Many (and I would suggest the majority of modern) CFLs operate at a frequency higher than 60Hz. The advantage of this is that it allows the ballast circuitry to be more compact.
Lower frequencies require bulkier inductive components, while higher frequencies allow smaller inductive components to be used. The drive to have a CFL fit within a standard A-lamp form factor requires small ballast components. This has pushed the industry to adopt higher frequency operation in order to make a more compact Compact Fluorescent Lamp.
Other advantages of high frequency operation is that oscillations above 20,000 Hz are typically beyond the range of human hearing, and much faster than the eye can detect, eliminating the annoying humming and flickering common to early fluorescent and compact fluorescent lamps.
These obvious advantages come at a small sacrifice in efficiency, however, as higher frequency operation is generally slightly less efficient than low frequency operation.
Nevertheless, adopting CFLs throughout your home will take a hefty chunk out of your lighting bill.
It is true that excessive heat may reduce the life of a CFL, and this may occur in some enclosed fixtures However, this is extremely unlikely, as CFLs generate very little waste heat, unlike an incandescent.
The big problem in the U.S. marketplace for all modern lighting technologies is that the American consumer is conditioned to think light output is measured by the energy consumed. When you purchase a 100 Watt incandescent light bulb, the 100 watts is the measure of the energy it uses, and not the amount of light it produces. The unit for measuring light output is the Lumen, the SI measurement for Luminous Flux.
That 100 Watt Light Bulb produces about 1750 Lumens of light. However, a good quality 23 Watt CFL produces the same number of lumens while consuming less than 1/4 the electricity. When you consider that lighting is roughly 1/6 of your electric bill, you’ll save about 4-5% each time the electric bill comes in.
This is just the beginning - the rest of those 100 Watts an incandescent uses have to go somewhere, and they do. They radiate as waste heat, which is why incandescents get so hot. This is a particularly bad deal when you are running your air conditioner, using electricity to cool air you are using electricity to heat for light. So the savings stack up, especially in the summer time.
Of course, if you live in Alaska, and electricity is cheap, energy saving lamps may not make as much sense.
I should have realized that the higher frequencies permit smaller inductors. What voltage is put into the tubes? Isn’t that the claim to fame for switching power supplies?
Could you run a fluorescent on DC, say smooth it and then the light would be “on” more of the time?
We have a combination of CFLs and incandescents. Our table lamps with 150 watt bulbs don’t do well with a CFL.
How do you see LED lights as compared to CFLs for general lighting. Looking through the hype, are their problems with getting white light from LEDS that will be very difficult to overcome?