Monofacial Solar Panels vs Bifacial Solar Panels: What Are They and Which One is Better?

Choosing between the latest technology, a bifacial solar panel, and its ancestor module, a monofacial solar panel, is hard, but it doesn’t have to be if you know what to consider when making a purchase. 

You should consider the following factors when choosing between the two types (monofacial solar panels, which have dominated the Indian residential solar market for decades, or the bifacial solar panels that are comparatively new, a lot more advanced, and much more efficient than monofacial solar panels):

• What’s your budget? 
• What’s the long-term return on investment vs the initial investment cost?
• Is your rooftop shadow-free, or does sunlight get blocked due to surrounding objects like trees and buildings?
• Is the surface of your rooftop reflective? 
• Do you live in areas where it snows?

While a monofacial solar panel can collect sunlight just from the front side, a bifacial solar panel collects sunlight from the front and back (rear side), both. Naturally, the latter is a lot more efficient but, not to forget, slightly pricier. 

So, is it worthwhile for homeowners to invest a little more in installing bifacial solar panels or should they stick with the older technology monofacial solar panels? These are the types of questions we’ve resolved in this guide by listing down the true advantages and disadvantages of both types. 

TL;DR Summary Box: Monofacial Solar Panels vs Bifacial Solar Panels – Quick Comparison

Verdict: Go for bifacial solar panels if long-term savings, efficiency, and power output matter more than initial cost of setting up a solar energy system. Opt for monofacial panels only if you have a tight budget and ample space.

Feature	Bifacial Solar Panels	Monofacial Solar Panels
Sunlight capture	Collects sunlight from both ends	Collects sunlight just from the front end
Efficiency rate	Ranges between 22-25% based on the solar cell technology	Ranges between 19-20% for monocrystalline monofacial solar panels Ranges between 16-17% for polycrystalline monofacial solar panels
Initial investment cost	Higher than monofacial solar panels	Lower than bifacial solar panels
Return on investment	Very high	Lower than the return on investment on bifacial solar panels
Performance under shadows/ snow	Exceptionally well	Poor performance
High temperature performance	Exceptionally well	Good but not better than bifacial solar panels
Longevity	Up to 40 years (varies from manufacturer to manufacturer)	25-30 years (varies from manufacturer to manufacturer)
Weight	Heavier Needs more care	Lighter Easier to mount
Installation space requirement	Requires less space since fewer panels generate desired electricity units	Requires more space since more panels are needed to reach the desired solar system capacity
Best for	Rooftop solar panel PV system for homes with reflective rooftops, limited space, and higher energy goals	Installations in wide open rooftops without shadows from surrounding objects

What Are Monofacial and Bifacial Solar Panels?

Monofacial and bifacial solar panels can both be made from technologies like PERC and TOPCon. Earlier, polycrystalline solar panels were a more popularly used type of monofacial solar panel in residential installations. However, polycrystalline technology is now obsolete. 

Let’s check out both the types and their working in detail.

What is a Monofacial Solar Panel, and How Does it Work?

A monofacial solar panel, as the name suggests, collects sunlight from one side (the front side). Most monofacial solar panels nowadays use monocrystalline cells since they are a lot purer and have a better efficiency rate as they are made from one ingot of silicon. 

The solar cells in a monofacial solar panel are packed between a glass layer in the front and a sturdy, insulated backsheet.

Here’s how a monofacial solar panel works:

• Sunlight falls on the front side of the solar panel: The front-end of the monofacial panel is packed with solar cells primarily made from silicon. The photons in the sunlight loosen the electrons in these solar cells. 
• Loose electrons start moving: The movement of free electrons generates an electric current in the form of DC (direct current) power.

Structure of a Monofacial Solar Panel

A monofacial solar panel of premium quality by solar panel manufacturers like Navitas Solar or ReNew Solar are designed to last for 25-30 years. 

These solar panels have a sturdy structure:

• Front, protective layer: This is typically made of tempered glass to ensure the solar cells underneath are shielded from weather elements such as rain, hail, wind, and snow. It’s engineered to be impact-resistant and highly transparent to allow maximum sunlight to pass through.
• The encapsulant adhesive layer: Between the front glass and the solar cells is an encapsulant layer, typically made of EVA (ethylene vinyl acetate). This layer bonds the solar cells to the front and back layers, provides electrical insulation, and protects cells from moisture, dust, and vibration.
• Solar cells stacked between the front layer and the backsheet: The solar cells in a monofacial solar panel (typically silicon-based) are arranged in a grid-like pattern and sandwiched between two encapsulant layers, one on each side, to cushion and protect them from physical and environmental damage.
• Insulated backsheet: The backsheet is usually made of polymer-based materials (like PET or PVF) and acts as an insulated, opaque rear cover. It protects the panel’s internal components from UV radiation, moisture, and mechanical damage, and prevents electrical leakage.
• Steel or aluminum frame: The frame, more commonly made of anodized aluminium, provides mechanical support and rigidity to the panel. It also helps mount the panel securely and ensures resistance to external forces like wind or snow load.

