How to clean solar panels? Cleaning solar panels is essential for maximum energy yield. Dirt, such as dust, bird droppings and algae, can reduce the efficiency of your panels by as much as 25% Reduce. But how solar panel cleaning in a safe and effective way? As expert in solar panel cleaning, we share at Solarco five crucial tips to keep your panels optimally clean.
At Solarco we clean solar panels professionally with deionized water, as this is the safest and most efficient method. In this article, we explain how to clean solar panels best happens, why cleaning solar panels with deionized water preferred and why you Cleaning solar panels with Dreft or rainwater better to avoid.

Tip 1. Always use osmosis water - never clean solar panels with rainwater!
Many people think rain cleans, but cleaning solar panels with rainwater actually leads to streaking, scaling and lower yields. This is because rainwater contains minerals, dust, sand particles and often airborne pollutants (such as acid rain). When this dries up on the glass of your panels, it creates white chalk streaks and a sticky layer that attracts dirt - exactly the opposite of what you want to achieve.
Why cleaning solar panels with rainwater is not a good idea
- Lime and mineral residue: Rainwater contains calcium and magnesium that remain as white deposits when evaporated.
- Increased dirt holding capacity: The residue of dried rainwater forms a sticky layer that retains new dust and bird droppings faster.
- Reduced efficiency: Research shows that scale and stains can reduce energy output by 10-20%.
- No inspection or maintenance: Self-cleaning with rainwater offers no way to detect damage or micro-cracks early.
Advantages of osmosis water in solar panel cleaning
Osmosis water is completely free of minerals, lime and chemical contaminants. As a result, it offers streak-free, safe cleaning that does not affect the glass surface of your solar panels.
Advantages of osmosis water | Disadvantages of rainwater |
---|---|
No lime streaks | Leaves white deposits |
No chemical residues | Promotes dirt accumulation |
Environmentally friendly | Increases maintenance frequency |
Safe for glass | Can damage glass by minerals |
At Solarco, we combine osmosis water with soft, anti-scratch brushes and professional telescopic equipment. Thus we guarantee thorough, streak-free cleaning - without the disadvantages of cleaning solar panels with rainwater. Read on for the best tips on how to clean solar panels.
Tip 2. Never use Dreft or other detergents when cleaning solar panels
Although many homeowners think Cleaning solar panels with Dreft is a quick and cheap solution, in reality it is a recipe for trouble. Dreft and similar detergents contain oils and aggressive chemicals that leave a thin, greasy film on the glass surface. This film attracts new dirt, causing your panels to re-contaminate faster - and the efficiency drops by an average 10-20%
Why cleaning solar panels with Dreft is a bad idea
Problem | Explanation |
---|---|
Greasy layer | Soap residue adheres to the glass, trapping dust and bird droppings |
Damage coating | Chemical components attack the protective layer of solar panels, causing micro-cracks and loss of light transmission |
Warranty risk | Use of Dreft can void manufacturer's warranty with many manufacturers |
"Cleaning solar panels with Dreft and other cleaning agents can reduce long-term energy yield." - Expert at Solarco
Comparison: Dreft versus osmosis water
Method | Result | Impact on returns | Recommended? |
---|---|---|---|
Dreft / detergent | Leaves stains and film | -10-20% returns | โ |
Osmosis water | Streak-free, limescale-free & safe | +10-20% yield | โ |
Best practice for solar panel cleaning
Use only osmosis or demineralised water in combination with soft, anti-scratch brushes. This prevents residues, protects the coating and maximises your yield - with no risk to warranty or performance. Read on for the best tips on how to clean solar panels.
Tip 3. Cleaning Solar Panels with Rainwater? Not Effective!
A frequently asked question is: Can solar panels clean themselves with rainwater? The answer is no. Although rain sometimes washes away loose dust, it is insufficient to remove stubborn dirt, bird droppings and algae.
