It really depends how your electricity is generated, how you heat/cool your home, and your local climate. Each CFL/CFB has a tiny amount of mercury, but coal also contains a tiny amount of mercury. Recent studies proved that the "inefficient" old bulbs had a hidden GHG benefit if the electricity they used was generated cleanly and the heat source they offset was particularly dirty. If the local climate is cool and the above conditions are also present, the environmental (and economic) benefit of the more efficient fluorescent bulbs could be only half as great as advertised. If the climate is warm and the electricity generation dirty, however, CFLs are completely justified. I think the same goes for the original question. If care is taken, the benefits of efficient lighting outweigh the damages, especially when considering other emitters of mercury.
Scandinavial Gigolo, You are on the right track. I'll hint at this: what are other sources of mercury?
I haven't re-checked for modern estimates, but seem to remember late-1990s-era estimates that the mercury emissions from coal burned to light an incandescent bulb are in the range of 5x to 10X the amount of mercury in a CFL.
Correct - since at least half of the electricity is coal-fired, the mercury put in the environment is greater than what is in a CFB.
Considering that my local coal-burning power plant is among the top mercury polluters in the country, CFLs are a definite improvement. I also bought a bunch of insulation this weekend to reduce heating/cooling power usage.
The very question is based on the premise that the CFLs will be thrown away, right? Like most people I know, I recycle mine. Even though our local electricity has a lower proportion of coal generation than most regions, that makes the CFL the easy winner.
