Science study tracks real‑world perovskite module degradation, offering data manufacturers can use in warranties

A team led by the Swiss Federal Institute of Technology Lausanne and the U.S. National Renewable Energy Laboratory reports in Science today that perovskite solar mini‑modules degrade in predictable ways that can be tied to climate stressors and encapsulation choices. The authors tracked field performance for more than 24 months at sites in Arizona, Switzerland, Singapore, and Saudi Arabia, then mapped electrical loss to identifiable mechanisms such as moisture ingress and ion migration.

The timing matters because perovskite‑silicon tandem products are leaving pilot lines and entering early installations in Europe and Asia. Banks and developers have lacked bankable field data to set warranties and levelized cost assumptions, so quantified degradation rates can reduce financing risk.

The study combined IV curve tracing, electroluminescence imaging, and mass spectrometry of encapsulant layers to separate reversible from irreversible loss. Glass‑glass laminates with edge seals outperformed polymer backsheets in humid sites, and thermal cycling aggravated series resistance in arid hot sites. The team reports that modules built with 2D perovskite surface passivation saw lower drift in open‑circuit voltage, consistent with ion migration suppression documented in earlier lab reports.

Co‑corresponding authors include Michael Grätzel at EPFL and Laura Schelhas at NREL. Devices were fabricated across partner labs, including the Helmholtz‑Zentrum Berlin and the University of Oxford, then packaged to International Electrotechnical Commission 61215 test protocols before deployment. The authors note that observed T80 lifetimes varied by more than a factor of two across climates, but failure signatures were consistent enough to incorporate into physics‑based warranty models.

The paper references prior accelerated testing work in Science and Nature Energy that pointed to moisture as a dominant driver of perovskite degradation. It extends those findings by correlating field humidity and temperature profiles with in situ performance and post‑mortem analytics. Lead leakage from fractured cells remained below detection limits for glass‑glass modules with ion‑exchange layers, the team reports, a point that will interest regulators evaluating installation guidelines.

Engineering teams can use the dataset to choose encapsulants and edge seals for site‑specific conditions, and to calibrate maintenance schedules to reversible degradation components. The authors publish raw data and a simple degradation parameterization that can plug into yield assessment software used by independent engineers.

For the technology landscape, field‑validated degradation models narrow the gap between lab efficiency records and bankable energy yield. That creates a clearer path for manufacturers scaling tandem lines, for insurers writing performance guarantees, and for policymakers updating standards that govern installing and recycling perovskite‑containing modules.