What is a Bifacial Solar Panel and How Does it Work?

Bifacial solar panels, unlike monofacial panels that collect sunlight just from the front, capture direct sunlight from the front and diffused (reflected) sunlight from the rear. 

Most bifacial solar panels these days use n-type half-cut PERC cells as they are incredibly efficient and perform exceptionally well even under cloud cover, shadows from nearby objects, and intense heat.

Here’s how bifacial solar panels work:

• Generate electricity using direct sunlight from the front: The front end of the bifacial panels generates DC power when photons from the sunlight loosen the electrons in the solar cells. 
• Generate electricity using diffused sunlight from the rear: Unlike a monofacial solar panel that has an opaque backsheet, bifacial solar panels have a transparent rear end. Sunlight passes through the transparent bifacial panels, falls to the ground, is reflected, and is absorbed by the solar cells again (this time, from the rear end). This diffused sunlight is again used to generate electricity.

Structure of a Bifacial Solar Panel

Since both ends generate electricity, the efficiency rate of bifacial solar panels is higher than the efficiency of monofacial solar panels. 

Here’s how bifacial solar panels are built:

• Front, protective layer: Similar to monofacial solar panels, bifacial panels have a tempered glass front layer that is highly transparent, UV-resistant, and impact-resistant. It allows sunlight to pass through and protects the internal components from weather and mechanical stress.
• Encapsulation layers: Two layers of encapsulant are used – one between the front glass and the solar cells, and one between the solar cells and the rear glass. These layers bond the structure together, offer cushioning, and prevent moisture ingress.
• Bifacial solar cells: These are specialized solar cells (typically n-type, like TOPCon or HIT) that are active on both sides. It means they can absorb sunlight from the front (direct sunlight) and the rear (reflected or diffused light).
• Rear side (glass or transparent backsheet): The glass-glass construction is more common in bifacial solar panels. In this configuration, the rear is also tempered glass, like the front, allowing reflected light to pass through and hit the rear face of the bifacial cells. This design adds weight but improves durability. The other configuration that’s comparatively lighter is the glass-transparent backsheet design.  
• Frame or frameless design: Bifacial panels may use a standard aluminum frame (around the edges, not across the face). A frameless design, on the other hand, helps reduce rear shading in vertical installations. Naturally, the latter is more popular.

Bifacial Solar Panel vs Monofacial Solar Panel: Advantages and Disadvantages 

On one hand, bifacial solar panels are much more efficient than monofacial solar panels. On the other hand, they are also more expensive. Yet, it’s recommended to go with bifacial solar panels in residential solar installations because of their numerous advantages over monofacial solar panels. 

Let’s first walk you through the advantages and disadvantages of both. 

What Are the Advantages and Disadvantages of Monofacial Solar Panels? 

Here’s a tabulated snapshot of the advantages and disadvantages of monofacial solar panels:

Factor	Advantages of Monofacial Solar Panels	Disadvantages of Monofacial Solar Panels
Affordability and efficiency	They are more affordable than bifacial solar panels	They’re less efficient than bifacial panels: Efficiency of monofacial panels with polycrystalline solar cells: 16-17% Efficiency of monofacial panels with monocrystalline solar cells: 19-20% Efficiency of bifacial solar panels with Mono-PERC half-cut solar cells: Up to 22.5%
Ease of Installation and space requirement	Since they’re simpler in design, it’s easier to install them	They require more installation space than bifacial solar panels, which can produce a lot more power for a solar system of similar capacity
Surface requirement and performance during cloud cover and snow	Do not require special reflective surfaces to perform at their best	Their efficiency reduces substantially under a cloud cover or when it snows They do not perform at their best if shadows from nearby objects fall on them during peak sunshine hours

What Are the Advantages and Disadvantages of Bifacial Solar Panels?

Here’s a tabulated snapshot of the advantages and disadvantages of bifacial solar panels:

Factor	Advantages of Bifacial Solar Panels	Disadvantages of Bifacial Solar Panels
Cost and efficiency	Regardless of their type, they have a higher efficiency rate because they generate electricity from both the front and rear ends: PERC (Passivated Emitted and Rear Cell): Efficiency up to ∼ 22-22.5% PERL (Passivated Emitted Rear Locally-diffused): ∼ 25% efficiency PERT (Passivated Emitted Rear Totally-Diffused) ∼ 23% efficiency HIT (Heterojunction with Intrinsic Thin-layer): efficiency of 23%	The cost of MonoPERC half-cut bifacial solar panels is ∼ Rs. 24 per watt*, which is higher than the cost of monofacial solar panels.
Space requirement and weight	You need a lot less space to install them when compared to monofacial panels, since fewer panels are needed to reach the desired solar system capacity.	Bifacial solar panels are heavier than monofacial solar panels.
Shadow/ snow performance and ease of installation	These perform exceptionally well: Under a cloud coverWhen it snows, as the ground surface becomes extremely reflective due to snowEven when shadows fall on solar panels during peak sunshine hours due to the half-cut design of solar cells	It’s slightly complicated to install them since they’re heavier than monofacial solar panels

*Please note: The aforementioned bifacial solar panel price is for DCR modules, and the rates can vary from city to city, too. These prices are just the panel prices from OEM. The actual cost of a complete solar installation is different. These rates should not be confused with the total on-grid solar system installation cost in India. Also, the prices for monofacial solar panels are based on standard market estimates, and they can vary from city to city, too. 

