PowerSwitch

I've come across a company called Excled, supplying a wide variety of LED Lightbulbs:
http://www.led-lightbulbs.co.uk/
(including a T8 ‘fluorescent’ tube)

Note: This is not a recommendation as I've not had any dealings with them.

However, they are exhibiting at Energy Solutions Expo @ Olympia in October:
http://www.energy-expo.info/

Very few LED lamps live up to the claims made, though the technology is improving rapidly, and these look better than some.

Replacing standard flourescent lamps with LEDs is seldom worthwhile since flourescent lamps are already a highly efficient long lasting light source.

Replacing incandescent lamps with LEDs is often more worthwhile since incandescent is a low efficiency short life light source.

Replacing very small CFLs with LED can be worth while, but only for CFLs less than about 5 watts at present.

The above post will cause me considerable expense, since I will have to buy a couple to try

I'm a little dubious about a lot of the lamp replacements but LED light sources are developing faster than I would have believed a year ago. We have replacements for Halogen luminaires up to 800 lumens and will be up to 1200 lumens next year. Thats equivalent of around 45W Halogen, not cheap and not a lamp replacement but really the light source is a different technology if you restrict yourself to making something compatible with a twenty year old lamp format you will never get the best out of it.
Already in our business we see focus moving away from low wattage HID lamps (35W and under) and onto LED. At the same time we now have LED source recessed lights eroding sales in the CFL market. It is all change for lighting at the moment. Efficiency is close with these technologies but LED has the advantage of easy and efficient dimming, longer life and from a marketing perspective the mercury free is a nice tagline.
I think the biggest risk at the moment is that we are still stuck thinking about these products as we did conventional light sources. When we can get past this we can really start making the best of the possibilities for the technology.
For information I don't believe for one moment we will save any energy with this, what we save in the short term will be used by lighting designers to make spaces prettier. But in the medium term we have technologies which can really make some significant savings if utility becomes the focus.
Usual disclaimer, these are my opinions not those of my employer, blah, blah, blah.

adam2 wrote:Replacing standard flourescent lamps with LEDs is seldom worthwhile since flourescent lamps are already a highly efficient long lasting light source.

The LED tube replacements I've seen for sale are quite expensive and it's unlikely I can convince our lads to purchase them.

Has anyone any idea how they fare with regards to cost savings over ordinary fluorescent tubes? That is, they're dear to buy but theoretically they should save money for a long, long time.

Take a 600mm tube, for instance. At the moment they're around £35+ and they're treated as a bit of a joke. At what price point does it make it worthwhile buying them?

It would depend of course on the actual light output, and on the actual achieved lifetime.
Both are probably exagerated.

The LED tubes do not emit light in all directions, and the claimed output figures may not take account of this.
In a well designed flourescent light fitting the light emitted in the "wrong" direction is not wasted but is reflected towwards the working area.

Such products are often marketed on the extreme long life, but it must be remembered that the very best flourescent lamps should last nearly 10 years of 24/7 use or about 50 years of domestic use.

IMHO replacing incandescent lamps with flourescent or LED should be higher priority than replacing flourescent with LED for savings that are best small, and may turn out to be illusory.

I just came across this company; http://www.ultraleds.co.uk/ who seem to be cheaper than led-lightbulbs.

I have not used either yet so this is not a recommendation...

I have used the above firm for some years and would certainly recomend them as regards customer service and prices.

As to the qaulity of the goods, most of the items I have purchased have NOT been regular household lightbulbs, so I cant comment on most of those.

I did buy a mains voltage LED wide angle reflector lamp, that has lived up to expectations, but is in limited use at my Mothers home, rather than being subjected to more intensive use, so the durability is unknown.

I have also purchased ultra bright 5mm LEDs in various colours for home made lights and Christmas lights, these were of good qaulity, but are mature technology, not leading edge.

In addition I have purchased LED retrofit lamps for Maglight and other flashlights, these are very impressive indeed, but be warned that they cost more than the flashlight !

Hi Adam

Which firm is it that you have been using?

Thanks

Sam

sam_uk wrote:Hi Adam

Which firm is it that you have been using?

Thanks

Sam

This one
http://www.ultraleds.co.uk/

I've used ultraleds and they're very quick at dispatching goods; not very quick at answering queries. In fact, I've had several e-mails totally ignored.

I have obtained 3 of these LED candle lamps

http://www.nationallampsandcomponents.c ... lbs/29/519

For testing. Two are in use in my local pub, lit for about 18 hours a day, and the other one is stored unused except for brief testing.
After a few months use, I will compare the unused lamp with the 2 used ones in order to see if they have dimmed much, as many do.

Initial impressions are favourable, with light output being subjectivly eqaul to a well used 7 watt CFL or a new 5 watt one.
The lamps are the same shape and style as an incandescent candle lamp, but smaller than most.

Update re my post above.
The LED candle lamps have now been in use for about 8 months, or several thousand hours.
When compared to a virtualy unused example they have become very slightly dimmer, and changed colour very slightly.
The difference is however minute and would not be noticed without a side by side comparison.
I would thouroughly recomend this product, especialy for decorative lighting.

I have since installed about 20 of these at my mothers home. I have replaced a number of single wall bracket lamps with double ones equiped with these bulbs.

Another update, re long term testing of the LED candle lamps.

The original lamps installed a pub are still working fine after about 18 months use, perhaps nearly 10,000 hours.
Very slightly dimmer and a slightly different colour, but not noticable without a side by side comparison.

Unfortunatly it would appear that the qaulity of these lamps has not been maintained in recent production.
Apparently identical lamps purchased less than a year ago have now failed. Used every night from dusk until bedtime, perhaps about 2,000 hours use in nearly a year.
Although the lamps still light, the light output is less than a third of that produced by a new lamp. I would consider that to be a failure.

They were used in well ventilated wall bracket fittings, supplied from the mains normally but with limited use from a UPS during power cuts.
Similar lamps used elswhere seem OK but they are much less used.

I've just bought one of these: http://www.DODGY TAX AVOIDERS.co.uk/E27-Bulb-Daylig ... 52&sr=1-14

Got it this morning and was very impressed at the light output, perfect for reading. Bulb quite large and heavy but OK. Then, with the light on, I plugged in my netbook but it couldn't find any boot device. This happens very rarely, last time was several months ago. I turned off the led bulb and the netbook booted normally.
Was this just a coincidence or do these bulbs emit enough EM radiation to interfere with electronic devices? Is it safe having it just a foot away from my head?

I would be suprised if any harmfull EM radiation is emitted, but have no hard facts in support of this view.

Have you repeated the experiment to see if the intference was real, or a coincidence ?