TreeHugger has a detailed guide to the compact fluorescent light bulb, telling you everything you’d ever wanted to know about them.
* Energy use: 60-80% less than incandescents
* Lifespan: 6,000-15,000 hours (6-15x longer)
* Cost savings: up to $30 over its lifespan
One of the most contentious points about widespread use of CFLs is that they contain small amounts of mercury. However, because CFLs use so much less energy than their incandescent counterparts, CFLs are responsible for less mercury contamination than the incandescent bulbs they replaced, even though incandescents don’t contain any mercury.