How Efficient Is the Thin-film Technology Used in Solar Cells?

The transition to solar energy is no longer unusual but quite an everyday process. Conscious house owners concerned about the environment are trying to use solar power plants on their roofs and on their plots. Entrepreneurs are trying to reduce the cost of electricity consumption through modern technologies.

Such popularity stimulates progress in the development of this direction, and the latest achievement in this area was the film solar panel. Technology is developing rapidly, and different materials for thin film solar panels are already used in production, they have their advantages and disadvantages, and we will talk about this further.

Thin-film Solar Cell Classifications

Before going into classification, let’s recall what thin-film solar panels are – these are solar panels that consist of different layers of material, absorb light, and produce electricity. This type of battery is also called a thin-film solar panel. The flexibility of the panel is partly due to the uniquely thin thickness of the photovoltaic cells, which is only 1 micron.

Even though thin solar panel is easier to manufacture, cheaper, and more convenient, the technology has yet to become widespread. It is used mainly for commercial purposes and the space industry, but scientists believe this technology is the future of green energy. In this context, consider what thin solar panels are.

1. Amorphous Flexible Solar Panels

Source: www.pv-magazine.com

A thin film amorphous solar panel is made from silicon. It uses non-crystalline silicon and is applied on a glass, plastic, or metal base with a layer thinner than a human hair.

The advantage of this technology is a significant reduction in the use of material, including toxic impurities. The solar panel sheet is so thin that it bends well. The disadvantage is low efficiency, especially compared to traditional batteries.

2. Thin Solar Cells CdTe (Sodium Telluride)

Source: phys.org

Flexible thin film solar panels made of this material are the most popular of all types. Due to the material of manufacture, the plates have unique properties and disadvantages. Such a battery consists of several layers of a thin photovoltaic film made of cadmium telluride.

The advantage of these thin film photovoltaic is their ability to absorb not only light with a standard wavelength and a shorter one. These rays supply the energy that is most easily converted into electricity. Another plus of this type is relatively inexpensive production and ease of installation.

But this type of battery also has a downside – cadmium toxicity. Cadmium is not harmful to humans or the environment in the form from which the thin film solar cell is made. It is very important to observe safety rules when installing stations on roofs of houses and other installation places.

3. Solar Panels CIGS (Copper-Gallium-Indium Diselenide)

Source:  www.pv-magazine.com

These slim solar panels use copper-gallium-indium diselenide as an active element between two substrate layers – plastic, glass steel, or aluminum. The ultra-thin solar panel will be rigid if the substrate is hard, and if it is soft, then the panel will be flexible.

The advantage of this type is its efficiency, which surpasses standard silicon batteries in laboratory tests. The disadvantage is the price. They cannot compete with amorphous or CdTe because of the cost of production. And these panels also contain cadmium, much smaller than in CdTe.

1. Organic Thin-Film Solar Cells

Source:  www.researchgate.net

Organic photovoltaic (OPV) is the core technology for BIPV (building-integrated photovoltaics). This technology uses organic polymers as conductors, and a deposited layer of vapor or solution conducts current.

Lightweight solar panels of this type have one feature – they come in different colors. The color depends on the type of absorber. Such panels are even transparent. This gives them a wide range of aesthetic applications for integration into structures. Another advantage is the abundance of production materials for this type of solar panel. But with all these advantages, there is one, but a very significant drawback – too low efficiency, but work on this problem continues intensively.

The difficulty of use is the relatively short service life. Silicon cells are more durable due to the resistance of molecules of inorganic origin; organic contributes to the rapid destruction of cells.

1. Paper Solar Panels

Source:  www.techexplorist.com

Paper-thin solar panels are fairly common in developing and using solar energy. The first such models appeared more than 10-12 years ago. It was a specially formulated compound applied to a thin sheet of paper, resulting in the lightest solar panel. The research was useful but impractical since the photoelectric film had unacceptably low efficiency.

Modern developments in this direction are encouraging. The newest solar technology has made it possible to create a paper product with excellent transparency and optical haze. They say that these paper-thin solar cells will revolutionize the solar energy industry.

The product is still being tested, but the results are already impressive. Applying a layer of such a layer by 10% increases the efficiency of already installed rigid silicon blocks.

1. Film Solar Panels

Separately, It is worth saying about such an innovation as PV window film. It has a lot of advantages, besides that it converts light into electricity. It absorbs heat, preventing the room from heating up, repels harmful ultraviolet radiation, and darkens the window. Solar power window film is not yet widely used, but its popularity is growing rapidly.

Having understood the main types and innovative technologies, we can talk about the methods of their manufacture.

Production Methods for Thin-film Solar Cells?

Different methods make narrow solar panels, depending on their type. Rigid solar cell panels are based on crystalline silicon, while thin and flexible panels use different kinds of material.

Solar cell films are made using the evaporative phase technique. The amorphous photoconverter uses silicon hydrogen, and its ultra-thin layer is poured onto the substrate (ceramics, plastic, glass, metal, etc.). Hydrogen in the composition increases the electrophysical characteristics, due to which amorphous silicon has conductive properties.

Such production is much simpler than the manufacture of crystalline plates. In addition, solar panel film can have controlled semiconductor properties. To do this, during production, it is necessary to select the composition of the components for the required parameters. Method of sputtering also produces CIGS solar panel sheets using electron guns and vacuum. The elements of the film are successively deposited onto the substrate and then treated with selenium vapor.

Also, solar thin-film can be applied by screen printing, and this method has found wide applications on different materials. It is also possible to use the photoconverting layer by the inkjet method.

What Do Thin-film Solar Panels Look Like?

The name thin film panels should be clear. The active layer’s thickness is thinner than a human hair, but there are several such layers, and secondly, there are other component devices. So a thin-film battery looks almost the same as a standard one.

Another feature is the ability to bend. No wonder this type of battery is called a thin-film flexible solar panel. Install them on uneven surfaces, corners, facades, and so on. Another indisputable advantage is that it allows the use of thin film photovoltaics in mobile devices and places where weight is critical and if the risk of collapse under heavy loads is a small mass.

The color of the working surface can be very different and depend on what material was used in the manufacture.

What Is the Efficiency of Solar Thin-film Cells?

Low efficiency is the main problem in using thin film PV. Except for innovative films based on wood fibers, the efficiency of these panels does not exceed 18%, which is the lower threshold for efficiency in mono and polycrystalline panels. But research in this area gives hope that thin film solar panel efficiency will soon surpass traditional ones.

In What Ways Do They Behave in Hotter Conditions?

In terms of temperature, thin-film solar cells are far superior to silicon ones, and they can tolerate even intense heat without loss of performance. Such batteries can be used in desert environments, which is already a serious bid to increase the share of green electricity in the global market. Solar panel protective film protects from excessive heat and moisture, so thin-film panels are more reliable.

How Long Do They Keep Going?

We have already mentioned that organic batteries have the shortest lifespan, while silicon batteries have the longest. Regarding service life, it will be much correct to ask not for the price but the payback of solar panels. If you look at this indicator, then thin film solar panels cost pays off in 8 years. And the life of this type of battery depends on the type. It is the longest in the amorphous type and the shortest in the organic. The average figure that thin film solar panels residential have is about ten years.

How Much Do They Cost?

Since the manufacture of these batteries, the smallest waste of materials and its small amount is currently the most inexpensive type of solar panel. And with the improvement of technology, their price will fall even more, and the payback will accelerate.

Discussing whether thin film solar technology is necessary for humanity makes no sense. This is a chance for all of us to save the planet, move away from environmentally destructive technologies and get cost-effective energy.

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