Low-cost LEDs to slash household electric bills

Jan 29, 2009
This is the severn Bridge illuminated with white GaN LEDs.

A new way of making LEDs could see household lighting bills reduced by up to 75% within five years.

Gallium Nitride (GaN), a man-made semiconductor used to make LEDs (light emitting diodes), emits brilliant light but uses very little electricity. Until now high production costs have made GaN lighting too expensive for wide spread use in homes and offices.

However, with funding from the Engineering and Physical Sciences Research Council (EPSRC), the Cambridge University based Centre for Gallium Nitride has developed a new way of making GaN which could produce LEDs for a tenth of current prices.

GaN, grown in labs on expensive sapphire wafers since the 1990s, can now be grown on silicon wafers. This lower cost method could mean cheap mass produced LEDs become widely available for lighting homes and offices in the next five years.

Based on current results, GaN LED lights in every home and office could cut the proportion of UK electricity used for lights from 20% to 5%. That means we could close or not need to replace eight power stations.

A GaN LED can burn for 100,000 hours so, on average, it only needs replacing after 60 years. And, unlike currently available energy-saving bulbs GaN LEDs do not contain mercury so disposal is less damaging to the environment. GaN LEDs also have the advantage of turning on instantly and being dimmable.

Professor Colin Humphreys, lead scientist on the project said: "This could well be the holy grail in terms of providing our lighting needs for the future. We are very close to achieving highly efficient, low cost white LEDs that can take the place of both traditional and currently available low energy light bulbs. That won't just be good news for the environment. It will also benefit consumers by cutting their electricity bills."

GaN LEDs, used to illuminate landmarks like Buckingham Palace and the Severn Bridge, are also appearing in camera flashes, mobile phones, torches, bicycle lights and interior bus, train and plane lighting.

Parallel research is also being carried out into how GaN lights could mimic sunlight to help 3m people in the UK with Seasonal Affective Disorder (SAD).

Ultraviolet rays made from GaN lighting could also aid water purification and disease control in developing countries, identify the spread of cancer tumours and help fight hospital 'super bugs'.

Source: Engineering and Physical Sciences Research Council

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DGBEACH
4.2 / 5 (5) Jan 29, 2009
C'mon guys, less talk and more action! The sooner those parts are available the sooner people like me can start integrating them into products for the masses.
Adam4260
3.2 / 5 (5) Jan 29, 2009
@dgbeach: patience, master luke...
Doug_Huffman
2 / 5 (9) Jan 29, 2009
D'masses?

CFL are rammed down our throats despite the Hg and unpleasant lighting. LEDs are only, so far, unpleasant. Will you pander to the lowest common denominator of your market, marketeer? NEW AND IMPROVED, more expensive progress for the sake of progressivism, willy-nilly.
DGBEACH
3.1 / 5 (10) Jan 29, 2009
LEDs cannot be surpassed for their efficiency at producing light, Doug. This has nothing to do with always pushing new and improved, or making money...I want to bless my children with efficient lighting, that's all!
Our generation paid too little attention to the damage we were doing to our environment, and now its time to set things right again.
And I totally agree with your take on CFLs...they are an abomination, dangerous, and badly engineered! They are just another example of the crap we got during the Bush years! I just hope that LED technology will advance fast enough to circumvent the environmental damage that so many CFLs will do.

Yes, I know, patience. :)
Soylent
3.7 / 5 (7) Jan 29, 2009
CFL are rammed down our throats despite the Hg and unpleasant lighting.


Breaking a CFL is less dangerous than eating a piece of fish; it's elemental mercury, not methyl mercury and you're not going to press your nose right up against a broken CFL and inhale.

Incandecent lightbulbs come in only one colour, fugly yellow 2700K; CFLs come in any colour you want, including fugly 2700K yellow, daylight spectrum and UV.
Soylent
1 / 5 (7) Jan 29, 2009
LEDs cannot be surpassed for their efficiency at producing light, Doug.


