Three types of solar PV panels – what are they?
Technology wise, we can categories solar PV panels into three main different kinds.
I am not going to make any decision on your behalf as to which kind of panel is best option for you. And neither should you totally depend on the door-knocking solar salesman. If you are just starting out, there are few things you should know about solar panels. In this blog page, I will put some light into that.
So, let’s start.
Types of Solar panels
While driving in the neighborhood, if you paid close attention, you may recall that some roofs have darker kind of solar panels with a very uniform appearance and while other roofs have panels that are sky blue color with speckled look and the edges of the cells are square. What is the difference?
The difference in those two styles of panel is the kind of silicon crystal wafers used. Silicon crystal wafers? Yes, silicon wafer is the substrate material used in two out of three types of solar panels. How these wafers were cast, not only determines the panel’s outer appearance, but also the price and the efficiency of the panels. Normally a wafer goes through hundreds of steps of fabrication process where the solar cells are printed, before they become the solar panels we know that convert sunlight to electricity.
The third kind of solar panel that is also popular in the market doesn’t use silicon crystal wafers. I will start with the third kind first:
Thin-film solar panel
This type doesn’t use silicon crystal wafer for its substrate. Instead, several layers of amorphous silicon (silicon that is not in crystal form) are deposited on to a substrate such as glass during the fabrication process. This process is cheaper than fabricating solar panels from the silicon crystal wafers. Which is why thin film solar is the cheapest of the three categories.
Let’ just say, if you are a homeowner you are unlikely to go with this kind. And here’s why:
- Because thin film is super inefficient, like 30% less than the other two, you will need a lot of those panels on your roof for the same output. Even if you had plenty of roof-space, there are other reasons.
- They come with shorter warranty because they tend to degrade faster.
- They may be cheaper to buy but because you have more of them to install, soft cost of the installation can get expensive.
So who uses them? If you own plenty of cheap real estate where the cost of labor is also cheap, thin film solar can be your cheapest option to go solar. They also have a nice homogenous look, which can make it appealing.
Polycrystalline solar panel
If you are the kind of person who likes to order the most popular item from the menu when you dine out, this will be your choice. Many diners already like it, it’s reasonably priced and when you are hungry it’s a safe bet. Polycrystalline solar panels have the largest market share. They are cheaper than monocrystalline and more efficient than thin film.
- As often said, you get what you pay for. Polycrystalline gives you the most bangs for your buck.
- It is less efficient than monocrystalline and has less tolerance for heat. But it is not always desired to have the most efficient panels, especially if you have enough roof space. And unless you live in a very hot weather like Darwin or Dubai, the temperature is nothing to dread about.
- Polycrystalline panels have a slightly patchy look in them. If aesthetics is something you care about deeply, this choice may not make you happy.
Monocrystalline solar panels
If you are a chocolate lover, monocrystalline is your single bean chocolate cultivated in a specific region and specific plantation. It is pure and takes more care during manufacturing and because of that, usually more expensive. In the case of solar panels, the purity of the silicon is hard to achieve. As the name implies, monocrystalline is made out of large size “single” crystal of silicon. Casting and wafering process of single crystal is more expensive – which is why these panels are more expensive than the previous two. But the purity results in higher efficiency.
- Aesthetic: This is the uniform looking, rounded edge panels you may have seen in rooftops.
- Efficiency: These panels are more efficient in converting solar energy into solar electricity. Usually 15-20% more efficient than polycrystalline. And almost double than the thin film.
- Temperature: They handle high temperature better than others. If you live in hot climate, you should consider these panels.
- Roof-space: Because these panels are highly efficient, you won’t need as many panels. This is the main reason why monocrystalline solar panels are popular in residential roofs that have limited space.
- These panels cost the highest of the three. However, as you can see above, there are benefits as well.
Thin-film aside, both mono and poly crystalline panels are good choice for your home or small business. End of the day, your personal preferences and limitations such as roof space and how much you want to spend, will dictate what’s best for your situation.
There is one more thing to consider when shopping for solar panels. And that’s: Who makes them? Not necessarily knowing the Apple and Nike brand of solar industry. But, just how there are three kinds of technology used, there are also three tiers of solar panel manufacturers: Tier1, Tier2 and Tier3.
And again, I will start from the bottom.
Tier3 solar panel manufacturers
You should never, ever buy solar panels from Tier3 manufacturer. How do you know if it’s from Tier3? Ask the sales person and then follow up with your own homework as well. Just because, you know, sometimes people are not very trustworthy. Search the manufacturer’s name and even the local company that’s selling them in Google.
This type of solar panel manufacturers have:
- 100% manual assembly production line (not good for quality).
- $0 investment in Research and Development of the technology.
- 100% of the components are bought from other manufacturer.
- Close to 90% of global manufacturers fall in this category.
Tier2 solar panel manufacturers
This category of solar panel manufacturer is certainly better than Tier3 but not quite as good as Tier1. Should you consider tier2 panels under any circumstances? If I were buying panels for my home or small business, Tier2 wouldn’t make the cut still.
- Assembly production line is a mix of automation (robots) and human. In production, it is preferred to have the line fully automated for many reasons including quality control.
- Tier2 manufacturers don’t spend a lot in R&D. This is an important element as it shows the long-term commitment of the manufacturer to the technology and the kind of technology you can expect to find in their own product.
- There are not a lot of Tier2 companies.
Tier1 solar panel manufacturers
These types of panel manufacturers are the crème of the crop. Less than 5% of the total manufacturers in the world belong to this group. You should double confirm that the panels you are getting are from Tier1 manufacturer.
Vertically integrated company; means they manufacture every components that go in a solar panel all by themselves.
They are in the business for long term, so they invest heavily in R&D to try to stay on top.
The production line is fully automated. No human interventions.
They have been in business longer than the companies in the other two categories.
So, there you go. Now you know that there are three types of solar panels and three categories of solar panel manufacturers. For the manufacturer, stick to Tier1. For technology, decide whether you want mono or poly based on your personal choice and other limitations you may have. They both are good choices.
A table that summarizes what we discussed.
|Solar Panel technology|
|Thin film (not suitable for residential)||Polycrystalline✔||Monocrystalline✔|
|Solar Panel manufacturer|
I hope you enjoyed reading this post. If you have any questions, please don’t hesitate to contact me or leave comments below.