Cleaning systems matched to your modules and your chemistry

We design cleaning systems for plants: the brushes and machines, the dosing, the water treatment and storage, and the crew procedure that ties them together. We specify the equipment, check it against your module maker’s conditions and can supply dosing pumps and other cleaning equipment. Your crews or O&M contractor run the system; we train them and write the method statement, as part of the cleaning strategy. Crews that only need Chemitek products can order just the products.

Why the equipment matters. The wrong tool leaves soiling behind, wastes water or breaks the module maker’s cleaning conditions, which differ between makers. Dry brushes have caused considerable damage to some anti-soiling coatings (IEA PVPS 2022). The right choice depends on the soiling and its rate, the water, site access, the mounting (tracker or fixed tilt, roof or ground), labour and the contract (Ilse et al. 2019). So every design starts with your module manual and a look at the site.

On utility-scale rows with access roads, tractor-mounted brushes are a common fit. Rooftops and carports suit water-fed poles, manual brushes or drone cleaning where access is unsafe. On floating PV, Chemitek states Solar Wash Protect is certified as safe for use.

Matching equipment to the module maker’s conditions. Pressure, brush type, machine weight and whether robots or motorised tools are allowed all sit in your module maker’s manual. Warranty-safe methods sets those limits out. A letter of conformity covers the product, and the tools still have to meet the manual. JA Solar’s 2025 letter for ten Chemitek products says it is not liable for damage caused by cleaning tools.

Chemitek sets how each product goes on, machine by machine:

Loose dust comes off with most methods. Bonded soiling needs a removal agent, with harder bristles where the module maker allows them (Chemitek). A dry robot can’t restore cured cement; a wet robot or tractor can, with a sprayer ahead. See cement dust.

A dosing pump holds the ratio across a whole site. Chemitek specifies water-powered pumps by product: a 0.03–0.3% model for Antistatic Solar Armor 2.0, D-Solar Defendor and Water Softening Agent, and a 0.2–2% model for Solar Wash Protect 50. A bypass switches the crew to plain water for rinsing, and pumps of this type are limited to 6 bar.

For hard water, Chemitek’s set-up puts a sediment and activated-carbon filter ahead of the pump that doses Water Softening Agent, with a dynamic mixer after it, and quotes up to 3,000 L of softened water an hour with no power supply. We check the water after the mixer with hardness test strips, because a TDS meter reads the softener itself and says nothing about hardness. See water testing.

• Tractor brush, Chile. At a 115 MWc single-axis tracker plant, D-Solar Defendor was mixed into the wash water and brushed onto three strings. Over six months, October 2020 to March 2021, they produced 2.41% more energy than three strings cleaned with water, and the tractor ran at 1.35 km/h instead of 1.1 km/h on the dry cleans that followed. Read the case study.
• Robot, Vietnam. On a 330 MW site, D-Solar Defendor was injected over the robot’s brushes. Three more cleans followed without reapplying it, the robot could run softer brushes and water use fell 15–25%. Read the case study.

For a ±15.6 MWp plant beside a cement works in North West Province, we built the equipment around the chemistry. A three-person relay crew works each row: one sprays Inorganic Removal Agent from a backpack sprayer, one agitates with a battery-powered dual rotating brush, which can brush without water where water-driven heads can’t, and one rinses with a water-fed rotating brush on softened water. A second, quick pass coats the clean row, with a dosing pump metering Antistatic Solar Armor 2.0 into the water and no rinse. See the programme or read the case study.