Solar Panels, Types, Comparison and key things you should know
The solar panels are the most important part of any solar power system. For Indian conditions, major factors influencing our choice for a specific type of solar panels is primarily based on the few key things such as output power efficiency, demand for power, location, available space, and above all the budgetary consideration.
In present times, the world has been adopting renewable power at a rapid rate. India is also emerging in the global arena as a leading generator of renewable energy.
Our country is supposed to be one of the few countries, which is blessed with abundant solar energy due to its geographical location in the tropical region. There is a huge potential for the growth of the Indian Solar Energy sector.
It is one of the few countries to get 300-330 total clear sunny days in a year. Technically, India can produce enough solar power to meet its entire power requirements. The opportunities to grow and expand are huge since the country only taps 1% of this potential currently.
In India almost 87% of the solar power generation is from large scale industrial solar plants, but now a days the adoption rate of solar rooftop panels is accelerating at much faster rate.
The biggest advantage of installing rooftop solar panels is that they offer cost savings.
The solar panels are the most important part of any solar rooftop installation.
The next major consideration, is the type of solar panel which can give you an optimized solution for your budget and power requirement. The installation cost does play a crucial role in the decision-making process and hence our choice should be to maximize the return from the solar installation.
Although there are many types of solar panels available globally (such as Monocrystalline, Polycrystalline & Thin Film Type) , but in India, generally most of the time get the following two options while buying:
Monocrystalline solar panel – where the entire panel is made up of a single layer of uniform, pure silicon crystal bars.
Polycrystalline solar panel – where different layers of crystals are moulded together to form a single panel.
There is not much to differentiate here between mono and polycrystalline solar panels. Both are available in a wide range of output power segregated in terms of their efficiency. You can choose from a range of 50 to 400-watt solar panel options in slots of 13-17% efficiency for polycrystalline panels and 17-19% for monocrystalline panels. Your selection should depend on your net requirement.
Where you place the solar panel will determine the maximum power output that you actually get from the panel. Monocrystalline panels work best when the sunlight is direct and the place seldom receives any shade. However, if there is any significant obstruction in some form, they will act the same way as polycrystalline panels and the larger investment will be meaningless. Thus, inspect your geographic location, the area around the panel and then decide on a type.
The Ministry of New and Renewable Energy (MNRE) of India supervises the production and sale of all solar panels in the country. Irrespective of the type you choose, you must consider whether the product you are buying has the necessary certifications. For coastal regions, the Ministry requires manufacturers to undergo Salt Mist Corrosion Testing. While selecting, one should insure that these mandates, which are a mark of the panel’s quality, have been followed.
Monocrystalline solar panels
Monocrystalline solar panels are the oldest but the most developed widely used solar panels in rooftop solar panel installations today.
Monocrystalline panels gives more power output than the polycrystalline ones due to their inherent structural design. Due to greater power efficiency, Monocrystalline panels are better suitable for such installation where space economy as well as power demand is a major consideration.
Monocrystalline solar panels are also called single-crystalline silicon as they are made from growing a single crystal.
Monocrystalline solar panels, due to their even crystal framework and grid like physical structure they are the most efficient types of solar panels and they are between 18 per cent to 24 per cent power efficient.
The panels comprise of monocrystalline cells of pure silicon. These silicon monocrystalline panels appear black in sunlight.
Monocrystalline have pyramid pattern in their composition, which results in larger surface area for optimum absorption of solar energy.
The monocrystalline solar panels have fairly long life span, which may last up to 30 years.
They are capable of resisting higher temperature.
Despite having many advantages, these panels involve costly installations.
Polycrystalline Solar Panels
Polycrystalline panels have a simple manufacturing process, due to this there price is less.
Polycrystalline panels are more eco-friendly than monocrystalline panels as consumption of silicon in their manufacturing process is less.
Polycrystalline panels due to poor lower heat tolerance, have lower efficiency at higher temperatures.
Polycrystalline panels offer most budget friendly option for solar system installations.
Polycrystalline panels, just like monocrystalline panels, are made up of many solar cells (PV cells) & each PV cell contains several crystals of silicon.
The surface of polycrystalline panels has a bluish tone and surface appears like a mosaic and are square.
Thin-Film Solar Panels
Thin film solar cells are used mainly to power appliances with fewer power requirements due to its low efficiency. They are also less expensive and appear flexible which makes it very easy to mount on rooftops.
Thin film solar cells find wider application in large-scale utility and industrial solar installations because of their lower efficiency ratings.
Thin film solar panels are made by depositing a thin layer of a photovoltaic substances like Amorphous silicon (a-Si) or copper indium gallium selenide (CIGS) or cadmium telluride (CdTe) onto a solid surface, like glass. Depending upon the materials being used they forms different ‘sub types’ of thin film solar panels. During the manufacturing process, the photovoltaic substance forms a very fine layers, making them flexible, lighter and easier to install.
Thin film solar panels have incredibly low efficiency ratings which is in the range of 7–13%.