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From: John De Armond
Newsgroups: rec.outdoors.rv-travel
Subject: Re: LED light results -- short
Date: Thu, 30 Mar 2006 15:25:46 -0500
Message-ID: <>

On Thu, 30 Mar 2006 06:54:43 -0800, "Dusty"
<> wrote:

>"Neon John" <> wrote in message
>> Actually, LEDs are a poor way to go for boondocking.  They're only
>> a
>> little more efficient than incandescents.
>Huh?  "Neon John", this flies against everything I thought I knew
>about LED's.  I've done the math...and I don't follow you.  Could
>you please elucidate?

Sure.  Here's a table that I put together from published
manufacturer's data about a year ago:

Lighting efficiencies - Initial lumens per watt.  Conventional
ballasts where applicable.

High pressure sodium--                  approx 125 lumens/watt (Osram)
Low pressure sodium--                   150-180 lumens/watt
HID--                                   80 to 110 lumens/watt*
Automotive D2S 35 watt HID              91 lumens/watt
Solarc low wattage HID                  45-60 lumens/watt
32 watt T8 fluorescent--		85 to 95 lumens/watt
standard F40T12--			60-65 lumens/watt
compact fluorescents--			low 30's to low 60's lumens
					per watt, usually 48-60
Sulfur lamp--                           53 lumens/watt
Tri-phosphor neon-type cold cathode--   60-80 lumens/watt
T3 tubular halogen--			20 lumens/watt
white LED--				15-19 lumens/watt
standard 100 watt incandescent--	17 lumens/watt
incandescent night light bulb (7w)--	6 lumens/watt
incandescent flashlight bulbs--		less than 6 lumens/watt

* HID lamps and ballast designs vary widely.

I put this chart together to use in countering the outright lies that
some LED sign suppliers are telling to try to compete with neon.
Unfortunately LED vendors, even some otherwise reputable ones, are
simply lying about efficiency.

Another issue seldom mentioned for LEDs, particularly the high power
and phosphor-based ones, is the dimming curve.  High power and
phosphor LEDs are not like those "last forever" low power LEDs in
calculators and pilot lights and such.  According to the ISA
(International Sign Association - neutral as far as lighting
technology goes), some LEDs are down to half the initial output in as
little as 1000 hours.  Few go beyond 7-8khours to half output.

Since I put this chart together, LEDs have gotten a little better,
phosphor-free Tri-Die white LEDs have come to market, CFLs have
improved a bit, CCFLs have come along and low pressure sodium lamps
with better color rendering but with about the same efficiency have
become commonly available.  Still this chart is highly representative.

You'll notice that any of the fluorescents are many times better than
LEDs and that LEDs are on par with medium sized and larger
quartz-halogen incandescents.  Only in the small sizes where envelope
and filament holder quench greatly affects the incandescent's
efficiency are LEDs superior.  For general area lighting, LEDs are
pigs - about equivalent to halogens.

If you want a point-source of light, say, a reading light or to
illuminate a spot outside at your campsite, you'd be better off
efficiency-wise with one of the SolArc small HIDs.  Here is a nice
little 13 watt unit, the first item on this page:

I have two of these lights.  One, with the spot reflector, is the
headlight on my electric scooter.  The second, with the flood beam
replaced a 55 watt halogen lamp as my reading and general campsite
light.  It provides enough light for general activities throughout my
entire rig.

For all other types of lighting, inverter-driven CFLs provide the best
bang for the buck.  12 volt versions are available but they're not
worth the extra money, considering how cheap small inverters are now.
After I get some of the CCFLs to evaluate, I suspect that I'll be
recommending them instead of CFLs for RV use.

>> The way to go for low power is with fluorescents.  Especially the
>> compact fluorescents because the rare earth tri-phosphors they use
>> are
>> more efficient than the old halo-phosphates that most conventional
>> fluorescent lamps still use.

>Yeah.  They are better than incandescents.  But only by a rather
>small percentage when compared to the LED's that I knew...

Oh, just a factor of 3 or better.


