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Naughty Nigel
12th January 2016, 06:04 PM
Am I the only one to dislike energy efficient light bulbs?

They may save energy but I find they make reading difficult, and I suspect will leave a legacy of millions with impaired eyesight. Compact fluorescent lamps (CFL's) also contain mercury, which is poisonous, and much more harmful to humans than CO2.

LED's are much better, but they are highly directional and like CFL's rely on electronic control circuits which are themselves polluting and must be disposed of when the lamp fails.

We use quite a few energy saving halogen bulbs at home which save about 30% in energy but provide a clean, white light that is good for reading and close work. These work by reflecting some of the infra red energy back at the filament to reduce the amount of electricity needed to maintain its temperature. However, efficiency is much lower than LED's.

I was therefore fascinated to read this BBC Science report (http://www.bbc.co.uk/news/science-environment-35284112) which claims that by developing this technique Thomas Edison's lighbulb could make a comeback with efficiencies three or four times better than the best CFL and LED lamps, without any flickering or warm up time.

These might also be good for photography. :)

Petrochemist
12th January 2016, 07:12 PM
CFLs are pretty awful IMO.
LEDs are used in energy efficient lightbulbs, and the set in here light the whole room very well.

Halogen lights are hotter than standard Tungsten lights, so emit a greater proportion of visible light (read up on Black body radiation) they still emit a HUGE amount of IR, which is quite wasteful compared to LEDs which also last significantly longer..

From the description it sounds like its basically fitting a hot mirror (as fitted in front of digital camera sensors) around the filament, preventing the loss of heat & keeping the lamp hot & emitting energy.

LEDs these days aren't bad for photography as they use a phosphor to ensure broad spectrum white light is emitted unlike the original versions that had very spiky spectra. They don't work too well for IR photography though...

They claim a theoretical 40% efficiency but currently only manage about half what they quote for CFL/LED types. But LED technologies are not yet near their max theoretical efficiency either. I'm pretty sure some of the claims I've seen for LEDs predict efficiencies over 70% being possible.

Bikie John
12th January 2016, 07:42 PM
What I hated about CFLs was that their brightness was overstated. 18W bulbs are sold as equivalent to 100W old-school incandescents, and they plainly aren't. I reckon (from subjective experience and backed up with various exposure meters - of course) that you need a 30W CFL to replace a 100W filament - and they are much harder to find, much bigger and much more expensive. And hard to dispose of legitimately.

I just got a LED bulb which claims to be 60W equivalent, and subjectively I think that estimate is realistic. Again the problem is that I haven't yet found a 100W equivalent. With my rather poor eyesight I use 100W bulbs because that's how much light I need to read without straining.

It seems that hot wire, while it may be inefficient, is one of the most effective ways of turning electricity into light. So new tech in this area could be really promising.

John

Westy
12th January 2016, 07:51 PM
I have replaced all the bulbs in our house over the past 18 months with led bulbs. They have proven to be a great success, saving electric and in that time not one bulb has blown. A win win in my book. *chr

Petrochemist
12th January 2016, 07:58 PM
What I hated about CFLs was that their brightness was overstated. 18W bulbs are sold as equivalent to 100W old-school incandescents, and they plainly aren't. I reckon (from subjective experience and backed up with various exposure meters - of course) that you need a 30W CFL to replace a 100W filament - and they are much harder to find, much bigger and much more expensive. And hard to dispose of legitimately.

I just got a LED bulb which claims to be 60W equivalent, and subjectively I think that estimate is realistic. Again the problem is that I haven't yet found a 100W equivalent. With my rather poor eyesight I use 100W bulbs because that's how much light I need to read without straining.

It seems that hot wire, while it may be inefficient, is one of the most effective ways of turning electricity into light. So new tech in this area could be really promising.

John

CFLs give less light (& tale longer to warm up) as they get older. I don't plan getting any more of them!

For reading I have a LED desk lamp by my bed. It can safely lie on the bed next to me (even half under the pillow) shining directly on my book without disturbing my wife. Something that would be out of the question with filament lights. Proved very helpful this morning at 04:30!

Zuiko
12th January 2016, 08:06 PM
We bought a job lot of traditional 100W bulbs before they were discontinued and have sufficient for many years to come. I do use energy efficient bulbs in the hall, stairs and landing and in the pantry, where brightness isn't as important and lights are more likely to be left on needlessly.

Naughty Nigel
12th January 2016, 08:36 PM
I just got a LED bulb which claims to be 60W equivalent, and subjectively I think that estimate is realistic. Again the problem is that I haven't yet found a 100W equivalent. With my rather poor eyesight I use 100W bulbs because that's how much light I need to read without straining.