Most LEDs are less efficient than fluorescent lighting. The few cutting edge prototypes who aren't still can't beat low pressure sodium(fugly yellowish street-lights) and don't have a chance against high-pressure sodium(hideous pure yellow).
barakn
4.4 / 5 (9) Jan 29, 2009
All lights operate at nearly 100% efficiency during the heating season.
ryuuguu
2.9 / 5 (8) Jan 29, 2009
Is there any reason LEDs keep getting touted as the replacement lighting fixture. They are less effcient than flourencent which is alreay here. Yes there is mecury involved but if your in the US, more mecury is released in generating the extra electricy(from coal) to run less effceint lighting than in make CFL bulbs.
Soylent
3.4 / 5 (7) Jan 29, 2009
All lights operate at nearly 100% efficiency during the heating season.


Nope. Heating up the ceiling won't do you much good unless you have some very strange air circulation in your house.

Your definition of efficiency is screwy. Using the same definition a heat pump is 300-500% efficient; and the theoretical maximum allowed by the second law of thermodynamics is well into the thousands of percent.
Soylent
4 / 5 (4) Jan 29, 2009
Is there any reason LEDs keep getting touted as the replacement lighting fixture. They are less effcient than flourencent which is alreay here.


Well, in principle someone might commercialize the prototype LEDs that are more efficient than fluorescent lighting and people like to take out victory in advance.

OLEDs can be made into neat area lights or even integrated into clothing, packaging.
deatopmg
2.4 / 5 (7) Jan 29, 2009
The LEDs driving the red/orange phosphor have a lifetime of 100,000 hrs but the phosphor only has a lifetime of ~10,000 hrs to ~50% output not unlike CFL's, so the output of the LED becomes bluer (and of lower efficiency/quality) with time. The lumen efficiency of (harsh) white LED's widely available is 20 - 40 lumens/Watt only slightly better than incandescent bulbs but 200 - 300% WORSE than CFL's at 60 - 80 lumens/Watt. NO DGBEACH, LEDs are not the most efficient way to generate light (Bush's fault), >100 lumens/Watt are routinely reported but just try to find them in ANY commercially available device, 20L/W is typical. Common HPS lamps produces light at up to 140 lumens/W of crappy light and MH variants range from 60 to 100 l/W w/ ok to excellent CRI's.

The widely available cheap CFL's produce horrible light ((Bush's fault, of course) but for a premium one can purchase bulbs with a excellent, >90, CRI's ranging in color temperatures from 6000°K to 3000°K. Fluorescents can be made w/ only traces of Hg but the price goes up (I don't know if it costs significantly more to produce or the mfgrs can just charge more for the patented clean technology - but probably Bush's fault too). Both have been available for >10 yrs.

Recently, some information was published that tungsten, from bulb filaments, MAY be causing environmental problems. What problems will gallium cause in the future?
lengould100
1.7 / 5 (3) Jan 29, 2009
white LED's widely available is 20 - 40 lumens/Watt only slightly better than incandescent bulbs but 200 - 300% WORSE than CFL's at 60 - 80 lumens/Watt.

Exactly what I've seen too, so far. I note the specific absence of any efficiency claim, or data which could provide th information, in the article above.
JohnSawyer
5 / 5 (7) Jan 29, 2009
The whole point of the article is not that current, affordable LEDs are more efficient than CFLs--it's that LEDs will, in the not too distant future, with more development, be substantially more efficient at generating light than CFLs. So any complaints about current LED technology is pointless--that's not what's being discussed.
googleplex
2.8 / 5 (5) Jan 29, 2009
Breaking a CFL is less dangerous than eating a piece of fish; it's elemental mercury, not methyl mercury and you're not going to press your nose right up against a broken CFL and inhale...


Wrong.

