What solar panel is best? Monocrystalline vs. polycrystalline
If you’re in the market for a solar energy system, then you’re probably curious about what solar panel is best.
The major types of solar panels on the market today are either monocrystalline or polycrystalline. Each type of panel has its advantages and disadvantages, and in this blog, we’ll learn about them.
But first, let’s talk about the materials that make up solar panels.
Solar cells are the basic building blocks of a solar panel. A solar panel includes dozens of solar cells connected together. The cells are made of semi-conductive material that allows for the process of converting sunlight into electricity, which is known as the photovoltaic effect.
Semi-conductive materials are neither conductive, like copper, or insulators like rubber. They’re in between.
Almost all of the solar panels on the market today are made from silicon, a common semiconductor found in many electronics. According to the U.S. Department of Energy, silicon is the second-most abundant material on Earth behind oxygen.
“Solar cells made out of silicon currently provide a combination of high efficiency, low cost, and long lifetime,” according to the DOE.
So while it’s highly likely you’ll end up with a solar panel made from silicon cells, the method of constructing those cells may differ.
As I mentioned above, solar panels are generally split into two categories: monocrystalline and polycrystalline (also known as multicrystalline).
The key difference between the two types of panels is how the silicon is manufactured. Monocrystalline cells are made from a single silicon “ingot,” according to CNET.
“To create ingots, a rod of pure crystal silicon, called a seed crystal, is placed in molten silicon. It is then slowly pulled and rotated upward, turning into a single silicon ingot. The ingot is cut into thin wafers, whose surface is roughened so it can refract more sunshine,” CNET adds.
Polycrystalline cells come from fragments of silicon that have been melted together, according to EnergySage.
You can usually tell the difference between the two types of panels just by looking at them. Monocrystalline panels have black solar cells, while the cells in a polycrystalline panel have a blueish hue.
Compare and contrast
So why should consumers care about how solar panels are constructed?
Monocrystalline solar panels typically have better efficiency. This means they’re able to convert more of the solar energy coming from the sun into electrical energy. That also means they’re generally more expensive to make. (More on this in a second.)
That means polycrystalline panels are a bit less efficient and less expensive.
Still, most panels in use these days are the more expensive monocrystalline variety. According to the National Renewable Energy Laboratory, 88% of photovoltaic shipments in 2020 were monocrystalline panels. In fact, the NREL has stopped using polycrystalline panels in their price benchmarks.
Common wisdom suggests that monocrystalline panels are more expensive than polycrystalline ones. In the first quarter of 2019, the NREL said the “ex-factory gate price” of monocrystalline panels was 40 cents per DC watt, while polycrystalline panels clocked in at 33 cents per watt.
But when all the other costs are factored in, the installed cost of monocrystalline panels ended up being cheaper, by six cents per watt.
How does that happen? One word: efficiency.
By improving efficiency, monocrystalline panels are able to make up for a higher manufacturing costs by packing more power into the panel. In other words, more bang for your buck.
“The total system cost reductions achieved by increasing efficiency with monocrystalline modules outweighed the premium in monocrystalline module price,” the NREL report said.
According to the American Solar Energy Society, monocrystalline panels are between 15% and 20% efficient, while polycrystalline panels are between 13% and 16% efficient.
Silicon-based panels are far and away the most common type found in a solar system. But how the silicon cells are constructed will affect the panel’s efficiency and price.
The industry is shifting toward more efficient monocrystalline cells, which offer customers more bang for their buck.
Read more from Northland’s solar energy experts:
- Hiring a solar panel installer? Here are some tips
- How long do solar panels last? What consumers should know
- Rapid shutdown: How it makes solar systems safer
- Bifacial solar panels: Are two sides better than one?
- What solar panel is best? Monocrystalline vs. polycrystalline