3 Signs Your Solar Panels Need Cleaning

In a city blessed with as much sunshine as Perth, installing solar panels is a smart investment. But to get the maximum return on that investment, your panels need to be performing at their peak.

Over time, a layer of dust, grime, bird droppings, and salt spray can build up, significantly reducing their efficiency. But how do you know when it's time for a clean?

Here are three key signs that your solar panels are due for a professional clean and how neglecting them could be costing you money.

1. A Visible Layer of Dust or Grime

This is the most obvious sign. While a light layer of dust is normal, if you can see a noticeable, hazy film, patches of dirt, or bird droppings from the ground, your panels are not absorbing as much sunlight as they should be.

In Perth's dry summers, this buildup can happen surprisingly quickly. Studies have shown that dirty solar panels can lose anywhere from 5% to 25% of their efficiency, which translates directly to a smaller credit on your power bill.

2. A Noticeable Drop in Your System's Output

Most modern solar systems come with a monitoring app or an online portal that shows you how much energy your system is producing. A key sign that your panels need cleaning is a gradual, unexplained drop in performance, especially on clear, sunny days.

If you compare your output from this month to the same month last year and see a significant decrease (and there have been no major equipment issues), a professional clean is often the most cost-effective way to restore that lost performance.

3. It's Been Over 12 Months Since Your Last Clean

Regular maintenance is key. Most solar panel manufacturers and clean energy experts in Australia recommend having your panels professionally cleaned at least once every 12 months.

For homes in particularly dusty areas or close to the coast where salt spray is a factor, cleaning every 6-9 months can provide an even better return. Think of it like servicing your car; regular cleaning is a small investment that protects your larger investment and ensures it runs at peak efficiency for years to come.