CARE OF SOLAR PHOTOVOLTAIC PANELS

 INVISIBLE SHIELD PRO 15 

PRESERVATION, ENHANCEMENT AND "PREVENTIVE CLEANING" OF PHOTOVOLTAIC PANELS AND MIRROR COLLECTORS FOR SOLAR ENERGY

Maximising solar electricity generation requires that photovoltaic solar panels and solar collectors/concentrators are kept clean and free from the build-up and accumulation of everyday organic dirt and inorganic mineral deposits; whether on buildings or 'solar farms'.

Measuring solar efficiency:

Unfortunately, all too commonly, solar efficiency (i.e. the ability of a solar panel or mirror concentrator to convert sunlight into electricity) is measured on new, clean panels or concentrators before installation and subsequent exposure to weather and pollution. This is the maximum energy that solar units will ever provide. In other words, from the moment of installation, the efficiency of solar collection can only - and does - decline; losses often approach 35%. Only by keeping panels and concentrators relatively clean - and doing so continuously - will they deliver on the promise of producing energy from the sun.

Calculating the electricity loss from panels and concentrators - when they are covered by soil and minerals is relatively easy using the same instruments that come with each unit.

The nature of glass and plastics:

Glass is easily one of our most sophisticated materials. Its strength, insulating properties and transparency make it a suitable surface for photovoltaic panels, tubes and concentrator mirrors. Whatever the form or composition of the glass, its natural surface is hydrophilic, non-conductive and microscopically irregular. It attracts and retains moisture and water-borne contaminants on its surface; allows static electrical charges to remain on its surface, which attract dust and dirt; and allows its microscopic pores to trap a myriad of reactive chemicals, particulate matter and atmospheric debris that ultimately lead to weathering, pollution, discoloration and erosion... and subsequently to the reduced transparency needed to generate energy from sunlight.

Transparent plastics are lighter, more flexible and easier to shape because they are produced by moulding or casting. Although they are significantly hydrophobic when new, they are subject to increased scratching and loss of transparency with age and UV exposure.

The effect of weather and water on the surface of glass and plastics:

Inland rain - or rain from lakes and oceans - contains a lot of dissolved gases, carbonic acid, chlorides, sulphates, nitrates, ammonia and particulates that are chemically active. Similarly, most groundwater and ordinary municipal water - while generally safe for drinking, cooking, washing, and bathing - still contains enough salts, hard water minerals, bacteria, organic and inorganic contaminants, and water treatment chemicals to be chemically active as well.

When water from both sources is allowed to evaporate on glass and transparent plastics, it combines with common impurities to promote the formation, adherence, and accumulation of insoluble mineral deposits that reduce the penetration or concentration of sunlight and associated electricity generation. So as long as it doesn't rain distilled water, photovoltaic panels and mirror concentrators will never wash themselves!

Measures to preserve the clarity of glass and transparent plastics:

The mechanism by which water acts on glass and plastic surfaces, whether vertically or horizontally arranged, is primarily evaporation.

As the components of water evaporate, they allow the other chemically active components of water to combine with organic and inorganic contaminants, bind and settle on the surface.

By making glass surfaces more hydrophobic, i.e., more water and dirt repellent, the adhesion and accumulation of insoluble dirt is reduced and this causes the remaining residue to form infinitely smaller, finer droplets. In terms of sunlight penetration or concentration, the absence of dust and mineral coatings directly translates into a reduction in efficiency loss, i.e., improved power generation performance.

In contrast, hydrophilic surfaces actually promote the "coating" action and spread of water and dirt. While this effect is dramatic in the laboratory or during heavy rain, when the rain stops and the evaporation process continues, the resulting mineral deposits widely mask and coat the surface with layers of increasing density... and consequently loss of solar efficiency.

 Durability of water and soil repellent coatings:

Due to the very nature of everyday weather, there can be no such thing as a "permanent" water-repellent and dirt-free surface... and effective surface care may not be permanent. That's why Unelko's high performance, invisible water and dirt repellent coatings are specially formulated to be compatible with all types of glass and plastics and contain ingredients important for their surface cleaning properties, providing performance guaranteed for up to 15 years (for IS Pro 15). The ultra-thin but amazingly durable nano-coatings are not affected by washing with any soap, solvent or detergent.

However, as with unprotected glass and plastics, the effectiveness of Unelko's protective coatings is gradually reduced by mechanical abrasion from wind, dirt, sand and pollutants sprayed onto solar panels and solar concentrating arrays during inclement weather.

In the real world, therefore, effective water repellent coatings must first and foremost be "renewable" by the end users of the surfaces to which they are applied for cleaning and protection. Thus, the nano-protection layer can be easily restored at any time by recoating.

"Easily cleanable" surfaces save time, repairs, replacements... and loss of efficiency.

Thanks to its unique features and performance advantages, Unelko's surface care technologies can transform conventional PV panels and mirror concentrators into "easy-to-clean" units with water, dirt and stain repellent surfaces that significantly reduce the formation, adhesion and deposition of organic and inorganic dirt and hard water mineral deposits from rain evaporation and spray from lakes and oceans.

When used as directed, Unelko's advanced surface care products literally cut cleaning time in half... while keeping surfaces shining like new.

OVERALL SOLAR CARE

1ST STEP - PREPARATION:

Removing mineral deposits and soil build-up from solar panels - safely and efficiently, without scratching or damaging the surface.

SOLUTION: Unelko's special products -Lime Scale Remover, GlassScrub, or traditional grease and soil removers, i.e. easily available, inexpensive and safe dishwashing detergents that are miscible with water and can be easily sprayed onto solar surfaces to dissolve dirt. Depending on the volume and adhesion of the surface dirt, spreading and cleaning with a soft brush may be recommended.

NOTE: Rinse thoroughly before applying durable hydrophobic surface protection to remove even residual cleaner.

2ND STEP - APPLICATIONS:

Ensure solar panels and mirror solar concentrators repel water, dirt and stains.

SOLUTION: Apply Invisible Shield, Invisible Shield PRO15 or Solar Shield to the surface to create a durable barrier that repels water, dirt and stains and is chemically impermeable. Easy to apply by hand or spray, these durable protective surface coatings require no down time. They bond instantly on contact and are immediately functional.

NOTE: The only threat to the durability of Unelko surface protection technologies is abrasion, which is not a common threat to solar panels. Harsh abrasive cleaners or tools should never be used on the surface of solar panels.

3RD STEP - MAINTENANCE:

Option to provide "permanent" protection for the solar panels with Invisible Shield, Invisible Shield PRO15 or Solar Shield water, dirt and stain repellent coatings.

SOLUTION: In the case of a product with a shield that is part of a system, it is possible to use Unelko's Repel™ Glass Cleaner, a special ready-to-use, dual-action cleaner that cleans and automatically/simultaneously "restores" barrier coatings that repel water, dirt and stains.

NOTE: By using REPEL's "dual action" technology to clean and maintain Unelko's barrier coatings, you can literally ensure a lifetime of protection because you are literally renewing the protection with every cleaning!

Do you need advice on choosing the right NANO protection? Call us at +420 734 756 669 or email us at m.valasek@gds.cz

The article was written by:

Martin Valášek

Flat glass, Paints, UV adhesives, Technical support,
Customer service, Blasting systems