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A lightbulb's energy consumption and heat emission don't seem intuitive to me at all.


Doesn't an e.g. 60W lightbulb output 60W of heat? I can't see any reason it wouldn't just be 1:1.


It's not so simple anymore. Now you have a 60W (equivalent) bulb outputting 9 watts.

If you ignore the numbers you can still easily feel the heat, but it's not so easy to translate into human equivalents.


Yes, human equivalent is the key. Even if 60W is 60W, how much is that in the feeling I get on my skin?


Isn’t that because in that case, 60W refers to the legacy socket size rather than the power output?


No, it refers to the legacy light output of a 60W incandescent bulb.

You can get a large range of wattages for one socket size.


I see. It's still a fact though that the energy output is the same as the heat output.


Close enough to the same, but that number is now a footnote on the box instead of the primary selling point.

The average person, when asked how many watts that bulb is, is probably going to say "60" or "much less than 60 but I don't know how much".




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