FACT: Solar Panel Cleaning Does NOT Require Brushing

There are plenty of misconceptions regarding solar panel cleaning. These range from “I don’t need to clean my solar panels because my installer told me they are maintenance-free” (we debunked this myth here) to “the only way to effectively clean solar panels is with a brush”. The truth is proper solar panel maintenance does NOT require “agitation”. When proactively cleaned multiple times each week, dirt and debris will never congeal on the surface of solar panels. The key to keeping your solar array blue and maximizing energy production is installing an automated cleaning solution, RST NightWash™.

Note: “Agitation”, refers to techniques that involve physically dislodging or removing debris or dirt from the surface of the panels. 

Solar panel soiling and cementation: A quick review

“Solar panel soiling” refers to the accumulation of dust, leaves, bird droppings, and other forms of debris that reduce a module’s ability to generate electricity and negatively impact the financial returns of both residential and commercial solar projects. 

When ignored, soiling often causes a phenomenon called “cementation”. Cementation occurs when the substances on the surface of a solar panel congeal and harden over time, making them stubborn and challenging to remove. This happens when the soiling materials accumulate and undergo a drying process; the combined effect of heat, sunlight, and moisture can cause these substances to stick together, forming a hardened layer that adheres tightly to the solar panel surface. 

Think about how much easier it is to clean a dirty dish immediately after cooking compared to the morning after the tomato sauce has already crusted onto the pan. As a result, routine cleaning efforts become significantly more difficult and time-consuming – for solar panels, this potentially reduces their overall effectiveness. Regular maintenance and cleaning of solar panels are crucial to prevent cementation and ensure optimal performance – keeping the panel surfaces clean and free from debris. 

How to prevent cementation (without a brush!)

It might seem that cementation is inevitable, and removing it must require some form of agitation – a rotating or vibrating brush perhaps. Wrong! If you’re hiring manual cleaners to retroactively remove cementation from your panels with abrasive tools from a highly scratchable surface, you’re doing solar panel cleaning wrong. Here’s why:

It’s possible to keep your panels clean all the time and prevent cementation from occurring in the first place – just install an active panel cleaning solution like RST NightWash™. 

RST’s patented system utilizes tried and tested irrigation technology, using low water pressure to clean solar panels at night. No brushes, no chemicals – just soft, pure filtered water.

2022 report from the International Energy Agency recommends, automated solar panel cleaning systems like RST NightWash™ that deploy “sprinkler”-like cleaning techniques are a recommended choice for nearly every environment:

  • Dry
  • Cold, moist
  • Hot, arid, sunny
  • Cloudy, shaded

No need to jeopardize panel warranty with an aggressive agitator (studies show that in some cases, considerable damage can be caused by brushes due to the abrasive nature of the contamination). Simply install RST NightWash™ and watch your production increase with zero risk of voiding your panel warranty.

Avoid cementation and soiling losses with RST NightWash™

Choosing the right solar panel cleaning system can truly be a make-or-break decision, especially when it comes to large-scale commercial solar projects that rely on maximum production for faster ROI. Avoid cementation and improve the economics of your solar project by keeping your solar panels clean all the time with RST NightWash™.


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