@BitTwister
>Amazing how some can't see the wood for the trees. It's NOT just about the alleged shiny end benefits: what about the more polluting manufacturing and disposal processes?
Do you know how much energy is used to manufacture them? Surely the glass would be the most energy-intensive part as it needs to be heated up so much? There is more glass in 6 normal bulbs than 1 CFL. Also, if you can buy them for about the same (or less than) 6 normal bulbs (tesco, wilko etc. sell CFLs for about 80p) then the materials and energy in is almost certainly lower than the other bulbs (CFL technology is covered by patents, so that will eat into some of the cost).
As for disposal/recycling - that's why we have the WEEE directive... Many of the new WEEE sites for householders will take CFLs and ensure they are disposed of/recycled safely. If this is not happening then the law needs to be tightened, but that's (yet) another issue for the politicians. *sigh*
> Yes, they contain about 4mg of mercury. That turns out to be less than coal fired power stations emit generating the extra electricity incandescents require.
Quick calc - http://igs.indiana.edu/geology/coalOilGas/mercuryInCoal/index.cfm says ~0.02mg mercury per kg coal. So 20 kg of coal would be needed.
http://science.howstuffworks.com/question481.htm says coal has an energy content of 6150kWh/ton, so 123kWh saved = 4mg mercury (assuming 100% conversion efficiency!)
Using standard figures taken from the side of the packet, for sake of argument:
Normal lightbulb = 100W x 1000h/year = 100kWh/year
CFL = 20W x 1000h/year = 20kWh/year
Saving = 80kWh/year (~£8)
So just over 18 months of use to "pay back" the mercury, if all of the energy in coal is converted to electricity (more like ~35% in the UK, rarely over 45% anywhere)
>Yes indeed - with compact flourescent bulbs you get to save money by creating an even BIGGER environmental mess, AND they can't be dimmed, AND they're slower to reach a decent brightness in a slightly cold environment. What a bargain.
Dimmable versions are available, eg: http://www.megaman.cc/global/products/product.php?sid=17
Warm up time depends on the bulb... Old ones used to be rubbish (even as recently as 6/7 years ago), but most new ones are fine. As with colour temperature - you get what you pay for. Bearing in mind Philips own a lot of patents on the technology, they'd be a good starting point for a decent bulb...
And yes they do last for years - some in my house have been going for the past 7 years without problems.