Monocrystalline vs Polycrystalline Solar Panels

When it comes to Monocrystalline vs Polycrystalline solar panels, some of the key differences are:

1️⃣ Monocrystalline solar panels are significantly more efficient than polycrystalline solar panels

2️⃣ Mono solar panels come in three main types, ranging in efficiency

3️⃣ Polycrystalline Solar Panels are more affordable than monocrystalline

4️⃣ Polycrystalline PV cells are made from fused shards of silicon crystal. Monocrystalline PV cells are made of a single pure silicon crystal wafer. 

Working as a solar system installer has allowed me to gain first-hand knowledge. Over the past five years, I’ve encountered various solar panel types and learned their differences and how they perform in live systems. 

🦾 Which Are More Efficient: Monocrystalline Or Polycrystalline?

Monocrystalline cell panels are the best type of solar panels as they deliver higher efficiency and have more options for enhancing power output in terms of product choice.

Monocrystalline is ideal for use on smaller roofs where more power is required from fewer solar panels. The additional options of PERC and Bifacial solar panels further increase the possibilities for the end user.

Polycrystalline solar panels work well in moderate climates, where the home can accommodate more solar panels. 

Polycrystalline and Monocrystalline solar cell panels are the market’s most frequently used. Although they share the same semiconductor material, they are different in terms of performance due to the difference in their PV cell composition.

Read on to learn the difference between Polycrystalline and Monocrystalline solar panels and what applications suit which solar panel type the best.

⚖️ Polycrystalline Vs. Monocrystalline Solar Panels

The main difference between poly and mono solar panels is that mono panels are more efficient. Higher efficiency results in more power generated by solar panels. 

Besides providing power to run your household, excess energy generated when the home’s electricity demand is low, can be stored in batteries for later use, and the electricity can be pushed back into the grid. In addition, running off the batteries at night and receiving credits for power fed into the grid saves you money. 

Polycrystalline and monocrystalline solar panels are similar in that they use silicon crystals (Crystalline Silicon) as their semiconductor, which is the part of the solar panel that generates the electricity. This is, however, where the similarity ends.

How Solar Panels Generate Electricity 

Solar panels convert photons of sunlight into direct current (DC), which can power various items, including homes. Solar panels are usually connected in series strings, increasing the power generated to the desired level.

For home use, the solar panels are connected to an inverter which, when fitted with a regulator and battery charger, controls the power generated by the solar panels and charges batteries if equipped. The batteries store energy generated when the sun shines when no solar power is generated.

The inverter also performs the vital task of converting the DC power to alternating current (AC) to generate electricity for appliances and homes.

Solar panels contain two layers of semiconductive material (silicon crystals) arranged into solar cells. One is the N-type later (negative), and the other is the P-type layer (positive). The solar cells are interlinked to increase the power they generate. 

Solar panels generate electricity by absorbing available sunlight, which causes electrons to be knocked off their atoms in the N-type layer. The now free-floating electrons are attracted to the P-type layer that causes electrolysis and generates the direct current. 

Amazingly this happens purely through the solar cells being exposed to sunlight.

📝 Related article: How do solar panels work?

PV Cell Difference

Polycrystalline (Poly) solar panels are made from shards of silicon crystal that have been molten and formed into an ingot that fragments as it cools down. The fragments are molten in an oven and developed into silicon cubes. The cubes are then cut into photovoltaic wafers. 

The individual crystals don’t break down fully in the melting process but adhere to the neighboring crystals. The unique crystal processing process gives the polycrystalline solar panels their characteristic scale pattern.  

Monocrystalline or mono panels, as also known, are easily identifiable by their dark blue to black color. A Mono solar panel semiconductive layer is made from a single pure silicon crystal that, unlike poly panels PV cells, allows a better flow of electrons within the cells resulting in higher efficiency. 


Polycrystalline solar panels are marginally less efficient than monocrystalline solar panels. Efficiency is their ability to utilize available sunlight to generate electricity.

Poly solar panel efficiency is hampered by the fragmented composition of the photovoltaic cells, which restricts the flow of electrons due to the smaller size of the individual crystals.

Poly solar panels efficiency averages between 13% and 16%. Although lower, it allows solar panels up to 330 watts to power homes efficiently, provided sufficient solar panels are used.

Mono solar panels’ efficiency averages around 20%, with some mono panels reaching 23% efficiency, which is industry-leading. In addition, mono solar panels are offered in larger sizes (up to 700 watts) than poly panels, which makes them the obvious choice for many solar applications. 

Effects of Temperature On Mono And Poly Solar Panels

Poly solar panels are best suited for use in regions where moderate climate conditions are experienced. Excessive heating of the solar panels results in power losses due to a phenomenon called temperature coefficient.

Mono solar panels are great at extracting whatever little energy is available from sunlight, even when it is cloudy or overcast and even when it’s drizzling. Still, like poly solar panels, extreme heat negatively affects the energy production of mono solar panels but less than poly panels. 

