Solar Panel Nano Coatings [What To Know About]
Solar energy is a sustainable and cleaner alternative to other energy sources. However, solar panels are susceptible to various forms of pollution, such as dust and bird droppings, which can cause a decrease in their efficiency over time.
While cleaning your solar panels frequently is ideal for maximum efficiency, it can be challenging and time-consuming, especially for larger solar panel arrays mounted on rooftops.
Additionally, using detergents to clean them can be costly, hazardous to the environment, and potentially damaging to the solar panel framework.
Fortunately, solar panel nanocoatings offer a solution to this problem. Unlike conventional coatings, nano coatings have unique characteristics that enable them to eliminate pollen, dust, and other particles, thereby keeping the panels clean and producing solar energy efficiently.
Nanocoatings technology has significantly improved the harnessing of clean and affordable energy by increasing solar energy uptake to up to 96%, boosting the efficiency of solar panels.
With nanocoatings, you no longer have to go through the trouble of cleaning each solar panel manually, making the maintenance of your solar panels more manageable, cost-effective, and environmentally friendly.
What Is Nano Coating?
A nanocoating is a coating that is made using various materials produced at the nanoscale to achieve desired properties such as dust and water repulsion.
They create a glossy, durable barrier that protects surfaces from contaminants and environmental factors.
On solar panels, nanocoatings serve the primary purpose of preserving, protecting, and enhancing the panels' energy output.
When applied, nanocoatings bond perfectly with the panel's surface and become a part of it, resulting in a smooth finish.
Nanocoatings have been used in glasses for years to make them dust and water-repellant. Typically, their layer thickness ranges from 1-100nm, and when applied, they change the characteristics of the substrate material, such as introducing self-cleaning properties.
The coating material comes in various forms, including powders, pastes, or liquids, and upon application on a substrate, it forms a layer with protective, decorative, or other specific properties.
Nanostructured coatings offer remarkable benefits that are not present in typical coatings.
They reduce contact tension, accelerate surface drying, minimize moisture penetration, and increase hydrophobicity. The molecular force generated by nanocoatings pushes water and other particles away, resulting in a self-cleaning effect.
How Do Solar Panel Nano Coatings Work?
The process of applying nanocoating involves covering a surface with an atom-thin layer of nano-protectant.
Even smooth surfaces have tiny holes and dents that allow dirt and water to bond, creating a surface area that supports contaminants. However, nanoparticles are tiny enough to fit into these holes, remain stable, and level out the surface, making it smooth.
Nanocoatings make surfaces hydrophobic and oleophobic, meaning they repel water, oil, dirt, and other contaminants. This self-cleaning feature is inspired by the lotus flower, where dirt and dust on its leaves are wiped off when it rains, keeping the flower clean.
Scientists have studied the lotus flower and replicated its self-cleaning mechanism in the lab, leading to the invention of nano coatings for various applications, including solar panels, car mirrors, kitchen surfaces, clothes, furniture, and electronics, among others.
Applying nanocoating to a surface makes it easy to clean as contaminants do not bond to the surface but instead slip off, and wiping with a cloth is sufficient.
This technology has significantly improved the efficiency and longevity of surfaces, leading to more sustainable and cost-effective solutions.
Types of Nanocoatings
There are several types of nanocoatings which include but are not limited to:
Superhydrophobic coatings
Scientists researched superhydrophobic surfaces and created a coating that could repel most liquids.
They came up with superhydrophobic nano coating. This coating protects solar materials and equipment from contamination, corrosion, and damage by other hazardous chemicals.
Superhydrophobic nanocoatings are a perfect solution for coating solar panels due to their water-repelling features. Their fabrication was inspired by nature since water repels natural surfaces such as butterfly wings and lotus leaves.
Water rolls off superhydrophobic surfaces due to the presence of nanostructure materials on these surfaces.
Superhydrophobic coatings have anti-icing, anti-dust, antifogging, antipollution, and self-cleaning features. They can increase your solar panels' efficiency by approximately 20% to 30%.
Besides using these coatings on solar panels, they are applied on road signs, household goods, and air conditioners.
