When talking to suppliers of photovoltaic solar systems, you will come across a series of vocabularies, models, brands, and prices of photovoltaic solar panels. One of the main differences between the models and the type of photovoltaic cell technology is crystalline and thin film technology. Cells are the components responsible for capturing radiation and transforming it into energy, so they are one of the main components of the photovoltaic solar panel.
Types of cell technologies: crystalline and thin films
In summary, two leading technologies dominate the world photovoltaic cell market: crystalline technology and thin film technology. The main difference between them is the material they are made of, as crystalline cells, have silicon as raw material, and dominate the market with approximately 80% of world production.
Thin film cells are formed by amorphous silicon, microcrystalline silicon, cadmium telluride, copper, indium, gallium selenide, and organic photovoltaic solar cells.
Thin film technology has undeniably relevant advantages, such as the possibility of being flexible, being aesthetically more beautiful (homogeneous appearance), and temperature and shading having less influence on it.
Despite this, it loses market share to crystalline technology, mainly because they are less efficient and require more space to install at least a 3kw solar panel system in the Philippines with the same power generation capacity.
Although the modules made of thin film, when compared in isolation, can be even cheaper than the crystalline ones, more space generates the need for more fixing structure and cabling, making the complete project more expensive than the crystalline technology. Furthermore, thin film modules’ manufacturing warranty is lower than crystalline modules.
Crystalline technology of photovoltaic modules
I will focus in this section on the technology that dominates the market. Crystalline technology can be separated into monocrystalline and polycrystalline. We will see the difference, advantages, and disadvantages between the two groups of crystals.
Difference between monocrystalline and polycrystalline cell
Both have the raw material silicon. However, the main difference is the method of manufacturing and handling silicon. Polycrystalline modules are made from many tiny silicon crystals. Thus, these various crystals are fused and give rise to large blocks, and from these blocks, photovoltaic cells are produced—a single, purer crystalline block forms monocrystalline modules.
Several tiny crystals form the polycrystalline modules. The borders between these crystals make it difficult for electric current to pass. Therefore, monocrystalline modules are more efficient when we analyze power by area, as they have more space for electrons to move and generate energy.
From the physical appearance, monocrystalline modules differ by having a homogeneous color and typically rounded corners. Therefore, they are considered more aesthetically pleasing. In contrast, polycrystalline crystals are generally bluish and not as homogeneous.
What is Monocrystalline Photovoltaic Solar Panel
Although polycrystalline silicon has historically had a larger market share, while monocrystalline silicon is an even older technology, since 2018, monocrystalline has been gaining ground. In fact, with these new technologies, it is possible to produce increasingly efficient modules. Therefore, achieving a competitive price in the market. As such, manufacturers predict that mono will increasingly dominate the market in the coming years.
Advantages Of Monocrystalline Modules
1. They have greater efficiency when compared to other commercially viable technologies.
2. They need less space to generate the same amount of energy.
3. Warranty from most manufacturers is 25 years.
4. In conditions of low light or incidence of shadows, they behave better than polycrystalline.
Disadvantages of Monocrystalline Modules
1. Monocrystalline modules are more expensive when compared to polycrystalline and some thin-film modules.
2. They generate a more significant cut of silicon from the block when producing the cells, which is discarded. So, an enormous surplus of material needs to be recycled.
What is Polycrystalline Photovoltaic Solar Panel
Polycrystalline silicon is also known technically, although less commonly, as multicrystalline. Due to its simplicity of manufacture and, consequently, lower cost, polycrystalline silicon has historically dominated the market. It has been losing a bit of space recently, but it is still one of the most used technologies due to its cost-effectiveness.
Advantages of Polycrystalline Modules
1. They tend to be cheaper compared to monocrystalline modules.
2. Commercially more viable due to strong market presence and competitive price. Although it is changing, we will see more ahead in the future.
3. Warranty from most manufacturers is 25 years.
4. They generate less waste from silicon cutting.
Disadvantages of Polycrystalline Modules
1. They are less efficient than the monocrystalline ones, mainly when we analyze generation by module area.
2. They need more space to generate the same energy as monocrystallines.
Will polycrystalline modules “disappear” from the market?
As I commented, historically, polycrystalline modules dominated the photovoltaic market for at least a decade. However, in 2018, the production of monocrystallines increased substantially, and poly began to lose preference.
Monocrystalline modules were only used by those looking for greater efficiency and not concerned about the price. As technology advances and the consequent improvement in cost-effectiveness, in 2019, they took the lead in manufacturing volume compared to polycrystalline modules.
Anyway, the trend I see is that polycrystalline modules will continue to fall—the percentage of each technology in the volume of Chinese modules exported in 2020. What used to be a dominance of polycrystalline modules is now inverted.
Lately, the export of monocrystalline manufactured in China represented about 80%, compared to other technologies. Bearing in mind that China represents around 90% of world production of photovoltaic modules, that is, it dominates the sector.
Some module manufacturers have also announced that they will abandon the manufacture of polycrystalline modules. So, based on the data and market changes, there is still a strong trend that polycrystalline modules have increasingly represented an insignificant portion of the market.
Cast-mono silicon photovoltaic solar panel
Another technology that has begun to show great results is cast-mono silicon, both in terms of efficiency and cost. Much newer than the technologies discussed above, the technique was patented in 2008.
However, this technique aimed to create a module with cheaper manufacturing than the mono, with similar efficiency. The idea was to have a module that was between a poly and a mono.
So, a cast-mono module, also known as quasi-monocrystalline, has parts of the module formed by monocrystalline crystals and parts by polycrystalline crystals.
Every technology needs maturation to take shape and thus become commercially viable. So, cast-mode entered the market recently, and one of the manufacturers that took the technology forward was the great Canadian Solar.
In the past year, Canadian Solar broke the efficiency record and announced that it achieved 22.8% efficiency in cells, called P5 technology. These cells are produced with cast-mono silicon.
Cast-mono silicon, for example, shows how the market is constantly changing. New technologies always emerge, and we always need to be aware.
Polycrystalline and monocrystalline modules: Which one to choose?
It became clear that polycrystalline silicon is losing ground in the market, giving more space to monocrystalline technology. I see this as very positive, as we discuss greater efficiency and a viable cost for the market.
I see how new technologies always emerge, so it’s essential to be aware of changes and news in the market. In this post, I focus on the differences between mono and poly, but as I mentioned, there are other technologies.
Choosing which technology to use in your photovoltaic solar plant is personal for each consumer. However, the important thing is to have trained professionals who can help you get the best cost-benefit for your project. Each project has particularities that a professional solar installer must evaluate.