Helmholtz-Zentrum Berlin

Silicon-perovskite tandem solar requires optimization of both approaches, and embodies the weaknesses of each. Meanwhile, the use of pure thin-film devices offers a cheaper, simpler, and more sustainable PV solution for the United States.

First Solar and its cadmium telluride (CdTe) technology dominate thin-film solar in the mainstream market. Valerie Thompson looks at the US-based business and the future of thin-film PV technology.

As efficiency records tumble and devices become more stable, Europe is seeing the beginnings of a race to commercialize high-efficiency perovskite-silicon tandem solar products, reports Valerie Thompson.

German scientists have investigated the role of surface texturing in perovskite-silicon tandem cells and have found that several new processes offer the ability to etch smaller, more uniform textures onto the surface of a silicon cell than today’s industry standard. This could help to ease the subsequent growth of a perovskite cell on top of the silicon, enabling researchers and manufacturers to target higher performance.

A group of researchers from Helmholtz-Zentrum Berlin (HZB) has achieved a new world efficiency record for a silicon-perovskite tandem solar cell, with a certified efficiency of 32.5%.

Qingdao University researchers have synthesized high-performance titanium dioxide-based anode materials with excellent cycling stability, while German scientists have used operando techniques to observe how solvated sodium ions embed themselves in electrodes.

A life-cycle analysis of perovskite-silicon tandem modules indicates that additional environmental impacts in manufacturing are more than offset by the higher energy yield over their lifetime.

An international team of scientists developed a technique to isolate individual sources of electrical ‘noise’ within a solar cell. Comparing the technique to being able to pick out a single voice within a 200-person choir, they say the technique will help to improve understanding of where efficiency losses occur within a cell, and effective ways to mitigate them.

Scientists in Germany demonstrated a slot die coating process for large-scale production of perovskite thin-film solar cells that achieved a maximum efficiency of 20.83%. Using an additive, and experimenting to find the optimal concentration, the group demonstrated improved control over the crystallization process – crucial for developing stable, repeatable processing.

German scientists have improved the scribing method to interconnect perovskite PV cells, in order to then upscale them into mini PV modules. They established suitable laser fluence ranges for nanosecond and picosecond lasers and found that the former results in higher efficiency levels.