Ball park lighting figures?

[CWatters]

I know there are a lot of variables but could someone point me to ball park
figures for various lighting technologies?

For example manufacturers (optimistically?) claim an 11W flourescent lamp
produces about the same amount of light as a 60W incandescent.

What about LED lamps that are now becoming available? How do they compare?
Would a 4.5W output LED be bright enough for use as a ceiling mounted
downlighter in a kitchen etc

Anyone know of some good sources for LED based lamps for use in buildings?

Thanks

 

[CWatters]

"Watson A.Name - "Watt Sun, the Dark Remover"" <NOSPAM@dslextreme.com> wrote
in message news:10r06q3s68am914@corp.supernews.com...

He should've thoroughly read Don Klipstein's Lighting FAQ and ancillary
documents, LEDs, Compact Fluos, etc. before asking here. He would not
have had to ask here at all, then. http://members.misty.com/don/

Thanks that site has more info I was looking for.

I was wondering if LEDs met the UK Buildings Regulations (Part L) but it
seems not quite as the spec they need to achieve 40 Lumens per Watt.

 

[Don Klipstein]

In article <pxCrd.7290$6W2.398449@phobos.telenet-ops.be>, CWatters wrote:

I know there are a lot of variables but could someone point me to ball park
figures for various lighting technologies?

For example manufacturers (optimistically?) claim an 11W flourescent lamp
produces about the same amount of light as a 60W incandescent.

Roughly, roughly, a compact fluorescent lamp produces as much light as
an incandescent lamp of 3-4 times as much wattage. Good compact
fluorescents normally produce 4 times as much light as good incandescents,
except compact fluorescents can be dimmed by non-ideal temperatures, heat
buildup in fixtures, etc.
Another thing - if you put a compact fluorescent in a fixture designed
for an incandescent, the light may not be distributed in a less favorable
manner than that of the incandescent.

Please check out my compact fluorescent stuff at:

http://www.misty.com/~don/cfx.html

"Standard" fluorescents of the more usual "shades of white", especially
the 4 foot T8 (1 inch diameter) ones, are a little more efficient than
compact fluorescents.

One more thing: Fluorescent lamps and incandescent lamps can vary
significantly in efficiency with manufacturer and model due to various
issues of design and quality.

For example, in the USA a "standard" 100 watt incandescent lamp by one
of the "Big Three" makers produces 1710 lumens, sometimes claimed as high
as 1730 or 1750. I see off-brand 100 watt incandescents in packages
claiming as low as 1100 lumens, claimed life expectancy not exceeding that
of longer-life "Big Three" 100W lamps claimed over 1600 lumens, and I
don't only see such junkers in dollar stores.

Compact fluorescents with magnetic ballasts are usually less efficient
than ones with electronic ballasts and they also have quality issues.

Non-compact fluorescents also suffer from ballast issues. Also, ones
with color rendering index higher than 86 or so have less photometric
output than most usual ones with rated color rendering index in the range
of 53 to 86.

What about LED lamps that are now becoming available? How do they compare?
Would a 4.5W output LED be bright enough for use as a ceiling mounted
downlighter in a kitchen etc

The best available white LEDs have typical overall luminous efficacy
around 1.5 to 2 times that of most home-illumination-purpose
incandescents, assuming you have no losses in any ballast/driver
circuitry.

There are some problems:

1. LEDs are extremely expensive for their light output. 5 watt LEDs cost
quite a few $$. I just checked out Quickar Electronics, which is a place
to get just one or a few, and I just saw a price for a 5 watt white one at
about $30.
Time for that to be paid back by electricity savings over a 15 watt
incandescent, assuming electricity cost of 10 cents per KWH (roughly the
USA national average): 30,000 operating hours. Don't forget the cost of
the ballast or driver circuitry even if you can get a better price on the
LED.

1a. White LEDs do not last forever. Higher figures that I do not know
to be dishonest or wrong for claimed life expectancy are 50,000 hours. It
is easy to get a fraction of that. The main problem is that the usual
white LEDs have a phosphor that wears out during use. This will
exacerbate the economic disadvantage of using LEDs of late 2004
state-of-the-art over more usual light sources for home lighting.