Materials used in the production of superhydrophobic coatings include but are not limited to:
- Fluoropolymer coatings
- Manganese oxide polystyrene (MnO2/PS)
- Silica nano-coating
- Precipitated calcium carbonate
- Zinc oxide polystyrene (ZnO/PS) nano-composite
Responsive nanocoatings
The advancement of technology in nanocoatings has led to the invention of responsive nanocoatings. They are “intelligent” nanocoatings that respond to environmental stimuli such as heat or light.
Some of the materials in the coating change by conferring improved or new properties either actively or passively.
Anti-corrosion nanocoatings
Corrosion protection and prevention are a necessity to increase durability and extend the life of materials. The materials developed and used in modern industries require high-quality coatings to perform better without unnecessary wear and tear.
Some manufacturers apply anti-corrosion nanocoatings on solar panels to reduce corrosion caused by harsh microbial and weather conditions.
Super hydrophilic nanocoatings
Superhydrophilic surfaces dry out quickly and don't fog up when exposed to steam or condensation. Water spreads out on surfaces with superhydrophilic nanocoatings.
You can apply the coatings on your solar panels, mirrors, shower screens, and windows. Other applications include anti-condensation air conditioners, road signs, and household goods.
Self-cleaning in surfaces with superhydrophobic nanocoatings occurs through the photocatalytic process. Organic dirt on the hydrophilic surface breaks down when exposed to light.
Anti-reflective nanocoatings
Advancement in nanotechnology has led to the invention of high-efficiency solar panel nano coatings. These coatings are anti-reflective and enable solar panels to take in more sunlight.
These technologies involve the use of nanocoatings with an intermediate refractive index.
When sunlight passes through the air with a refractive index of approximately 1, it hits the solar panels surface, whose material (often silicon) has a higher refractive index of approximately 4.
The higher the abrupt change in refractive index, the higher the reflection of sunlight. This phenomenon causes some sunlight to be reflected away, reducing the uptake.
A nanocoating with an intermediate refractive index is applied on the solar panel surface to reduce the reflection rate. Materials used to make anti-reflective nanocoatings include Carbon Nano Tube (CNT), Titanium dioxide (TiO2), and Silicon dioxide (SiO2).
Tribological nanocoatings
Tribological nanocoatings are used on surfaces of different components to reduce wear and friction.
They increase cutting speed, boost the rate of material removal, and cut the maintenance costs of tools and machines. The coating also helps minimize processing cycle times. Tribological nanocoating reduces or eliminates the need to use lubricants.
In what environments can I use solar panel nanocoatings?
Nanocoatings are more effective where the material will help reduce the impact of environmental contaminants. Nanocoatings are best applicable in areas with:
- Sand or dust
- A lot of rain
- Pollution such as oil spillage, and birds’ droppings, among others.
However, anti-reflective nanocoatings are applicable in all areas.
Ready-Made Vs. DIY Solar Panel Nano Coatings
If you want a solar panel with nanocoating, you have two main options:
- Buy a ready-made (already coated) from the manufacturer.
- Buy a third-party nano coating product.
You may be wondering, which is the best option?
The following table gives an analysis of the two options:
| Solar Panel with Nano coating | DIY Nano coating |
|---|---|
| The solar panel is more expensive, especially where the nanocoating is already impregnated by the manufacturer. | The nanocoating is often cheaper; thus, the overall cost of the solar panel and the coating may be lower. |
| The coating is fitted perfectly by the manufacturer. | You have to apply the coating on the solar panel surface. This may lead to uneven application of the coating on the surface. |
| The correct amount is applied at the processing site. The spreading is also uniform. | You may end up overdoing it, which may cause more inefficiency. On the other hand, applying too little may end up being ineffective. |
How Do You Know if Your Solar Panels Have Been Coated or Not?
Nanocoatings are very tiny that you may not see them with your naked eyes. A nanometre (nm) is 10-9 meters or one-billionth of a meter or one-thousandth of a micrometer. That's too tiny to notice with your eyes.
However, you can use other methods to check if your solar panel has nanocoating. The easiest method is reading the manufacturer's manual or product description before purchasing it. Since nanocoating technology is used as a marketing advantage, most manufacturers will indicate the technology in their manual.
However, there are cases where you may not get documented information, especially when you lose solar panel documentation. There is an easy DIY test.
- Place the solar panel on a slanted surface or support structure.
