SelfClean Surface - self-cleaning surface

The challenge of cleanliness in photovoltaics

The problem of dirt affects every photovoltaic installation, regardless of location. Pollen of plants, dust, soot, bird droppings - all these impurities form a layer blocking the access of sunlight to photovoltaic cells. As a result, the efficiency of the installation can drop by up to 25% per year. This is a significant difference that translates directly into higher electricity bills.

The traditional solution to this problem - regular cleaning of panels - brings with it a number of challenges. First of all, access to the roof surface is difficult and dangerous. Homeowners face a dilemma: either risk getting on the roof on their own, or hire a professional cleaning company. The latter option costs from 500 to 1000 zlotys for each cleaning, which should be done 1-2 times a year.

Moreover, even professional cleaning can cause microdamage to the surface of the panels. Standard photovoltaic glass is prone to scratches, and any damage not only worsens the aesthetics, but can also become a place for further dirt to accumulate. This is a vicious circle that leads to a gradual degradation of the entire system.

Especially problematic are dirt in hard-to-reach places - at the edges of panels or in the area of fasteners. In the case of traditional photovoltaic installations, these areas often remain uncleaned, creating an ideal place for the development of microorganisms and the accumulation of permanent dirt.

It was these challenges that led us to develop SelfClean Surface technology — a solution that radically changes the approach to keeping a solar roof clean. Instead of fighting dirt, we decided to create a surface that actively prevents them, using natural physical phenomena for this.

Self-cleaning mechanism

In nature, there is a fascinating phenomenon known as the “lotus effect”. The leaves of this plant remain immaculately clean despite growing in muddy waters. The secret lies in the microscopic structure of the leaf surface, which ensures that water does not stick to it and, flowing down, takes away any impurities with it. It was this natural mechanism that inspired us to create SelfClean Surface technology.

Our solar glass is coated with a special high gloss coating that gives it superhydrophobic properties. This means that the water does not spill over the surface, but forms into droplets that quickly flow down, collecting any debris along the way. This process is especially noticeable in the rain - just look at the roof with eTile panels to notice how drops of water “roll” on the surface, leaving behind a clean trail.

The key to the effectiveness of this technology is the special structure of the coating. At the microscopic level, the surface of the glass is covered with a network of microscopic protrusions and depressions that minimize contact between water and glass. As a result, water droplets retain an almost perfectly spherical shape and easily roll even with a slight slope of the roof. This is a radical difference compared to standard photovoltaic panels, where water melts on the surface, often leaving behind characteristic streaks and mineral deposits after drying.

If you had the opportunity to touch the surface of an eTile panel and compare it to a standard photovoltaic panel, you would immediately feel the difference. The eTile surface is extremely smooth and slippery, while traditional panels have a more matte, sticky texture. This difference is not accidental - it is the result of advanced glass processing technology that we have developed in our production facility.

Importantly, self-cleaning properties are not just a superficial addition - it is an integral feature of glass that does not disappear over time. The coating is permanently fused with glass in the production process, so it retains its properties throughout the life of the roof. Even after years of exposure to changing weather conditions, UV radiation or extreme temperatures, glass retains its water-repellent properties.

Practical benefits

The implementation of SelfClean Surface technology in eTile solar roofs brings tangible benefits to homeowners that can be seen from the first months of use. Let's take a closer look at how this innovation translates into the day-to-day operation of the installation and the owner's wallet.

First of all, the frequency of necessary cleaning procedures is significantly reduced. While standard photovoltaic installations require professional cleaning 1-2 times a year, eTile roofs with SelfClean Surface technology can work effectively for up to 2-3 years without human intervention. This translates into real savings - with an average cost of professional cleaning of 750 PLN, in 10 years of use we can save up to 15,000 PLN on maintenance alone.

Even more important is the stability of energy production. Standard photovoltaic panels lose an average of 15-25% of their efficiency over a year due to dirt. In the case of SelfClean Surface technology, this reduction is limited to only 3-5%. For installations with a capacity of 10 kWp, this means additional energy production of 1000-2000 kWh per year. At current electricity prices, this translates into additional savings of the order of PLN 1000-2000 per year.

What's more, SelfClean Surface technology extends the life of the entire installation. The absence of residual dirt means less risk of the formation of so-called hotspots - overheated places that can lead to damage to photovoltaic cells. Also, the glass surface itself, thanks to its exceptional resistance to scratches and damage, retains its properties throughout the life of the roof.

It is also worth mentioning the security aspect. By eliminating the need to regularly go to the roof for cleaning, SelfClean Surface technology significantly reduces the risk of accidents related to plant maintenance. This is especially relevant for roofs with a large slope or complex geometry.

How can you maximize the benefits of SelfClean Surface technology? The main thing is to ensure the right angle of inclination of the roof - a minimum of 15 degrees. With this slope, the water droplets have enough energy to effectively flush out contaminants. It is also worth remembering that the technology works most effectively during natural rainfall - there is no need to additionally spray the roof with water.

In conclusion, SelfClean Surface technology is not only an innovative technical solution, but above all a practical tool that allows for trouble-free use of the solar roof for many years. Combining financial savings with higher efficiency and safety of use, it is another argument in favour of eTILE integrated roof systems.

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