Australia has more rooftop solar than almost anywhere on earth. Over 3.5 million homes have panels on the roof, and on the Sunshine Coast the numbers are even higher than average. We have the sunshine, the power bills and the rooftops to make it worthwhile.
But here’s what most people don’t realise: a solar system isn’t “set and forget”. Our beautiful coastal climate, with its salt air, humidity, storms, pollen, bushfire smoke, birds and bats, is tough on solar panels. Many of the most common problems we see are either caused or made worse by one simple thing: panels that haven’t been cleaned in years.
Here are the seven most common solar panel problems in Australia, and what you can do about them.
1. Dirt, dust and grime build-up (soiling)
This is the big one. Every day your panels collect a fine layer of dust, pollen, soot, road and construction dust, and general airborne grime. Rain washes off some of it, but not all. In fact, light showers can turn dust into a muddy film that dries into a stubborn crust, especially along the bottom edge of the panel where water pools.
Why it matters: Dirt blocks sunlight from reaching the solar cells. Depending on your location, roof pitch and how long it’s been, soiling can noticeably reduce your system’s output, and the losses are often bigger than people expect. You’re still paying for a system that’s producing less than it should, and you won’t see it on your power bill until you compare months or years.
The fix: Regular professional cleaning. A clean panel simply lets in more light.
2. Bird droppings
Bird droppings are one of the worst offenders, and not because of the volume of dirt. It’s because they’re concentrated in one spot. Panels are made up of cells wired together in series, and when a single cell or section is blocked, it can drag down the output of the whole string.
Bird droppings are also acidic and can bake onto the glass in our hot sun, which makes them very hard to remove without the right tools and technique. Rain won’t touch them.
Magpies, lorikeets, ibis, cockatoos and pigeons are all regular culprits on the Sunshine Coast.
The fix: Prompt removal with soft brushes and purified water, and, if birds are nesting under your panels, bird-proofing mesh (more on that below).
3. Salt spray and coastal grime
If you live anywhere near the ocean, from Mooloolaba to Noosa to Caloundra, your panels are copping a daily dusting of salt-laden air. Salt crystallises on the glass, attracts more dust, and can speed up corrosion on frames, mounting rails and fixings over time.
Salt build-up is also one of the reasons panels near the coast often need cleaning more often than those inland.
The fix: More frequent cleaning for coastal homes. Many coastal homeowners benefit from having panels cleaned at least once or twice a year, rather than waiting until they notice a problem.
4. Mould, algae and lichen
The Sunshine Coast’s warm, humid, subtropical climate is perfect for growing things, including on your roof. Mould, algae and lichen love shaded sections, the lower edges of panels and the gaps around frames where moisture sits.
Left alone, they spread. They block light, trap moisture against the frame, and can be difficult to remove once they’ve taken hold.
The fix: Gentle, panel-safe cleaning before growth gets established. Harsh chemicals, abrasive brushes and high-pressure water are a no-go, as they can damage the anti-reflective coating on the glass and may void your warranty.
5. Hot spots
A hot spot happens when part of a panel is shaded or blocked (by a patch of bird droppings, a pile of leaves or a stubborn stain) and that cell starts to overheat as it’s forced to carry current from the cells around it.
Hot spots reduce performance and, over time, can permanently damage the cell, the panel’s backing material or the bypass diodes. In rare cases they’re a fire risk.
The fix: Keep the surface clean and free of debris, keep trees trimmed, and have your system inspected if output drops suddenly or unexpectedly. Thermal imaging can spot hot spots that aren’t visible to the naked eye.
6. Leaves, debris and animal nesting
Overhanging trees drop leaves, seed pods, sticks and sap onto panels, and all of it can collect against the lower frame. Debris that builds up at the bottom of a panel can hold moisture against the surface and block water from running off properly.
Under the panels, possums, rats, mice and birds love the warm, sheltered gap, and they can chew wiring, build nests and leave droppings that damage cables and create a fire hazard.
The fix: Regular cleaning and a quick visual check of the area around and beneath the panels. If you’ve got critters, install proper wire mesh around the array edge (a licensed installer can do this).
7. Storm, hail and wear-and-tear damage
Southeast Queensland storm season can be brutal. Hail, high winds, flying debris and lightning can all cause microcracks, cracked glass, loose fixings and damaged inverters. Microcracks are especially sneaky because they’re often invisible from the ground, but they reduce output and tend to get worse over time.
Other age-related issues include inverter faults, failing isolators, discolouration or delamination of panels, and loose or corroded wiring.
The fix: After any major storm, check your monitoring app for unusual drops in production and consider a professional inspection. Cleaning is also a great opportunity to spot damage early: our team can see cracks, loose fixings and discolouration up close, and let you know if you should call a solar technician.
“But doesn’t the rain clean my panels?”
This is the most common thing we hear, and it’s partly true. Rain does wash off some loose dust. But rain on its own:
- Doesn’t remove bird droppings, sap, salt film, mould or baked-on grime
- Often leaves dirt lines and streaks, especially along the bottom edge of panels
- Can turn dust into a film that then dries in place
- Is unreliable. Long dry spells, bushfire smoke seasons and coastal salt all build up faster than rain can handle.
Panels with a low tilt (common on Australian roofs) hold onto dirt even more because water doesn’t flow off them as quickly.
What happens when you don’t clean your panels?
If you skip cleaning year after year, you’re likely to see:
- Lower energy production, so you’re buying more power from the grid than you need to
- A longer payback period on a system you’ve invested thousands in
- Hot spots and uneven wear, which can shorten the life of your panels
- Harder-to-remove stains, as grime bonds to the glass over time
- Missed warning signs, because small issues like cracked glass, loose fixings or nesting animals go unnoticed
- Possible warranty headaches, as some manufacturers expect panels to be properly maintained (check your warranty documents)
In short: you’ve invested in a system designed to save you money, and dirty panels quietly work against that.
How often should you clean your solar panels?
There’s no single answer, but as a rough guide for the Sunshine Coast:
| Situation | Suggested cleaning |
|---|---|
| Coastal homes (salt spray) | Every 6 months |
| Near trees, bushland or lots of birds | Every 6 months |
| Inland or suburban, low-tilt panels | Every 6–12 months |
| After bushfire smoke, storms or construction nearby | As soon as practical |
If you’re not sure, a quick comparison of your production on a sunny day now against the same time last year can be revealing. If it’s dropped without a good reason, dirt is often the first thing to check.
Why not just do it yourself?
It’s tempting, but cleaning solar panels isn’t as simple as hosing them down:
- Safety: Roofs are dangerous, and falls from roofs are a leading cause of serious injury in Australian homes. Panels can also be slippery when wet.
- Damage risk: Pressure washers, harsh detergents and abrasive tools can scratch glass, strip coatings and force water into seals, which may void your warranty.
- Hard water spots: Tap water leaves mineral deposits, which is why professionals use purified water and soft brushes.
- Heat: Cold water on hot panels can cause thermal stress. Timing matters.
- Electrical safety: Solar systems are live whenever the sun is out. Water and electricity need proper care.
A professional clean is safer, more thorough and designed not to put your warranty at risk.
Keep your panels working as hard as you do
Your solar panels are a serious investment, and they deserve a little care to deliver the savings you were promised. Regular cleaning is one of the easiest, cheapest ways to protect your output, catch problems early and get the most out of your system for years to come.
Ready for a clean? Sunshine Coast Solar Panel Cleaning services homes and businesses across the Sunshine Coast. Get in touch today for a free, no-obligation quote and let us get your panels back to peak performance.