Traditional solar panels leave a significant source of energy unused: the light reflected from the ground, rooftops, and surrounding surfaces.
Bifacial solar panels address this by generating electricity from both their front and rear sides. But simply making the rear surface active does not guarantee higher output.
The real challenge is ensuring that enough light reaches the rear surface and that the cell can convert it efficiently without increasing manufacturing cost or reducing module life.
Recent patents show that innovators are tackling this problem from multiple directions: better solar cells, reflective surfaces, intelligent trackers, advanced materials, compact panel designs, and more durable module structures.
These inventions represent one specialized segment of the broader solar energy patent landscape, where companies are competing across photovoltaic materials, cell architectures, module designs, tracking systems, and energy-management technologies.
How Do Bifacial Solar Panels Work?
Sunlight reaching the front of the panel is converted into electricity in the same way as a conventional solar module.
At the same time, light reflected from the ground reaches the panel’s rear surface. The rear side of the photovoltaic cells absorbs this light and produces additional current.
However, rear-side irradiance is usually weaker and less uniform than front-side sunlight. Mounting structures can create shadows, low-albedo surfaces can reflect very little light, and poor rear passivation can cause electrical losses inside the cell.
The patents discussed below attempt to solve these limitations by:
- Increasing the amount of reflected light reaching the module
- Improving rear-side light conversion
- Reducing electrical recombination
- Optimizing tracker angles
- Preventing moisture and degradation
- Lowering manufacturing costs
What Is a Bifacial Solar Panel?
A bifacial solar panel is a photovoltaic module designed to absorb and convert light on both its front and rear surfaces. Collectively, bifacial solar panels differ from conventional monofacial panels because they can use light reflected from the ground, rooftops, and nearby structures to produce additional electricity.
The front surface captures direct sunlight, while the rear surface captures reflected and scattered light. The resulting energy gain depends on:
- Ground reflectivity, or albedo
- Module height and tilt
- Row spacing
- Rear-side shading
- Cell bifaciality
- Tracker position
- Weather and installation conditions
This means bifacial performance is not controlled by the module alone. The cell, mounting structure, ground surface, and tracking system must work together.
Patents Behind Bifacial Solar Panel Technology
| Patent | Industry Problem | Patented Solution | Why It Matters |
| NO349861B1 | Conventional bifacial panels are difficult to use in narrow spaces such as fences, railings, and facades. | Uses rows of photovoltaic elements with a total height of 30 cm or less while keeping both sides exposed to light. | Expands bifacial generation into compact and non-traditional installations. |
| IN202641066272A | Rear-side recombination and weak passivation reduce the expected efficiency gain of bifacial PERC cells. | Adds a rear passivation layer with laser-created contact openings and front and rear metallization grids. | Improves rear-side conversion without moving away from a manufacturable PERC structure. |
| US12453188B2 | Rear irradiance varies according to installation height, ground type, and module position. | Places a reflector parallel to rows of bifacial cells to redirect light toward the module’s underside. | Makes rear-side gain less dependent on naturally available ground reflection. |
| IN202521099457A | Perovskite cells can suffer from weak rear response and losses between material layers. | Uses a multilayer perovskite structure engineered for light absorption and charge collection from both sides. | Extends bifacial technology beyond conventional crystalline-silicon cells. |
| WO2026048755A1 | Bifacial tandem cells can experience current mismatch between their top and bottom junctions. | Designs the bottom cell to receive front and rear light while controlling the photocurrent ratio between the two cells. | Helps tandem cells gain additional rear-side energy without losing output to current mismatch. |
| IN202411094520A | Flat panels do not fully capture light reflected between the module and its mounting surface. | Places inclined bifacial strips above a primary panel with reflective surfaces directing light to their rear sides. | Adds another light-harvesting layer without completely replacing the base panel design. |
| CN122438396A | Double-glass bifacial modules can suffer from moisture ingress and potential-induced degradation. | Combines anti-reflective glass, POE encapsulation, and fine-grid cell structures. | Protects long-term output while maintaining strong front- and rear-side transmission. |
| US20250202418A1 | Conventional tracker algorithms primarily optimize front-side sunlight. | Calculates front and rear irradiance at different angles and adjusts the tracker to maximize combined output, with an optional albedo-modifying arrangement. | Turns tracking software into a source of additional bifacial energy yield. |
| IN202441068579A | Grass, soil, and concrete often reflect too little light toward the rear of the panel. | Uses white coatings, aluminium foil, or reflective films beneath bifacial modules. | Offers a relatively low-cost way to improve existing bifacial installations. |
| KR20260083471A | Selective etching for bifacial PERC cells often requires expensive vacuum systems. | Uses atmospheric-pressure plasma etching in a continuous production line. | Creates a manufacturing cost and throughput advantage rather than only a performance gain. |
What Do These Patents Reveal?
