| Re: Do not feed the Dinosaur!
Eeyore <rabbitsfriendsandrelations@hotmail.com> writes:
> donquijote1954 wrote:
>
> > A typical 25 watt fluorescent light
> > bulb, which replaces a 100 watt incandescent bulb, will last 8 hours
> > on 200 watts worth of power. LEDs (light emitting diodes) are even
> > more efficient and will last days on 200 watts worth of power."
Let me suggest a basic physics course, where the difference between
power and energy will be explained. :-)
> No, LEDs are *not* more efficient.
Right now, they are not more efficienct than fluorescent bulbs, but
that may change as the efficiency of LEDs is being continually
improved. The lastest technology (there are prototypes only at
this point) is comparable to fluorescent lighting.
Also, see <http://en.wikipedia.org/wiki/LED>:
LEDs are moderately efficient; the average commercial SSL
currently outputs 32 lumens per watt (lm/W), and new
technologies promise to deliver up to 80 lm/W. The long
lifetime of LEDs make SSL very attractive. They are also more
mechanically robust than incandescent light bulbs and
fluorescent tubes.
Also,
Due to their monochromatic nature, LED lights have great power
advantages over white lights when a specific color is
required. Unlike traditional white lights, the LED does not
need a coating or diffuser that can absorb much of the emitted
light. LED lights are inherently colored, and are available in
a wide range of colors. One of the most recently introduced
colors is the emerald green (bluish green, about 500 nm) that
meets the legal requirements for traffic signals and
navigation lights.
There are applications that specifically require light without
any blue component. Examples are photographic darkroom safe
lights, illumination in laboratories where certain
photo-sensitive chemicals are used, and situations where dark
adaptation (night vision) must be preserved, such as ****pit
and bridge illumination, observatories, etc.
>
> Nor will most humans be able to generate a continuous 200W. That's
> 1/4 horse power FFS !
>
> If that's their sales spiel then I don't think much of them.
He probably meant 200 watt-hours or something: otherwise you can't
explain why he would say it is enough to last for days.
--
My real name backwards: nemuaZ lliB
|