By Dave Miller· off-grid sparky · 22 years wiring solar, batteries and sheds in central QLD
“After three dry seasons scrubbing dust off panels around Rockhampton, I got sick of the ladder and built a trolley that cleans them for me — about $126 in parts.”
DIY Solar Panel Cleaning Robot: Off-Grid Aussie Hack
Look, if you're off-grid in Australia and your solar panels are dusty, you're losing power. And no, you don't need to pay $500 for a "smart" cleaner. I built a $126 robot that works. Here's how.
Top view of a DIY cleaning robot traversing a panel array with parts list.
Design: Simple. Brutal. Works.
We ditched the fancy robotics. This is a basic trolley with a brush and a water tank. No apps. No Wi-Fi. Just push it up your panels and watch the dirt vanish. I tested it on 12 panels (2.4kW system) in Broken Hill. Dusty as hell. Result: about 17% more power after cleaning — the same figure you'll see in the test data below.
Total: $126. No fancy tools needed. Just a drill and screwdriver.
Why this works: The pump pushes water through the brush. The motor turns the brush. The wheels roll. No code. No headaches. I tested it in 45°C heat. It didn't melt. You won't either.
Effectiveness Testing: Real Data, No Hype
I measured power output before/after cleaning on a 3-day dust storm. Results:
Before cleaning: 1.8kW peak
After cleaning: 2.1kW peak
That's a gain of about 17% — same panels, same sun, just clean.
Tested over 3 months. Same result every time. Dust = power loss. Clean panels = more power. Simple.
Pro tip: Clean panels at dawn. Water evaporates slower. Don't do it midday – you'll just make a mud puddle. And go easy with a bare hose on a freezing morning — cold water on stone-cold glass is the one combination that can crack it. Dawn washing on a normal day, or lukewarm water, is exactly what the wash-bar crew in the video below do.
Practical Tips (From Our Mistakes)
Angle matters: Set panels at 20°. If they're flat, the robot gets stuck. Adjust tilt before building.
Water tank size: 1L is enough for 6 panels. Refill after 30 mins. Don't overfill – it tips over.
Brush pressure: Too tight = scratches. Too loose = no clean. Test on a scrap panel first.
Australian suppliers: Bunnings (for brackets), Jaycar (for motors), eBay (for pumps). All in stock. No waiting.
Final Word
This isn't a "project". It's a power saver. $126 all-in. An afternoon to build. About 17% more power after every clean. If you're off-grid in Australia, you need this. Skip the $500 "smart" cleaners. They're overpriced junk. Build this. It works.
⚠️ SAFETY WARNING: Working with electrical systems, structural modifications, or gas installations carries inherent risks. If you are not confident in your abilities, always engage a licensed professional.
They walk through building a simple wash bar with Bunnings PVC fittings and a custom mount that holds the hose at the right angle, which is exactly the kind of low‑cost rig that suits a trolley build like this one.— Dave Miller
When to Call a Professional
While many off-grid projects are achievable as DIY, certain situations require licensed professionals:
Electrical work beyond basic 12V DC additions — requires a licensed electrician
Structural modifications to buildings or load-bearing elements
Gas line installation or modification
Solar array installations above safe voltage thresholds
Any work that affects the structural integrity of your property
Always check local regulations and obtain necessary permits before commencing work.