2. As Vic Roberts (someone else who you may run into when the subject is
illumination with LEDs) likes to point out, LEDs have another issue:
They vary considerably in light output from one piece to another, even
of the same part number. They also vary a little in voltage drop at a
given current, often and maybe usually without much positive correlation
in light output at a given current. The best minimum guaranteed overall
luminous efficacy for a higher power white LED that I have heard of so far
is about 16.6 lumens per watt, which is just a little higher than that of
most but not all common incandescents. And this requires a rather
optimistic thermal assumption of a heatsink being at 25 degrees C and no
losses in the ballast/driver circuit.

LEDs do have their place already in more specialized lighting
applications such as flashlights and traffic signals. To see how LEDs get
ahead in those applications, please check out this page of mine:

http://www.misty.com/~don/lede.html

Anyone know of some good sources for LED based lamps for use in buildings?

- Don Klipstein (don@misty.com, http://www.misty.com/~don/index.html)

 

[CWatters]

It seems 40 L/W might not be too far away...

http://www.archenergy.com/lrp/products/brochures/2.1_LED_hybrid_brochure.pdf

Quote: The LEDs are expected to meet the California Energy Commission's new
2005 Title 24 requirement of 40 lumens/watt.

 

[Tweetldee]

Look at and compare the lumen output of the various devices. The lumen
output rating should be printed on both the fluorescent and the incandescent
bulbs. That way, you're comparing apples to apples.

--
Dave M
MasonDG44 at comcast dot net (Just subsitute the appropriate characters in
the address)

Never take a laxative and a sleeping pill at the same time!!

"CWatters" <colin.watters@pandoraBOX.be> wrote in message
newsxCrd.7290$6W2.398449@phobos.telenet-ops.be...

I know there are a lot of variables but could someone point me to ball park
figures for various lighting technologies?

For example manufacturers (optimistically?) claim an 11W flourescent lamp
produces about the same amount of light as a 60W incandescent.

What about LED lamps that are now becoming available? How do they compare?
Would a 4.5W output LED be bright enough for use as a ceiling mounted
downlighter in a kitchen etc

Anyone know of some good sources for LED based lamps for use in buildings?

Thanks

 

[Watson A.Name - \"Watt Su]

"Tweetldee" <masondg4499@comcast99.net> wrote in message
news:mhLrd.191531$R05.50993@attbi_s53...

Look at and compare the lumen output of the various devices. The
lumen
output rating should be printed on both the fluorescent and the
incandescent
bulbs. That way, you're comparing apples to apples.

--
Dave M

He should've thoroughly read Don Klipstein's Lighting FAQ and ancillary
documents, LEDs, Compact Fluos, etc. before asking here. He would not
have had to ask here at all, then. http://members.misty.com/don/

"CWatters" <colin.watters@pandoraBOX.be> wrote in message
newsxCrd.7290$6W2.398449@phobos.telenet-ops.be...
I know there are a lot of variables but could someone point me to
ball park
figures for various lighting technologies?

For example manufacturers (optimistically?) claim an 11W flourescent
lamp
produces about the same amount of light as a 60W incandescent.

What about LED lamps that are now becoming available? How do they
compare?
Would a 4.5W output LED be bright enough for use as a ceiling
mounted
downlighter in a kitchen etc

Anyone know of some good sources for LED based lamps for use in
buildings?

Thanks

 

[CWatters]

"Don Klipstein" <don@manx.misty.com> wrote in message
news:slrncr7dc0.jgs.don@manx.misty.com...

Hi Don,

Thanks for the info. I was hoping they might be good enough to replace low
end Halogen downlights but it seems unlikely.

The UK building regs require a certain number of low energy lamps (>40
Lumins per Watt) to be fitted in a new house. CFL downlights exist but small
diameter models are too tall to fit in my ceiling void. The best I've found
fit in a 100mm void but are 160mm diameter overall with a 120mm light
aperture. They look slightly too large.

Cost aside it occured to me that LED's might offer a solution because they
are physically small and can be dimmed easily. Their small size might also
help with sound and fire regs compliance (no need to cut away insulation.

The best minimum guaranteed overall
luminous efficacy for a higher power white LED that I have heard of so far
is about 16.6 lumens per watt.

....so it seems they wouldn't meet the energy efficiency regs yet.

