Monocrystalline vs. Polycrystalline Solar Panels

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Written by Tamara Jude + 1 other Reviewed by Roger Horowitz Updated 04/17/2024

Homeowners can choose from three main types of solar panels: monocrystalline, polycrystalline, and thin-film. Monocrystalline and polycrystalline panels are the most common for residential installations, but they each have different costs, efficiency rates, and pros and cons.

We’ve broken down the key differences between monocrystalline and polycrystalline panels so you can determine the best solar panels for your home.

Monocrystalline vs. Polycrystalline Solar Panels

Monocrystalline and polycrystalline solar panels are the two most common types of solar panels. Like all solar panels, they capture the sun’s energy and convert it into electricity. Both types use silicon, a material that’s abundant and durable.

The most significant difference between these two designs is the manufacturing process. Monocrystalline (mono) panels use a single silicon crystal, while polycrystalline (poly) panels use multiple crystals melted together. Here’s a breakdown of how each type of cell is made.

Monocrystalline

Polycrystalline

Mono panels contain monocrystalline solar cells made from a single silicon crystal. This crystal is grown in a lab and formed into a cylindrical shape called an ingot.

The silicon ingots are cut into thin discs known as silicon wafers, which then undergo a series of treatments to maximize their efficiency. The rounded edges are shaved into straight edges and chamfered corners. This nearly square, octagonal shape allows more crystalline silicon cells to fit into a solar panel, minimizing the wasted space that would exist between circular cells.

Using a single crystal improves the solar panels’ efficiency and results in a sleek black surface. However, the mono cell manufacturing process is more expensive, and the shaved pieces cannot be reused for other mono cells.

Poly solar panels also use silicon, but the manufacturing process is different. Whereas mono solar panels use a single silicon crystal, poly panels use multiple silicon fragments melted together.

To create polycrystalline cells, molten silicon material is typically poured into a square mold and cut into thin wafers once cool. The multi-crystalline process is simpler and less expensive than producing monocrystalline cells, and it creates less waste.

On the other hand, fusing the crystal fragments together creates small imperfections that hamper their efficiency compared to mono cells. These imperfections also give polycrystalline cells their distinctive speckled blue appearance.

Once the individual mono or poly solar cells are manufactured, they undergo further processing to become complete solar panels. A thin layer of conductive material, typically in the form of metal lines or “fingers,” is printed onto the front and back surfaces of the cells to collect the generated electricity. The cells are then sandwiched between protective layers of tempered glass to improve their durability.

Compare Monocrystalline vs. Polycrystalline Solar Panels

Here’s an overview of the differences between mono and poly solar panels.

Factors	Monocrystalline Panels	Polycrystalline Panels
Color	Black	Blue
Cost	More expensive	Less expensive
Efficiency rate	Over 20%	15%–17%
Life span	25–40 years	25–35 years
Temperature coefficient	Lower temperature coefficient, more efficient in heat	Higher temperature coefficient, less efficient in heat

In-Depth Comparison

Mono and poly panels both harness the sun’s power, and both are popular choices. Understanding the differences between the two will help you choose the best panels for your home.

Aesthetics

Monocrystalline solar panels are black and blend in better with most rooftops. Polycrystalline panels are blue, making them more visible on roofs. You will also need more of them to produce the same amount of energy, which translates into a larger and more obtrusive array.

Cost

Monocrystalline cells are more complicated and expensive to produce than polycrystalline cells. Mono panels can cost $1–$1.50 per watt, while poly panels fall between $0.90 and $1 per watt. However, your price will vary wildly, especially with the current oversupply on the market. These costs may not seem that different, but those pennies add up when installing a 5 kWh system. Also, the difference in efficiency means you’ll need more poly panels to power your home.

Homeowners can reduce solar panel costs by using solar incentives, credits, and rebates. The federal solar tax credit provides a tax reduction equal to 30% of your solar panel installation costs, regardless of your solar panel type. Additional solar incentives and credits are available at the state and city levels. Check the Database of State Incentives for Renewables and Efficiency (DSIRE) for more information.

Efficiency

Solar panel efficiency indicates how well your panels convert solar energy into electricity. This rating is expressed in a percentage. For example, a panel with an efficiency rating of 22% will convert 22% of the sunlight it absorbs into usable energy. Efficiency rates vary due to differences in solar cell technology. Monocrystalline panels are the most efficient solar panels due to their improved solar cell technology, with rates over 20%. Polycrystalline solar panels have lower efficiency ratings in the range of 15%–17%.

Life span

Both panels have a great life span, but mono panels last longer. Mono panels can last 30–40 years with optimal care and maintenance. Poly panels degrade a little faster and typically last 25–35 years with proper upkeep.

Many panels come with a 25-year warranty. However, the warranty period is not the same as how long solar panels last. Well-maintained solar panels will typically outlive their warranty by several years.

Temperature Coefficient

Mono and poly panels also have different temperature coefficients due to their technology. The temperature coefficient indicates how well your solar panels perform when temperatures change. Panels are tested in standard conditions of 77 degrees Fahrenheit but remain at peak efficiency between 59 degrees Fahrenheit and 95 degrees Fahrenheit.

The higher the temperature coefficient, the more the panel’s power output declines in temperatures outside this range. Polycrystalline panels have a higher temperature coefficient, meaning they experience a more significant drop in efficiency as the temperature rises. Monocrystalline panels have a lower temperature coefficient and work well in heat.

*Cost data sourced from contractor estimates used by Angi.

Are Monocrystalline or Polycrystalline Solar Panels Right for You?

Monocrystalline panels are the right choice if you want the highest power output and efficiency or if you want less noticeable solar panels. A higher efficiency rating also means you’ll need fewer panels to power your home, making mono panels a good choice for roofs with less space.

Polycrystalline panels are more affordable but have lower efficiency ratings, so you’ll need more panels to run your home. This will also require more roof space. In addition, polycrystalline panels are more noticeable on your roof due to their blue color.

Keep in mind that it takes around six to 10 years to pay off solar panels. Though monocrystalline panels are more expensive upfront, you’ll generate more energy savings and potentially shorten your payback period.

For more information about choosing the right solar panels for your home, check out this video with heating expert Richard Trethewey and Mark Trout, Group CEO of Sunworks (formerly Chief Technology Officer of Vivint Solar):

Other Types of Solar Panels

Mono and poly panels are not the only available panel types. You can also install thin-film solar panels. These are made from thin layers of photovoltaic material deposited onto a backing such as glass, plastic, or metal.

Thin-film solar panels are black, thin, and flexible, which means they offer the most inconspicuous appearance. They’re also the least expensive of the three options, but they last only 10–20 years and have low efficiency rates between 9% and 15%. These panels work best for small solar installations, such as a shed or garage.

There are three main types of thin-film solar panels to consider:

Amorphous silicon (a-Si): Though thin-film solar panels do not use silicone crystals, some do use amorphous silicon. This is the oldest and most established option. Amorphous silicon is much more flexible than crystalline silicon and cheap to produce. However, it is less efficient than other PV materials.
Cadmium Telluride (CdTe): Cadmium telluride panels are another popular option. They offer a good balance of efficiency and affordability, and they perform well in hot climates. The biggest drawback is that cadmium is a toxic heavy metal, while telluride is relatively scarce.
Copper indium gallium selenide (CIGS): Thin-film panels that use a mix of copper, indium, gallium, and selenide can achieve efficiency rates similar to polycrystalline panels. CIGS panels are also durable and work better in low light or extreme temperatures than silicon ones. However, they cost more than CdTe or a-Si panels.

It’s also worth noting that you have several options within the broader categories of mono and poly panels. One example is passivated emitter and rear cell (PERC) technology, an enhancement that boosts efficiency. PERC panels have a special layer on the back that reflect unused light back to the cell, giving it a second chance to be absorbed.

Our Conclusion

Whether monocrystalline or polycrystalline panels are better for your home depends on your roof space, budget, and personal preference. Mono panels are more efficient and require less space but cost more. Poly solar panels are less efficient and need more roof space but are more affordable.

Monocrystalline and polycrystalline solar panels are available through most solar companies. Request quotes from at least three solar companies to compare panels, services, and costs. Use the tool below to begin your search for your new mono or poly solar panels.

FAQ About Monocrystalline vs. Polycrystalline Solar Panels

Which solar panel is better: monocrystalline or polycrystalline?

Monocrystalline panels are better in quality but more expensive. These panels have higher efficiency ratings and provide more power per panel, so it takes fewer panels to run your home. Polycrystalline panels are more affordable but have lower efficiency ratings, which means you’ll need a bigger array.

Which type of solar panel is the most efficient?

Monocrystalline solar panels are generally the most efficient type available. Their single-crystal cell structure allows electrons to flow more freely, improving the energy conversion process. However, due to their high efficiency and complex manufacturing process, mono panels tend to be the most expensive solar panel option.

Which type of solar panels works better in hot climates?

Monocrystalline panels have a lower temperature coefficient, meaning they work better than poly panels in hot, dry environments. However, they’re affected by cooler temperatures.

What is the main disadvantage of monocrystalline panels?

The main disadvantage of monocrystalline panels is cost. They’re the most expensive type of solar panel due to their complex manufacturing process.

What are the advantages of polycrystalline panels?

The advantages of polycrystalline panels include lower cost and less waste.

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