In that case why does the federal government warn you to leave the room if you break one, and don't vacuum it up. As far as I am aware the same warning does not come with fish. Even the conservative EPA has some worrying advice.
http://www.energy...cury.pdf

How should I clean up a broken fluorescent bulb?
Because CFLs contain a small amount of mercury, EPA recommends the following clean-up and disposal guidelines:
1. Before Clean-up: Air Out the Room
%u2022 Have people and pets leave the room, and don't let anyone walk through the breakage area on their way out.
%u2022 Open a window and leave the room for 15 minutes or more.
%u2022 Shut off the central forced-air heating/air conditioning system, if you have one.
2. Clean-Up Steps for Hard Surfaces
%u2022 Carefully scoop up glass fragments and powder using stiff paper or cardboard and place them in a glass jar with metal lid (such as a canning jar) or in a sealed plastic bag.
%u2022 Use sticky tape, such as duct tape, to pick up any remaining small glass pieces and powder.
%u2022 Wipe the area clean with damp paper towels or disposable wet wipes. Place towels in the glass jar or plastic bag.
%u2022 Do not use a vacuum or broom to clean up the broken bulb on hard surfaces.
3. Clean-up Steps for Carpeting or Rug:
%u2022 Carefully pick up glass fragments and place them in a glass jar with metal lid (such as a canning jar) or in a sealed plastic bag.
%u2022 Use sticky tape, such as duct tape, to pick up any remaining small glass fragments and powder.
%u2022 If vacuuming is needed after all visible materials are removed, vacuum the area where the bulb was broken.
%u2022 Remove the vacuum bag (or empty and wipe the canister), and put the bag or vacuum debris in a sealed plastic bag.
4. Clean-up Steps for Clothing, Bedding, etc.:
%u2022 If clothing or bedding materials come in direct contact with broken glass or mercury-containing powder from inside the bulb that may stick to the fabric, the clothing or bedding should be thrown away. Do not wash such clothing or bedding because mercury fragments in the clothing may contaminate the machine and/or pollute sewage.
%u2022 You can, however, wash clothing or other materials that have been exposed to the mercury vapor from a broken CFL, such as the clothing you are wearing when you cleaned up the broken CFL, as long as that clothing has not come into direct contact with the materials from the broken bulb.
%u2022 If shoes come into direct contact with broken glass or mercury-containing powder from the bulb, wipe them off with damp paper towels or disposable wet wipes. Place the towels or wipes in a glass jar or plastic bag for disposal.
5. Disposal of Clean-up Materials
%u2022 Immediately place all clean-up materials outdoors in a trash container or protected area for the next normal trash pickup.
%u2022 Wash your hands after disposing of the jars or plastic bags containing clean-up materials.
%u2022 Check with your local or state government about disposal requirements in your specific area. Some states do not allow such trash disposal. Instead, they require that broken and unbroken mercury-containing bulbs be taken to a local recycling center.
6. Future Cleaning of Carpeting or Rug: Air Out the Room During and After Vacuuming
%u2022 The next several times you vacuum, shut off the central forced-air heating/air conditioning system and open a window before vacuuming.
%u2022 Keep the central heating/air conditioning system shut off and the window open for at least 15 minutes after vacuuming is completed.
Nik_2213
5 / 5 (2) Jan 29, 2009
Pretty please, may we have affordable, plug-n-play LED replacements for 3-ft, 4-ft and 5-ft fluorescent tubes ?? We replaced our kitchen and bathroom ceilings' incandescent lighting with 'tubes' twenty-some years ago, saved a fortune on electricity and replacement bulbs. Of course, if we'd stayed with 'tungstens' in ES/BC or 'eyeball' mounts, we could now just pop in LEDs as CFLs expire...
gopher65
5 / 5 (3) Jan 29, 2009
The main reason why I dislike CFLs is that are difficult to use to their full potential, whereas with an LED you just plug it in and let it run.

CFLs burn out very very quickly if you flip them on and off, while LEDs don't. In commercial lighting this doesn't matter, cause the lights get flipped on and they just stay on. But around the house? I flip lights on and off like crazy as I enter and leave rooms, closets, pantries, etc. CFLs just can't handle that.

