When And How Should I Clean My Solar Panels?
Solar Panel Cleaning & Care Guide
Protect your investment and keep your system performing at its best
A solar panel system is a long-term investment in your home and your energy future, so it makes sense to look after it properly.
The good news? Solar panels are very low maintenance.
But like anything exposed to the elements year-round, an occasional clean can help keep them running efficiently and ensure you’re getting the most out of your system for years to come.
Do solar panels actually need cleaning?
Most of the time, nature does the job for you.
Because panels are installed on an angle, rain will usually wash away everyday dust and dirt.
However, in areas with lots of dry weather, coastal salt, farming activity or heavy pollen (which is common across Hawke’s Bay) grime can slowly build up on the surface.
Things like:
pollen
dust and sand
bird droppings
salt spray
leaves and debris
can all block sunlight from reaching the cells.
And here’s something many people don’t realise…
Your system is only as strong as its weakest panel
Solar panels work together as a team.
So if even one panel is heavily soiled or underperforming, it can affect the output of the entire string, meaning the rest of your system can’t perform at its full potential either.
In some cases, build-up can reduce production by 10–20% or more.
If you notice your system isn’t producing as much as it used to, a clean may help restore performance.
General cleaning tips
1. Turn your system off first!!!
Safety always comes first.
Before cleaning, switch off both the AC and DC isolators. Water and electricity don’t mix, so this step is essential.
2. Clean from the ground where possible
If you can safely reach your panels from the ground using an extension pole and soft brush, this is the best option.
Use:
Clean water
A soft brush or sponge
A gentle squeegee
Avoid anything abrasive that could scratch the glass.
3. Avoid climbing onto the roof
Roof work can be risky, especially with water and equipment.
If your panels can’t be reached safely, we recommend hiring a professional rather than attempting it yourself. Many roof or exterior cleaning companies have the right tools and safety gear.
Or simply get in touch with Zeus Solar & Electrical we’re happy to help.
4. Choose the right time of day
The best time to clean your panels is:
Early morning
Late afternoon
Overcast days
Cleaning in full sun can cause water and cleaning products to dry too quickly, leaving residue behind that can reduce efficiency.
Morning is ideal, as dew will often have already softened any dirt or pollen.
5. Keep it gentle
Solar panels are tough, but the surface still needs care.
Stick with:
Water
Soft brush or cloth
Very mild detergent if needed
Avoid:
Harsh chemicals
Abrasive pads
Pressure washers
Hard scrubbing
Scratches can permanently reduce performance.
6. Turn your system back on
Once finished, switch everything back on and check your system is running normally.
Prefer a professional clean?
If you’d rather leave it to the experts, we’ve got you covered.
At Zeus Solar & Electrical, we provide professional solar servicing and panel cleaning throughout Hawke’s Bay to keep your system safe, efficient, and producing at its best without you needing to climb onto the roof.
If you have questions or want help maintaining your system, get in touch anytime.
👉 Book a service or chat with our team
