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Re: Anyone moved to LED Lighting?



In article <4b3e0f59.14524968@xxxxxxxxxxxxx>, Dave Houston wrote:
>don@xxxxxxxxxxxxxx (Don Klipstein) wrote:
>
>>In article <4b3bf8e7.53435281@xxxxxxxxxxxxx>, Dave Houston wrote:
>>>
>>>Rod Elliot has a section on Power Factor and CFLs which appears to indicate
>>>it's a much bigger problem in terms of generator fuel consumption.
>>>
>>>     http://sound.westhost.com/articles/incandescent.htm#pf
>>
>>  Since most grid electricity has generator winding, transmission and
>>distribution losses totalling much less than power delivered, reducing
>>watts reduces generator load and fuel consumption even if the amps stays
>>the same.
>>
>>  Meanwhile, the article did say that a 15W CFL (which typically replaces
>>a 60 watt incandescent) typically takes 29 VA (volt-amps) - total VA,
>>not just VA other than watts.
>
>I have never argued that CFLs do not save energy, merely that they do not
>save as much energy as proponents usually claim. Lumens per watt does not
>account for PF issues

  A 15 watt CFL presents generator net torque load somewhere between 29/60
and 15/60 as much as a 60 watt incandescent does.  Given the usual extent
of losses for power for USA natiobnwide average after it has made it into
the generator mechanical power input shaft, I would say closer to 15/60
than to 29/60, but still in-between.

> (nor THD if its not included in PF calculation).

  It is.  The usual low-power-factor electronic-ballast CFLs have little
lead, no lag - it's mainly harmonic content detracting from PF.  (The H
in THD is "harmonic" - THD is Total Harmonic Distortion which has its own
measurements, although power factor determinations for CFLs do give proper
consideration to harmonic content in the currentwaveform.)

> What I said was that some (not all) of the savings attributed to CFL are
>imaginary. Congress should have mandated minimum standards for PF and THD.

  With even low power factor CFLs having somewhere between 15/60 and 29/60
as much load on gnerators as incandescents do, I would prioritize getting
CFLs utilized, optimize them afterwards.

>Wikipedia has a good explanation of PF.

<SNIP stuff about power factor that I do not find fault with>

>Often, the claims made by CFL/LED proponents are preposterous. I've seen
>numerous articles in main stream media (e.g. NYT) and elsewhere claim that
>switching to CFLs will reduce total energy requirements by 20-25%. We
>couldn't achieve half of that even if we turned off all lights in every
>sector.

  It appears to me that the total is not of global or nationwide energy
usage, but some subset thereof.

> Since nearly all of the savings have to come in the residential
>sector we'll be doing quite well if we get a 1% reduction in total energy.

  Heck, that must be at least 2% of electrical power generation - good for
downscaling the construction schedule of coal-fired power plants by a few.

  That appears to me to still be significant, especially when combined
with the dozen or two other ways to nibble down energy consumption by
siimilar extent and the few ways to achieve even greater energy savings.

>Disparities greater than an order of magnitude cannot be attributed to
>errors in calculation but can only be due to deliberate distortion and
>propagana.

<I snip from here due to point turning>

 - Don Klipstein (don@xxxxxxxxx)


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