- #1
stefanomoret
- 7
- 0
Hi all,
I have a doubt which I would like to hear your opinion and answers about.
So, I was comparing different light sources for my research, and I started thinking about a sentence which I've always taken for granted: incandescent light bulbs waste more than 90% of their power as heat (wikipedia).
Now, for sure the sprectrum of an incandescent is mostly in the infrared region, and that's why it has such a low "luminous efficacy", but isn't at the end ALL the power emitted converted into heat? I mean: what are we referring to when declaring that a bulb wastes a certain percentage of its emitted power as heat? Is it because radiation at different wave-lengths transmits different amounts of heat?
For my understanding, a 100W bulb will emit 100W of heat. The visible ratio (taken into account by luminous efficacy, [lumen/W]) is just the amount of radiation which we can see..
Thanks for any comment, cheers!
Stefano
I have a doubt which I would like to hear your opinion and answers about.
So, I was comparing different light sources for my research, and I started thinking about a sentence which I've always taken for granted: incandescent light bulbs waste more than 90% of their power as heat (wikipedia).
Now, for sure the sprectrum of an incandescent is mostly in the infrared region, and that's why it has such a low "luminous efficacy", but isn't at the end ALL the power emitted converted into heat? I mean: what are we referring to when declaring that a bulb wastes a certain percentage of its emitted power as heat? Is it because radiation at different wave-lengths transmits different amounts of heat?
For my understanding, a 100W bulb will emit 100W of heat. The visible ratio (taken into account by luminous efficacy, [lumen/W]) is just the amount of radiation which we can see..
Thanks for any comment, cheers!
Stefano