I believe Halide lamps might produce more than 40L/W but I've not done
enough research yet. I read somewhere that they take a long time to warm up
and I don't know if they can be dimmed.

regards

Colin

 

[sparky]

"Don Klipstein" <don@manx.misty.com> wrote in message
news:slrncr7dc0.jgs.don@manx.misty.com...

In article <pxCrd.7290$6W2.398449@phobos.telenet-ops.be>, CWatters wrote:
I know there are a lot of variables but could someone point me to ball
park
figures for various lighting technologies?

For example manufacturers (optimistically?) claim an 11W flourescent lamp
produces about the same amount of light as a 60W incandescent.

Roughly, roughly, a compact fluorescent lamp produces as much light as
an incandescent lamp of 3-4 times as much wattage. Good compact
fluorescents normally produce 4 times as much light as good incandescents,
except compact fluorescents can be dimmed by non-ideal temperatures, heat
buildup in fixtures, etc.
Another thing - if you put a compact fluorescent in a fixture designed
for an incandescent, the light may not be distributed in a less favorable
manner than that of the incandescent.

Please check out my compact fluorescent stuff at:

http://www.misty.com/~don/cfx.html

"Standard" fluorescents of the more usual "shades of white", especially
the 4 foot T8 (1 inch diameter) ones, are a little more efficient than
compact fluorescents.

One more thing: Fluorescent lamps and incandescent lamps can vary
significantly in efficiency with manufacturer and model due to various
issues of design and quality.

For example, in the USA a "standard" 100 watt incandescent lamp by one
of the "Big Three" makers produces 1710 lumens, sometimes claimed as high
as 1730 or 1750. I see off-brand 100 watt incandescents in packages
claiming as low as 1100 lumens, claimed life expectancy not exceeding that
of longer-life "Big Three" 100W lamps claimed over 1600 lumens, and I
don't only see such junkers in dollar stores.

Compact fluorescents with magnetic ballasts are usually less efficient
than ones with electronic ballasts and they also have quality issues.

I have an industrial application where we used compact flourescents. The
magnetic ballasts actually had a much better life expectancy than the
electronic version.

Non-compact fluorescents also suffer from ballast issues. Also, ones
with color rendering index higher than 86 or so have less photometric
output than most usual ones with rated color rendering index in the range
of 53 to 86.

What about LED lamps that are now becoming available? How do they
compare?
Would a 4.5W output LED be bright enough for use as a ceiling mounted
downlighter in a kitchen etc

The best available white LEDs have typical overall luminous efficacy
around 1.5 to 2 times that of most home-illumination-purpose
incandescents, assuming you have no losses in any ballast/driver
circuitry.

There are some problems:

1. LEDs are extremely expensive for their light output. 5 watt LEDs cost
quite a few $$. I just checked out Quickar Electronics, which is a place
to get just one or a few, and I just saw a price for a 5 watt white one at
about $30.
Time for that to be paid back by electricity savings over a 15 watt
incandescent, assuming electricity cost of 10 cents per KWH (roughly the
USA national average): 30,000 operating hours. Don't forget the cost of
the ballast or driver circuitry even if you can get a better price on the
LED.

1a. White LEDs do not last forever. Higher figures that I do not know
to be dishonest or wrong for claimed life expectancy are 50,000 hours. It
is easy to get a fraction of that. The main problem is that the usual
white LEDs have a phosphor that wears out during use. This will
exacerbate the economic disadvantage of using LEDs of late 2004
state-of-the-art over more usual light sources for home lighting.

2. As Vic Roberts (someone else who you may run into when the subject is
illumination with LEDs) likes to point out, LEDs have another issue:
They vary considerably in light output from one piece to another, even
of the same part number. They also vary a little in voltage drop at a
given current, often and maybe usually without much positive correlation
in light output at a given current. The best minimum guaranteed overall
luminous efficacy for a higher power white LED that I have heard of so far
is about 16.6 lumens per watt, which is just a little higher than that of
most but not all common incandescents. And this requires a rather
optimistic thermal assumption of a heatsink being at 25 degrees C and no
losses in the ballast/driver circuit.

LEDs do have their place already in more specialized lighting
applications such as flashlights and traffic signals. To see how LEDs get
ahead in those applications, please check out this page of mine:

http://www.misty.com/~don/lede.html

Anyone know of some good sources for LED based lamps for use in
buildings?

- Don Klipstein (don@misty.com, http://www.misty.com/~don/index.html)