See also: “Four Light Bulbs”
I’ve installed incandescent-replacement bulbs (actually halogens in an A19 form factor) to wipe out my riding electricity with “nega-watts.” Halogen “incandescents” work well for stairs, attics, closets, bathrooms, etc. where compact fluorescents don’t really make sense. CFLs don’t like frequent on/off cycles, nor extreme temperatures, nor are most of them dimmable. So… where do they make sense?
A surprising number of places, it turns out (for many people). People complain that CFLs don’t last as long as claimed. It’s often stated that CFLs may last 10,000 hrs- over a year of continuous operation, or a few years in most people’s daily habit. But here’s the funny thing: even if a CFL only lasts as short as an incandescent (barely a thousand hours), you still make your money back. In electricity savings alone, the CFL efficiency gain (a factor of 4) already makes up for its higher purchase price. People who complain about that one-time cost apparently won’t (or can’t) do the math on total cost of ownership (TCO). If a CFL, then, lasts any bit longer than an incandescent, that becomes pure profit.
Let’s run through it: a CFL cuts power to a quarter that of an incandescent. That incandescent lasts about 600-900 lit hours. The US average rate is 12 cents per kWh- some more, some less. A 60-Watt incandescent bulb then costs $4.32-6.48 in electricity alone over its life. Assuming no gain in lifetime at all, the CFL replacement must cost no more than 3-4 dollars extra (the electricity cost, times the 3/4 power cut).
That breakeven point has already been reached, and CFLs win on TCO. If you’re paying five bucks per CFL bulb (and they’re not specialty lights like high-color rendition) you need to shop around more. 14-Watt CFLs (60W equivalent) are under four dollars each in multi-packs, and even less by internet/mail order. They do use more materials, so there’s more embodied energy than an incandescent. But we haven’t counted the higher air conditioning needed to dissipate the extra wattage that incandescents waste. Nor transmission losses on that extra 45 Watts… or the air conditioner’s many watts. Nor have we assumed any lifetime gains at all, which also translate into labor savings- who likes getting out the stepladder, and changing bulbs? Since lights are, by definition, energy devices, their throughput in Watts over the years will overwhelm the extra energy of materials.
It is then the user’s responsibility to let the CFL last longer, to rack up even more positive gains. Pick reputable manufacturers. Avoid using them in closets or storage-only rooms; bulbs are tested using 3-hour on/off cycles. (I’ve seen one manufacturer explicity state “15 minute” minimum cycles.) Avoid extreme temperatures, such as tight fixtures with little airflow. (Efficient bulbs help, since less wasted power means less heating.) Avoid vibration. Certainly don’t use dimmers or 3-way switches with bulbs that don’t say “dimmable” or “3-Way.”
Oh, and about that mercury thing. People complain about CFLs containing hazardous mercury, when the amount is measured in milligrams. I’ve heard one pundit state flat-out that CFLs are “filled with mercury.” Needless to say, I don’t take that pundit seriously; I had previously taken advice of his that turned out to be worthless. He was later caught on camera admitting he’s a troll, and likes to sling the crap just because. The amount of mercury in a CFL is not zero, but nowhere near worthy of hysteria. And if you install these units in good locations like I’ve mentioned, there won’t be many bulbs and milligrams to dispose in the first place.
No, the greatest issue with me is that I simply don’t have places to put more CFLs. I already use small LEDs for task lighting, such as desk lamps and the kitchen counter. I’ve put those halogens I mentioned in my bathrooms, closets, and stairs where they make more sense than CFLs. All I’ve got left are a porch light (100 incandescent Watts, reduced to 23W) and my workshop (60 to 14W). That’s 119 nega-watts, and I’m now up to around 225 total. There simply aren’t many places left where I leave a light on, of that size, for hours and hours. That, then, calls for a different type of “bulb”…