Also, LEDs can be easily made to work at their stated efficiency in any (standard) environment. With CFLs many things decrease both the lifespan of the bulb and the efficiency: environmental temperature, changes in temperature, air circulation (that's a big one for many of the CFLs), orientation of the bulb (they only live up to their potential if they are vertical with the bulb pointing up (ie, a lamp)), and one or two other things that I can't remember off the top of my head. LEDs? Plug in, and go.

So yes, *in a laboratory setting* the current generation of CFLs is more efficient than the current generation of "cheap" LEDs. In real life the difference narrows to practically nothing.
dachpyarvile
3.4 / 5 (5) Jan 30, 2009
...And I totally agree with your take on CFLs...they are an abomination, dangerous, and badly engineered! They are just another example of the crap we got during the Bush years!...


Ahem! Bush??? It was Al Gore who was pushing CFLs. He even directed the production company that produced his "Inconvenient Truth" video to include a free CFL with the initial copies of the video for public consumption!

Why is it that people get the Dems and Republicans mixed up when bad stuff happens? How do we forget the truth and recycle error, blaming the bad stuff on the wrong people? :)
dachpyarvile
3 / 5 (6) Jan 30, 2009
Pretty soon, it will be Obama and his new energy chief who will be pushing more of the same in the name of AGW theory. Ten years later, Bush will still get the blame. Heheh!
dachpyarvile
3 / 5 (6) Jan 30, 2009
Almost forgot...it actually was the Clinton Administration that gave us the CFL as we now know it, not the Bush Administration.

Now we have another Clinton Administration in the White House recycled into the Obama Administration. So much for promised change. :)
Yes
2.8 / 5 (4) Jan 30, 2009
This is great news for the environment.
Unfortunately for the consumers the current cost of electricity is mostly infrastructure and maintenance related.
If people start to consume less, then the electricity companies will perceive less income and will not be able to pay salaries and copper cables and so on. Therefore they will simply raise the cost of electricity KWH and in the end you will be paying just the same.
Except the people who decided to wait for changing out the bulbs. They will be paying more for feeding their old style bulbs with more expensive electricity just as is happening now with the new fluorescent bulbs.
O yes, that people is probably the poor people!
PaulLove
5 / 5 (2) Jan 30, 2009
Popular thread :)

For the fellow who said lights are 100% efficient in the heating season, congrats you are correct any waste heat generated by the lighting in your house is less energy you will use in your dedicated heating system to heat your house.

For the question of Mercury in broken bulbs, the epa has guidelines for cleanup true. For your personal home wipe down the area avoid being careful to avoid being cut vent the area if you can. The affected area will be larger than you might think small shards can travel several feet from the point of impact. The good news is if you only change bulbs every 3-7 years you will have significantly fewer broken bulbs than if you are changing them every 3-4 months. the bad news is welcome to the industrial society there are trace amounts of mercury in alot of stuff food water etc. the best you can do is try to avoid significant direct contact.

For those of you complaining that they now want you to switch to new LED lights just to make more money, the LED lights are now(expensive thought they may be) and will be and improving option. This is just an option to consider when in they next few years you start to replace the CFL's you currently have begin to burn out not to encourage you to throw them all away now in replace with new bulbs. When you switched to CFL's did you immediately throw away all your existing bulbs and replace every light in your house with them? I didn't I replaced bulbs as the burned out with replacement bulbs that were more efficient (CFL's). Didn't seem right to start my personal green initiative by immediately generating a pile of trash.

For those of you who spend your time trying to blame pollution on your various political parties and leaders. It is important to note that your leaders all swear oaths to the United States it is depressingly shameful that both they and you seem to believe seem to believe and behave as though they are instead swearing oaths to the party rather than the nation. Take your caveman "Ug me party good you party bad" attitude back the the sewers where you both live.
Soylent
2.3 / 5 (3) Jan 30, 2009
Almost forgot...it actually was the Clinton Administration that gave us the CFL as we now know it, not the Bush Administration.


