back to article Energy-saving LEDs 'will not save energy', say boffins

Federal boffins in the States say that the brave new future in which today's 'leccy-guzzling lights are replaced by efficient LEDs may not, in fact, usher in massive energy savings. This is because, according to the scientists' research, people are likely to use much more lighting as soon as this becomes practical. The greater …

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At last

At last a group with common sense. The whole late progress of the human race has been a progression through stages of greater power use, in the quest for a better life, at no greater cost in man sourced power. They ought to promote these guys to the top of their profession

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Coat

But we won't all be growing older forever

With childhood obesity rates increasing, life expectancy should start dipping again.

Mines the one with the pie in the pocket

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Eh?

I have a 12W LED that's supposedly equivalent to a 60W bulb, but is not noticeably darker than a 100W incandescent bulb and is certainly brighter than the sunlight through the window. If someone decided that they wanted the room to be lit with 5 of these to make the room painfully bright then that still only adds up to 60 W, 40% less than a single 100W bulb. Your still using less electricity!

Not that people are going to do that, but hey. Their arguing that people are going to leave them on for longer because it doesn't cost so much. Sounds fair, until you do the maths. A single 12W LED bulb ran for 24 hours draws marginally less power than a single 100W bulb used for 3 hours. I really can't see how your going to be using more power with LED's...

Now if they wanted to claim that you'd have to use more energy for heating as they produce less heat then they might be onto something, but this just looks like nonsense tbh.

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Anonymous Coward

I have a 15m long drive.

This drive has trees at one side and rocks at another. It also curves and sometimes has things (tools etc) left on it.

If I could do it cheaply, I'd illuminate the driveway. However, I can't- thanks to the odd shape of it (plus I drive up it, so would have to avoid direct-bulb-viewing glare) I'd have to use a good few of them, and this would be bloody expensive with incandescent lights.

LED lights are, however, making it possible to do this. I might even run power to the long-deactivated gaslamps on the pillars at the end. Current power consumption: 0W. Future power consumption: say 100W including a stack of bright LED lights and two larger lamps. That's a LOT of LEDs and a lot of electricity (though, obviously, they'd not be on all day) that wouldn't be used without LED lights.

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12W LED

If it's anything like the LED lights I've seen, it probably is as bright as a 100W bulb - over an angle of a few degrees. The problem is that the 100W bulb spreads the light out over a who sphere, and so it can light the whole room. The LED light on the other hand just projected a spot on the wall / floor. In my old kitchen even 10 of the LED bulbs did not give as much light as the single 60W fluorescent light, so they went back to the shop.

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Well, personally...

"I have a 12W LED that's supposedly equivalent to a 60W bulb, but is not noticeably darker than a 100W incandescent bulb and is certainly brighter than the sunlight through the window. If someone decided that they wanted the room to be lit with 5 of these to make the room painfully bright then that still only adds up to 60 W, 40% less than a single 100W bulb."

I've been waiting ages for cheap LEDs that I can string along behind the picture-rail in my living room in order to have an uplit ceiling with subtle differences in colour and intensity based on mood and time of day. I also have a fairly long L-shaped hall which has funny patterns of light and dark because of where the single light is located.

LEDs will probably end up being used in long strips rather than in single "bulbs".

Think the end of the "lamp post" and instead a great big row of LEDs stretching along the buildings at the side of the street casting uniform light on the pavement rather than a series of amber cones will dull patches in between.

Think aeroplane/cinema-aisle floor-lighting in most offices and public buildings, and think of that being considered a health and safety requirement, hence always on. Think of door-handles that glow constantly in a soft blue, and these being required by health and safety. Think of a stair that has all its edges lit up, and again think about how that ties in with health and safety.

Think of garden ornaments (although they'll probably have their own solar power).

Think of bicycles and motor vehicles with sidelights for added peace-of-mind.

Think of small lights inside all of your kitchen cupboards and appliances, rather than just the fridge and the oven.

Think of a keyboard with LEDs under each key so that the letter glows.

Think of beds with a string of LEDs in the headboard for reading.

Think of some other things that I'm not going to mention cos they might be patentable....

