NREL Certifies First Commercially-Viable Perovskite-Silicon Tandem Cell at 33.2% Efficiency

The National Renewable Energy Laboratory has certified a perovskite-silicon tandem solar cell at 33.2% efficiency produced by a manufacturing-compatible process, marking the first time a cell in this technology class has been certified at efficiencies above 33% under conditions consistent with commercial fabrication rather than laboratory optimization only. The cell uses a 1.68 eV bandgap perovskite top layer paired with a silicon heterojunction bottom cell, with a transparent recombination junction between layers. The certification is significant because prior record cells relied on small areas of under 1 cm² and processes incompatible with roll-to-roll or large-format manufacturing. This cell was produced on a 4 cm² substrate using a vapor-deposition process. Oxford PV, which holds several commercial perovskite tandem patents, stated it plans to begin US residential module qualification testing by Q3 2026 at its Brandenburg, Germany facility, with US-market modules projected for 2027. First Solar, the dominant US-headquartered panel manufacturer, has disclosed an internal perovskite-on-CdTe tandem roadmap targeting 2028 commercial availability. At 33%+ efficiency, a standard residential array footprint could generate 35–40% more power, significantly improving economics for space-constrained rooftops. Stability and 25-year durability certification remain the primary commercial hurdles for perovskite technology.