Together, the patents reveal four areas where bifacial competition is intensifying.
1. Increasing Rear-Side Light
US12453188B2, IN202441068579A, and IN202411094520Afocus on increasing the amount of light reaching the rear surface. They use three different approaches:
- An integrated reflector
- Reflective ground treatments
- Inclined photovoltaic strips
The strategic objective is the same: make rear-side irradiance an engineered input rather than an unpredictable environmental benefit. This is important because a high-bifaciality module installed over a poorly reflective surface may deliver only a limited gain.
Of these, IN202441068579A makes the boldest claim: the disclosed testing reports an output improvement of up to 25% under specific conditions, comparing white paint and reflective film against non-reflective ground. As with any single-source figure, the achievable gain will vary by baseline albedo, so this ceiling should be read as a best-case result rather than a typical one.
2. Converting Rear Light More Efficiently
IN202641066272A targets rear-side electrical losses in PERC cells. Its passivation layer and laser contact openings attempt to reduce recombination while maintaining efficient current collection.
IN202521099457A goes further by applying bifacial operation to a perovskite cell stack. The patent reports a bifaciality factor of 77% and efficiency of up to 33%. These are the patent’s own disclosed figures rather than independently validated commercial results, and they should be interpreted carefully because bifacial efficiency depends heavily on the amount of rear illumination used during testing. Still, the patent signals growing interest in using perovskites for dual-side energy generation.
3. Bringing Bifaciality to Tandem Cells
WO2026048755A1 addresses a more advanced challenge. Tandem cells contain two photovoltaic junctions that absorb different parts of the solar spectrum. Their output can be restricted when one junction generates less current than the other.
Rear illumination adds more current to the bottom cell, potentially disturbing the balance between the two junctions. The patent engineers the current relationship between the top and bottom cells so that rear-side illumination can improve output rather than create a mismatch.
This indicates that future tandem cells may be designed around expected installation conditions, including ground reflectivity and rear irradiance.
4. Making Bifacial Output More Predictable
US20250202418A1 treats tracker control as a bifacial technology. Instead of selecting an angle based only on direct front-side sunlight, the system evaluates both front and rear irradiance.
This matters because the best angle for the front surface may not produce the highest combined output. Such patents could shift part of the competitive advantage from module manufacturers to:
- Tracker companies
- Solar software providers
- Plant operators
- Energy-yield modelling companies
Why Module Durability Matters
Bifacial modules often use transparent backsheets or double-glass structures so that light can reach the rear cells. These materials must provide optical transmission while protecting the module against moisture, voltage stress, and environmental degradation.
CN122438396A combines anti-reflective glass, POE encapsulation, and modified cell interconnections to suppress moisture ingress and potential-induced degradation. The patent reflects an important commercial reality:
The value of bifaciality depends on how much additional energy the module produces over its entire operating life – not only during initial testing. A panel with strong initial rear-side output may still underperform financially if its encapsulation or electrical structure degrades quickly.
Manufacturing Innovation Could Be Equally Important
Some of the most commercially valuable bifacial patents may never produce a headline efficiency record.
KR20260083471A replaces vacuum-based selective etching with an atmospheric-pressure plasma process that can be integrated into continuous manufacturing. The potential advantages include:
- Lower equipment requirements
- Faster production
- Reduced material handling
- Continuous processing
- Easier production-line integration
In a price-sensitive solar market, reducing manufacturing cost can be as strategically important as increasing module output. A manufacturer capable of producing similar-performing cells with fewer process steps may gain an advantage even without claiming the highest laboratory efficiency.
