While looking for replacement light bulbs (GU10's) I can accross the
option for an LED version of the bulb.

Are there any other LED bulbs around R63's for example?

Has anyone tried LED bulbds and could they comment on their
suitability in a home environment.

Thanks

Phil

"Philip" wrote in message
om...
While looking for replacement light bulbs (GU10's) I can accross the
option for an LED version of the bulb.

Are there any other LED bulbs around R63's for example?

Has anyone tried LED bulbds and could they comment on their
suitability in a home environment.

Thanks

Phil
This site has some MR16 warm white LEDs - they look interesting -
http://www.ultraleds.co.uk/default.php?cPath=50
I have not tried leds for home lighting yet because until recently they were
not really able to compete on light output, light quality and cost.
Now they could be worth considering as they would save power, run cooler and
last far longer than normal bulbs or fluorescents - they may also be useful
for lighting in enclosed spaces where halogens would overheat.
The downside is if they should fail early for any reason, then you lose all
your expected energy savings in the cost of replacements.

Dave

In article ,
logized wrote:
Now they could be worth considering as they would save power, run cooler
and last far longer than normal bulbs or fluorescents

Don't think there's really any difference in efficiency between them and
fluorescents. And high output ones don't last forever either.

--
*How do you tell when you run out of invisible ink? *

Dave Plowman London SW
To e-mail, change noise into sound.

Christian McArdle wrote:
Don't think there's really any difference in efficiency between them and
fluorescents. And high output ones don't last forever either.

They were certainly claiming some advantage over CFL technology. They seemed
to suggest around 7 times greater efficiency, rather than 4-5 times.

This is a flat-out lie.

At the absolute best, using mixed colour LEDs, appropriately picked,
LEDs may put out a little under half the light of fluorescant lights.
(watt for watt)
'White' ones, at best, get about a third, more typically a fifth.

White LEDs are about as efficient as halogen bulbs.

Led lights last a long time and are quite a bit more expensive. However
their light is also very directional so if you wanted a wide beam they would
be no good for you.

Regards John www.a2znorthants.co.uk


"Philip" wrote in message
om...
While looking for replacement light bulbs (GU10's) I can accross the
option for an LED version of the bulb.

Are there any other LED bulbs around R63's for example?

Has anyone tried LED bulbds and could they comment on their
suitability in a home environment.

Thanks

Phil

logized wrote:

The downside is if they should fail early for any reason, then you lose all
your expected energy savings in the cost of replacements.

I noticed a year or so ago that the new buses round here were using
clusters of LEDs for their tail/brake/indicator lights, very good I
thought.

But I have noticed over the past few months that about 1/3 of the
individual LEDs have already blown, seems these ultra bright LEDs are
being pushed too hard, negating the reliability (and corresponding lack
of required maintenance) which was presumably a major factor used to
justify their use? I assume the reduced power consumption compared to
filament lamps is a relatively minor factor given that the alternator is
sucking it's power from the dirty great diesel lump on a bus?

I don't think I've ever seen properly driven LEDs "burn out" anywhere
else, of course the ones from Birkett's I play^H^H^H^Hexperimented with
years ago without using current limiting resistors were a different matter!

On Mon, 22 Nov 2004 17:36:21 -0000, Christian McArdle wrote:

12V Halogen 20W 2000h
(50 bulbs * 0.65 + 1000kWh * 0.06) = 92.50 TCO (+10 quid for
transformer)

230V Halogen 25W 2000h (yea right, more like 1000h!)
(50 bulbs * 1.30 + 1250kWh * 0.06) = 140 TCO

230V CFL 5W 10,000h
(5 bulbs * 10 + 250kWh * 0.06) = 65 TCO

230V LED 3W 50,000h
(1 bulb * 17) + 150kWh * 0.06) = 26 TCO

Is this all for the same lumen level per lamp? CFLs vary immensely for
the same nomimal power...

--
Cheers
Dave. pam is missing e-mail

Andy Burns wrote:


But I have noticed over the past few months that about 1/3 of the
individual LEDs have already blown, seems these ultra bright LEDs are
being pushed too hard, negating the reliability (and corresponding lack
of required maintenance) which was presumably a major factor used to
justify their use? I assume the reduced power consumption compared to
filament lamps is a relatively minor factor given that the alternator is
sucking it's power from the dirty great diesel lump on a bus?

I 'spect you're right about them being overdriven. There's still a win
over single blubs as far as relamping goes, since (as you've observed)
individual LEDs can lose their holy smoke while the rest of the cluster
still gives out useful photons...

In article ,
Malc wrote:
I use LEDs and standard halogen bulbs for caving and I can assure you
that the halogen bulb wins on light output. I suspect that if you had
enough LEDs to match the output of a bulb then there would be precious
little difference in consumption. I only use the LEDs as emergency
backup lighting.

As regards pro lights for filming, they're much more economical on
batteries than halogen for the same light. But much more expensive.

--
*When it rains, why don't sheep shrink? *

Dave Plowman London SW
To e-mail, change noise into sound.

"Philip" wrote in message
om...
While looking for replacement light bulbs (GU10's) I can accross the
option for an LED version of the bulb.

Are there any other LED bulbs around R63's for example?

Has anyone tried LED bulbds and could they comment on their
suitability in a home environment.

Thanks

Phil

I tried 12 LED lamps and they were attrocious, in theory replacements for
halogen spots but a complete waste of time. Light was very poor and had a
blue'ish tinge making it look very cold.

Took them back and got £150 refund!

On 22 Nov 2004 19:05:51 GMT, Ian Stirling
wrote:


At the absolute best, using mixed colour LEDs, appropriately picked,
LEDs may put out a little under half the light of fluorescant lights.
(watt for watt)

This article, http://members.misty.com/don/lede.html was mentioned on
uk.rek.photo.misc recently and has some interesting information.
http://www.cree.com/News/news175.asp is quoting 65 Lumens/Watt for
development models which is close to fluorescent efficiencies.

--
Peter Parry.
http://www.wpp.ltd.uk/

This is what i was looking for:
http://www.exposurelights.com/exposure_spec.htm

The efficiency claims are rather unclear - they're claiming it's a
5watt LED that gives equivalent light to a 32 watt halogen. Then go
on to say that they're only twice as efficient as halogen. Now 5
watts is 5 watts which suggests that they're a)heavily overvolting it
or b) the electronics that drive it are very inefficient and another
10watts is soaked up there.

Peter Parry wrote:
On 22 Nov 2004 19:05:51 GMT, Ian Stirling
wrote:


At the absolute best, using mixed colour LEDs, appropriately picked,
LEDs may put out a little under half the light of fluorescant lights.
(watt for watt)

This article, http://members.misty.com/don/lede.html was mentioned on
uk.rek.photo.misc recently and has some interesting information.
http://www.cree.com/News/news175.asp is quoting 65 Lumens/Watt for
development models which is close to fluorescent efficiencies.

Which are now actually available.
This field has moved on incredibly in the nearly 4 years since this post.

A good 'warm white' high power LED will now put out comparable amounts
of light per watt as a CFL, and if you're willing to accept really nasty
colour rendition, it can rise to nearly as efficient as a linear fluorescant.
(60lm/w, 100lm/w).