How often should you have solar panels cleaned in Hungary?
SkyTech Clean · Solar panel cleaning
One of the most common questions we receive from solar farm operators and asset managers: how often does a solar system really need to be cleaned? The short answer in Hungary is typically once a year — but more important is when and why it is justified to deviate from that.
Why is one cleaning a year the baseline?
In the local climate, soiling on solar panels (dust, pollen, atmospheric deposition) accumulates slowly but continuously. Over a year this build-up can already cause a measurable 5–20% performance loss — this is the point where the cost of a cleaning almost always pays back through the additional output.
When is earlier cleaning justified?
- Near farmland — dust from fields settles faster than in urban environments.
- After a heavy pollen season (typically April–May) — pollen forms a thin but even layer that measurably reduces light transmission.
- In case of bird droppings — this is not just an aesthetic problem: the shadow spot that forms can cause hot spots, which significantly reduce panel performance locally and in the long term can even damage the panel.
- Near industrial areas or busy roads — soot and fine-dust deposits here are more persistent and harder to wash off with natural rainfall.
How do we calculate whether it is worth it?
The rule is simple: cleaning is worthwhile if the additional revenue from the expected yield increase exceeds the cost of cleaning. In practice this means that a cleaning can pay off even at a 1.5–2% yield increase, while many plants see a 10–25% increase depending on the degree of soiling.
That is why we start every project with a free on-site assessment: we measure the current level of soiling and use it to give a concrete, numerical yield forecast — we do not recommend cleaning if it does not pay off.
What can you do if you are unsure?
If you are not sure whether your solar system needs cleaning, the simplest approach is to compare current production data with the system's rated output, or with data from an earlier period after cleaning. If there is a significant, lasting deviation, it is worth requesting an assessment.