LED V CFL.

I visited this subject 12 or 18 months ago Ian, and found much the same
as you.

LEDs for general lighting are over priced, under powered, and need a lot
of development before they are in the same ball park. The colour output
is horrible for general use as well.

A friend of mine got some 12 Volt units to replace his power hungry down
lights, and found they were great for this purpose. They are running
nice and cool, compared to the little radiators he was running beforehand.

Cheers Don...

=======================

Last year I scrounged a couple of 3-bulb light fittings on freecycle, once
my flat has been refurbed so I can put them up its a chance to try out
various mixes of LED/CFL - but not before the price has fallen a fair bit
further.

Remember it's an international internet , 240v/led's for sale locally @
$27.00 cost $9us direct from the distributor , it cost us about $100.00
to equip our house , still not cheap but cutting the middle sales greed
saves 60% or better

**Probably. My local supplier has Cree 10 Watt, mains operated (85 VRMS
~ 265VRMS) GU10 MR16 lamps, rated at 750 Lumen (for neutral white and
cool white) and 560 Lumen for warm white, at $42.57 in one off
quantities. 10 off quantities, the price falls to $38.31. Better prices
could likely be found without much difficulty.



**There are CFLs and CFLs. Some are shockers and some are quite decent.
All the ones I use have lasted extremely well and exhibit a pleasing
colour temperature.



**Fair enough. I'm doing likewise, though I've already fitted several
around my home. Reading lamps for my bed were 40 Watt halogens. I've
replaced them with 4.5 Watt LED. The result is that the more focussed
beam is better for my partner (or me) when reading, due to less light
spillover and increased light available on the page. I'm experimenting
with these:

http://www.dealextreme.com/p/12w-3500k-800lm-warm-white-led-emitter-metal-strip-12-14v-80310

Very impressive. Of course, heat sinking must be arranged, along with an
appropriate current source, but the light output is both pleasing and
impressive. At 800ma @ 12 Volts, the light is almost double the
intensity in comparison to an 11 Watt T5 fluoro. Not only directly
beneath the lamp, but also at off-axis positions as well.

Most recently, I acquired one of these:

http://www.dealextreme.com/p/prime-100w-8000lm-led-emitter-metal-plate-pure-white-42806

When I have time, I'll take some comparative photos and measurements
beside a 500 Watt halogen flood (yes, it is that impressive). I'm
presently experimenting with suitable heat sinks. An AMD Athlon heat
sink looks about right.

http://www.dealextreme.com/p/12w-3500k-800lm-warm-white-led-emitter-metal-strip-12-14v-80310


I'm also experimenting with those strips. I have a situation with some
wall lamps with two 18W Philips fluoros and an electronic ballast in a
stainless steel enclosure with a frosted glass panel on top and bottom
(up/down lamps on the wall of a stairwell).
I have 3 of these and every one of them popped the e-ballast due to
overheating after being left on for 3-5 hours a day over a 3 moonth
period. The supplier sent out a sparky and replaced the ballasts but
they are still overheating. It's simply a very poor design since the
e-ballast is fitted inside a steel box with no ventilation and reaches
over 80C.
So I plan to strip the insides out, use a 12V SMPS where the e-ballast
was (same size), adding a few vent holes, and mount one of these LED
strip lights where the fluoro lamps were (one top, one bottom) bolted to
the internal steel enclosure. They easily put out the same amount of
light at 12V 400mA as the 18W fluoro. I took temperature measurements of
the original fitting and will write up some details about the retrofit
and re-measure the temperatures to see the difference.

http://www.dealextreme.com/p/12w-3500k-800lm-warm-white-led-emitter-metal-strip-12-14v-80310


A quick writeup of the tests and results here:
http://www.axtsystems.com/index.php?option=com_content&view=article&id88%%3Aradiathermal&catid48%%3Afixingstuff&Itemid81 %

http://www.dealextreme.com/p/12w-3500k-800lm-warm-white-led-emitter-metal-strip-12-14v-80310

http://www.axtsystems.com/index.php?option=com_content&view=article&id88%%3Aradiathermal&catid48%%3Afixingstuff&Itemid81 %


**Interesting. In the sense that it is an appallingly bad design.
Excellent write-up. It will be interesting to see what transpires. I
just glued some strips to the granite under-bench in the kitchen. NO
problems all Summer.

I just tried those 100 Watt LEDs. WOW! Impressive. With no reflector, it
delivered a little more light than a 500 Watt halogen worklight (which
has a reflector). Next, I'm putting a lens on the sucker to narrow the
beam to 10 degrees.

At various times over the past few years some supermarkets have special
offered CFLs at silly prices - one store even outed a few pallets of 11W
CFLs at only 10p each.

The best SO I can remember for any CFL worth buying was Morrisons did
Philips 18W at 99p - after a few days of not all that many shifting, they
introduced a BOGOF offer at 99p.

I fear it'll be some time before LED prices get anywhere near that
ballpark - lets hope the efficiency improves a bit by then.

**LED efficiency (for even medium quality devices) already exceeds that
of CFLs. The drive is now to reduce costs.

3x 9W 450lumen LED units to equal the light output of an 18W CFL doesn't
sound more efficient to me!

Researchers at a UK university claim to have made a huge breakthrough in LED
manufacturing technology that should slash prices - but expect a wait of 3
to 5 yrs before we see any evidence of that on supermarket shelves.

**The Philips Genie 18WWWB22 is rated at 61 Lm/W.
The Cree LMH2 is rated at 80Lm/W.



**I suspect it will happen a little more quickly than that. Prices have
already fallen significantly in the laast few years. We'll see.

IT will happen, look at the incredible drops in cost of every other
electronic device in the consumer market

I can only compare the lumen outputs of the LED & CFL lamps I found side by
side on the supermarket shelf.

Assuming they get the efficiency better than a CFL - there's always plenty
of greedy suits to carry on cashing in for a while longer!