If it were possible to have an incandescent light based on a substance with a melting point far beyond that of tungsten, would it’s efficiency be comparable to fluorescent lights? My best efforts at research online suggest a black-body temperature of about 7000 K would be optimal.
There’s a table here which says that an ideal 7000K radiator has an efficiency of 95 lm/Watt, which is better than most CFLs, but not as good as the best LEDs.
Thanks for that link. The text says that 6600K would be ideal but they round it out to 7000K. Now though it occurs to me that electric arc lamps get around the need for a solid emitter, or is electric arc light not black-body in spectrum?