What are you driveling about? It was invented in 1973 by Ed Hammer working at General Electric in response to the oil crisis.

I've been able to buy them in stores since the early 90's and we have no Clinton Administration to blame them on here in Sweden.
Soylent
2.3 / 5 (3) Jan 30, 2009
Wrong.

In that case why does the federal government warn you to leave the room if you break one, and don't vacuum it up. As far as I am aware the same warning does not come with fish.


Yes, the same paranoia comes with fish. Don't eat oily fish more than once per week, especially not children. Try to find fish from low mercury areas etc.

It's only on the order of about 1000 times as much mercury in a CFL as there is in a piece of oily fish(e.g. salmon, mackerel), most will stay on the glass when the bulb is broken. Of that which enters vapour form, very little will be inhaled and absorbed since the air flow out the ventilation is so much higher than into and out of your lungs. And it's elemental mercury, which is far less dangerous than fat soluble methylmercury from coal plants that you'll find in the oceans.
googleplex
2 / 5 (1) Jan 30, 2009
Wrong.

In that case why does the federal government warn you to leave the room if you break one, and don't vacuum it up. As far as I am aware the same warning does not come with fish.


Yes, the same paranoia comes with fish. Don't eat oily fish more than once per week, especially not children. Try to find fish from low mercury areas etc.

It's only on the order of about 1000 times as much mercury in a CFL as there is in a piece of oily fish(e.g. salmon, mackerel), most will stay on the glass when the bulb is broken. Of that which enters vapour form, very little will be inhaled and absorbed since the air flow out the ventilation is so much higher than into and out of your lungs. And it's elemental mercury, which is far less dangerous than fat soluble methylmercury from coal plants that you'll find in the oceans.


It depends on the fish. You can buy fish oil capsules that are screened for mercury content. I agree with you that coal plant mercury is a far bigger health problem. However that does not eliminate the added toxicity of putting CFLs in kiddies rooms. The labelling of CFLs is very poor and the EPA advice needs to be included on every package IMHO.
On the coal plant issue they need to put scrubbers on the smoke stacks. It is far easier to deal with concentrated toxic waste than clean up vast swathes of the environment. With improved scrubber technology coal would be a wonderful source of power for centuries. It seams scientifically and morally insane to me that they don't just scrub out the mercury at the stack. This is another area where the government is failing to regulate.

The reality is that any level of mercury is toxic. It is accumulative and has an affinity to bind with nervous tissue.
Perhaps Soylent you have a high risk tolerence. Some folks live in the moment and have no regard for such details. There is an economic argument here. The illnesses caused by these toxins have a heavy health care cost. This impacts insurance premiums/tax etc. Clearly it is cheaper to pay for a scrubber on smoke stacks than to pay for health care.
DGBEACH
5 / 5 (3) Jan 30, 2009
*PaulLove* believes that CFLs will last years and years and years...but in my experience they've only lasted a fraction as long as the incandescents they replaced. And when they blew it was dramatic and smelly!
I don't like them for these reasons and because of the dangerous UV they give off.
LEDs are trouble-free, easy to control, and ultimately, easy to dispose of (whenever they eventually do finally dim to dark).
dachpyarvile
4 / 5 (3) Jan 30, 2009
Almost forgot...it actually was the Clinton Administration that gave us the CFL as we now know it, not the Bush Administration.


What are you driveling about? It was invented in 1973 by Ed Hammer working at General Electric in response to the oil crisis.

I've been able to buy them in stores since the early 90's and we have no Clinton Administration to blame them on here in Sweden.


You are confusing the miniature U-tube FL with the CFL. The miniature U-tube FL was the predecessor of the current CFL. The CFL models in most common use today is of the twist variety which were sold in America in 1997.

I am aware that American political parties do not affect usage in other countries, per se, but I was addressing a fellow American of the class that likes to blame Bush for everything from bad breath to toe-rot, when the evidence squarely places the blame into the Democratic camp.