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Stop

Lights

Nah. People will strive for a comfortable light level, not the brightest possible. Technology reached that "comfortable" level decades ago. The average person can already afford blindingly bright lights if they so wish. But they don't. Neither do they strive to have light in unoccupied rooms.

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a drive with gaslamps on the pillars?

Can't you just tell your footmen to stand outside with torches?

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Spot light replacements

I've recently swapped the 50W halogen spot light in my study for 7W LED equivalents, The illuminated area is very similar, but you can choose different "angles" when ordering both. I'd say the LEDs are noticeably brighter, but the colour temperature is no where near what Philips claim, they are supposed to be 2700K tungsten equivalent but they seem much closer to sun light. My wife kept thinking I'd left the blinds open.

They also save in cooling costs.

The guys in this report are probably right that in many case people will just use more and more lighting, but this is a trend that has been going on for ever. In the past, as people got richer they used more candles, then more oil lamps. The fashion for using GU10 and their low voltage equivalent bulbs tended to see a massive increase in the number and strength of lighting. It wasn't uncommon to see single 100W traditional bulbs being replaced with a dozen ceiling mounted 50W spots.

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@Dazed and Confused

>>"The fashion for using GU10 and their low voltage equivalent bulbs tended to see a massive increase in the number and strength of lighting. It wasn't uncommon to see single 100W traditional bulbs being replaced with a dozen ceiling mounted 50W spots."

And bearing in mind the original article's premise, where what you describe happened, was it actually linked to any great change in the price (or affordability) of electricity, or to entirely unrelated factors?

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Grenade

RE: Well, personally... ( game changer )

there is always the case that people will build larger homes so they can put in more lights and keep that constant energy expense line going another century or so.

the part these people are missing is that part where technology and the cost of that technology change the game. What was it which caused the limits which stuck the number at the .72 number for so long? And how much as it wavered from that number over the years and why?

Unless LED lighting manufacturers start building in a shorter lifespan for the LED lights, just the constant cost of replacing lights( or the lack of ) should be enough to change the game. Maybe it's time for a bend in that line( at .72 percent ) to happen.

grenade, because it's a game changer

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Bronze badge

Re: 12W LED.

Sorry, I should have been more specific. It's a 12W 240V LED in "bulb" style that slots into a standard UK Bayonet Clip fitting, not a MR16/GAU10 12V spot that I guess you've seen. It lights up the entire room with the single bulb, not just a spot.

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@ Well, personally

... think not, because they could've already done that with rows of lower wattage incan bulbs instead of fewer higher wattage versions. Can it be done? Sure, but maybe the answer is spending daylight hours awake, using sunlight as man always has, and lighting only your immediate area when it's dark.

Increases in complexity towards a novel end, quickly become a burden upon themselves.

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@dave wilson

fashion, usually the major driving force in these things

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FAIL

Idiocy need no be rewarded

I'm betting that the average consumer is actually smarter than the boffins that came up with this drivel.

I'm using CF lighting and I use the same illumination as before, but use less energy. LED should be even better once perfected. My monthly electricity proves the savings.

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Megaphone

think...think...think...

Think of the children...!

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They are a con

Spotlight downlighters I mean. It has been fashion driven by the visual excitement of spotlighting the new polished wood flooring. And the result is what it says on the tin - spots of light !

Initially led will replace spotlights cos that is how they are made now. Ultimately solid state science will produce a decent panel light, then we are in business.

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Not really.

I've been living in the same flat for the last 20 years.

Day one. One ceiling light fitting. Still there. Used 100W bulb.

Years later, one ceiling light, one table light. Used 60W bulb.

About ten years ago, switched to low energy bulbs.

Last year. Added a desk light. low energy bulbs now used throughout. Normally jut the ceiling light on, with occasional use of the desk light, or just the table light.

In total, I'm less electricity to light my living room than I did on day one.

Cheaper lighting does not automatically mean more used.

Sorry..You will have to find a better way to justify using more electricity than you actually need to.

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Anonymous Coward

I see your problem...

"I'd say the LEDs are noticeably brighter, but the colour temperature is no where near what Philips claim, ... ... ... they seem much closer to sun light. My wife kept thinking I'd left the blinds open."