Which is Better, Monofacial or Bifacial Solar Panels (And Why)?

Bifacial solar panels are typically better for most homeowners due to higher efficiency, better ROI, and superior performance under shadows and snow.

And, in the solar industry, the efficiency of the panels you install always steals the top spot. Why, you ask us? That’s because higher efficiency rates mean the panels will turn out to be much more economical in the long run. You’ll get a better ROI and save a lot more money than what you invested in installing that on-grid solar on your rooftop. 

So, which of the two is better, bifacial or monofacial panels? Installing a bifacial solar panel at homes is a lot more beneficial than going with a monofacial solar panel nowadays because bifacial solar panels: 

• Generate more power, which results in better ROI as the initial investment cost breaks even sooner than monofacial solar panels.
• Last a lot longer and have a better PID (potential induced degradation), which keeps them a lot more efficient for a lot longer than monofacial solar panels.
• They have a lower current temperature coefficient (around 0.05), which keeps them performing exceptionally well even when temperatures rise exponentially. Please note that the temperature coefficient varies from manufacturer to manufacturer. 
• Perform well even under a cloud cover or shadows from nearby objects, ensuring your home remains powered even under low light weather conditions. 

Wondering just how much money installing an on-grid rooftop solar system can save you in the long run? Use this rooftop solar calculator by SolarSquare to get an idea. 

Why Choose SolarSquare as Your Solar Installation Company?

Whether you want to install commercial rooftop solar or you’re looking to install rooftop solar for housing societies and homes, SolarSquare is a trusted name. 

Here’s why over 7,000+ customers have rated us 4.8 on Google:

• You get a swift on-grid rooftop solar system installation in just 8 hours.
• We offer a minimum 45 maintenance visits over 5 years for deep cleaning and preventive checks.
• Our HILTI AirTight chemical anchoring protects your roof. And if a leak still appears, we offer a Rs. 1 lakh leakage-free guarantee for 1 year. 
• We’re the first and only solar company in India to offer a money-back guarantee at Rs. 8 per unit if we fall short on promised generation.
• Our systems are equipped with IIT-Bombay approved cyclone-proof structures, WindPro Mount™, that can withstand up to 170 km/h wind speeds. 
• Our systems use virgin-steel frames from top brands that resist rust and last 25+ years.

Please note: SolarSquare does not install off-grid solar systems and hybrid solar systems. We specifically cater to installing on-grid PV rooftop systems at commercial establishments, housing societies, and homes. 

Conclusion 

Although choosing between a monofacial solar panel vs a bifacial solar panel is a personal decision that’s influenced greatly by budget, it’s not enough to only consider how much money you will have to invest upfront. While a bifacial solar panel will cost more than a monofacial solar panel upfront, the overall value comes from years of savings. 

By that standard, a bifacial solar panel turns out to be even cheaper than a monofacial solar panel because once the investment cost will break even, bifacial panel will continue generating more power than monofacial panels ever can, which, in turn, will result in a lot more savings than an initially cheaper monofacial panel can ever provide. 

Have further doubts and questions about the cost of installing solar in India and which system size is most suited for your home, based on your electricity consumption? Book a free solar consultation with SolarSquare and let our experts solve all your queries. 

FAQs

Q1. What is the efficiency of monofacial solar panels?

Ans. Here are the efficiency rates of monofacial solar panels: Monofacial solar panels with polycrystalline solar cells: 16-17% Monofacial solar panels with monocrystalline solar cells: 19-20%

Q2. Which type of PV cell is used in monofacial solar panels?

Ans. Mostly, a monocrystalline silicon solar cell is used to make monofacial solar panels. However, many solar panel manufacturers have begun utilizing N-type and PERC cells to design monofacial solar panels, thereby increasing their efficiency rates.

Q3. Which is better, monocrystalline or polycrystalline solar panels?

Ans. A monocrystalline monofacial solar panel performs a lot better than a polycrystalline monofacial panel. In fact, polycrystalline panels are almost obsolete in India now.

Q4. Are lithium batteries good for solar systems?

Ans. Yes. Lithium batteries are not just good but mandatory for hybrid and off-grid solar systems. They last a lot longer than lead-acid batteries. However, incorporation of lithium batteries makes solar systems more expensive.