re power factor see comments on http://mapawatt.com/2009/03/30/the-cfls-i-buy/ re " you shouldnt have lights on long enough for the heat value to be significant" - but often lights are on for hours in a living room etc more <a href="http://www.ceolas.net#li6x" rel="nofollow">http://www.ceolas.net#li6x</a> re "I’m pretty sure the mercury pollution numbers already take into account the fact that 50% of energy comes from coal" No the EPA diagrams etc commonly used by ban proponents quoted assume 100% coal power use <a href="http://www.ceolas.net#li19x" rel="nofollow">http://www.ceolas.net#li19x</a> goes extensively into the mercury question - the problem is the use of data several years old unrelated to latest developments. In a nutshell: 1. We know where the ever decreasing coal power stations chimneys are and we can treat their emissions with ever increasing efficiency at lower costs. 2. Compare that with billions of scattered broken lights on dump sites, when we do not know where the broken lights are, and so we can't do anything about them.

These PR arguments have been repeated by the anti-lightbulb campaign since early 90's but that doesn't make them more true. * First of all CFLs are not 4 times more effective but perhaps 2 times (with light loss and power factor included in the calculation). So that cuts the emissions calculation in half right there. * Secondly, less than half of the energy comes from coal in the U.S. (48.5%) so that cuts the 50% of alleged incandescent 'mercury pollution' into less than 25% of claimed. * Deduce heat replacement effect during the winter and even that small difference dwindles into nothing. Left is the mercury-containing CFL polluting landfills unless each bulb is carefully recycled. CFLs may also constitute a health risk in case of breakage. That the content is 'only' 4-5 mg may sound like very little but there are no safe levels for inhaling mercury vapour. If 4-5 mg was truly insignificant for people's health would authorities issue such detailed guidelines on what to do if one breaks? Would Philips sells $100 spill kits to handle accidents: "Offers Customers the tools to handle the clean up of broken mercury containing lamps. The materials may be placed in a sealed plastic bag and sent to EPSI in the standard EPSI-PAK lamp recycle box. Kit includes a pail containing training video, safety data sheets, instructions, guidelines for clean-up, mercury chemical information, gloves, scraper, brush, pan, dust mask, safety goggles, sponge pads, plastic sealable bags and large plastic bags." http://www.earthpro.com/philips/ Not exactly reassuring as to the safety of their products, is it? ;)