I\'m confused with the latest home lightning bulbs. Understanding filament bulbs

Question

I'm confused with the latest home lightning bulbs.

Understanding filament bulbs was easy. For example take 220V, 100W filament bulb:

Power = V2/R Filament gets heated and emits energy in the form of light & heat. Whose sum is 100J per second. I'm getting a light energy of little less than 100J per sec. Its very clear!

Now lets take latest CFL :

How can it be equivalent to 6 filament bulbs in light and yet consume same amount of energy as a single bulb (or even less in some cases).

Isn't conservation of energy getting violated here? Isn't More light implies, more light energy implies more electrical energy consumption?

Explanation / Answer

Incandescent bulbs are tremendously inefficient in producing visible light. If you model the filament as a black body at 3000 C you will see that the majority of light emitted is in the infrared.

CFLs, on the other hand operate through the principle of fluorescence rather than incandescence, which means that less of the energy they consume is put out as heat.

Addendum: for some more concrete figures on just how much energy incandescents waste as heat, check these wikipedia page sections:Incandescent light bulb efficiency & Luminous efficacy examples. It would perhaps be more fitting to call them 'heat bulbs'.

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