A team of nanoengineering researchers from the University of Lund, Sweden, has made a significant breakthrough in the construction of photovoltaic nanowires, an alternative to traditional photovoltaic cells, using three different materials that are better adapted to the solar spectrum compared to conventional photovoltaic cells. current silicon solar cells.
These nanowires are lightweight and require little material per unit area, which is why they were recently put to the test on a satellite.
Photovoltaic nanowires, a new alternative that is being tested on a satellite
The combination of efficiency and low weight is crucial in space. This new tandem-arrayed solar cell technology is aimed at greatly improving the efficiency of commercial silicon solar cells, possibly up to twice their capacity.
The interest in investigating this technology and developing a solution that applies it is related to the fact that silicon solar cells have reached their efficiency limit.
Lund researchers have developed a method to build extremely thin rods of semiconductor material on a substrate, which could reduce production costs and become a more sustainable alternative.
By using extremely thin rods of semiconductor material instead of materials synthesized on top of one another, nanowires require a much smaller amount of material per unit area. This could reduce production costs and therefore ensure greater sustainability. In addition, nanowires are lightweight and therefore suitable for installation in satellites where efficiency combined with low weight is essential to ensure adequate performance.
The solar nanowire rods, just one nanometer thick, are composed of three materials that contain different proportions of indium, arsenic, gallium, and phosphorus. In the laboratory, the researchers have achieved an efficiency of 16.7%. However, Yang Chen, another researcher in the area, has shown that nanowire solar cells can achieve 47% efficiency with the current structure. To achieve even higher efficiency, the triple diodes will be optimized and attempts will be made to reduce the surface effect of the nanowires.
One aspect that works in favor of this project for its intended purpose is that nanowire solar cells are durable and can better withstand harmful radiation in space, compared to film-based tandem solar cells. Recently, examples of this technology were installed on a research satellite sent into space during the second week of January by the California Institute of Technology, who are partners in this initiative. The results of the tests carried out on the orbiting satellite will be received continuously and will be reported during the coming spring.
