Solar panel cleaning is not only about removing visible dust. For PV O&M teams, the real question is whether the cleaning method protects module surfaces, avoids residue, fits site logistics and creates measurable energy improvement.
Quick answer: use clean, low-mineral water whenever possible, control spray distance and pressure, choose nozzle layout based on site and module condition, and avoid detergents unless they are compatible with the PV module manufacturer’s guidance. DI or RO water can help reduce mineral residue, but the right water strategy depends on site conditions and cost.
Who This Guide Is For
This guide is for:
- PV O&M teams
- Solar cleaning contractors
- EPCs and asset owners
- DJI T100 Solar Cleaning Kit buyers
- Solaris C60V buyers
- Agricultural drone service teams entering solar cleaning
Why Water Quality Matters
High-mineral water can leave residue after drying. On PV glass, residue can reduce transparency, create visible streaks and make the cleaning result harder to evaluate.
Low-mineral water, RO water or DI water can reduce this risk. The correct choice depends on:
- Local water hardness
- Module manufacturer guidance
- Cost of water treatment
- Site refill logistics
- Soiling type
- Whether cleaning is done in hot sun or cooler periods
DI Water vs RO Water
| Water Type | Practical Meaning | Best Use |
|---|---|---|
| Tap water | Locally available, quality varies | Only when mineral content is acceptable and module guidance allows |
| Filtered water | Removes particles depending on filter | Basic cleaning support |
| RO water | Reverse osmosis reduces dissolved minerals | Good default for many PV cleaning programs |
| DI water | Deionized water with very low mineral content | Best when residue/streaking risk must be minimized |
Do not assume every site needs DI water. For many projects, RO water may be a practical balance between quality and cost. For sensitive or high-value sites, DI water may be worth the extra logistics.
Pressure Is Not the Goal
High pressure can help remove stubborn dirt, but PV modules are not concrete floors. Excessive pressure, wrong angle or close nozzle distance may create risk around:
- Glass surface coatings
- Edge seals
- Frame joints
- Junction boxes
- Cables and connectors
- Already damaged modules
The goal is controlled cleaning, not maximum force.
Nozzle Layout Matters
Nozzles determine spray distribution, coverage and working distance.
For the EAUAV T100 Solar Cleaning Kit, the current second-generation design uses six fixed nozzles for a stable solar cleaning layout.
For Solaris C60V, EAUAV offers two spray layout options: a compact 4 downward-swing nozzle layout and a folding extension rod with 2 nozzles, depending on site clearance and operator preference.
The best nozzle layout depends on:
- Panel tilt
- Row spacing
- Flight height
- Wind
- Soiling type
- Desired spray overlap
- Aircraft clearance
Cleaning Timing
Cleaning during cooler periods can reduce rapid evaporation and thermal stress. Midday cleaning in strong sun can make water dry too quickly, leaving mineral residue or streaking if water quality is poor.
Better planning windows often include:
- Early morning
- Late afternoon
- Cloudy but safe conditions
- Periods with manageable wind
Final timing should also consider site access, electrical safety and local operating approvals.
Soiling Types and Cleaning Strategy
| Soiling Type | Cleaning Note |
|---|---|
| Dust | Often manageable with clean water and repeatable coverage |
| Pollen | May require more careful timing and water volume |
| Bird droppings | May need pre-wetting, contact time or manual follow-up for stubborn spots |
| Salt | Water quality and rinse completeness matter |
| Industrial pollution | Review chemical compatibility and module warranty guidance |
| Mixed soiling | Test a small area and document results before scaling |
T100 Kit vs C60V Water Strategy
The T100 Solar Cleaning Kit is a conversion path for DJI Agras T100/T70 platforms. It uses an onboard-tank Agras workflow and is attractive when the buyer already owns or can locally source DJI aircraft.
The Solaris C60V is a complete 60 L solar cleaning drone system with two spray layout options and a mobile free-flight workflow.
In both cases, water quality and cleaning SOP matter as much as the drone.
How to Avoid Bad Cleaning Claims
Do not claim:
- “Guaranteed power increase”
- “Safe for every solar panel”
- “No risk to modules”
- “Works with any detergent”
- “No operator training required”
Use better language:
- “Cleaning effect should be measured with site data.”
- “Confirm module manufacturer cleaning guidance.”
- “Test a small area before routine operation.”
- “Use low-mineral water when residue risk matters.”
Pre-Job Checklist
Before cleaning, confirm:
- Module manufacturer cleaning guidance
- Water source and mineral content
- Whether RO/DI treatment is needed
- Spray distance
- Pressure setting
- Nozzle layout
- Panel condition
- Wind and temperature
- Electrical safety controls
- Drone operating permission
- A/B test or production data comparison plan
FAQ
Is DI water always required?
No. DI water is useful when residue risk must be minimized, but RO or other low-mineral water may be sufficient depending on site and module guidance.
Can I use tap water?
Only if water quality is acceptable and does not leave problematic residue. Test before routine operation.
Can drones remove bird droppings?
Some fresh or softened bird droppings may be removed with water spray, but hardened deposits may require pre-wetting, repeat pass or manual follow-up. Do not guarantee removal without testing.
Is higher pressure better?
No. Pressure must be matched to module condition, nozzle distance, spray angle and warranty guidance.
Can detergents be used?
Only if compatible with module manufacturer guidance and tested safely. Clean water should usually be the default starting point.
How do I prove cleaning worked?
Use A/B testing, kWh/kWp comparison, inverter data, irradiance normalization or soiling measurement. Do not rely only on photos.
Which EAUAV product should I choose?
Choose T100 kit if you already own or can locally source DJI Agras T100/T70. Choose Solaris C60V if you want a complete solar cleaning drone system.
What should I send EAUAV?
Send site type, MW capacity, panel layout, soiling type, water source, country, aircraft ownership and target cleaning schedule.
Conclusion
A good solar cleaning drone workflow starts with module-safe cleaning logic. Water quality, pressure, nozzle pattern, timing and measurement determine whether the operation is repeatable.
Ask EAUAV to Review Your Solar Cleaning Water and Nozzle Strategy
