Perovskite-Based Tandem Photovoltaics for Space Power: Whole-Stack Radiation Response, Balance-of-Array Limits, and Mission-Specific Design

Satellite constellations, lunar infrastructure, high-power electric propulsion spacecraft, and deep-space missions increasingly require photovoltaics that combine high efficiency, low mass, and radiation tolerance. This review evaluates perovskite-based tandems at completed-stack and array levels rather than treating perovskite absorbers in isolation. Tandem-level irradiation studies span approximately 1% to above 94% retained efficiency under different test conditions, showing that bottom cells and recombination layers can control radiation survival. Using ASTM reference spectra, representative two-terminal bandgap pairs show a 2.0–9.9% AM0 shift in top-to-bottom photocurrent ratio and a 0.95–4.46% estimated penalty if AM1.5G-matched stacks are flown without retuning. An illustrative balance-of-array analysis gives crossover masses of 1.3–2.8 kg m−2 relative to a substrate-based III–V/Ge reference. Replacing that comparator with a measured thin-film IMM4J benchmark moves parity for the all-thin-film perovskite cases to below approximately 0.2 kg m−2 under a matched protective mass assumption. Because tandem-level retention endpoints do not identify separate sub-cell degradation functions, differential degradation is treated analytically as a buffered-versus-exposed current-matching problem rather than assigned architecture-specific integrated losses. The review concludes with mission-specific modeling, diagnostics, and qualification recommendations.