Space

Modern solar panels can harness not just ultraviolet light, but also visible and in some cases infrared. But all of these designs are built to harness the sun, which gives off most of its light in the green range and emits plenty of ultraviolet light. But most exoplanets orbit red dwarf stars, which have a peak brightness in the red or infrared and emit little ultraviolet.

If we want to visit nearby planetary systems, such as the Proxima Centauri system, then we'll need to have solar panels capable of harnessing red dwarf starlight.