Why cleaning solar panels with rainwater is not a good idea:
- Rainwater contains pollution and limescale, which can cause streaking and staining.
- Bird droppings and mud are not washed away.
- In dry periods dust and sand sticking, reducing returns.
Rainwater alone is thus insufficient. For a truly clean installation, it is better to choose deionized water cleaning by an expert. Check out our professional cleaning options or read on for the best tips on how to clean solar panels.
Tip 4. Use the Right Cleaning Equipment and Work Safely
If you want to clean your solar panels yourself, it is important to work safely and with the right equipment. Improper cleaning can not only damage your solar panels, but also be dangerous when working on a roof.
What NOT to do:
- No pressure washer! This can damage the seals and push water under the panels.
- No hard brushes or scouring sponges! These can scratch the glass and coating.
- No soap or chemicals! This can leave streaks and reduce light transmission.
What you WILL be able to do:
- Use a soft brush with a telescopic handle.
- Work with deionized water for streak-free cleaning.
- Work safely: use a safety belt Or let a professional do the work.
No idea how to clean solar panels or have no experience with roof work or doubt about the right method? Then have your solar panels cleaned by Solarcoto make sure it is done safely and correctly or read on for the best tips on how to clean solar panels.
Tip 5. Have your solar panels professionally cleaned on a regular basis
To make your solar panels as efficiently as possible to make it work, is annual professional maintenance recommended. At Solarco we offer periodic cleaning services for both individuals as well as companies.
Why choose professional cleaning by Solarco?
- Specialist deionized cleaning without streaking or damage.
- Experienced and certified professionals with safe practices.
- Fixed rates and transparent quotations with no hidden costs.
- Protection of your investment and maximum efficiency.
View our solar panel cleaning prices and ask for a free quote to.
Cost of solar panel cleaning versus cleaning yourself
Method | Cost per cleaning | Advantages & disadvantages | Source |
---|---|---|---|
Cleaning yourself | โฌ10-โฌ50 (sponge + lukewarm water) | โ Low cost โ Risk of scratches, no inspection, little effect for stubborn dirt consumerbond.co.uk | Consumer Association |
Professional cleaning | โฌ125 for 1-25 panels (Solarco) | โ Safe, streak-free result โ Inspection & reporting โ Higher yield (+10-20%) milieucentraal.co.uk | Milieu Centraal |
Cleaning yourself with water and soft sponge is only effective for light soiling and carries warranty and safety risks. Professional cleaning delivers structurally more efficiency and prevents expensive repairs.
How to clean solar panels, the best service?
Don't just choose on price, but pay attention to quality, safety and transparency. Use this checklist:
Criterion | What to look out for | Source |
---|---|---|
Certification & insurance | VCA/ISO certificate + liability insurance | RFO maintenance tip rvo.co.uk |
Cleaning method | Osmosis water without chemicals | Consumer Association consumerbond.co.uk |
Transparent tariffs | Fixed price for 1-25 panels + per-panel surcharge | - |
Customer reviews & references | 4+ stars on Google or Trustpilot | - |
Inclusive inspection | Checking for micro-cracks & inverter status | Milieu Centraal milieucentraal.co.uk |
Conclusion: How to Clean Solar Panels in the Best Way?
Cleaning solar panels is essential to maximum energy yield guarantee. However, not all methods are suitable. Here are the main points To remember about how to clean solar panels:
โ
Usage deionized water for a safe, streak-free cleaning.
โ Usage no Dreft or other cleaning agents - this leaves a film behind.
โ Rainwater is not enough To keep solar panels clean.
โ
Usage the right equipment and work safe.
โ
Get your solar panels regular professional cleaning by Solarco.
No idea about how to clean solar panels? Want to be sure of a perfect cleaning without risks? Then choose a professional osmosis cleaning by the experts of Solarco.
๐ Apply now for a non-binding quotation via our contact page.
๐ Or call directly: +32 468 18 56 40We make sure your solar panels like new again perform!