Imagine picking up a bag of dog food... or three. Or six fat cats. That's about 100 pounds, and that's how much carbon dioxide this innocent little 60 watt light bulb puts into the atmosphere before it burns out. In comparison, a compact fluorescent, or CF, light bulb will last about 10 times as long before it needs to be replaced and keeps 80% of the CO2 out of the atmosphere.
We've heard it all before: CFs flicker! the color of the light is icky! they're too bright! they're too dim! But consider this: today's compact fluorescent CF bulbs are much improved from those that were available just a few years ago: you can even find dimmable bulbs.
Before you go shopping, here are two terms you should know.
Lumens
Brightness is measured in lumens:
One candle puts off about 12 lumens
Most 60-watt incandescent bulbs are about 640 lumens
Most people are used to buying bulbs by wattage, and manufacturers of CFs have tried to allow for this by indicating equivalents. But these seem to vary between brands: a 60 watt bulb may be equal to a 11, 13, or 15 watt CF. Compare lumens instead -- it should be printed somewhere on the package -- and you'll know what to expect.
Color Temperature
image via wikipedia article linked below
Whether light seems warm or cold is measured in degrees Kelvin:
1850 K, very warm, like candlelight
2800 K, warm, like incandescent light
3000 K, warm and "bright," like halogen light
5000 K, daylight at noon
Color temperature is complicated: Wikipedia explains it well if you’re interested. In short, to get a warm, cozy glow, look for bulbs with a color temperature of 2800 K; this is the same as old fashioned incandescent bulbs. For a brighter, whiter light, more like halogen, look for bulbs around 3000. New “daylight” CF bulbs go towards 5000 K and emit a very blue light that makes some people feel more cheery. The better manufacturers print the degrees kelvin information on the package; if it’s not there, ask, or buy another brand.
ok, cool--have them, use them. but can we talk mercury? i'm curious to have someone (who's not me) parse those facts. from what i've read, we could have an even worse nightmare on our hands when these break and/or hit the landfills.....
view ValerieNYC's profile
ValerieNYC,
I just happened to read this article in the Green Guide last night. It satisfied my mercury worries. (Although I have broken a CFL bulb in a walk-in closet, and immediately cleaned it up mostly using my bare hands....)
http://www.thegreenguide.com/doc/ask/cflmercury
view Sea's profile
I've been using these light bulbs forever and have never had the 'flickering' problem people always complain about.
Also, as far as dimmable pretty inefficient. I believe that at least 1 way a dimmer works is that it switches the light on & off incredibly quickly so as to create the effect of having less light. check out http://www.treehugger.com/files/2007/04/dimmer_switches.php
for a better explanation and more info...
view Beck's profile
does anyone know where I can get high powered dimmable CFLs in the white shades (5000k)?
i wish i'd read this before i spent a fortune getting the highest powered LED lights I could find...
my kitchen now feels like a 160 lumen igloo.
view the big d's profile
There is a website, of which I forget what it's called and I may have it in my favorites on my home computer. It's a website that not only sells bulbs, but rates them, especially CFL's. What is great about that site is that it lets you know which bulbs are best suited for various situations, tempurature as some bulbs, even now, cast a bit of a green or orange tint, rather than something comperable to a traditional warm white incadescent bulb.
Some bulbs with really low mercury may start out dim but get bright over a minute or so (I have some Par30 CFL's that are like this) and most CFL's don't flicker to life when first turned on although some may still and I've not had the flickering issue with them once on, now some may blink when going bad, others will just stop working entirely, just like that.
I'm all for them for many reasons, namely the reduced energy and heat they require/produce in comparison to an incadescent bulb.
If I can find the link, I"ll post he here.
view ciddyguy's profile
thanks ciddyguy.
hopefully i can resolve my lighting situation soon. i'm all for going green, but LEDs give off barely any light.
view the big d's profile
I've heard that the life of the CFL is lessened if you turn it on/off a lot.
Can anyone verify what I've heard?
Based on hearsay, I've only switched out a few bulbs to CFLs...
view JenPDX's profile
JenPDX,
Yes, they do have a (maybe only slightly) shorter lifespan. I don't know the numbers, but the ballast wears out. However, I've read that they are still better to use than incandescents. I have three CFLs above my bathroom mirror, and I'm very happy with them. It's been three years (!) since I put them in, and only recently have I noticed that they are taking longer than usual to 'warm up' when I switch them on. All that on an off has been wearing them down a bit, but they're still really great.
view Sea's profile
Thanks for linking to that article, Sea.
I wish this post had come a few weeks ago, before I found myself, mouth agape, in an asile filled with CFLs wondering what the heck I needed! Went by the wattage equivalents, but the bulb gave off an eerie blueish light that I couldn't deal with. I was a bit crestfallen at the thought that all CFLs were that way. But I went back and managed to find one that was much better. Just waiting now for the front porch light to burn out so that I can put the weird blue one there.
view J's profile
n-Vision brand CFLs won the Popular Mechanics side-by-side test hands-down, and I installed several. Report: they turn on to full brightness immediately, and emit roughly the same color as an incandescent. I've had several guests give me a surprised remark when they realize that the entire floor is CFLs, as they didn't pick up on it until they saw the bulbs themselves.
view CJL's profile