A 13 watt CFL uses a lot more power than what it claims.
 

Most CFL say they use 13 or 11 watts or what ever.
But what they dont tell you is that they run 0.5 to 0.65 power factor.
They use might use 13 watts but what they dont tell you is they around 23 volt-amps.
Now I have seen it said many times that "residential utility meters only read true power, aka wattage", yet I am able to prove other wise with a very simple test.
See :
http://ecorenovator.org/forum/36999-post7.html
A low power factor is bad for the power grid and bad power factor can produce resonance in your home power wiring which can cause problems with other electronics.
Plus when you run a higher power factor inductive devices use less power over all.
So in reality the metter is getting spun as if you are using a 23watt bulb, not a 13.

So much for being more efficient, they consume close to double the power they say and cause problems down the line.

PFC in the home environment is, for the most part, a scam.
KVAR Power Factor Correction in the Home is a Scam

I used to choose CFL's with the lowest Milliamp rating instead of wattage because if you do the math you can see that they are not the same ratings.
Now I use LED's and they are true to their labeling and use less power.

Here in NA, power factor is not part of the game in terms of electricity billing/consumption, especially with home electricity users.

So, even though CFLs, with their electronic ballast circuitry, typically rated between .53 ~.67 PF @ rated wattage, it's not being converted to PF=1 in your residential utility billing.

This PF issue is more of an "issue" if you live in certain European countries such as France, etc.

So, power correction for residential devices in NA is, IMHO, moot.

IMHO.

Q.

I am not advocating the use of power factor correction for home use.
I am saying that CFLs are advertising false savings.
You are being billed for apperant power useage if you have an old style power meter, I already proved it case closed move on.
Assume you are being billed for apperant power usage unless you can prove other wise.

Hope you keep your mechanical meter, most of them read a slow due to increased friction as they age. When we had all the meters replaced some people got a nasty surprise when they started being charged for what they were actually using..

I thought I'd join in this thread as it was interesting, and I'd never actually given much thought to lights using more power than their rating. So I grabbed the table lamp and took it to our kitchen island, plugged in the Kill-A-Watt meter and started testing. So this is what happened with 3 light bulbs. Bulb 1 was an LED that we had in a can light over the sink, rated at 8 watts, bulb 2 was a spiral CFL from this lamp, rated at 10 watts and bulb 3 was a decorator type enclosed spiral CFL from over the dining room table rated at 14 watts. As the pictures show, my house is at ~120 volts and the wattages all tested good. The part I thought odd was bulb 3. It comes on dim and ramps up slowly to full brilliance and as such it stated at 10w and in about 30 seconds went to 14w. This caused me to go back and retest the other bulbs to make sure they had time to ramp up more if they were going to. They did not. Since pictures are worth 1000 words, here's a few thousand to look at :o

What did the VoltAmps going to those light sources look like?

I guess I don't understand the term VoltAmps. Does showing the house voltage and the wattage not show the consumption accurately? :confused:

I'm not trying to be defensive or argumentative, I just don't understand what it is that you are looking to answer? My knowledge of how electricity works is just too limited to answer this question.

True power and watts are the samething.
Apperant power and VoltAmps are the samething

True power or wattage is when amps and volts consumption happen on the same order of magnatude at the same time.
Since electrical power, alternating current in north America switches directions 120 times a second. In that time voltage at a 120 volt wall socket goes from 0 to 170 to 0 volts each time. And yes you do get 170 volts at a 120v outlet, but you also get 0 volts too.
In a perfect world with a power factor of 1 every time that alternating current going to a device hit the peak voltage the amperage draw would peak in the same instant and go back down at the same rate as the voltage. The amp draw would perfectly follow voltage.
This perfect unity of voltage and current flow only happens in purely resistive loads such as light bulbs and base board heaters.

In a world where you have AC motors, transformers, solid state switching devices somthing rather odd happens. Peak or peaks in current flow start to lag behind the peak in voltage.
This is really bad for a laundry list of reasons.
As the voltage peaks, current being drawn by a device keeps rising, this continued increase in current draw can be happening while the voltage of a cycle is drawing down.
This is when current flow peaks and voltage peaks shift out of line with each other.

