Comment by qayxc

The innovation here is you have a system that emits monochromatic light, and you have solar cells tuned specifically for that bandgap, plus the system is also "naturally" concentrating because the light output is incredibly bright. 3000 suns vs 500-1000 suns in typical CPV, plus they also do waste heat recycling. End-to-end efficiency of 40% is definitely feasible as advertised.

Isn’t that for sunlight though? I imagine if you have a source that only radiates a single wavelength, you could make a collector for that specific wavelength that’s more efficient than some general case one. Could be wrong though.

It's only true for a single junction. https://en.wikipedia.org/wiki/Shockley%E2%80%93Queisser_limi...

Multi-junction cells beat that limit, but they're still horribly expensive to manufacture which confines them to niche uses like spacecraft.