With the growing global demand for renewable energy and the construction industry's pursuit of green and low-carbon development, photovoltaic building integration (Building Integrated Photovoltaics, referred to as BIPV) technology is gradually becoming a research hotspot in the construction field. Among them, the crystalline silicon BIPV system has a dominant position in the BIPV market with its high efficiency, stability and reliability. However, how to further break through the efficiency limit of the crystalline silicon BIPV system has become a key challenge facing the current industry.
1. The current status and bottlenecks of crystalline silicon BIPV system
The crystalline silicon BIPV system combines crystalline silicon photovoltaic cells with building materials to form a product that can both generate electricity and be used as a building component. At present, the mainstream crystalline silicon BIPV products on the market include photovoltaic curtain walls, photovoltaic roofs, photovoltaic sunshades, etc. These products have played an important role in improving the energy self-sufficiency rate of buildings and reducing carbon emissions.
However, the crystalline silicon BIPV system still faces bottlenecks in improving efficiency. On the one hand, the conversion efficiency of crystalline silicon photovoltaic cells is close to the theoretical limit, and there is limited room for further improvement; on the other hand, factors such as the integration of BIPV systems and building structures, installation methods, and environmental adaptability also restrict the improvement of the overall efficiency of the system.
2. Technological breakthroughs: efficiency optimization from cells to systems
High-efficiency crystalline silicon cell technology
Although the conversion efficiency of crystalline silicon cells is close to the theoretical limit, a slight increase in efficiency can still be achieved through material innovation and structural optimization. For example, the use of new cell structures such as heterojunction (HJT) and tunneling oxide passivation contact (TOPCon) can effectively reduce carrier recombination losses, increase the open circuit voltage and short circuit current of the cell, and thus improve conversion efficiency. In addition, the research on perovskite/crystalline silicon stacked cell technology is also advancing, and it is expected to increase the efficiency of crystalline silicon cells to a higher level.
BIPV system integration optimization
The efficiency of the BIPV system depends not only on the performance of the cell itself, but also on the integration method of the system. The overall efficiency of the BIPV system can be effectively improved by optimizing the arrangement of the cells, reducing electrical connection losses, and improving the heat dissipation performance of the system. For example, the use of micro-pitch or gapless cell arrangement can reduce the shadows between cells and improve the light utilization rate of the system; the use of smart inverters and maximum power point tracking (MPPT) technology can ensure that the system can operate at the optimal efficiency point under different lighting conditions.
Enhanced environmental adaptability
BIPV systems need to adapt to various complex environmental conditions, including high temperature, high humidity, wind and sand, salt spray, etc. By improving the battery packaging materials and improving the mechanical strength and weather resistance of the components, the stability and efficiency of the BIPV system in harsh environments can be enhanced. For example, the use of bifacial crystalline silicon cell components can make full use of the reflected and scattered light on the surface of the building to increase the power generation of the system; the use of self-cleaning coatings or intelligent cleaning systems can reduce the shading of dust and dirt on the surface of the cells and maintain the efficient operation of the system.
3. Application innovation: Expanding the application scenarios of BIPV systems
Deep integration of building facades and roofs
By deeply integrating the crystalline silicon BIPV system with the building facades and roofs, the perfect combination of building appearance and power generation function can be achieved. For example, the use of colored crystalline silicon cells or customized cell patterns can make the BIPV system part of the building's exterior, enhancing the building's aesthetics and artistry; by optimizing the installation angle and orientation of the BIPV system, the solar energy resources can be maximized and the system's power generation efficiency can be improved.
Development of multifunctional BIPV products
In addition to traditional photovoltaic curtain walls and photovoltaic roofs, BIPV products with multiple functions can also be developed. For example, combining crystalline silicon cells with insulation materials to form BIPV components with insulation functions can reduce the energy consumption of buildings; combining BIPV systems with energy storage devices and smart grids to form microgrid systems can achieve self-sufficiency in electricity and access to the grid for surplus electricity, thereby improving energy efficiency.
Cross-industry cooperation and standard setting
Promoting the development of crystalline silicon BIPV systems requires close cooperation among multiple industries such as construction, photovoltaics, and electricity. By establishing a cross-industry cooperation mechanism and jointly developing new technologies and new products, the commercialization process of BIPV systems can be accelerated. At the same time, the formulation of unified BIPV system standards and specifications can ensure product quality and safety and promote the healthy development of the market.
4. Future Outlook: Efficiency Limits and Breakthrough Directions of Crystalline Silicon BIPV Systems
With the continuous advancement of technology and the continuous expansion of application scenarios, the efficiency limits of crystalline silicon BIPV systems are expected to be further broken. In the future, the development of crystalline silicon BIPV systems will show the following trends:
Continuous improvement in efficiency: Through material innovation, structural optimization and other means, the conversion efficiency of crystalline silicon cells will continue to improve, promoting the improvement of the overall efficiency of BIPV systems.
Further reduction in costs: With the expansion of production scale and the maturity of technology, the manufacturing cost of crystalline silicon BIPV systems will continue to decrease, improving their market competitiveness.
Intelligence and integration: Combine technologies such as the Internet of Things, big data, and artificial intelligence to achieve intelligent management and optimized operation of BIPV systems; promote the deep integration of BIPV systems with other building systems to form more efficient and intelligent green building solutions.
Policy and market drive: With the continuous increase in global support for renewable energy and green buildings, crystalline silicon BIPV systems will usher in broader market prospects and development opportunities.
As an important direction of photovoltaic building integration, the efficiency improvement of crystalline silicon BIPV systems is of great significance to promoting the green transformation of the construction industry and the development of renewable energy. Through technological breakthroughs, application innovation and cross-industry cooperation, we have reason to believe that the efficiency limits of crystalline silicon BIPV systems will be continuously broken, contributing to building a low-carbon, environmentally friendly and sustainable future.