- Fetch some muddy water and pour it on the front surface of the solar panel from the top.
- Observe the behavior of the water as it flows downwards. If the water flows downwards as a single or few broad streams and leaves some mud, most likely, your solar panel doesn't have a nanocoating. However, if the water breaks down into several narrow streams and water drops as it flows downwards, leaving a clean surface, then there is a high likelihood your solar panel has a nanocoating.
Please note that there is no 100% sure way of knowing whether the solar panel has a nanocoating or not unless you apply the nanocoating or the manufacturer specifies it.
Advantages of Solar Panel Nano Coatings
Self-cleaning effect
Nano-coating self-cleaning property prevents dirt, bird depositions, and other contaminants from sticking to your solar panels. When it rains, it will wipe off the dirt.
You can also spray some water on the surface to remove the dirt if it doesn't rain often. Clean panels operate efficiently and produce the maximum amount of solar energy.
Hydrophobic effect
The hydrophobic effect refers to the ability of a surface to repel water or be water-resistant.
When a surface has a hydrophobic coating, it means that it has been treated with a special material that makes it difficult for water to stick or wet the surface.
If you live in an area that receives regular rainfall, having a hydrophobic coating on your solar panel can be beneficial.
Solar panels with hydrophobic coatings repel water more quickly and effectively than those without, which means that water droplets roll off the surface easily. As a result, solar panels can continue to function efficiently even during rainy seasons.
By repelling water, the hydrophobic coating can help to prevent water damage and reduce the accumulation of dirt, debris, or other contaminants on the surface of the solar panel.
This can help to ensure that your solar panels remain in good working condition for longer periods of time, leading to better overall performance and savings on maintenance costs.
Maintenance
Cleaning roof-mounted or pole-mounted solar panels can be dangerous since you have to climb to access the surface. Hiring a cleaning expert can also be expensive. However, if your solar panels have nanocoatings, you only need to spray some water on the panels, and the magic happens. Rainwater will also do you justice.
Improved Efficiency
Improved efficiency in solar panels refers to the ability of the solar panel to convert a higher percentage of the sunlight that hits its surface into usable electricity.
When sunlight hits a solar panel, some of it is reflected back, and some is absorbed by the solar cells.
A typical solar panel without an anti-reflective nanocoating may reflect up to one-third of the sunlight that hits its surface, resulting in a lower overall efficiency.
However, a solar panel with an anti-reflective nanocoating will reflect less sunlight and absorb more of it, leading to an increase in overall efficiency.
Anti-reflective nanocoating technology reduces the amount of reflection from the solar panel surface, which means that more sunlight is absorbed by the solar cells.
As a result, solar panels with anti-reflective nanocoating technology can produce more electricity than those without. This increased efficiency can translate into more energy savings, lower energy bills, and a reduced carbon footprint.
Moreover, the nanocoating technology can also protect the solar panels from dust, dirt, and other debris that may accumulate on the surface, further improving the efficiency and longevity of the solar panel system.
Drawbacks of Having Solar Panel Nanocoating
Despite the evident benefits of nano coatings on solar panels, they pose a few challenges, which include but are not limited to:
Reduces Transmittance
Nano coating involves applying an extra layer on the surface of the PV module. This extra layer may reduce the transmittance of sunlight. However, this layer may not create a significant reduction in the operational efficiency of the solar panel.
Please note that the efficiency created by the nanocoating is only gained when the coating helps remove the inefficiency caused by contaminants.
Lifetime expectancy
Nanotechnology is a growing field and scientists are still researching nanomaterials. The gradual degradation of polymers used in nanomaterials is still a major problem.
Unlike solar panels whose life expectancy is approximately 25 years, the durability of nanocoatings cannot be guaranteed.
Conclusion
Nanocoatings have proven to be helpful in various applications, especially in solar systems.
Solar panel nanocoatings can make the surfaces self-cleaning, reduce corrosion and reduce the reflection of sunlight. These enhancements improve the PV module's uptake of sunlight and increase its output.
If you live in areas with a lot of rain, dust, sand, or industrial pollutants, buy solar panels with nanocoatings.
If you already have a solar panel that doesn't have nanocoating, consider buying one. You can buy a nanocoating product from a local supplier or a solar system manufacturer and apply it.
