Beginning in 2012, common light bulbs sold in the U.S. will typically use about 25% to 80% less energy. Many bulbs meet these new standards, including incandescents, CFLs, and LEDs, and are already available for purchase today. The newer bulbs provide a wide range of choices in color and brightness, and many of them will last much longer than traditional light bulbs. The lighting standards, which phase in from 2012-2014, do not ban incandescent or any specific bulb type; they say that bulbs need to use about 25% less energy. The bipartisan Energy Independence and Security Act of 2007 (EISA 2007) established these efficiency standards.

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More traditional inefficient 100 watt (W) bulbs—typically incandescent bulbs—will give way to choices—including newer incandescent bulbs—that use only 72 watts or less to provide you a comparable amount of light (lumens). If you are replacing a 100W bulb, a good rule of thumb is to look for a bulb that gives you about 1600 lumens. Your new bulb should provide that level of brightness for no more than 72W, cutting your energy bill.

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So our reactive 25 watt CFL still uses an honest 25 watts, even though amps and volts go out of phase and the sneaky VA rise to 50, making energy consumption appear to double. The extra 25 volt-amperes is not lost or consumed, just stored or borrowed. It goes to work somewhere else. It may offset the power factor of another appliance or it may go back out to the utility line where industrial capacitors tweak it back into phase. Utility meters may not read the extra volt-amperes that CFLs suck into the house, but neither do they read the extra voltamperes that blow back into the grid from Carol’s house. Everything gets canceled out, and the only thing actually consumed is the 25 watts.

So what, you're probably thinking. I have many electronic power supplies running everything from televisions to computers to amateur radio equipment and all have this same peak cycle current draw.

Quite true. I can't find a definitive number in a quick Internet check, but the figures thrown around say that 15-20 percent of electrical power consumption in the US results from lighting and the great majority of this represents incandescent lamps.

If we switch to CFL lamps, the total lighting-related power consumption will drop, a good thing generally. However, having a significant proportion of the total electrical power load represented by AC waveform peak devices such as the Sylvania CFL I looked at is definitely not a good thing. It increases the harmonics in the power line and also presents a highly non-linear load to the power utilities. These things complicate both electrical generation and the distribution network, including power transformers. The European Union, in fact, has adopted a standard, EN61000-3-2, placing limits on the relative amplitude of the current pulse harmonics, with the thought of avoiding or at least reducing problems caused to the electrical power grid by peak-charging loads such as the CFL.

This is sometimes said to be a "power factor" issue. Normally the power factor relates to the phase between the voltage and current waveforms. Power factor is the cosine of the phase difference between the voltage and current, sometimes expressed as a percentage and sometimes as a ratio over the range -1 to +1. A resistive load has a power factor of 1.0, as the voltage and current are in phase. Motors are inductive and have a power factor that varies with motor size and construction, but is usually in the 0.8 to 0.9 range. Overall, a power utility's load is normally inductive due to customer's motor loads, and the power factor can be brought closer to 1.00 with capacitors, if necessary. You will sometimes see a capacitor package installed on pole tops by some utilities for power factor correction. (At the risk of being inaccurate due to brevity, the power generation and distribution network must be sized for apparent power, i.e., VARs or the product of voltage times current, called volt-amperes. The actual load that residential and small business customers pay for, however, is voltage times current times power factor or watts. Hence, it's most efficient for the utility if power factor = 1.00. Large scale industrial and commercial users, however, often are billed for both VARs and kwh.)

The issue with a CFL is not so much the power factor, as it is that the entire power is drawn over a relatively small segment of the 60 Hz waveform. This spike-type current waveform, if analyzed in a Fourier series, or looked at with a spectrum analyzer, will show that it causes harmonics in the power system. It also causes a problem similar to the power factor issue, in that the power network must be designed for the instantaneous voltage/current peaks.