How to Clean Your Home Solar Panels Yourself and How Often
You can do it yourself if the roof is safe to reach — just clean water and a soft cloth, system off, panels cool. This page gives the step-by-step method, the right frequency for your area, how much output dust costs you, and when to hire a professional instead.
Yes, you can clean home solar panels yourself if you can reach the roof safely. Use only clean water and a soft cloth or a squeegee — no high-pressure jets and no harsh chemicals — switch the system (inverter) off first, and wash in the early morning or evening while the panels are cool. Typically clean 1–2 times a year (more if you are near a dusty road, construction, or in a long dry spell). Settled dust cuts output by about 3–5%, and up to 15–25% with heavy dust or bird-dropping spots. If the roof is high or steep, hire a professional — it is safer.
Can I clean solar panels myself, what do I use, and must I switch the system off?
| Item | ✅ Do | ❌ Don't / caution |
|---|---|---|
| Water & solution | Clean/tap water (mild soap if needed) | High-pressure jets, harsh/abrasive chemicals, solvents |
| Tools | Soft microfibre cloth, squeegee, soft-bristle brush on a pole | Wire brush, abrasive pads, anything that scratches the glass |
| Timing | Early morning or evening, panels cool and damp | Midday strong sun / hot panels (streaks + crack risk) |
| Safety | Inverter off first, work from the ground/long pole, don't stand on panels | Spraying water into connectors/junction box, climbing a high/steep roof alone |
Cleaning solar panels: do's vs don'ts
How often should I clean solar panels (how many times a year)?
| Environment | Suggested frequency | Output lost (approx.) | Bill/yr (5 kW home, ~4 THB/unit) |
|---|---|---|---|
| Typical city, regular rain | 1–2×/year | ~3–5% | ~1,000–1,400 THB |
| Near dusty road/construction/factory | Every 3–4 months | ~5–10% | ~1,400–2,800 THB |
| Dry area/long dry spell, or bird droppings-leaves | Every 2–3 months / when soiled | ~10–25% | ~2,800–5,600 THB |
How much does it cost to hire someone to clean solar panels (per panel / per kW)?
If I never clean the panels, how much output do I lose — and is it harmful?
More on long-term degradation and panel lifespan at how much do solar panels degrade per year.
Cleaning your solar panels yourself, step by step (5 safe steps)
Follow this order to stay safe and avoid damaging the panels:
Pick a time when panels are cool
Wash early morning or evening; avoid strong midday sun — a hot panel hit with cool water risks cracking, and water dries into streaks.
Switch the system off first
Turn off the inverter and breaker in the order given in the manufacturer's manual for electrical safety before you touch or spray water near the panels.
Brush off dry dust/leaves first
Use a soft-bristle brush on a pole to sweep off coarse dust, leaves and debris first, so they don't scratch the glass during the wet wash.
Rinse with clean water
Pour clean water and wipe with a soft cloth or squeegee, top to bottom — no high-pressure jets, no harsh chemicals — and never spray into the connectors/junction box.
Check output + height safety
Let it dry, switch the system back on, and check in the app that output has recovered. If the roof is high or steep, don't risk climbing — hire a professional with ropes/safety harness.
Clean it yourself or hire? Judge by these 5 things
There is no single answer — decide mainly on safety and value:
Roof height & pitch
A single-storey, low-pitch roof reachable from the ground/ladder = fine to DIY; a high, steep or slippery roof = hire a pro. Safety comes first.
System size / panel count
A few panels are quick to DIY; a large array of dozens is faster to hire out, and you get a system check thrown in.
Warranty / manufacturer terms
Read the manual — some brands specify the cleaning method or require an approved technician to keep the warranty; chemicals/high pressure usually void it.
Safety gear & confidence
If you lack ropes/harness, a stable ladder and confidence at height, don't force it — a service fee is cheaper than an injury.
Stubborn soiling / water quality
Greasy film, tree sap or hard-water spots that plain water won't remove may need a pro with deionised water/proper kit to avoid leaving marks.
Large system, high roof, or a building/factory?
Author & review
Written and reviewed by the CapSolar engineering team (solar EPC & O&M), citing manufacturer care guidance and utility knowledge sources (PEA Solar / MEA / SafeSaveThai). Figures with no official announcement are given as ranges with their basis — last verified 23 Aug 2026.
FAQ
Want your home solar producing at its best?
Talk to CapSolar about care, cleaning and output checks — or send your bill for a system assessment for your home.