CFL performance is in the design
My experience with CFLs started 10 years ago when the local power company ran a promotion: get up to nine CFLs for $3 each. I took the offer for the maximum nine lamps. These were the slow-starting variety and were rather long with only one fold. I've been impressed with their performance. I still have seven that are still working. I accidently broke the other two.
Here is where my story goes sour. Every CFL I have purchased in the last four years has failed at 6 months or less. I know they don't like heat but that does not explain all of my failures. Also the myth that on/off cycling is to blame is just that, a myth. Some of original lamps have been cycled thousands of times with no failures. My observation is that the failures are due to cheap components pushed right up to their limits. Another observation is that throwing these things out every six months and replacing them may negate any energy savings.
I have yet to purchase any of the expensive experimental LED lamps. A friend who did is willing to sell it to me at a huge discount. It seems the light output is just not as bright as the equivalent incandescent. My fear with LED lamps is that they are electronic and will fail too quickly due to cheap designs.
Martin Porubcan
Inrush current just not that high
In a letter in your May/June 2011 issue, a reader states that a 100-W incandescent light bulb has an inrush current equal to the steady-state current of a 1,000-W incandescent light bulb. This simply is not true. That level of inrush is typically seen in loads with high impedance but low resistance, such as motors with across-the-line starting so there is no starter to reduce inrush current. Light bulbs have low impedances and high resistances and therefore no significant inrush current. If the reader were correct, coordinating fuses for something like theatrical stage lighting would be difficult due to the millions of watts surging overhead every time the stage lights changed.
David Muratore
Just the fact, sir.
I enjoyed reading your recent article, (An evolutionary water heater, March 1). One thing, however, that doesn't seem to befit a technical article such as this is your reference to macro evolution as though it were fact. The theories of macro evolution, and especially “punctuated equilibrium”, are being questioned by more and more scientists, and clearly are far from accepted scientific fact. I think you would do your readers a service, when referring to macro evolution, to frame it as a theory rather than wording it as fact.
John Darjany
I agree with you, macro-evolution is a theory, not a fact. But like the theory of relativity and gravitation, no one can prove these ideas. I would assert they explain the facts better than anything else humanity has been able to come up with. That doesn't mean they're proven, for sure. People are free to reach their own conclusions.
Rich Crouton
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