Solar panel maintenance: keeping an installation generating
A rooftop solar array has no moving parts, which is a large part of why it lasts decades. What it does need is periodic cleaning, occasional inspection, and someone who notices when the generation numbers start drifting.
Cleaning, done safely
Clean panels when they are cool: early morning or evening, never in direct midday sun. Cold water on glass that has spent hours heating in the sun creates a sudden temperature differential across the pane. That is a thermal shock risk, and it can crack the glass. This is a safety instruction, not a preference, and it holds regardless of what cleaning method you use.
Use
Plain water and a soft brush or squeegee
This handles the great majority of dust and pollen soiling without risk to the glass coating or the frame seals.Avoid
Abrasives, pressure washers and harsh detergents
Abrasive materials scratch the anti-reflective coating over time. A pressure washer directed at seals or the junction box can force water past them.When
Early morning or evening only
Cool glass, no thermal shock risk, and no wasted generation from shading the array with your own equipment during peak sun.Height
Rooftop arrays are a professional job for most households
A tilted, potentially slippery surface, working at height, near live DC wiring, is not a casual weekend task. Ground-mounted and easily reached arrays are the exception.
What we will not tell you
You will find a specific soiling-loss percentage almost everywhere online, commonly “15 to 30 percent”. We do not publish that figure, and neither should anyone else with a straight face. Soiling loss depends on your local dust sources, rainfall pattern, panel tilt and how long since the last clean or rain. It is not a constant, and a number lifted from a different climate tells you nothing useful about your own roof.
The honest method is simpler and more accurate: watch your own generation data. Compare output to what you would expect for the season and the weather. A gradual decline that a good rain or a clean promptly reverses is soiling, and its size on your specific roof is whatever your own numbers say.
Self-cleaning and automated systems
Coating
Hydrophobic / anti-soiling coatings
Applied at manufacture or after, these reduce how strongly dust and water adhere to the glass, letting rain carry away more soiling on its own. They reduce cleaning frequency; they do not eliminate the need for it.Robotic
Automated dry-brush or water-jet systems
Motorised units that traverse the array on a fixed schedule, cleaning without anyone on the roof. Common on large commercial and utility installations where the labour cost of manual cleaning at scale is significant. Added upfront cost and its own maintenance.Sensor
Soiling-triggered cleaning
Some systems compare a reference cell against array output to detect soiling loss directly and trigger cleaning only when it has actually reached a threshold, rather than on a fixed calendar.
None of these replace inspection. A coating cannot tell you a connector has loosened; a robot cleaning schedule will not notice a cracked cell. Automation reduces one task on the list below. It does not remove the list.
Periodic inspection
A routine check, whether by you or a technician, should look at:
- Soiling and shading: including new growth that has started shading part of the array since installation, which cleaning cannot fix.
- Physical condition of the glass and frame: cracks, chips, corrosion, or a frame that has come loose from the mounting structure.
- Cable and connector condition: secure, undamaged, no signs of heat discolouration where connectors meet.
- Junction box condition: no cracking of the seal, no heat marks, no moisture ingress.
- Generation trend: the inverter or monitoring app’s output log, watched for a gradual decline distinct from ordinary seasonal and weather variation. This is the earliest warning most faults give (see the inverter’s app or portal).
Faults worth catching early
A single underperforming string
If one string consistently generates less than others of the same size and orientation, suspect a loose connector, a failing bypass diode, or shading unique to that string. Caught early, it is usually a simple fix.Hot spots
A localised warm patch on a panel, sometimes visible as discolouration, indicates a cell under stress, often from partial shading or a manufacturing defect. Left alone it can shorten the panel’s life. A thermal inspection is the standard way to find these before they are visible.Inverter fault codes or repeated restarts
Modern inverters log faults and most report them through an app or portal. A code that recurs, rather than a one-off, is worth investigating rather than clearing and ignoring.A generation drop that rain does not fix
If output stays low after a good clean or a rain that should have removed soiling, the cause is no longer soiling. That is the signal to book an inspection rather than wait for the next clean.
Origian's maintenance and AMC
We offer an annual maintenance contract covering scheduled cleaning and inspection. Specific plan tiers and scope are being finalised and will be published here once confirmed.
Scheduled AMC visits every 3 months; 48-hour response commitment for reported issues.
See maintenance and AMC options
For what each component in the system is and does before it needs maintaining, see how a solar system works, and for what a panel is constructed from, inside a solar panel.
Common questions
How often should solar panels be cleaned?
There is no single correct interval. It depends on your local dust, pollen, bird activity and rainfall, none of which are the same from one roof to the next. The reliable method is to watch your own generation data against expected output for the season. A steady decline that a good rain reverses is soiling, and it tells you your own cleaning interval better than a generic number could.
Can I clean solar panels myself?
For ground-level or easily reached installations, gently: plain water, a soft brush or squeegee, and no abrasive tools or harsh detergents that could scratch the glass or degrade seals. For rooftop arrays, working at height on a tilted, potentially slippery surface near live electrical equipment carries real risk, and professional cleaning is the safer choice for most households.
Is it true you should never clean panels when they are hot?
Yes, and this is not optional advice. Cool water striking glass that has been heating in direct sun for hours creates a sudden temperature differential across the pane, which risks thermal shock: cracking the glass. Clean early morning or evening, when the panels have cooled, never in the middle of a sunny day.
Do self-cleaning solar panels actually work?
Several technologies exist and their effectiveness varies by mechanism and by what is soiling the panel. Hydrophobic and anti-soiling coatings reduce how strongly dust adheres and let rain carry more of it away, but do not eliminate cleaning. Automated robotic or water-jet systems perform genuine scheduled cleaning without a person on the roof, at additional upfront and running cost. None of them replace periodic inspection.
What should a routine inspection check?
Visible soiling or shading from new growth, physical damage to glass or frame, secure and undamaged cable connectors, no discolouration or heat marks at the junction box, and, for anyone comfortable reading it, the inverter’s generation log for the kind of gradual decline that indicates a developing fault rather than routine weather variation.
Does maintenance affect my warranty?
Panel and inverter warranties are typically about manufacturing defects, not about upkeep. But improper cleaning (abrasive tools, harsh chemicals, pressure washing directly at the glass) or unauthorised interference with wiring can void a warranty claim if it caused the damage. When in doubt about a specific product, check its warranty document or ask your installer before acting.
Let generation data do the watching for you
Ask us about scheduled cleaning and inspection so a developing fault is caught in a routine visit, not by a bill that stops making sense.