Solar panels are made of photovoltaic cells commonly known as solar cells to capture the sun’s radiation and convert it into electricity. Silicon is mainly used to manufacture solar cells. The solar cells can either be monocrystalline or polycrystalline in makeup. Thus, a solar panel can be a monocrystalline solar panel or polycrystalline solar panel depending upon the type of solar cells used in it. Monocrystalline solar cells have higher efficiency and are widely used to make solar panels.
Method of manufacturing
A monocrystalline solar cell is made of a single silicon crystal. The efficiency of monocrystalline solar cell is 20% more than other types of silicon cells. The method of manufacturing is complicated because a highly pure single crystal of silicon is required.
In the initial process, silicon dioxide is placed in an electric arc furnace. Molten silicon is produced along with carbon dioxide by heat. The silicon obtained has 1% impurity. In the next process, a rod of impure silicon is made pure by passing it through a heated zone many times. The rod becomes pure because the impurities are pushed towards one end which is removed to obtain pure silicon. Single crystal silicon required to make monocrystalline solar cell is made by Czochralski method. In this method, a silicon seed crystal is dipped in molten polycrystalline silicon in Czochralski growth apparatus. Boron is also added to impart positive charge to silicon. The seed crystal is rotated as it is withdrawn to form a cylindrical ingot of pure silicon.
Cylindrical ingot of pure silicon is then sliced into thin disks which are called wafers. An anti-reflective coating is put on the wafer to reduce reflectivity. The wafers are then heated in a furnace at a temperature below its melting point in the presence of phosphorus gas. As a result, phosphorus is doped into the silicon. Positive-negative junction is created due to presence of phosphorus and boron. Metal conductors are added on the surface to collect electricity.
The monocrystalline silicon solar cells are characterised by bluish or black colouring.
Advantages of monocrystalline solar panels
Very high efficiency is the major advantage of monocrystalline silicon solar panels. The single crystal structure of monocrystalline solar cells provides more room for the electrons to move, thereby generating more electricity. Thus, monocrystalline solar panels are suitable for generating maximum electricity in places where space is limited.
Longevity of monocrystalline panels is about 30 years or more. High longevity is due to the fact that such panels do not undergo much solar degradation and are also resistant against environmental elements. Most of the manufacturers offer 25 years warranty on their monocrystalline solar panels.
Monocrystalline solar panels give better output under low lighting conditions as compared to polycrystalline solar panels.
High temperatures lead to a drop in electricity production in solar panels. In case of monocrystalline solar panels, the loss in efficiency is not significant because the solar cells are made of pure silicon which can handle high temperature better than polycrystalline solar cells.
Installation is simple and costs less.
Prices of monocrystalline solar panels
The monocrystalline solar panel price in india is approximately Rs 60/watt. Thus, a 100 watt monocrystalline solar panel can cost Rs 6000. Other factors such as efficiency and brand also influence the price.
For example, a branded variety of 250w monocrystalline solar panel with a voltage rating of 220-240 volts can cost over Rs 13,000. Another example can be of 300 watt monocrystalline solar panel which costs about Rs 20,000.
Monocrystalline solar panels are more expensive as compared to polycrystalline solar panels. The monocrystalline solar panel price for same kind of panel can vary from one manufacturer to another.
Top brands in India
The best monocrystalline solar panels exhibiting high efficiency and long lifespan are manufactured by the top companies engaged in solar energy production.
The top rung brands of monocrystalline solar panel india include Vikram Solar, Adani Solar, Tata Power, Waaree Energies, Luminous, Sukam and Indo Solar to name a few. Imported brands of solar panels cost more than the domestic brands. The best brands have created a niche for themselves in the solar energy market in India and these brands remain high on the minds of the customers when they want to buy monocrystalline solar panels.