Both poly and mono solar panels operate well in cold climates but won’t generate electricity if covered by snow or heavy cloud cover.

How Long Do They Last?

In terms of longevity, poly and mono solar panels are warranted to maintain at least 80% of their rated output for 25 years. Solar panels will last longer, but their production drops at about 1% per year, so even the best solar panels will eventually need replacement.

The solar panels don’t stop working after 25 years but slowly lose efficiency until their useful output or production drops below usable levels.  

Solar Panel Cost

Monocrystalline solar panels are more costly than polycrystalline solar panels. More so depending on the type of monocrystalline solar panel required. 

Polycrystalline solar panels are cheaper per solar panel. Still, more poly solar panels are required to generate the same power as mono solar panels of the same size, which may well negate the initial savings.  

Product Options

Polycrystalline Solar Panels

Poly solar panels are available in one primary format in various sizes up to 330-watt output. 

Mono solar panels tend to be larger, which makes them popular for use on smaller roofs where space is at a premium. 

Poly panels are an excellent choice for larger roof spaces despite using more solar panels to achieve the desired output.  

Monocrystalline Solar Panel Options

Significantly more product development has gone into further development of mono solar panels than poly solar panels.

The main reason, of course, is that the pure silicon crystal of the mono panel is far more efficient, thus setting a great base from which to build.

Monocrystalline solar panel development has led to two new types of mono solar panels that use the standard mono photovoltaic cells (PV) and other features to enhance their performance even further.

The Mono PERC and Bifacial Mono solar panels are the newest mono solar panels. See below to see what makes them unique.

Monocrystalline PERC

Passive emitter and rear cell solar panels physically look the same as a standard mono solar panel as the secret weapon sits deep inside the solar panel. PERC solar panels are fitted with a passive reflective sheet behind the N and P-type semiconductive PV cells.

This simple yet effective modification causes unabsorbed sunlight that has passed through the PV cells to reflect through the PV cells for a second time. As a result, an additional 5% more energy is produced, which would otherwise have been wasted.

PERC solar panels are thus also more efficient in low light conditions when compared to standard Mono solar panels, which makes them ideal for use in regions where daylight hours are limited, such as in winter months. 

An added benefit of the reflective layer is that more heat is deflected away from the solar panel, which aids significantly in countering the adverse effects of temperature coefficient (Losses in efficiency resulting from the solar panel heating up).   

Greater efficiency of the PERC solar panel means fewer solar panels need to be used to achieve a specific power output, resulting in less solar panels’ occupied roof space.

Monocrystalline Bifacial

Bifacial solar panels, as the name implies, have a front and a rear face. Bifacial means that the solar panel produces electricity on the front and rear of the solar panel. Bifacial solar panels work best when mounted above or around reflective surfaces. 

Ground-mounted angled frames, installations over walkways or parking lots where lots of sunlight is reflected off adjacent solar panels, cars, windows, or light-colored paving, etc., are the reason the solar panels were developed.  

Bifacial solar panels are primarily used in commercial applications but are a great option if you need to fun a large home or have a flat roof requiring an angled frame to mount the solar panels.

Some bifacial solar panel manufacturers claim a 30% increase in power generation under ideal conditions. 

Pros And Cons Of Each

Most affordableLower Efficiency
25 Year plus useable lifeRequire more roof space
Less temperature tolerant
Blended silicon crystalLimited product options
More efficientHigher priced
Single pure silicon crystal
25-year plus useable life
Less temperature sensitive

As shown in the above comparison, the main differences between poly and mono solar panels come down to price, efficiency, and the effects of temperature on the solar panels. 


Which Gives More Power, Mono or Poly Solar?

Monocrystalline solar panels generate more power than polycrystalline panels of the same size. The higher efficiency of the mono solar panels (17% to 23%), when compared to that of the poly (13% to 16%), results in mono solar panels generating more power even in low light conditions.

Should I buy Mono Or Poly Solar Panels?

The first choice is to buy mono solar panels as they offer the advantage of being available in larger sizes and have better efficiency, meaning they generate more power in all weather conditions.

However, if you’re on a tight budget, the poly solar panels will serve you well, provided you know their limitations. 

🏆 Poly Vs. Mono: Which Is The Winner?

Monocrystalline panels are the best because they offer a more comprehensive product choice. In addition, Mono’s produce more solar energy than poly panels, provide a better efficiency rate and require less roof space.  

Polycrystalline solar cells will serve you well if you live in a region with a moderate and primarily sunny climate. In addition, the savings on the solar panels may enable you to add a few more panels if additional power is needed. 

Now that we’ve described the differences between Poly and Mono solar panels, the next step is to contact your local solar system hardware supplier and installer. They’ll assess your power needs and advise you on the best option for the brand, size, and number of solar panels you’ll need.

I’m the website operator and editor here at ALTA Devices. The solar revolution is the most exciting thing to happen in a generation! I’ve written extensively on solar, electric vehicles, and the electrification of the marine industry. You can find out more on LinkedIn below: