Monocrystalline vs Polycrystalline Which Is Best?
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Homeowners who decide to go solar hear a lot of new terms from solar companies. Among the most common are descriptors of two types of solar panels — monocrystalline and polycrystalline.
These names refer to two different forms of silicon. These are the two main kinds of residential solar panels used for homes in the United States. Each garners its name from the power-generating element in solar panels’ photovoltaic (PV) cells. Before deciding to install a solar array, it’s important to understand the pros and cons of these two major solar panel types.
Monocrystalline and Polycrystalline Solar Panels: The Benefits and Drawbacks of Each
Some manufacturers form silicon into bars and cut it into wafers, creating single silicon crystals that allow electrons to flow freely through them. Panels made this way are called monocrystalline panels.
Other makers melt silicon fragments together, forming material containing many crystals. Solar panels made this way are called polycrystalline panels. While they also capture energy from the sun, they allow less freedom for electrons to move inside the crystals, generating less energy. For more in-depth information on how specific brands of each monocrystalline solar panel and polycrystalline solar panels stack up against each other, visit our “Comparing Solar Panel Efficiency” page below.
Benefits of Monocrystalline Solar Panels
Monocrystalline panels are more efficient and lend themselves to more compact designs. They are typically 16.5 percent to 23 percent efficient, or about 20 percent on average, compared with about 16 percent to 17.5 percent for polycrystalline panels, for an average of about 15 percent. Monocrystalline panels’ wattage, or energy produced per panel, is also higher at about 300 to 400 watts, compared with less than 300 watts for typical polycrystalline panels. Therefore, they don’t require as much space on a homeowner’s roof.
Manufacturing Trends Favor Monocrystalline Panels
Production of monocrystalline panels is expected to rise in the coming decade. These panels were used in 90 percent of all residential installations in 2018, the latest data available, up from 40 percent in 2016, according to the 2019 Lawrence Berkeley study.
Benefits of Polycrystalline Solar Panels
Polycrystalline panels cost about a nickel per watt less than monocrystalline models, according to research by the Lawrence Berkeley National Laboratory, saving about $300 on a typical 6-kilowatt home solar array. Homeowners can accommodate the larger space needs of polycrystalline panels by mounting solar arrays on the ground, rather than rooftops.
Ground-mount solar panels or “backyard solar panels” are another method of residential solar installation for homeowners who either do not want the panels on their rooftops or do not have space on top of their roofs for the standard rooftop installation of the array. Many homeowners lack the yard space needed. Only three percent of residential arrays are ground-mounted, according to the aforementioned Lawrence Berkeley Laboratory report.
Polycrystalline Panels May Be a Better Fit for Homes with Lower kWh (Kilowatt-hour) Usage
Yes, “may” is the operative word here. Regardless of which of the four main residential solar installation types you choose for your home, the biggest determinant of whether you’ll do fine with the poly-crystalline array is your home’s energy usage. If your home’s energy usage is below 500-kilowatt hours (kWh) per month, or, more accurately, 6,000 kWh annually, neither type of solar module would be a good fit for your home since solar will not be worth it financially (if your only rationale for installing a solar array is the savings).
However, if your home’s energy consumption is 150-200 kWh per month above the 500 kWh baseline we’ve set for energy usage minimum and your home has the space for it, a polycrystalline panel is suitable. To fully leverage the solar savings of a monocrystalline panel, learn how you can increase your usage below.
Downsides of Monocrystalline Solar Panels
The higher cost is the primary obstacle to installing monocrystalline panels. Shopping for the most reasonably priced monocrystalline options can help.
Our preferred solar panel brand is Axitec, a high-quality monocrystalline panel that delivers excellent performance at a reasonable price. Homeowners pay less for Axitec panels than premium-priced panels — $2.27 to $3.31 per watt, according to Energy Sage, an industry website that matches suppliers with solar buyers.
However, Axitec offers a 15-year equipment warranty, compared with 5-10 years for most polycrystalline brands. Its panels have high-efficiency ratings of 18.96 percent to 20.45 percent, and an unusually strong performance guarantee of 90 percent for 15 years, and 85 percent through year 25 — several points higher than most polycrystalline panels.
For homeowners with special space constraints or other needs, we also install higher-priced premium panels tailored to their homes, including monocrystalline panels manufactured in South Korea by LG. These panels also have high-efficiency ratings of 18.4 to 22 percent. They carry an industry-leading equipment warranty of 25 years and an outstanding performance guarantee of 88.4 percent for 25 years.
Downsides of Polycrystalline Solar Panels
Curb appeal can make a big difference in the sale price of a home, and many homeowners want to maximize it by choosing an attractive solar array. Most homeowners see monocrystalline panels as more pleasing aesthetically because of their sleek, uniform black color.
Polycrystalline panels are blue, with a marbled appearance some people say is an eyesore. Declining prices for solar panels have eased cost pressures that might sway consumers to choose polycrystalline modules. Prices for a typical 6-kilowatt residential solar array have fallen about 80 percent in the past 10 years, according to Solar Reviews, an industry website, while homeowners’ electric bills have risen 14 percent in the same period.
Many leading vendors of polycrystalline panels are moving into manufacturing monocrystalline products. Trina Solar Energy, a maker of polycrystalline solar panels based in China, has begun offering monocrystalline panels and extended its substandard 12-year equipment warranty on some solar panels to 25 years.