From: John De Armond
Subject: Re: CF recommendations
Date: Sun, 25 Jun 2006 11:52:50 -0400
Message-ID: <>

On 25 Jun 2006 06:48:22 -0700, wrote:

>Barry wrote:
>> Thought this group might have some useful info.  I have replaced the 17 65w
>> bulbs in our basement exercise room with Compact Flourescent.  They are the
>> Indoor flood type bulbs.  I love how bright they are and use little energy.
>> Unfortunately, I bought them in cheap packages of 5 from Home Depot.  The
>> problem is that they take about 2 minutes to warm up and are very dim when
>> first turned on.  Does anyone have any info on good quality CF indoor floods
>> that turn on instantly that I could use to replace them?  I often go into
>> the room for just a moment and it is frustrating how dark the room is.
>> Thanks
>> Barry
>Have you ever thought about using the white light LED-based
>light fixtures? They are more efficent than incandescents
>and very energy efficent.

No they're not.  Ordinary incandescents and white LEDs are about
equivalent.  Quartz-halogen lamps actually beat LEDs by a bit.  Only
in the very small sizes, flashlight and below, do LEDs have a decided
advantage and that is only because small incandescents are so much
LESS efficient because of wall and filament mount quenching effects.

Here is a table of efficacies that I compiled about a year ago
(nothing has changed enough to matter since then):

Initial lumens per watt

High pressure sodium--                  approx 125  (Osram)
Low pressure sodium--                   150-180
HID--                                   80 to 110 *
Automotive D2S 35 watt HID              91
Solarc low wattage HID                  45-60
32 watt T8 fluorescent--		85 to 95
standard F40T12--			60-65
Tri-phosphor neon-type cold cathode--   60-80 **
compact fluorescents--			low 30's to low 60's,
                                        usually 48-60
Sulfur lamp--                           53
T3 tubular halogen--			20
white LED--				15-19
standard 100 watt incandescent--	17
incandescent night light bulb (7w)--	6
incandescent flashlight bulbs--		less than 6

* HID lamps and ballast designs vary widely.
** dependent on transformer type and efficiency


From: John De Armond
Subject: Re: CF recommendations
Date: Mon, 26 Jun 2006 16:44:04 -0400
Message-ID: <>

On 25 Jun 2006 21:28:12 -0700, wrote:

>In the folllowing webpage that I had previously posted
>if you click on "details and specifications"
>a table will appear, the vendor indicating that this
>white light  36 LED 1.3 watt bulb outputs 60 lumen.
>at 46.15 lumen/watt
>and  at
>the vendor says this  36 LED 3.0 watt light bulb
>(LYPCB06 CW) outputs 90  lumen/ 3.0 watts
>at  30 lumen/watt.

Oops, sorry, I forgot that there are people out there who still
believe advertising claims.  The LED lighting industry is only
slightly better than used car salesmen in their lies.

Being in the sign business where all types of lighting are used and
where a f*ck-up is glaringly visible and financially costly, I don't
believe advertising claims.  I do believe independent testing from
credible third parties such as testing labs, NIST, etc., which is
where my numbers came from.

LED peddlers stormed the sign biz a few years ago claiming to obsolete
all other forms of lighting.  Something went wrong on the way to
nirvana.  They lied.  We quickly learned that the efficacy and
lifetime figures were numbers that they essentially pulled from their
*sses.  Even the vaunted Nisha white LEDs would be down to below half
their initial brightness after as little as a year of 20/7 operation.
Blue LEDs followed closely, followed by green and yellow.  Red ones
maintain brightness fairly well but only if under-driven
significantly.  And by the time enough LEDs are packed into a sign to
actually equal the brightness of neon, other cold cathode,
fluorescents, HID, etc., both the power consumption and heat
production is way out of line with what they're supposed to replace.

Even though I make neon, I'm not wedded to it.  If something better
ever does come along I'll gladly use it instead.  But I base my
decision (and by implication, my business) on independently developed
data from credible sources and not advertising claims, no matter how
they're re-packaged, and that goes for Wikipedia as well.

It should be evident to all but the most dense that places like and others are simply parroting numbers supplied by
others. Of course, since you're just slinging BS on the net you can
believe anyone you like.

For everyone else, I suggest looking to credible independent sources.
Illuminating Engineering Society of North America, International Sign
Association, NREL, NIST, etc.  Yeah, you usually have to be a member
and/or pay for the data but that's life.


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