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Abstract: In the field of photovoltaic (PV) module cleaning, brush bristles are the “frontline workers” in direct contact with the glass surface. Subtle differences in their material, hardness, and manufacturing process directly determine PV cleaning effectiveness, module safety, and equipment longevity. Delving deep into the science of PV cleaning, WaterSprayElephant rejects the industry’s one-size-fits-all approach. We scientifically match PBT and Nylon materials to specific PV cleaning scenarios—dry cleaning, wet cleaning, and different types of stubborn soiling—and employ advanced integrated tufting technology. This achieves the perfect balance between PV cleaning power, module protection, and brush durability.
Effective PV module cleaning is far more than a simple “scrubbing” motion. With every rotation of the brush head, the material and properties of the bristles silently define the outcome: is it a thorough renewal of the power-generating surface, or does it risk scratching the glass? The crude and uniform bristle selection found in many PV cleaning tools on the market today has become a key bottleneck restricting PV cleaning quality and safety.

Three Major Limitations of Generic Market PV Cleaning Brush Bristles

  1. Hardness Imbalance, Hidden Damage Risk: Many PV cleaning products, in pursuit of cleaning power, use excessively hard bristles. At high motor speeds, these bristles act like microscopic “sandpaper,” which can easily create micro-scratches on the PV module surface over time. These scratches not only affect aesthetics but also cause light scattering, leading to potential losses in solar energy yield.
  2. Too Soft, Ineffective Against Stains: Conversely, bristles that are too soft prove inadequate when facing dried bird droppings, mud stains, or mineral deposits—stubborn soiling in PV cleaning. Cleaning effectiveness is compromised, forcing operators to clean repeatedly and reducing solar farm maintenance efficiency.
  3. Single Material, Scenario Mismatch: A more common issue is the use of the same bristle type for both dry dust and sticky grime, for both dry and wet PV cleaning. This “one-brush-fits-all” strategy fails to adapt to complex and variable field conditions, inevitably resulting in suboptimal PV cleaning.

WaterSprayElephant’s Solution: Scientific Bristle Material Matching Based on PV Cleaning Scenarios

We believe bristles are not mere consumables but core components of precision PV cleaning tools. Our bristle selection is based on deep materials science and PV field condition research:
  1. Dual-Material Strategy for Diverse PV Cleaning Challenges:
    1. PBT (Polybutylene Terephthalate): Characteristically stiffer and offers good toughness. Ideal for wet PV cleaning scenarios and handling tenaciously adhered substances (e.g., dried bird droppings). We carefully select medium-hardness PBT bristles, ensuring powerful contaminant removal while minimizing the risk of PV module surface damage.
    2. Nylon: Characteristically softer and extremely wear-resistant. Particularly suitable for dry PV cleaning scenarios, it gently sweeps away dust and sand particles, preventing dry, hard granules from “grinding” against the glass under the brush’s action. We typically select extra-soft nylon filaments with a diameter under 0.3mm for gentle yet effective PV cleaning.
  2. Process Innovation, Phasing Out Obsolete PV Cleaning Brush Technology:
    1. We have completely phased out older brush heads using the woven-cord process. In this process, the binding cord is prone to detachment, harbors dirt, has a short lifespan, and provides inconsistent PV cleaning results. As shown in the figure below:
    2. We have fully adopted the advanced integrated tufting process. Each filament is securely and uniformly implanted into the brush head base, with no metal wires or woven fabric involved. This delivers unparalleled durability, consistent PV cleaning performance, and high reliability, completely eliminating the risk of debris detaching and contaminating the PV modules or equipment. The improved design is shown in the following figure:

 

Field Test Results: Precision Bristle Selection for Excellent PV Cleaning Performance

Tested in harsh environments such as desert power plants in the Middle East (dealing with fine sand) and coastal plants in Southeast Asia (dealing with salt residue), our scenario-based PV cleaning bristle solution has proven highly successful:
  • In dry cleaning mode, nylon bristles remove dust gently and efficiently, leaving the PV module surface clean and streak-free.
  • In wet cleaning and for tackling stubborn stains, PBT bristles demonstrate powerful PV cleaning capability, quickly restoring module surface clarity.
  • The integrated tufted brush heads maintain stable performance throughout their lifecycle, with no shedding or deformation, resulting in extremely low PV cleaning maintenance costs.
This embodies WaterSprayElephant solutions’ commitment to customized solar cleaning and smart O&M for photovoltaic systems.

About WaterSprayElephant

 

WaterSprayElephant is a technology company dedicated to the R&D and manufacturing of intelligent cleaning solutions for PV modules. We believe true efficiency innovation stems from a deep dive into every technical detail. From the bristle selection in our handheld cleaning brushes to the obstacle-crossing algorithms in our tracked cleaning robots and the system integration in our horizontal cleaning robots, we are committed to providing full-scenario, high-performance PV module cleaning systems. Our website: watersprayelephant.com

 

Our mission is to make PV cleaning labor easier and, through our expertise, help increase solar energy yield and reduce solar O&M costs, becoming a trusted efficiency innovation partner for our global clients.

 

Our Mission is to “Make PV Cleaning Labor Easier.”

Our Vision is to become the technology leader in enhancing photovoltaic power generation efficiency.

By Published On: April 3, 2026