Why does replacing incandescent light bulbs with compact fluorescent bulbs conserve electricity?

Answer 1

Because instead of using a 40, 60, 75 or 100 watt bulb, you can get the same amount of light with using less electricity to run a fluorescent bulb. For example, if you are looking for the equivalent light output of a standard 100w incandescent, look for a 25w cfl (compact fluorescent light)

Another basic way to understand this is that incandescent bulbs produce a lot of heat along with the light they emit. They produce much more heat than the compact fluorescent bulbs. The heat from incandescent bulbs doesn't just come from thin air; it is a product of the electricity that is consumed by the bulb. This heat is called 'entropy' because it is wasted energy; it represents expended energy that can never be recaptured to do other things. The compact bulbs produce less entropy or wasted heat, and are therefore more efficient and environment friendly. If you are imagining that the heat from incandescent bulbs could very well be 'captured' and used for other things, realize that the 'capturing' process must itself involve the expenditure of energy, and at every step there is a huge loss of efficiency. Heat can be collected, but never without a cost; that cost is entropy.