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Clean efficiently with the right water strategy

Water pressure and water volume for cleaning large PV systems

For operators of large photovoltaic systems

Professional cleaning of large PV systems isn’t just about water pressure. What matters is the interplay of sufficient water volume, low pressure, and the right hose technology. Too little water, pressure losses over long distances, or incorrectly sized hoses can impair cleaning performance. With a water strategy tailored to the system, dirt can be effectively removed while protecting sensitive module surfaces.

Problem: Poor cleaning due to incorrect water usage

Operators of large photovoltaic systems face a recurring technical problem:

  • Many cleaning methods use too little water or utilize high-pressure cleaners – which may seem powerful for solar modules, but can damage the sensitive glass surface.
  • Pure low pressure on smooth PV surfaces can cause abrasion from dirt particles without a sufficient water volume, instead of dissolving them.
  • Furthermore, height differences and long hose distances lead to water pressure losses that reduce the cleaning effect.
  • Incorrectly sized hoses further reduce water throughput and thus the cleaning performance.


→ Studies on PV cleaning techniques recommend adjusted water volumes and suitable pressure to optimize cleaning efficiency and module protection.

"For large PV systems, the key isn't the highest possible water pressure, but rather a consistent and sufficient water flow. The right combination of water volume, low pressure, and hose technology creates the foundation for effective yet gentle cleaning."

Solution: Low pressure + sufficient water volume + correct hose technology

For effective and gentle cleaning, water pressure and water volume must be coordinated. Equally important is ensuring that the water reaches the cleaning device with sufficient flow even with elevation differences and long hose runs. In practice, three factors are therefore crucial:

1. Pre-cleaning and main cleaning with water

For optimal results, pre-cleaning and main cleaning with water is recommended, ideally with osmosis water: Osmosis water is free of salts, minerals, and residues and provides gentle yet effective cleaning without additives. The filtered water creates a flushing effect that gently loosens dirt without rubbing. Benefit: Gentle dirt removal, lower risk of scratching, and less post-cleaning required.

2. Low-pressure range instead of high pressure

Solar cleaning robots work effectively in the low-pressure range (approx. 2–4 bar) – this is roughly the same as a standard tap connection. Low-pressure cleaning ensures the surface of the modules is not damaged. Benefit: Gentle cleaning without risk to module glass or seals.

3. Consider water pressure losses and hose diameter

Pressure losses are caused by: Height differences: Rule of thumb: ~1 bar pressure loss per 10 m height Long hose lengths and small internal diameters: reduce water throughput hyCLEANER recommends supply hoses with an internal diameter of at least 10 mm for the solarROBOT series to ensure sufficient water flow. Benefit: Constant water pressure and higher cleaning effect across the entire system.

Advantages of the correct water strategy

ChallengeSolutionResult
Dirt rubs instead of dissolvingOsmosis water + sufficient water volumeLess abrasion & cleanliness
Pressure lossesRight hose + pressure planningConsistent cleaning
Module risksLow pressure instead of high pressureNo surface damage

Which cleaning solution fits your PV system?

Whether it’s an agricultural rooftop system, a commercial roof or a large solar park—the economically optimal cleaning solution depends on system size, location and degree of soiling. Together, we analyze your system and recommend the right cleaning concept.

Our cleaning solutions at a glance

For agricultural as well as small and medium rooftop systems up to approx. 200 kWp. The cleaning robot can be used independently by the system operator and is supplied including a charging station. CE-certified and developed specifically for cost-effective in-house operation.

For medium-sized commercial and ground-mounted systems. With a working width of up to 2 meters and semi-automated operation, the solarROBOT Pro is ideal for efficient cleaning of larger module areas.

For large-scale systems and ground-mounted projects. With a working width of 2.4 meters, maintenance-free chain drive and high area performance, the solarROBOT Ultimate was developed for professional use on large PV systems.

The handheld cleaning solution for special constructions, complex roof geometries and professional cleaning service providers. Ideal for applications where cleaning robots cannot be used due to the design.

All systems clean without chemicals or soap using pure water and enable gentle, material-friendly cleaning of PV systems.

Get in touch.

We analyze your system portfolio, calculate your individual cleaning needs and recommend the economically optimal cleaning concept—from a single system to a multi-site park.

Published: 25.02.2026
Last reviewed: 09.09.2026
Reading time: 5 Minuten

Table of Contents

How badly is your system affected?

Calculate your individual yield loss with the hyCLEANER solar loss calculator.

Individual Offer

We recommend the economically right cleaning concept for your system.

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