Types of solar panels compared: Which are better?

Do you often spot solar panels on the roofs of residential homes, commercial buildings or lamp posts? At first glance, you may notice obvious similarities like size and the visible grid pattern. But when you look a little closer, solar panels are, in fact, different. That’s right, there are different types of solar panels, and like most products, some types of solar panels are better than others. We’ll help you recognize the quality differences among the most common types of solar panels so you know what to keep an eye out for if you’re looking to install solar.

Types of solar panels compared

First, you should know that there are two different types of solar energy. Photovoltaic (PV) and Thermal. With thermal solar, the solar panels act more as mirrors to direct sunlight to a specific location to generate heat. The more common type of solar energy is Photovoltaic (or PV), the process of converting sunlight into electricity to power homes or buildings. This is the type of solar panels you see on rooftops.

According to the journal of Energy and Environmental Science, 90% of PV solar panels are made from two main types of solar cells, either monocrystalline or polycrystalline silicon. Silicon is a highly durable chemical element that converts the energy from the Sun into electricity. Although both types of silicon solar panels are used to produce power, there are pros and cons to both.

Here is what you’ll want to know about monocrystalline and polycrystalline silicon solar panels:

Monocrystalline silicon

Monocrystalline silicon solar panels are the most common and most efficient type of solar panel. Monocrystalline silicon is made by taking a melted vat of silicon, adding a crystalline “seed” to solidify the silicon into bars, which is then cut into squares or “wafers” that make up a solar panel. This results in a high-quality crystal that’s similar to the crystals used in computer chips. The process of cutting wafers from the same bar make all of the wafers nearly identical. The term “mono” refers to the identical crystalline structures throughout the entire solar panel. This helps maintain consistency, which is what makes monocrystalline silicon solar panels so efficient.

Monocrystalline silicon panels usually have solar cells that are not perfectly square but have the corners cut off as seen in the image above. This technique of “cutting corners” actually helps the flow of energy be even more efficient. Electrons travel along the “bus bars”, which is the silver lining you see in between the solar cells/wafers. By decreasing the sharpness of the corners of each solar cell, the electrons can travel through the panel more quickly.

Besides looking at the shape of the solar cells, you should also notice the color of the solar panels. The darker the color, the more sunlight the monocrystalline solar panels will attract. Of course, more sunlight means more energy. So the darker the color, the more efficient the panel.

While monocrystalline silicon solar panels are highly efficient, the efficiency comes at a price. They’re generally the more expensive type of solar panel on the market. The good news? Solar prices have decreased in the past 10 years, making solar more affordable, even for monocrystalline solar panels. You can read more about the price of solar here.

Polycrystalline silicon

Polycrystalline silicon is similar to monocrystalline silicon but has fewer steps in its development process. The crystals used to solidify the silicon are not made at the same level of quality and are not as consistent as monocrystalline. These polycrystalline solar cells are square-cut (straight corners), tend to be a bit bluer in color, and look like they have shiny confetti inside. That blue “confetti” is the crystals used to solidify the silicon. The downside with this type of crystal is that there are imperfections or “gaps” where each of them meets or overlaps. Electrons get trapped in between the crystals, making their efficiency lower than that of monocrystalline cells. Because of this, polycrystalline silicon solar panels are often cheaper, but they can still produce sufficient amounts of power. If you are on a tighter budget, polycrystalline silicon panels are a great option.

There is also a specific subtype of both monocrystalline and polycrystalline solar panels called PERC, which stands for Passivated Emitter Rear Cell. With PERC monocrystalline or polycrystalline silicon solar panels, there is an extra layer added to reduce the number of impurities or gaps within each cell. The extra layer makes solar cells more efficient, which means more solar energy for you! So if you are looking into getting solar panels, you may want to consider asking solar companies if they provide solar panels with this extra layer.