The latest NEMA numbers for CFL sales indicate significant success. Unfortunately, the press release doesn't do the numbers for the press, and the press and public are innumerate. So they are interpreting the numbers as indicating problems.
The past three years have shown CFL sales at 28, 20, and 24% of total bulb sales. This is after a fairly rapid ramp up from a few percent. This indicates a huge success, but that is obscured by the difference in bulb lifespan.Consider a steady state situation where half the use is CFL and half the use is incandescents. CFL's last 8 times longer than incandescents. So for every CFL that needs replacing, there will be eight incandescent replacements. That's an 11% market share for CFLs. The following matrix shows the bulb sales share for different steady state situations, with both a five and eight times life (because for several years there were quality problems with some of the CFL makers).
|Market penetration||5* Longer||8* Longer|
If the present situation is steady state, the current sales percentage would mean 60 to 75% of installed bulb usage is CFLs. If lifespan is 8 times longer and current installed bulb usage is 50%, then installed usage increased by 13% last year to 63%. Either way these numbers indicate a substantial success for CFLs.
(This analysis does not incorporate the lag effect from longer life. CFLs sold this year will not need replacement for several years, which means that each sale that replaces an incandescent means no bulb sale at all for a few years. This will also cause a temporary dip in CFL sales as they replace the incandescents but don't yet need replacement themselves.)