CFL lamps and ohm's law

[myredracer]

Have been wondering about this for a while and maybe someone here has the answer.

Looking at a typical 13 watt CFL, if you look at the base, it has the current printed on it. A Philips CFL we have for example, is 220 ma (0.22 amps). If you multiply the current by 120 volts, that's 26.4 watts (or volt-amps to be more correct). That's basically twice the rated wattage of the lamp. That is also an extremely poor power factor.

AFAIK, residential meters do not take power factor into account and they base the KWH readings on amp draw. Or do the new smart meters take power factor into account?

So is the utility company charging us for twice what the rated wattage of a CFL is?

 

[happy2rv]

CFLs are a reactive load. I've never really thought about how power meters work in relation to power factor, but the bottom line is that residential customers should be charged on the "real" power, not the VA. See this article for an explanation.

 

[Ray-CA]

Always like this.....

 

[theoldwizard1]

There is electronic circuitry builtin to the base that replaces the ballast and starter that is in an old fashioned fluorescent light and actually drives the mercury vapor inside the tube.

Wikipedia - Fluorescent lamps