Types of Solar Cells.

The type of solar cells plays an important role in solar power system applications. Converting solar energy into electricity is one of the renewable energy applications that has many advantages when replacing conventional energy sources like coal, oil, and natural gas. R&D for solar cell fabrication and technology facilitates a significant improvement in solar cells’ performance.

In the previous article, we explain how Solar cells work as a device that converts sunlight into electrical power by the Photovoltaic phenomena. We also discussed how the solar cells’ main parameters determine the performance of the solar cells like efficiency, temperature, and irradiance.

In this article, we will explore the different types of today’s solar cells used commercially. We will explain each type’s advantages, disadvantages, and other important parameters like efficiency, cost, and environmental effects. Let’s start diving.

Types of Solar Cells

There are four main types of solar cells. These types are:

Monocrystalline.
Polycrystalline.
Thin-Film.
Emerging Technologies.
Monocrystalline Solar Cells.

1. Monocrystalline Solar Cells.

Monocrystalline solar cells are also called single-crystal silicon solar cells. It represents one of the most important, durable, and efficient types of solar cells that exist nowadays. These types of solar cells are fabricated from a single crystal of high-purity silicon.

The high purity of the monocrystalline silicon cells enables high electron mobility and high electricity generation efficiency. The monocrystalline solar cells reached a maximum efficiency rate from 17% to 22%. This high-efficiency value enables the use of lower space to reduce the same amount of electricity.

Because of monocrystalline silicon cells’ high efficiency, it is considered the best choice for limited spaces like roof-tops and residential compared to other solar cell types. Also, monocrystalline silicon cells’ lifetime normally exceeds 25 years which is considered also a long life span.

The cost per watt of monocrystalline silicon solar cells is higher than the other types of solar cells because of the advantages of the high efficiency and low space reserved for that type of solar cell. As the fabrication of the monocrystal single crystal, the high silicon waste is considered as one of the disadvantages of the monocrystalline silicon solar cells.

Monocrystalline solar cells have a special uniform shape and specific black color. The reason for that is the use of high-grade silicon. The complicated process of manufacturing and material cost of monocrystalline results in a significant increase in the cost rate per watt.

The feasibility study of the high efficiency, utilizing the low area space, durability, and long life span of monocrystalline solar cells can make it a suitable investment for electricity generation from solar energy.

Monocrystalline Solar Cells

2. Polycrystalline Solar Cells.

Polycrystalline solar cells are also called multicrystalline or polysilicon solar cells. This type of cell is widely used and makes the balance between low cost and low efficiency. From the manufacturing point of view, polycrystalline cells are made from melted silicon crystals to form multiple crystals.

This process involves composing these multiple crystals into small silicone crystals to enable the full characteristics and shape of the polycrystalline silicon cells. The maximum efficiency of the polycrystalline silicon cell types is from 15 to 18% which is lower than the efficiency of the monocrystalline type.

The reason for the low efficiency is because of the impedance to the flow of electrons through the cell because of the boundaries of the silicon grains, low cost and low price of this type of solar panel make it a good choice for large-scale projects and open areas projects to reduce the overhaul cost. Although that, a lot of R&D work is done to improve and increase its efficiency.

Another advantage of polycrystalline solar cells (besides low cost) is the decrease in silicon waste by using all the available silicon material in cell fabrication. The disadvantage of that type of cell is the low efficiency (as mentioned before). and the non-informality of that type of solar cell.

The balance between low efficiency, low cost, and long life span of polycrystalline solar cells which exceeded 25 years enables the polycrystalline type to be a significant contributor to the solar energy growing around the world.

Polycrystalline Solar Cells

3. Thin-Film Solar Cells.

The manufacturing technology of this type of solar cell is designed to deposit one or more very thin (micrometers) which is significantly thinner compared to the conventional solar panels’ silicon wafers. These thin layers are deposited on a plastic, metal, and glass substrate. The types of thin-film cells include cadmium telluride (CdTe), copper indium gallium selenide (CIGS), and amorphous silicon (a-Si),

According to the natural flexibility and the light weight of the thin-film solar cells which are key advantages of these types of solar cells, thin-film solar cells are used in a variety of applications that use the traditional solar cells. These applications include windows and roof plate building materials as well as portable technologies.

Besides the flexibility and lightweight, thin-film solar cell panels have other advantages like low cost compared to the traditional ones because they require less material. Also, it fabrication process is simple and done at low temperatures which makes it more energy-efficient. Also, the thin-film type has a good performance in high-temperature and low-light applications.

The disadvantage of thin-film solar panels is their low efficiency where its efficiency is lower than the efficiency of polycrystalline solar panels. The ongoing research and development are very promising to improve its efficiency and performance. The other disadvantages of the thin film are the high degradation rate and short life span compared to other types.

Thin-film Solar Cells

4. Emerging Technologies

The emerging technologies are new and novel promising technologies in solar cell manufacturing that offer significant advances compared to the existing technologies. These technologies have a high potential impact and a high rate of development.

These emerging technologies target is to overcome the limitations of traditional solar cells. It offers a new integration of solar power. The main important types of emerging technologies are Perovskite Solar Cells and Organic Photovoltaics as well as many other emerging technologies types.

Perovskite Solar Cells (PSC).

Perovskite solar cells are made from the same crystal structure as the mineral perovskite. Their advantages are more flexible, low-cost, and highly efficient (Laboratory efficiencies have reached over 25%). The disadvantages of that type are instability and low durability because of the high degradation rate in moisture and oxygen.

Organic Photovoltaics (OPV).

Organic solar cells use organic electronics which is a work with conductive organic polymers and small organic molecules for light absorption. Their advantages are low cost, flexibility, and lightweight while their advantages are low efficiency and short life-span.