Assessing the Impact of Bifacial Photovoltaic Modules on Energy Efficiency

Shanika Wickramasinghe
6 min readMay 26, 2023

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With an urgent global need for renewable energy sources, new innovations like bifacial photovoltaic modules have made their way into the forefront of the solar energy field. This guide will dig deep into the benefits and implications of using bifacial PV modules for energy efficiency.

Bifacial Photovoltaic Modules: A Comprehensive Understanding

Defining Bifacial Photovoltaic Modules

Bifacial PV modules mark a significant departure from traditional solar modules. Equipped with the capacity to generate power from both sides, they offer an enhanced capability to harness solar radiation.

Working Principle of Bifacial Photovoltaic Modules

By employing cells that are active on both sides, these modules can absorb light from multiple angles. This unique feature, aided by highly reflective surroundings, enables them to capture more solar energy than their traditional counterparts.

Enhanced Energy Efficiency with Bifacial Modules

A Leap in Energy Output

Bifacial PV modules offer remarkable improvements in energy output, thanks to their ability to capture and convert additional solar radiation. Depending on their environment, bifacial modules can generate up to 30% more energy than monofacial ones.

The Power of Albedo

Albedo, or surface reflectivity, plays a significant role in bifacial modules’ efficiency. A surface with a high albedo, such as white gravel or snow, can drastically enhance the performance of these modules by reflecting more light onto their rear side.

Key Factors Influencing the Efficiency of Bifacial PV Modules

Importance of Installation Parameters

Height of Installation

The height at which bifacial modules are installed plays a critical role in their energy yield. A greater height allows more reflected sunlight to reach the rear side of the panel, thereby increasing its output. However, the optimal height may vary based on factors like local climate and ground reflectance.

Tilt Angle

The tilt angle of the module is another key parameter. Depending on the latitude of the location, different tilt angles can maximize the incident sunlight on the module, optimizing power output. Software tools are commonly used to determine the ideal tilt angle for a given location and time of year.

Ground Cover: A Critical Consideration

Role of Ground Albedo

The ground albedo, or reflectivity, greatly impacts the performance of bifacial modules. Higher albedo surfaces reflect more sunlight onto the rear side of the module, thereby enhancing power generation. Natural surfaces, such as grass or soil, typically have lower albedo compared to artificial surfaces like white gravel or concrete.

Selection of Ground Cover

When selecting ground cover for a bifacial PV installation, considerations include not just reflectance but also cost, durability, and environmental impact. For instance, white gravel may have a high albedo, but it may not be feasible or eco-friendly to implement on a large scale.

Maintaining Ground Reflectance

The maintenance of ground cover also matters. For example, grass under the PV installation needs regular trimming to maintain its reflectance properties. On the other hand, concrete or white gravel might require cleaning to prevent dirt from reducing its reflectance.

Assessing Bifacial Modules in Comparison to Monofacial PV Modules

Efficiency and Power Output

Bifacial PV modules stand out due to their potential for higher output. While monofacial modules capture light from one side, bifacial modules harness light from both sides, leading to increased energy yield.

Cost-effectiveness and Installation Considerations

While bifacial modules come with a higher initial cost compared to monofacial modules, their higher energy yield often leads to a more favorable return on investment. The installation of bifacial modules also necessitates careful planning concerning module mounting height, orientation, and ground surface.

Delving Into the Technology Behind Bifacial Modules

Material Composition and Structure

Bifacial modules are usually made from either n-type or p-type silicon cells, which offer high efficiency and long-term performance. The cells’ dual-sided structure allows them to effectively absorb light on both sides.

Evolution of Bifacial Technology

The progression of bifacial technology, from its conceptual stage to current high-efficiency models, reflects significant strides in solar technology. The continuous development aims to further improve performance and reduce costs.

Case Studies: Bifacial Modules in Action

Case Study 1: Bifacial PV Modules in High-Reflection Environment

Our first case study takes us to a solar farm in Switzerland where bifacial PV modules were installed over a highly reflective surface covered with white gravel. The additional reflected sunlight increased energy yield by 25% compared to traditional mono-facial modules. This implementation affirmed the significant role of ground albedo in the performance of bifacial modules.

Case Study 2: Bifacial PV Modules in Urban Setting

The second case study focuses on an urban setup, where a commercial building in California equipped its rooftop with bifacial modules. Despite the lack of natural high-albedo surfaces, artificial solutions like white roofing were implemented to optimize performance. The project led to a 15% increase in energy yield, demonstrating the feasibility and effectiveness of bifacial modules in urban environments.

Case Study 3: Bifacial PV Modules in Snowy Environment

A third case study brings us to Canada, where a solar park was set up in a region with heavy snowfall. The snow-covered ground, with its high reflectivity, provided an ideal environment for the bifacial modules. The result was an impressive 30% boost in energy output during winter months, showcasing the potential of bifacial modules in snowy climates.

Future Prospects and Challenges for Bifacial PV Modules

Prospects

Bifacial PV modules show great promise for the future, with potential applications in diverse areas, from residential rooftops to large solar farms. With ongoing research, the efficiency of these modules is expected to continue improving, and the costs may decrease further, making them even more viable for widespread adoption.

Challenges

One of the main challenges facing bifacial PV modules is the need for a more standardized approach to performance assessment. There’s a need for comprehensive, globally accepted standards to assess and compare the performance of different bifacial modules.

Additionally, accurately predicting the performance of bifacial PV modules can be complex due to factors such as variable ground reflectance and the impact of shadows.

Bifacial Modules in the Market Context

Current Market Scenario

Bifacial PV modules are increasingly gaining traction in the solar market due to their superior performance. However, they still represent a small portion of the total solar modules market. Market dynamics, including supply and demand factors, policies and regulations, and competition, are all at play.

Market Forecasts

Given the increasing emphasis on renewable energy, the market for bifacial PV modules is expected to grow significantly in the coming years. A shift towards more energy-efficient technologies and sustainable practices will likely drive this growth.

Regulatory Landscape for Bifacial Modules

The regulatory landscape for bifacial PV modules varies globally. Policies and incentives can significantly impact the adoption of bifacial technology.

United States Regulations

In the United States, regulations surrounding solar power, including bifacial PV modules, are mainly shaped by federal and state-level policies. The Federal Investment Tax Credit (ITC), which provides tax credits for solar energy systems, plays a significant role in promoting the adoption of solar technology. Bifacial modules, being part of the larger solar industry, benefit from this policy.

Understanding these regulatory landscapes is crucial for stakeholders across the board. Manufacturers need to ensure their products meet regulatory standards, developers must navigate policies that impact project feasibility and profitability, and installers must comply with local installation codes and guidelines.

Conclusion: The Impact and Future of Bifacial PV Modules

The introduction of bifacial PV modules marks a significant advancement in solar technology, opening the door to more efficient use of solar energy. While there are complexities and challenges associated with their adoption, the potential benefits of these modules are substantial. As we continue to transition towards renewable energy, bifacial PV modules will play an increasingly important role in this journey.

With a comprehensive understanding of the working of bifacial PV modules, the factors influencing their efficiency, and their potential impact, industry professionals and enthusiasts alike can navigate this exciting field with a more informed perspective.

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Shanika Wickramasinghe
Shanika Wickramasinghe

Written by Shanika Wickramasinghe

Senior Software Engineer and Freelance Technical Writer. I write about any Computer Science related topic. https://www.linkedin.com/in/shanikawickramasinghe