Graphene technology in panels: what is it and what are its advantages?

Graphene technology in photovoltaic panels allows the modules to have better performance, thanks to its hydrophilic and photocatalytic properties, which give the panels functions self-cleaning it's from easy decomposition of organic materials, reducing the risks caused by hot-spots.

This is the analysis of André Valvezan, sales director at ZNShine Solar. During participation in the webinar held by Canal Solar, last Tuesday (23), the specialist commented on the advantages of graphene solar panels and highlighted that they are more advantageous than conventional ones. 

Watch now!

“Glass with graphene does not retain water particles, for example. Normally, rain tends to form water bubbles on the surface of the module. When it drips, it brings dust particles, and sometimes it takes a while to evaporate, causing the board's performance to be compromised, as it will block the passage of light. Therefore, traditional panels require a higher frequency of maintenance and cleaning to provide maximum power,” explained the expert. 

Read too

How should solar panels be cleaned?

“In the case of the ZNShine modules with the graphene coating, it is as if it likes water. The moment it falls on the surface it ends up spreading more easily, that is, it finds no resistance to flow and causes greater cleaning of all the dirt that is deposited”, said Valvezan. 

Furthermore, according to the expert, graphene technology ends up reducing hot spots as they have a treatment that accelerates the oxidation and decomposition of organic waste, meaning that this material spends less time deposited on the plate. 

Other features

Below are other characteristics of graphene highlighted by the ZNShine executive during the webinar:

• It is a very thin and light material – it is one atom thick;
• Ultra resistant – (200 times that of steel) in a two-dimensional format that gives it high mechanical resistance;
• It has high thermal and electrical conductivity – its thermal conductivity is 100 times more intense than that of copper, the most used conductor in the world;
• It is waterproof – being able to prevent even helium, an extremely light gas, from passing through;
• High light transmission – 97.5% over a wide range of wavelengths from ultraviolet to infrared;
• Low Joule Effect – loses little energy in the form of heat when conducting electrons.

Graphene panels vs conventional panels

To draw a comparison, Valvezan considered the modules installed outdoors for one month. He came to the conclusion that the dust accumulation on the graphene plates was 6.28g/m² – with the same characteristics, the conventional ones accumulated 13.82g/m².

“Speaking of the influence of dust, which is the issue of generation losses due to dirt, we have a loss of 2.85% in the ZHshine panels – in the traditional panel the result was 8.52%”, he pointed out. Regarding the working temperature of the module, those with graphene reduced 1 °C on average – in conventional ones there is no reduction, commented the expert. 

“Regarding operation and maintenance: in the evaluations we carried out, the cleaning frequency is 30% lower – conventional ones do not have this advantage”, he emphasized. Finally, he highlighted that the degradation rate is 15% for panels with double glass and graphene applied in 25 years, and 19.32% for normal solar panels with single glass in 25 years.

Origin of graphene

Graphene is a two-dimensional crystal formed by bonds between carbon atoms, just like diamond and graphite. The properties of this material began to be further studied and published in 2004 by scientists Andre Geim and Konstantin Novoselov, from the University of Manchester, in England, who, for this reason, received the Nobel Prize in Physics in 2010. 

They obtained the graphene when cleaning the surface of a graphite plate, gradually wearing it into an adhesive tape. When they analyzed the graphite residues that remained on the tape under an atomic microscope, they saw that these residues maintained the hexagonal crystalline structure of graphite and that they also had a peculiar symmetrical arrangement of electrons that increased their conductivity. In graphene, electrons behave as if they had no mass.