This shift is called power factor.

Watts are kind of like a measure of the work your boss sees you do. The VoltAmps are your job plus all the other crap you have to put up with and do to get your job done.
That is about the most easy and least accurate way to breake it down.
I have other comparisons that break watts and voltamps down using drunk loggers or trains pulling traincars.

I tested some LEDs expecting to find a much better power factor.
Eh,,, marginally better.
I caught a 10watt LED using 13.5voltamps.

Any way you cut it the greater than 0.7 power factor is better than the 0.5 to 0.6 power factor CFLs seem to like to run at.

I used to think that LEDs didnt offer enough improvement to warrant their additional cost.
I reverse my position.

I guess that for the discussion of power factors and voltamps, I shall remain blissfully ignorant. I read both your posts twice and it went over my head both times.

I have way too many other things bouncing around inside my head to spend the time to learn what all this really means, but also can respect that it is a matter of interest to you. I will measure a CFL for the voltamps if you can tell me how to do it on my Kill-A-Watt meter and post the results on Monday if nothing terrible happens.

I don't have internet at home, so in about an hour I'll be gone until about 7:30 CST Monday morning.

I have 2 kill-a-watt meters, one thats probably the original version and a newer one. Both work the same way you have the up and down buttons that scroll through the options.
Plug it in and it should default display voltage, normal reading is 115 to 125.
Hz is Hertz, the power frequency, should always read 60 to 59.9 allover north america unless plugged into a generator or 50Hz inverter if you can find one.
Watts are watts, also known as true power.
Amps are the current.
Then you have the 2 weird ones, VoltAmps and power factor displayed as P.F.
You might notice VoltAmps are usually about the same as watts, but not always depending on whats plugged in.
P.F. is always 1 or less and makes no sense to the vast majority of people.

I am a little more intrested in the power factor they run at, just to get an over all idea of how bad their operational charteristics are. But their watt and voltamp readings after they have warmed up and leveled off are just as good.

I'll try it and see what happens

I'm measuring a 10W GE CFL and it shows ~8.8W used. And my new Kill-A-Watt 'Edge" doesn't do PF ... sigh.

I have been using mini-cfl in my house for the last 14yrs. Aprox. 60 total in house.

I don't know why but they don't last nearly as long as they advertize?
Very annoying!

It could be my 8,500' altitude or power line fluxuation or ??

My neighbors say same thing.

My Cree 800 lumen (60W equivalent) warm white, dual bulb frankenlamp settled in twitching back and forth between .90 and .99 on the PF scale of my Kill-a-watt P4400. If I dialed down the dimmer, the PF drove down drastically, but we all know dimmers waste power. With the dimmer on full brightness, the PF seemed to flip-flop between the two readings rhythmically.

I get anywhere from a .49 to a .56 PF on my 3-way CFL bulb, depending on the switch setting. The .49 PF is on the dim setting, the .56 is on the brightest setting.

Positioning effects light output, efficiency and life.
Screwing them into a horizontal base, verticle base up and base pointing down all have their own differences.

I bought two 20w utilitech pro para38 outdoor flood, 1035 lumens. It runs a 0.94 powerfactor.

Checking again last night came up with 47 to 49 on the PF. I was a bit surprised to see those numbers, but I don't yet see any value in knowing the number. Is there a way to improve the number? That was with or without the lamp even being plugged into the meter.

To correct power factor you can do what it appears the LED manufactures have done to at least some of their products.
Add capacitence to the LED circuit.
Or just not buy that particular LED any more. Best way to get LEDs that run a good power factor is to find them on here or buy one and test it. If its got a .5pf, try to return it, if its got <0.9pf then get more of them.
If its more than .5 but not .9, kind of up to you.

Well it appears the CFLs do not have lagging power factor.
Looks like the current is nothing but pure phase distortion, meaning you cant correct the power factor with a capacitor like you can on a motor or welder, adding a capacitor just makes the power factor worse.
Only way I can see to fix this problem is to go with LEDs.