Solar cell technology has come a long way in the last four decades. We’ve come a long way from 99% pure silicon to Perovskite solar cells. But what’s next? This article will look at the HJT cell, N-type (IBC) monocrystalline silicon, and perovskite solar cells. It may be helpful to look at these different types to better understand what each one offers.
99% Pure Silicon
The 99% purity of silicon in solar cells is derived from metallurgical silicon, which is not semiconductor grade. 99% pure silicon is obtained by purifying metallurgical silicon using several steps. The first step is mixing powdered metallurgical silicon with hot hydrochloric acid. The resulting gas contains four attachments – a silicon atom in the center, an oxygen atom at one end, and a carbon atom in the other.
High-quality silicon has a low optical absorption coefficient, allowing the absorption of sunlight while reducing the recombination of minority carriers. 99% pure silicon has a very long diffusion length of photo-generated minority carriers, which limits the recombination rate and lowers the efficiency of solar cells. This long diffusion length makes it possible to balance competing processes while improving efficiency. Generally, higher purity silicon cells have a longer lifetime and better payback.
Perovskite Solar Cells
Metal halide perovskites are light harvesters that have recently stunned the photovoltaic community. They are a step away from the silicon-based solar cells of the past. But they don’t just harvest light. They also do so very efficiently. This development has stunned the photovoltaic community, and many experts now wonder if they can replace silicon-based solar cells with these new ones.
Recent studies on perovskite solar cells suggest a promising future for improving energy-conversion efficiency, but significant challenges remain. Perovskite solar cells contain up to five layers. Each performs a different function during the electricity-generation process. But because the layers are made of other materials, they can degrade quickly due to changes in temperature and mechanical stress. If these layers are compromised, the performance of the cell plummets.
In the early 80s, researchers first developed a structure for HJT solar cells. Sanyo/Panasonic commercialized it, and by 2010, the technology had reached full technical maturity. Previously, however, this solar cell structure was still limited to small niche applications because of high production costs and high-temperature coefficients. But in recent years, a group led by the Meyer Burger Group and Prof. Christophe Ballif in Neuchatel, Switzerland, has improved this technology to a level where it is suitable for gigawatt-scale applications.
While PERC technology has remained a popular choice for many years, HJT is quickly gaining ground. Its advantages include low manufacturing costs and a high relative gain of about 10 percent over PERC. However, these advantages come at a cost. HJT solar cells technology is a long-term investment, so if you’re looking to maximize your returns on solar energy, it’s worth looking into the technology now.
III-V Solar Cells
NREL is investing in developing III-V solar cells to decrease costs and increase conversion efficiency while being suitable for both space and traditional flat plate applications. The research will address several areas, including the growth of multijunction solar cells, materials and manufacturing, tracking and concentration methods, and epitaxy. This article will discuss some ongoing projects, their benefits, and the production process. Let’s get started.
This class of semiconductors has several unique properties. They combine various materials, such as binary to quaternary compounds, and the bandgap engineering process is flexible. In addition, they tend to radiate light efficiently. These characteristics make III-V solar cells an excellent option for high-efficiency photovoltaic devices. The cost and efficiency of these solar cells are the key factors that drive their development. But, these solar cells are far from the only drawbacks.
Thin-Film Solar Cells
A thin-film solar cell is the second generation of the solar cell and is made by depositing layers of photovoltaic material on a substrate. The substrate can be glass, plastic, or metal. The thin-film solar cell has many advantages over the first-generation solar cell. This type of cell can produce power with a minimal amount of energy and is an excellent choice for solar panels. But there are some downsides as well.
One of the significant drawbacks of thin-film solar cells is the materials’ thickness. A reduction in the thickness of the material would improve efficiency and manufacturing costs. The cells would be cheaper to produce and would require less material. A new design uses an onion-like structure, with a rectangular core coated in the light-absorbing semiconductor material. Then three layers of non-absorbing, anti-reflective material cover the entire surface.