Performance Depends on the Complete System
Claims such as “up to 25% higher output” should not automatically be applied to every bifacial installation. Actual performance depends on:
- Baseline ground reflectivity
- Rear-side irradiance
- Module elevation
- Tilt or tracker angle
- Row spacing
- Shading
- Weather
- Soiling
- Module bifaciality
- Measurement conditions
A reflective coating may produce a substantial improvement over dark soil but a smaller gain over an already reflective surface. Similarly, a tracker algorithm may perform differently across flat terrain, sloped land, agricultural fields, or snowy regions.
Therefore, technology comparisons should examine total annual energy yield rather than relying only on cell efficiency or bifaciality percentages.
How Patents Are Expanding Bifacial Solar Beyond Utility Projects
Utility-scale farms, conventional rooftops, agrivoltaics, and carports are already familiar bifacial applications. The more interesting signal in the patent record is how far bifacial design is moving beyond them.
NO349861B1’s low-profile row design – keeping total panel height at 30 cm or less while still exposing both faces to light – is built specifically for structures that were never candidates for conventional bifacial modules:
- Solar fences and railings
- Building facades
- Noise barriers
- Infrastructure-integrated installations (transportation corridors, industrial perimeters, and other space-constrained sites)
In these settings, the commercial case isn’t only the electricity generated. A bifacial fence or facade element can also replace conventional fencing, cladding, or barrier materials outright – turning a piece of infrastructure that would otherwise generate no revenue into one that does. That dual function is a distinct value proposition from utility-scale deployment, where the panel’s only job is generation.
What This Means for Solar Companies
The patent activity suggests that module manufacturers may not control the entire bifacial value pool. Different companies could build defensible positions around different parts of the system:
- Cell manufacturers can improve passivation and rear contacts.
- Module companies can develop transparent and degradation-resistant structures.
- Tracker companies can optimize combined front and rear irradiance.
- Material suppliers can develop reflective coatings and encapsulants.
- Equipment manufacturers can reduce production costs.
- EPC companies can optimize ground surfaces and array geometry.
For IP teams, this means patent searches should extend beyond photovoltaic-cell classifications. Relevant inventions may also appear in patents covering:
- Reflective materials
- Solar trackers
- Plasma processing
- Construction systems
- Glass coatings
- Encapsulation
- Energy optimization software
Conclusion
Bifacial solar panels are often described as conventional panels that generate electricity from both sides. The patents tell a more important story.
The industry is moving toward systems that actively create, control, convert, and preserve rear-side irradiance. Some patents improve the solar cell. Others redesign the mounting environment, ground surface, tracker software, manufacturing process, or module protection system.
The next competitive advantage in bifacial solar may therefore come not from producing the most efficient individual panel, but from controlling the complete system that converts reflected light into predictable lifetime energy.
Want to Explore More Bifacial Solar Patents?
This analysis is based on the ten patent records provided and does not represent the complete global patent landscape. A broader analysis can reveal recent filings, leading patent owners, active legal rights, competitor R&D directions, technology white spaces, and emerging activity in bifacial perovskite and tandem solar cells.
Fill out the form to access an updated bifacial solar patent analysis and track the latest innovation and competitor activity.
Frequently Asked Questions About Bifacial Solar Panels
What are bifacial solar panels?
Bifacial solar panels are photovoltaic modules that generate electricity from light reaching both their front and rear surfaces. The rear surface uses light reflected from the ground or nearby structures to produce additional energy.
What is a bifacial panel?
A bifacial panel is another term for a bifacial solar module. Unlike a monofacial panel, it has active photovoltaic surfaces capable of converting light from both sides.
Do bifacial solar panels work on rooftops?
They can work well on rooftops when there is sufficient space beneath the modules and the roof surface reflects light. Their rear-side advantage is limited when panels are mounted flush against dark or non-reflective roofing.
What are the pros and cons of bifacial solar panels for RVs?
Bifacial solar panels can benefit RVs when used as portable, tilted, or ground-mounted panels because reflected light can reach the rear surface. They may offer little additional output when installed flush against an RV roof, where the rear side receives limited light.
Their main advantages for RV use include additional generation under favourable conditions and better use of reflected light. Their disadvantages include potentially higher cost, added weight, and limited rear-side gain in flush-mounted installations.
Are bifacial solar panels more efficient?
They can produce more total energy than comparable monofacial panels, but the gain is installation-dependent. A bifacial panel will not provide a significant advantage if its rear side is shaded or positioned over a low-reflectivity surface.
