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Will a perovskite on silicon tandem solar cell be certified at 36% efficiency or higher by June 30, 2027?

Answer in 248 days

How this resolves: Resolves Yes if, on or before June 30, 2027, a company or research group publicly announces a perovskite on crystalline silicon tandem solar cell with a power conversion efficiency of 36.0% or higher, certified by an independent test lab such as NREL (National Laboratory of the Rockies), ESTI, Fraunhofer ISE CalLab, ISFH or JET.

Closes Jun 29, 2027, 15:00 UTC (12:00 BRT)

Why it matters

Stacking a thin perovskite layer on a silicon cell lifts the theoretical limit to about 43%. LONGi holds the record at 35.5%, certified by the European Solar Test Installation in July 2026, after climbing from 33.9% in late 2023.

Question provenance

How this question entered the record and how it will be resolved.

Resolution criteria
Resolves Yes if, on or before June 30, 2027, a company or research group publicly announces a perovskite on crystalline silicon tandem solar cell with a power conversion efficiency of 36.0% or higher, certified by an independent test lab such as NREL (National Laboratory of the Rockies), ESTI, Fraunhofer ISE CalLab, ISFH or JET. Resolves No otherwise.
Expected resolution
Jun 30, 2027

Key evidence

  • LONGi, July 15, 2026: 35.5% crystalline silicon perovskite tandem cell certified by ESTI, a new world record
  • pv magazine, September 10, 2026: LONGi still holds the tandem cell record at 35.5%

Skeptical perspective

Gains near the top come slowly, and the record moved only 0.65 points between April 2025 and July 2026.

What could change the outlook

  • The next edition of the Solar Cell Efficiency Tables
  • Results announced at SNEC or other industry conferences in 2027
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How does this question resolve?

Resolves Yes if, on or before June 30, 2027, a company or research group publicly announces a perovskite on crystalline silicon tandem solar cell with a power conversion efficiency of 36.0% or higher, certified by an independent test lab such as NREL (National Laboratory of the Rockies), ESTI, Fraunhofer ISE CalLab, ISFH or JET. Resolves No otherwise.

When does this question close?

It closes to new calls on June 29, 2027.