The first week with the system running goes like this: app open at breakfast, app open at lunch, screenshot to the family group chat when the number looks good. We all go through it, and that's fine.
The question is what comes after. When the novelty fades, what's left are the only two real tasks a residential solar system has: reading the monitoring with judgement and cleaning when it's due. The good news is there are few of them. The realistic news: both are easy to get wrong, through excess or through neglect.
Monitoring: fifteen minutes a month, not five times a day
The inverter's app is both a marvel and a trap. The trap is turning it into a source of worry over every odd number on a cloudy Tuesday.
What's worth looking at:
- Once a month: the monthly total against the same month last year (once you have history) or against the estimate your installer gave you. This is THE valid comparison. June against June. Never June against January: winter generation is naturally lower and that comparison only frightens you for nothing.
- Now and then: whether the day's curve is bell-shaped on a clear day. Rising in the morning, peaking at midday, falling in the afternoon. A bell with an odd dip always at the same hour may be new shade. Has the neighbour's tree grown? Has an aerial gone up?
- The app's alerts: switch them on. Having the system tell you when it generates zero for a day is infinitely better than discovering it on the bill two months later. It's the most profitable five-minute configuration in the whole system.
What's worth ignoring:
- The instantaneous figure. That it's generating less than an hour ago means nothing: a cloud went past.
- A single bad day, or even a grey week. The system is judged by months and by the year.
- Comparisons with your brother-in-law's system. Different roof, different orientation, different size, different region. It isn't a race, and if it were, it wouldn't be between those two runners.
There is only one real warning sign: a sustained drop with no meteorological explanation. This month well below the same month last year with similar weather, or outright zero on sunny days. There's a whole article for that case; the summary is: first cleaning and ruling out new shade, then the phone call.
Cleaning: less than you think, better than you think
Panels get dirty: dust, soot, earth, and the ever-generous contribution of birds. Dirt blocks light, and less light is less generation. So far, the logic of cleaning. Now, the two corrections:
Rain works for free. Panels are tilted and a good downpour carries off most of the dust. In areas with regular rain they stay reasonably clean on their own. That's why the right frequency depends on your area and surroundings: near a ploughed field, a building site, a busy road, or during a long drought, the calculation changes.
Method matters more than frequency. The complete kit: water and a soft long-handled brush or mop, early morning or at dusk. Never with the panel hot in full sun: the thermal shock from cold water can damage it. Forbidden: pressure washers on frames and junction boxes, abrasive products, metal scourers, and standing on the panels. Always.
And the golden rule: your safety is worth more than 3% of generation. If your panels are on a high or steeply pitched roof, cleaning isn't an "I can manage" task: it's work at height, with real risk. Hire it out or ask us. No kWh justifies a fall.
When is it due? The calendar doesn't say, visible grime and the monitoring do: clearly dirty panels plus reduced generation on clear days. And cleaning doubles as a diagnosis: if the number recovers afterwards, mystery solved without calling anyone.
Once a year, a general look
Besides the monthly cycle and cleaning when due, once a year give the system a visual check from the ground or a window: panels secure, cables tidy where they've always been, nothing loose after that storm. Anything different from how it was left on day one (fallen cables, a misaligned panel, heat marks on the board) is a call to the installer, not a weekend project.
Your living-with-it checklist
- App alerts switched on (do it today, it's five minutes)
- Once a month: the month's total against the same month previously
- Now and then: the day's curve keeping its bell shape
- Clean when the grime is visible and the number agrees, with water, a soft brush and a cool panel
- High or steep roof: cleaning is hired, not improvised
- Once a year: general visual check
That's it. Genuinely, that's it: it's probably the appliance with the best performance-to-maintenance ratio in your home. Let it work.