A team led by Geon Kim, Seongho Song, Joshua S. Stein, Wanyi Nie and Namyoung Ahn now reports in Communications Engineering an optical and thermal modeling framework designed to address exactly this problem. The framework simulates angle-dependent transmission and absorption spectra and the resulting photocurrents, taking into account the perovskite composition used in the top cell.

Crucially, the model does not stop at static, lab-style illumination. This allows the researchers to evaluate how a tandem cell would actually perform under realistic on-orbit conditions rather than under idealized laboratory lighting.

Using this framework, the team identified optimal perovskite top-cell structures for different satellite types, with the best choice depending on the perovskite composition and the temperatures encountered in orbit. In other words, there is no single universal design: the ideal absorber varies with the mission profile it must serve.

The simulations also revealed a clear trend with bandgap. A higher perovskite bandgap increases the matched photocurrent, the voltage, and the projected efficiency of the tandem device under AM0 illumination, the solar spectrum relevant to space applications. This gives cell designers a direct lever to pull when aiming for maximum in-orbit power generation.

Thickness, however, involves a trade-off. The study found that a broader tolerance for current matching between the two junctions comes at the expense of a larger optimal absorber thickness once on-orbit thermal conditions are taken into account. Designers must therefore balance manufacturing flexibility against the penalties of thicker absorbers under real thermal environments.

The authors position the work as a set of design guidelines for tailoring tandem solar cells to achieve the highest power generation while accounting for satellite motion. Because the article is being shared early as a peer-reviewed, accepted, citable version with a permanent DOI, the framework is already available to the community, though the final Version of Record may include further edits.

Subject of Research: Optical and thermal simulation of perovskite/silicon tandem solar cells for satellite power systems

Article Title: Photonic simulation and design framework for optimizing perovskite/Si tandem solar cells for satellite power systems

Article References: Kim, G., Song, S., Stein, J. S., Nie, W., & Ahn, N. (2026). Photonic simulation and design framework for optimizing perovskite/Si tandem solar cells for satellite power systems. Communications Engineering. https://doi.org/10.1038/s44172-026-00813-2

Image Credits: AI Generated

DOI: 10.1038/s44172-026-00813-2

Keywords: perovskite, silicon, tandem solar cells, satellites, photovoltaics, simulation, bandgap, orbital temperature, AM0 illumination, space power, Photonic, design