At a party when some bore says that compact fluorescent lamps use more energy across their lifetime than incandescent lamps. I wasn't going to argue with someone with such a startling lack of economic thinking, but the view seems surprisingly widespread.
Let's start simply. After purchase the fluorescent uses 8W, the incandescent uses 60W. The fluorescent lasts longer than the incandescent. So the fluorescent uses less energy after purchase.
Prior to purchase the more complex fluorescent is going to use more energy to manufacture, but how much more? Well, energy isn't a free resource, so in a free market the energy used to create the good is included in the price of the good. So, the fluorescent uses less than $3 in energy, the incandescent less than $0.10. So the fluorescent has to save $2.90 across its operating life to make up for the additional energy taken to create it, which it does.
That leaves us with two externalities. Pollution generated during the manufacture of the fluorescent and pollution generated by the disposal of the fluorescent. My guess, for which I have no proof, is that the costs to the community of these two externalities do not differ by 30x between the incandescent and the fluorescent, which is what it would take to change the superiority of the fluorescent.
Updated: spelling corrected