Crystalline Solar Modules
A solar PV module basically consists of solar cells, glass, back sheet and frame. Let’s talk about these terms in a bit more detail.
There are certainly 3 types of solar panels available in the solar market:
- Monocrystalline solar panels
- Polycrystalline solar panels
- Thin-film solar panels
At the initial level of manufacturing the cell, there are different types of raw materials that are used such as mono silicon, polysilicon or amorphous silicon. The Monocrystalline and Polycrystalline solar panels have similar kinds of cells and their manufacturing process is also the same. Below are the mentioned steps involved in the production of crystalline solar panels.
Step 1: Converting Sand into silicon
The very first step involves the process of converting the sand to its useful form of silicon. Sand is the basic raw material and to the fact, solar panels are made up of silicon which is a component of natural sand. It is well known that silicon is the 2nd most available element on earth to date. Also, converting sand into silicon is an energy-intensive process but it often includes the high costs in production. Highly purified silicon is made at very high temperatures.
Step 2: Formation of Ingots
Once the silicon is collected in the form of rocks. Then these silicon is melted together at high temperatures and are formed as ingots which are shaped like cylinders. To make it look like exactly a cylinder, the furnace of a cylinder is used. The experts keep a check that during the production process, all the atoms should be perfectly aligned in a structure. For providing the silicon with a positive electrical polarity, boron is used.
Now, moving towards Monocrystalline cells, these are manufactured from a single crystal of silicon. That is the reason mono silicon has higher efficiency while converting solar energy into electricity. Thus. making the monocrystalline panels more expensive and efficient.
Then, Polysilicon cells are made up of melting the silicon crystals together. This can be recognized easily by just looking at the shattered looks on glass. This is due to the silicon crystal present in it. Once the ingot is settled down and reaches the low temperature, they are polished and ground so that it gets a flat side.
Step 3: Making the Wafers
The next step is making out the wafers. These are the thin disks that have been sliced out from the silicon ingots. A wire saw is used for cutting it into disks and it is as thin as a piece of paper. Since the silicon is very shiny due to the presence of crystals in them, they can easily reflect the sunlight. Silicon wafers are covered with an anti-reflective coat so that they can absorb the maximum sunlight.
Step 4: Solar cells formation
There are certain processes involved in converting the wafer in solar cells that will be capable of converting the solar power produced into electrical power.
The wafers work as a metal conductor and are further added to each surface which gives a grid-like matrix form. This helps and converts solar energy into electricity. The coat provided to the wafer ensures that the cell absorbs maximum sunlight and does not reflect it back.
Later, Phosphorus is diffused as in a thin layer over the whole surface of the wafers which enables the wafer to charge themselves with negative electrical orientation. Earlier boron was used to charge positive electrical current so now the combination of both boron and phosphorus will work as a positive-negative junction and helps in the proper functioning of the PV cell.
Step 5: Linking the Solar Cell to Solar Panel
Then, the solar cells are arranged together by using metal connectors so as to link the cells in a matrix-like structure. Currently, the most common size used in Australian homes is the 6.6kWh solar system.
Once the cells are arranged together, a thin layer of glass is added to its front side that faces the sun directly. Talking about the backsheet, it is made up of highly durable material that is based on polymer so as to protect the panels from water, soil, and other elements. Then the connection box is added so as to provide a connection to the PV module.
Once the frame is assembled and settled down, it will provide protection from the weather. This will help in mounting or setting up the panels in different ways as well.
A very high-quality glue is used to bind every part altogether and it should not damage the cells during any bad weather conditions.
Step 6: Testing the Modules
Once the whole set-up is done, the testing process starts in which it is observed whether the cells are performing as it was expected or not. Standard Test conditions are taken into consideration while observing the performance. All the electrical parameters are noted down so that you can find out the technical results on a paper about each panel separately. The output ratings will declare the efficiency of the system, voltage, current, and temperature fluctuations.
Apart from STC, many manufacturers use different tools to measure the cell temperature and the ratings.
Lastly, the final step is the cleaning and inspection process which states whether the system is ready to set up to homes or not.
Many researchers and solar experts are working hard to develop the solar industry. They aim to reduce the price of solar panels and increase the solar panel’s efficiency. Solar panel manufacturing industries have set up a tuff competition among themselves and are becoming more popular day by day. This often has increased the number of people who are switching to solar energy over other forms of electricity generation.