Here's your energy use problem: closing the blinds and turning the lights on!

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Black Helicopters

"Should" but still haven't

In fact, life expectancies have continued to grow despite the increasing obesity rates which can only be explained one of two ways: either medical advances are outpacing our dangerous wastelines, or the "obesity epidemic" is a bunch of scaremongering horse shit brought to you by the same people (left or right) that disapprove of your lifestyle and want government to fix you.

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GDP trend...

"Unless LED lighting manufacturers start building in a shorter lifespan for the LED lights, just the constant cost of replacing lights( or the lack of ) should be enough to change the game. Maybe it's time for a bend in that line( at .72 percent ) to happen."

This is a reference to the percentage of per capita GDP spent on lighting, right? We now have lower wattage lighting producing similar light levels. Cue the never ending rise in electricity prices to fix up any deviation from 0.72%. There may be energy savings but I doubt there'll be any cost savings. In previous periods the fuel type was changing (candle -> gas -> electric) and population levels, and hence resources, were not what they now are - high and constrained respectively.

I've read a few pieces on LED lights now and I recall it takes about 9 years on average for the cost savings of replacing all your incandescents with LED lights (at fixed energy costs I believe). CFLs take about 6 years using the same assumptions. Obviously fixed energy costs are a big but necessary assumption for a starting point and I can't remember the details regarding the number and/or mix of incandescents and halogens - the old "average household" problem. I believe there are still some issues with 240v vs low voltage ones as well - lifetime and quality of light I think. Article also mentioned the CREE brand as being on the money for quality but I've found them bloody expensive where I live.

One thing I have noticed though from browsing the houses for sale locally is that some of the new or renovated ones have kitchen lighting that you could use to land a light aircraft. These aren't as good as some previous examples I've seen but illustrate the point...

http://www.realestate.com.au/property-house-qld-balmoral-106727770

http://www.realestate.com.au/property-house-qld-bulimba-106775906

http://www.realestate.com.au/property-house-qld-bulimba-106695126

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Optics my friend, optics

Yes leds can be "spotlighty", but you just use a wider spread optics and bobs your uncle.

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Anonymous Coward

Ten times more light?

I'm sure they're right to an extent: the amount of light used will go up - at least, it will while there is still cheap energy.

But LEDs are something like 10x more efficient than the halogens that they (mostly) replace. Do they really think we're going to use 10x more light? We'd need to wear sunglasses in the house! I'd believe twice as much light used in the developed world, but not much more than that.

However, the important point to me is that LEDs would let us retain the same level of lighting we currently enjoy, even when oil is $300/barrel or more - they may not represent a major leap forward, but they may stop us sliding backwards.

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Bronze badge

10x more light isn't that much

Remember we perceive light levels logarithmically; it's only about 10dB up.

The trend to plaster your ceiling in gross numbers of cheap mains halogen fitments isn't much to do with light levels but merely fashion. Replace those with 3W LEDs (which are available for about £5 a piece now if you shop around) and there will be a step change in energy consumption. The main problem with these LED replacements - assuming you buy reliable ones - is that they are deeper than the halogen dichroics.

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Thumb Up

Re: Ten times more light

3D TV glasses do cut out some light so brighter lights will enable you to keep them on when you make a cup of tea. Plus any fule kno wearing sunglasses indoors is cool.

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Unhappy

3w LEDs

Yes, I've got two of those in the kitchen. They actually make the room darker when you turn them on.

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Paris Hilton

To the horror of the enviro-whackos

This statement, "increasing human productivity and quality of life" will bring about much derision from the no-growth, flat-Earth, enviro-Marxists.

I now have an 11W LED spot lamp illuminating the flag in my front yard. It lights up the front of my house about as well as a 60W Halogen. Not as focused as I would like, but that aside, it is pretty damned impressive. I could put four of them on my flag now, and really light it up, bringing my consumption to 44W. See how power hungry I am already?

For Earth Day this year I lit up Old Glory with four 100W Halogens. Yes, 400W of freedom-illuminating power, baby! I probably paid an extra $.50 for it, but since I have $.50 to spare and all. Of course, once these whack-jobs get their way through the abominable EPA, that would also be taxed extra for my associated carbon footprint.

