause a 2 to 7 per cent annual efficiency loss in UK conditions, rising to 25 per cent in heavily soiled cases. Bird droppings are especially damaging. A single dropping on a cell can reduce that panel’s output by 20 to 30 per cent if you have a string inverter. Moss and lichen, if left for years, can cause physical damage to the panel surface.
Q: How do professional solar panel cleaners work?
We use a water-fed pole system with deionised, purified water. The pole extends from ground level so we rarely need to go onto the roof, which keeps the process safe and fast. The purified water leaves no mineral residue when it dries, so panels come up spotlessly clean. For stubborn soiling or commercial arrays we use specialist biodegradable cleaning solutions that are safe for PV glass coatings.
Q: Will cleaning my solar panels increase their output?
Yes, in most cases. A professional clean on a heavily soiled system regularly improves measured output by 10 to 20 per cent. For a typical 4kW domestic system generating £500 to £700 worth of electricity per year, even a 10 per cent efficiency gain means £50 to £70 extra in savings annually. That is often more than the cost of the clean itself.
Q: Is it worth paying for professional solar panel cleaning?
For most roof-mounted systems, yes. The cost of a professional clean is typically recovered within the year through improved electricity generation. Beyond output, a professional clean includes a visual inspection of your panels, so any damage, loose fixings or bird nesting issues are caught early before they become expensive repairs.
