Record 24.6% Efficiency Achieved in Solar Tandem Cells

• Revolutionizing solar energy, researchers unveil a CIGS-perovskite tandem cell with a record 24.6% efficiency, promising a brighter, sustainable future for renewable power innovation!

Researchers from HZB and Humboldt University Berlin have achieved a significant milestone in solar energy with a CIGS-perovskite tandem cell that boasts a record efficiency of 24.6%. This advancement has been verified by the Fraunhofer Institute for Solar Energy Systems. The innovative design combines a CIGS bottom cell with a top perovskite cell, achieved through optimized contact layers between the two.

The project was a collaborative effort involving TU Berlin master's student Thede Mehlhop and HZB researcher Guillermo Farias Basulto, who utilized advanced vacuum deposition techniques at HZB's KOALA facility. Prof. Rutger Schlatmann emphasized the team's expertise, expressing confidence that further developments could push efficiencies beyond 30% in the future.

What innovative techniques led to the achievement of 24.6% efficiency in solar cells?

• Tandem Cell Design: The innovative combination of CIGS (Copper Indium Gallium Selenide) and perovskite layers in a tandem configuration allows for better utilization of the solar spectrum, where each layer absorbs different wavelengths of light more effectively.
• Optimized Contact Layers: The team developed optimized contact layers between the CIGS and perovskite cells, which enhance charge transfer efficiency and minimize recombination losses, crucial for improving overall efficiency.
• Advanced Vacuum Deposition Techniques: The use of sophisticated vacuum deposition processes at HZB’s KOALA facility enabled precise control over the thickness and quality of the absorber layers, which is critical for maximizing light absorption and reducing defects.
• Material Interface Engineering: Researchers focused on engineering the interfaces between the different materials, which improved light management and charge transport properties, leading to higher performance levels.
• Enhanced Light Absorption Properties: The specific materials chosen for both the CIGS and perovskite cells possess excellent light absorption characteristics, allowing more sunlight to be captured and converted into electricity.
• Temperature and Environmental Stability: Significant strides were made in increasing the stability and durability of the perovskite layer under temperature fluctuations and environmental conditions, which enhances the long-term viability of the solar cell.
• Collaboration with Academia: The partnership between researchers from HZB and Humboldt University symbolizes the importance of interdisciplinary collaboration in pushing the boundaries of solar technology through combined expertise in materials science and engineering.
• Regulatory and Testing Validation: The achievement of efficiency claims by an independent verification from the Fraunhofer Institute lends credibility to the results, which encourages further investment and interest in advanced solar technologies.
• Future Scalability Potential: The methodologies and materials used can potentially be scaled up for commercial production, which is essential in making advanced solar technologies more accessible and economically viable.
• Ongoing Research and Development: Continuous research is planned to explore alternative materials and configurations that could further enhance efficiency, with the goal of surpassing the 30% efficiency mark in future iterations of these solar cells.