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Wal-Mart Is Pushing Compact Fluorescent Bulbs
While we all know from reading the internets that Wal-Mart is irredeemably evil, the world's largest retailer has committed to get compact fluorescent lightbulbs into 100 million homes this year. CFLs are found in only 6% of households today. These energy-saving bulbs use 75% less electricity than incandescents and produce far less greenhouse gas to manufacture and use. Wal-Mart seems determined to use its marketing prowess to do what hasn't successfully been done in the CFL's 25-year history: to convince consumers to pay more upfront for large savings over the product's lifetime.
The delay is pretty much a thing of the past. The ones in my house turn on instantaneously, as far as I can detect. If they are very, very cold (way colder than you'd ever let it get inside your house), it can take maybe half a second.
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Regular bulbs are cheaper to produce - namely because they don't need a ballast (what is hidden in the base in CFLs) like all fluorescents do. Price a replacement ballast at homedepot for a digital (T32?) fluorescent - it costs between $16-25 for four tubes, sometimes more. So I'm surprised they CFLs got so cheap.
BTW, 60 watt equivalent CFLs cost roughly $1.50 a piece (8 pack) at Costco. Much cheaper than Walmart. Nice, bright, instant on.
(A while back, in my dad's new garage, within 3 weeks - 6 of his fluorescent tube fixtures broke. It was a batch of bad ballasts in them. It would have been a bitch replacing just the ballasts - lots of cutting wires, tying the new one together, tearing the fixture apart and putting it back together again - in other words a PITA. We decided to go with regular bulb fixtures with CFLs because we would get the fluorescent cost benefits but the screw in bulb convenience.)
Anyway, the upfront cost is not worth complaining over - with regular use you got your money back within 3-5 months.
Guess what? There is a delay.. maybe a second or so - and then on top of that it takes them about a minute to get up to full brightness. So the 100W equivalent CFL's I have put out (guesstimate) 20W of incandescent equivalent light. I keep my house at 70F. When the bulbs have been operating and are up to about (guesstimate) 100F, they turn on with about a 1/4 second delay. Who keeps their house at 100F?
This makes them inappropriate for stairwells, bathrooms, and any place with automatic light sensors.
"I don't know that atheists should be considered citizens, nor should they be considered patriots." George HW Bush
AFAIK, the two main quality issues with fluorescent lights are:
With CFLs, the ballast frequency issue was solved a long time ago. Basically, the voltage needs to be stepped up way higher than line voltage (120V in the US, 220V many other places). The low-tech way to do this is with a transformer. This means you get 60 Hz (or 50 Hz, whatever) current at that high frequency. That means flickering. Flickering doesn't happen with incandescent bulbs because it is heat of the filament that is causing the light to be emitted. The electrical current going through the bulb goes to zero 120 times a second (with 60 Hz power), but the filament's thermal mass is high enough that the bulb "coasts" through the zero voltage (and zero current) crossing and continues to emit light. You can even turn off an incandescent and watch it continue to glow for a fraction of a second after power is removed, because it takes time for the filament to cool. But this continuous lighting thing is not the case with a fluorescent, as I understand it. The gas in the tube only produces light when there's a voltage, and it stops pretty much instantaneously when it's not being electrically excited. Thus, with a fluorescent and a low-tech ballast, you get an effect similar to what it looks like when your monitor is set at a painfully low refresh rate, only not quite as bad, but still annoying.
But, as I said, compact fluorescents don't suffer from this issue. The reason is they have electronic ballasts. Instead of simple, dumb circuit with a transformer in it, they have a circuit that steps up the voltage, but it converts it to a much higher-frequency A/C voltage before it gets into the tube. I'm not sure of the frequency, but googling indicates it is in the tens of thousands of Hz. So, it's fast enough your eye really can't perceive it.
The other issue, color temperature is a little different story. As this explanation says, "Warm light is preferred for living spaces because it is more flattering to skin tones and clothing." I think this is the key reason for aesthetic objections to CFLs. Incandescents produce warm light at a color temperature of about 2700K, because that's what happens when you heat up a filament. With compact fluorescents, different options are available. If you want something similar to what you're used to with an incandescent, you should choose a 2700K CFL! It's not at all uncommon for CFLs to come in color temperatures in the range of 4000K or 5000K. That will appear considerably bluer or even weird and greenish compared to an incandescent. Nobody wants their skin tone to appear overly greenish, so 2700K it is, for aesthetic purposes, in most cases.
On a side note, things are different if you want to, say, take pictures of things. In that case, you might want to go with a higher color temperature, because 2700K is considerably warmer (yellower) than what you see outside on a nice sunny day.