The energy saving halogen lamps do genuinely provide 100 watts worth of light but only use about 70 watts. These have a small halogen capsule inside the normal glass bulb. Being halogen they provide a higher colour temperature than normal incandescent bulbs and last twice as long. Philips also produce a 105 watt bulb which provides 150 watts equivalent light output.

We have quite a few LED lamps around the house now including eight x six watt LED lamps in the kitchen ceiling to replace the old 50 watt halogen lamps fittings. These produce a very bright, crisp light as long as you are directly beneath them, but the beam angle is quite narrow (38), so I have had to fit additional LED lamps above and below the cabinets to fill the shadows!

However, having measured actual power consumption I am somewhat sceptical of the energy savings claimed for LED lamps.

The six watt lamps in our kitchen actually use closer to 10 watts each, (about 9.8 watts), whilst some six watt GU10 replacements also use a similar amount of electricity.

I don't know how the manufacturers calculate power consumption (it should be easy enough), but I suspect the claimed power usage is for the LED's themselves and does not include control gear.

Fluorescent lamps are similar in that only the power consumption of the tubes is quoted. The three 58 watt (5 foot) fluorescent lamps in my garage actually use about 240 watts when running and warmed up!

DerekW
12th January 2016, 11:11 PM
I swapped the external flood lights linear halogen bulbs triggered by PIRs for LED floodlights, the 7 GU10 50watt halogen bulbs in the kitchen all for LED GU10s.

I tracked the power consumption on a frequent basis and I was able to see quite a noticeable drop in the electricity consumption comparing year on year consumption.

Ross the fiddler
12th January 2016, 11:52 PM
I love the latest LED globes with varying degrees of effectiveness but all on the good side though. I've been buying up more as they come out with more designs for more uses, but unfortunately, I also have a stock of fluro globes that I feel compelled to use up, but I think I will be just adding more LED globes & eventually the fluros might get used in some places (maybe). I also have more solar LED garden lights too as they improve. The LED globe I have under the eaves is only 4 watt & produces a lot of light on the deck for what it is. So much so that I have several photos of the possum & baby visiting with it (2m away).

http://fourthirds-user.com/galleries/data/509/OC300361-s.jpg (http://fourthirds-user.com/galleries/showphoto.php/photo/30172)

*chr

Otto
13th January 2016, 09:35 AM
This talk of "wasted" heat from incandescents is erroneous in a cool climate such as ours in the UK. It isn't wasted at all, it allows the central heating to use less fuel!

I hate CFLs so although I do use them in the hallway where the lights are on a lot but the poor quality of the light doesn't matter, for living rooms I still use incandescents for the main light source. I have a couple of table lamps that use LEDs and those work very well. I too bought a good stock of 60W and 100W bulbs before they were phased out.

Jim Ford
13th January 2016, 09:49 AM
I was therefore fascinated to read this BBC Science report (http://www.bbc.co.uk/news/science-environment-35284112) which claims that by developing this technique Thomas Edison's lighbulb could make a comeback with efficiencies three or four times better than the best CFL and LED lamps, without any flickering or warm up time.

Joseph Swan's light bulb!!

Jim

Naughty Nigel
13th January 2016, 11:52 AM
Joseph Swan's light bulb!!

Jim

Your are quite right Jim, but Thomas Edison made the light bulb a commercial success. :)

Jim Ford
13th January 2016, 12:27 PM
Your are quite right Jim, but Thomas Edison made the light bulb a commercial success. :)

Ford made the motor car a commercial success, but he didn't invent it.

;^)

My understanding is that Joseph Swan wanted to give the light bulb to the World, rather than patent it. When he heard that Edison was going to patent it, he negotiated a partnership with Edison.

Jim

wornish
13th January 2016, 12:32 PM
I hate CFLs too.
The claimed wattage is one thing but the key factor is how much light they emit in the visible spectrum i.e the Lumens. If you read the small print on the boxes most of them emit a lot less lumens than an equivalent traditional bulb.

OM USer
13th January 2016, 03:17 PM
Like other posts have mentioned, we use CFLs for hallway and stairs where they can be left on during the evening for safety (these are quoted at 9W). The bathroom has LED GU10s which I found in Tesco's and have no problems with, they seem as bright as the halogen equivalent. I like a bright room for reading/working and have yet to find anything to replace the old 100W incandescant bayonets for sheer overall illumination. I did notice that Tesco's had (past tense as they have supply problems) some reflector small screw LED bulbs which I would like to try someday.