Single-junction solar is approaching its physical ceiling. Stacked absorbers are how the industry breaks through it.
Silicon’s practical limit sits near 29%, and the certified-record curves have flattened to a crawl. The only way up is more than one junction: stacked absorbers, each optimized for a different part of the solar spectrum.
Darwin’s conviction is that the tandem era should be built on materials with a proven quarter-century field record — CdTe and its II-VI cousins as the foundation for tandem and multijunction devices targeting 28% and beyond.
Manufacturers, researchers, and investors — the roadmap conversation starts here.