It is just that they have the Media in their pockets here and can spin the truth effectively enough to make the people believe whatever they want. As Hitler said, telling a lie often enough will cause it to be believed as truth by the masses.

Nonetheless, there is politics afoot even in your own backyard as country after country follows political suit and makes the move to banning incandescent lighting in order to cut emissions. This means more CFLs in homes and a major move in jumping out of the frying pan into the fire--environmentally speaking, that is.

That said, I am looking forward to the advent of cheaper LEDs. I think they will be better than CFLs and more environmentally friendly (not to mention, safer).
jonnyboy
1 / 5 (1) Jan 30, 2009
Popular thread :)

For the fellow who said lights are 100% efficient in the heating season, congrats you are correct any waste heat generated by the lighting in your house is less energy you will use in your dedicated heating system to heat your house.

For the question of Mercury in broken bulbs, the epa has guidelines for cleanup true. For your personal home wipe down the area avoid being careful to avoid being cut vent the area if you can. The affected area will be larger than you might think small shards can travel several feet from the point of impact. The good news is if you only change bulbs every 3-7 years you will have significantly fewer broken bulbs than if you are changing them every 3-4 months. the bad news is welcome to the industrial society there are trace amounts of mercury in alot of stuff food water etc. the best you can do is try to avoid significant direct contact.

For those of you complaining that they now want you to switch to new LED lights just to make more money, the LED lights are now(expensive thought they may be) and will be and improving option. This is just an option to consider when in they next few years you start to replace the CFL's you currently have begin to burn out not to encourage you to throw them all away now in replace with new bulbs. When you switched to CFL's did you immediately throw away all your existing bulbs and replace every light in your house with them? I didn't I replaced bulbs as the burned out with replacement bulbs that were more efficient (CFL's). Didn't seem right to start my personal green initiative by immediately generating a pile of trash.

For those of you who spend your time trying to blame pollution on your various political parties and leaders. It is important to note that your leaders all swear oaths to the United States it is depressingly shameful that both they and you seem to believe seem to believe and behave as though they are instead swearing oaths to the party rather than the nation. Take your caveman "Ug me party good you party bad" attitude back the the sewers where you both live.

All lights operate at nearly 100% efficiency during the heating season.


You are both right in a very narrow sense but only if you examine your energy usage for part of the season due to the fact that the gains in the winter are offset by massive losses during the summer when you have to remove the extra heat placed into your environment.

And unless you live in a very strange place the cost to heat a home with electricity is much higher than to heat with natural gas so that even during the winter they are not very cost effective.
gopher65
3 / 5 (1) Jan 31, 2009
jonnyboy: Studies in Canada have found that extra heat created during the summer (and the extra strain placed on air conditioners) is far less than the extra heating energy saved during the winter. In fact, they found that in cold climates (Canada, northern Europe, the Northeastern US, Russia, etc) CFLs INCREASE the total use of energy as a whole (heating oil, natural gas, etc), even though they slightly (*slightly*) decrease the total electricity consumption.

CFLs do make quite a difference in energy savings in warmer climates though, according to one study.
localcooling
3 / 5 (2) Feb 01, 2009
barakn - Jan 29, 2009, writes:
All lights operate at nearly 100% efficiency during the heating season.

This is not true because of using 110W of light could be saved to 10W with an LED vs. Old Bulb. The saved 100W can feed a air heat pump -> 200W worth of "house heating"

The reason for this is that outdoor air contains energy even when cold. Comfort heat in a house is a certain amount of energy with in a certain amount of cubic meter space. If 100 cub meter space needs 100 J (energy units) to give comfort climate, then you can take 400 cub meter 1/4 temperature and concentrate it to 100 cub. meter. This is called HEAT PUMPING !! It takes approx. half of the energy compared to heat indoor with a bulb lamp or ilk.
DGBEACH
5 / 5 (1) Feb 02, 2009

And unless you live in a very strange place the cost to heat a home with electricity is much higher than to heat with natural gas ...

Yes Quebec is a very strange place :)