From: Brian Elfert on
"throwitout" <throwitout(a)dodgeit.com> writes:

>The absolute leading edge would be T5s, however there are other
>concerns with them, you must replace the fixtures (different length
>tubes) and the equipment isn't as run of the mill as T8's.

I thought I read somewhere that T5s are actually less efficient than T8
bulbs.

I know that electric utilities are generally no longer offering incentives
to install T8 fixtures in commercial buildings as T8s are the default for
new buildings and remodeling.

Brian Elfert
From: Andrew Gabriel on
In article <13057unke3a6958(a)corp.supernews.com>,
Brian Elfert <belfert(a)visi.com> writes:
> "throwitout" <throwitout(a)dodgeit.com> writes:
>
>>The absolute leading edge would be T5s, however there are other
>>concerns with them, you must replace the fixtures (different length
>>tubes) and the equipment isn't as run of the mill as T8's.
>
> I thought I read somewhere that T5s are actually less efficient than T8
> bulbs.

On electronic control gear, there's no difference.
T8's on magnetic control gear are around 10% less efficient.
(The T5HE and T5HO tubes only run on electronic control gear.)

T5 tubes, having a thinner light source, enables luminaire optics
to be designed to direct the light more accurately, which can mean
less wasted in spillage and reabsorbtion into the tube. This can
make T5 luminaires more efficient even when the tubes themselves
are the same. T5 tubes are still more expensive and tend to have
a rather more limited range of colour temperatures and CRIs
available, so unless the thinner tube size is an advantage to
you, T8's are probably a better choice at the moment.

> I know that electric utilities are generally no longer offering incentives
> to install T8 fixtures in commercial buildings as T8s are the default for
> new buildings and remodeling.

In the UK, T12 luminaires haven't been available for around 25
years now. T12 tubes are available for old luminaires, but they
are low volume products, and many stores no longer stock them.
Almost all our T12 luminaires can take T8 tubes anyway (this is
only true in 230V countries, and not in 120V countries).

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]
From: hob on

"Mick" <mick(a)pal.com> wrote in message news:etrpeg$ofk$1(a)news.datemas.de...
> In old style long fluorescent tubes, you had the tube plus
> the starter & the choke/ballast.
>
> What's happened to the starter & the choke/ballast in the
> current compact models?
>
> Also I had heard that the old style tubes were more
> efficient than regular bulbs. But if you frequently turn
> on & off then they are no longer efficient because the
> starter takes a lot of electricity while starting the light.

While it was ineffecient in many applications, that myth of inefficiency
due to electricity-on-start was debunked long ago -

It was actually the total efficiency considering the cost of labor and
materials for replacing bulb and ballast and switch using the old style
ballasts, bulbs, and switches - in short, the old ballasts and bulbs only
had so many starts in them, not by design, but by typical application and
limits of materials.
I have seen two studies addressing efficieny in fluorescents - One study
had four hours use run time between starts or shut it off, another three
hours for maximum efficiency (not electrical efficiency).

We used the three hour criterion for many years - but wide-spread use of
electronic ballasts and better bulbs have pretty much removed the
"stay-on-time" program for equipment put in in the past decade .
If you hire an electrican to change your old-style ballasts, you are
probably still in that two hour range -- but that leave-it-on-for-efficiency
has a bit more to it.

A fluorescent light can be very inefficient and costly if the total
package is considered in certain applications - e.g., put fluorescents in
your dining room instead of incandescent, and the $5000 fine-wood table
finish embrittles and the color fades in the higher-UV light.
Net energy saving from bulb-to-bulb swap for 5 years - $ 50 a year saved.
Net efficiency over 5 years - $ 50 saved from electricity, $ 5000 lost
due to table damage, net efficiency is a loss of $4950.

Draperies, silk lamp shades, and some plastic shades absolutely also do
not like fluorescent lights, nor does fine art - and many things in
bathrooms are plastic and will yellow in fluorescent light.

Use of those bulbs around that kind of bulb results in a loss far greater
than any savings from a smaller light bill.

> Because of this it was not advised to use these in places
> like toilets etc, where you don't keep them on for long
> periods after turning them on. Is this still true for the
> CFL's?
>
>
>


From: J. B. Wood on
IIn article <ZMKdnXMu2Jg8857bnZ2dnUVZ_rqhnZ2d(a)comcast.com>, "hob"
<dehoberg(a)comcast.net> wrote:
> Draperies, silk lamp shades, and some plastic shades absolutely also do
> not like fluorescent lights, nor does fine art - and many things in
> bathrooms are plastic and will yellow in fluorescent light.
>
Hello, and while I can't comment on the above, I can say the only thing
stopping me from exclusively using fluorescent fixtures in my home is that
my eyes quickly get fatigued while reading under artificial electric light
other than incandescent. Sincerely,

John Wood (Code 5550) e-mail: wood(a)itd.nrl.navy.mil
Naval Research Laboratory
4555 Overlook Avenue, SW
Washington, DC 20375-5337
From: phil-news-nospam on
In alt.engineering.electrical hob <dehoberg(a)comcast.net> wrote:

| A fluorescent light can be very inefficient and costly if the total
| package is considered in certain applications - e.g., put fluorescents in
| your dining room instead of incandescent, and the $5000 fine-wood table
| finish embrittles and the color fades in the higher-UV light.
| Net energy saving from bulb-to-bulb swap for 5 years - $ 50 a year saved.
| Net efficiency over 5 years - $ 50 saved from electricity, $ 5000 lost
| due to table damage, net efficiency is a loss of $4950.
|
| Draperies, silk lamp shades, and some plastic shades absolutely also do
| not like fluorescent lights, nor does fine art - and many things in
| bathrooms are plastic and will yellow in fluorescent light.

I was under the impression that FL light blocked UV down to the level
of IN light. Is this a wrong impression? If so, then maybe we need
to add more UV blocking or restrict these lights more so in certain
places.

--
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