Who knows, a new technology may have come along and no one may be making
them due to lack of a market.
I expect CFLs to advance a little more, especially with gains in dimming
and maybe some models with CRI in the low-mid 90's rather than 82 (with a
compromise in light output).
I expect LEDs to continue their pace of advancement, increment by
increment in performance, cost, and new varieties. But as LED technology
has been incrementing itself along increment by increment, I expect that
to remain the story for the next 10-15 years.
LED technology appears to me to only be advancing about half as fast as
computer technology, maybe a little slower.
There are also metal halide lamps, another technology that has been
advancing somewhat and is still advancing, though not as fast as LEDs are
advancing.
As a result, I expect displacement of incandescents to be a slow and
incremental process that can take another 10-20 years to *mostly*
accomplish. Heck, that process was already underway in the early 1980's,
when most low-voltage-powered front panel indicator lights were LEDs, and
before the mid 1970's those were at least 99% incandescent.
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One area where LEDs (and to some extent in recent years other
technologies) are displacing incandescents is nightlights.
The old traditional model used a 7 watt incandescent, and often a shade
because 7 watt incandescents are rather bright for this job, and it takes
more effort to make an 120V incandescent of wattage much lower than 7
watts - or at least it used to.
Past 15 years or so, 4 watt incandescent nightlight "bulbs" have been
common - still bright enough to usually deserve a shade.
Now, there are many LED night lights available. With ineffeciencies of
safe voltage dropping at low cost, most current models of 120V LED night
lights are not more efficient than incandescents in photometric terms -
but they still achieve efficiency gains by having a spectrum more
favorable to making use of night vision when the lighting is dim (higher
"s/p ratio"), along with being dim enough to not need a shade. Power
consumption of these is mostly around 1/3 watt to 1 watt.
Better are green and blue models and the Feit Electric white C7 "bulb".
Most other LED light models using white LEDs will have light output
degrading significantly year-by-year or even a bit faster.
- Don Klipstein (
[email protected])