In a groundbreaking achievement that promises to revolutionize the solar energy industry, a team of researchers from the Fraunhofer Institute for Solar Energy Research ISE and the NWO-Institute AMOLF in Amsterdam have unveiled a multijunction solar cell with an astonishing efficiency of 36.1 percent.
This remarkable milestone was presented at the European Photovoltaic Solar Energy Conference (EU PVSEC) in Lisbon on September 21, 2023. Funded through the Fraunhofer ICON program, this achievement represents the culmination of years of collaborative research, pushing the boundaries of solar cell technology.
Albert Polman, who led the AMOLF portion of the project, noted that this achievement was the result of a unique synergy between two renowned teams. The Fraunhofer team is known for their expertise in ultra-high efficiency solar cells based on silicon and III-V semiconductors, while AMOLF brings extensive experience in optimizing light management within solar cells.
A Historic Collaboration
The journey towards this groundbreaking achievement began in 2020 when the Fraunhofer and AMOLF teams joined forces. Frank Dimroth from Fraunhofer ISE emphasizes the importance of this collaboration, highlighting that it combines the best available processes to realize a new efficiency record for a silicon-based multijunction solar cell. He credits both the new back reflector developed by AMOLF and the improved GaInAsP middle cell from Fraunhofer as key contributors to this remarkable achievement.
Overcoming Silicon’s Limitations
Silicon-based solar cells are ubiquitous, but their fundamental efficiency is limited to 29.4 percent. However, this limitation can be surmounted by employing a “multijunction” approach. In this design, multiple light-absorbing layers are stacked atop each other, with each layer effectively capturing a specific portion of the sunlight’s color spectrum. This approach dramatically enhances the cell’s overall efficiency.
Innovative Materials and Light Management
The record-breaking multijunction solar cell combines a cutting-edge “silicon TOPCon” solar cell and a high-efficiency cell design developed at Fraunhofer ISE with two semiconductor layers made of gallium indium phosphide (GaInP) and Gallium Indium Arsenide Phosphide (GaInAsP), also developed at Fraunhofer ISE.
This layer stack is then coated with a specially designed metal/polymer nanocoating crafted at AMOLF and jointly fabricated at both AMOLF and Fraunhofer ISE. The back reflector significantly enhances light trapping within the solar cell, marking the first time that efficiency has exceeded 36 percent.
New Horizons and Applications
While these ultra-high efficiency solar cells are currently more expensive to manufacture than traditional silicon solar cells, which achieve efficiencies of up to 27 percent, their potential applications are far-reaching. Particularly in situations where space is limited, and a significant amount of solar power must be generated within a small area, these multijunction cells hold immense promise. Solar-powered electric cars, consumer products, drones, and other emerging technologies stand to benefit greatly from this newfound efficiency. Moreover, the innovative light management design can be adapted for use in various types of solar cells, including silicon-perovskite multijunction solar cells, promising further advances in solar energy generation.
The collaboration between the Fraunhofer Institute for Solar Energy Research ISE and NWO-Institute AMOLF has yielded a historic achievement in the field of solar energy. Their record-breaking multijunction solar cell with an efficiency of 36.1 percent paves the way for more efficient and sustainable solar power generation, opening doors to a wide range of applications in the solar industry. This accomplishment underscores the importance of international research collaboration and innovation in addressing the world’s energy challenges, bringing us closer to a sustainable energy future.
reference link : https://www.ise.fraunhofer.de/en/press-media/news/2023/silicon-based-multijunction-solar-cell-reaches-record-efficiency-of361-percent.html#:~:text=Conference%20Paper%20EUPVSEC%202023