Also the side question is how many Joules is one photon (any between 450-660nm). Thank you
P.S. I am asking because I want to estimate how much thermal energy should be dissipated by LED when part of known energy is emitted as light.
P.S. Got an answer from Robert. Thank you. So those 6500 Lumen 100Watt white LED arrays emit about 9 watt of energy in photons alone and rest 91W goes into heat. Not bad.