Solar panels get dirty, and when they do, they stop performing as they should. Dust, Saharan dust (calima), pollen and bird droppings form a layer that reduces the light reaching the cells and, with it, energy production. The two questions every owner ends up asking are always the same: how much does cleaning cost, and how often should it be done. Let us answer them.
Why they get dirty, and how much performance you lose
On the Costa del Sol there is one factor that makes the problem worse: calima. Airborne dust from North Africa settles on the panels and, combined with overnight dew, forms a film that is hard to remove with rain alone. Add spring pollen and bird residue to that.
The impact on production is not minor. Dirty panels can lose a significant part of their output, and where dirt has built up, that loss becomes very noticeable. Every point of efficiency lost is energy no longer produced and, in grid-connected or self-consumption installations, money slipping away.
How often to clean panels on the Costa del Sol
As a general guide, in this area a professional clean twice a year is advisable. But the real frequency depends on the setting: an installation near farmland, building works or dusty roads gets dirty faster, as do those exposed to frequent calima. Ideally, cleaning should go hand in hand with some basic production monitoring, because a drop in output with no obvious cause is usually the sign that a clean is due.
What determines the price
There is no single price, because every installation is different. The factors that weigh most are:
- The number of panels and the installed capacity.
- Accessibility: a ground-level installation does not cost the same as one on a sloped roof or at height.
- The degree of accumulated dirt.
- Frequency: a regular maintenance contract works out more cost-effective than one-off visits.
It is also worth distinguishing between a residential installation and an industrial photovoltaic one (warehouse roofs, production plants). The volume and access conditions change the approach entirely, though the principle is the same: keeping panels clean means protecting the return on the investment.
Why cleaning them yourself is not a good idea
Cleaning the panels yourself looks like a saving, but it usually proves costly. Abrasive brushes and certain products scratch the surface and shorten the life of the panel. Tap water, hard across much of the coast, leaves limescale as it dries and cuts performance again. And climbing onto a roof without the right equipment is a real risk of falling. Professional cleaning is done with deionised water, without aggressive detergents, and with specific tools that respect the panel and reach it without causing damage.
Professional maintenance and savings
A proper clean restores production immediately, extends the working life of the installation and stops dirt from baking on until it becomes hard to remove. For that reason, rather than a one-off expense, it makes sense to treat it as regular maintenance: the investment is recovered in the energy the panels produce once they are back at full performance.
Frequently asked questions
Does rain not clean solar panels?
Only partly. Rain washes away the loosest dust, but as it dries it leaves residue and limescale, and it does not remove baked-on dirt such as calima or bird residue. Relying on rain alone leaves panels below their optimal output.
What are solar panels cleaned with?
With deionised water and specific tools that do not scratch the surface, without abrasive detergents. This method leaves the panel clean and free of limescale residue, which is exactly what home cleaning with tap water fails to achieve.
How much production is recovered after cleaning?
It depends on how dirty the panels were, but recovery is usually immediate and, on very dirty panels, considerable. The improvement shows in the production recorded from the day of the clean.
Would you like to know what it would cost to clean your installation, residential or industrial? Write to us at info@limantecon.com or on WhatsApp at +34 611 75 53 46 and we will prepare a tailored quote.