What bullshit. Yes, bullshit. Cap and Trade is nothing more that punishment for consuming, period. None of this "fair share" rubbish. If I have the $.50 to pay for an hour of 400W of light output, then who the carp are you to say that is more than my "fair share?" I put into the system by working, and therefore should be able to avail myself of more product.

And this ecosystem thing, human arrogance, plain and simple, to think that we could have the effect on a planetary system the way these so-called experts predict. We will have a menial effect on Earth, short of a thermonuclear war which obliterates us and half the planet -- which Earth will easily shrug off in a few hundred thousand years, ready for the next half-wits to walk on her.

"Conservation does not mean going without, it means avoiding waste." Best quote I have read in a while, and I wish I knew to whom I owe the credit.

Anyway, enough ranting. I have work to do so that I can pay for next year's Earth Day display.

And while I am at it, that "Earth Day" light-out business is more bullshit. "Oh, we're gonna show governments how serious we are by NOT doing something." Sounds about right, actually. A lot of these people tend to get ahead by NOT doing something, while the rest of us bust our humps and accidentally participate. Screw that.

Paris, screw that.

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Anonymous Coward

Phew....

...for one minute then I belived there is a finite amount of oil and gas. Thanks for correcting us.

Besides the glow from the back of your neck will illuminate us for decades....so who's to worry.

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Troll

I had to laugh at him

@ Alan W. Rateliff, II

>We will have a menial effect on Earth

So deforestation, species extinction, ocean acidification, building cities which cause heat pools and pollution hotspots, poisoning water with pharmaceutical byproducts, draining most of the freshwater from rivers and lakes, dumping vast amounts of nitrogen into water supplies, leaking billions of gallons of oil into the sea, etc etc etc are "menial"?

Even ignoring the stuff about global warming (because the general ignorance of that is not the point here), we're having an absolutely massive effect on the environment.

Go look at the Aral sea and tell me who nuked it and how the damage there matches a radioactive blast pattern?

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@Alan W. Rateliff, II

Excellent parody, Al - for a minute, I was almost taken in by it.

Sometimes it can be pretty hard to tell the deliberate wind-up from the unknowingly self-parodying, and you got the balance just about perfect, not too far over the top, and with a style that was spot-on.

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Boffin

aral sea

The Aral Sea is where it is because almost all of the water that used to go to it has been diverted to the irrigation of cotton. Another fine socialist engineering project you can see from space. Not likely to go back anytime soon, as the majority of people in Uzbekistan decided they like making money from cotton. It pays for their air conditioners, keeps the doors open, lights on and all that.

What you are implying is a nuclear blast pattern is a dramatically receding coastline. The two don't look anything alike.

Paradoxically, if there is no climate change, about the only way to save the Aral would be to make people wear clothing made of synthetic materials, and ban clothing that uses too much cotton plunging the region back into abject poverty. In another paradox, the increased rainfall from global warming may be the only way to realistically return the Aral to its old proportions.

Most of our laments about the state of the environment can be summed up in two phrases:

1) "There are too many people"

2) "We don't like change"

Sorry -- neither looks likely to me to be going to do what seems to be desired, and so the best thing we can do is put our teeth back in our mouths and adapt.

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That'd be...

"Enlightened policy decisions may be necessary to partner with the technologies to have big impacts."

That would be tax increases then, wouldn't it...?

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Obviously

They will have to force that 0.72 % GPD by ratcheting up the only tool at their disposal.

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Flame

"Presented with the availability of cheaper light"

1) Using LED lighting is only going to be cheaper than today's lighting if energy prices don't massively go up

2) Not everyone in the world is American, although most of the world's resources are consumed by or on behalf of Americans

3) Even some Americans know that enough is enough, and that if too much of something costs more than enough of something, they'll stop at enough.

QED.

Lewis, given the choice of a green tree or a wrong one, once again chooses to bark up the wrong tree.

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Popular is a color

Of course, some folks would have us believe that the "green" one is:

* The right one

* Actually green

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Alert

in cold countries - not at all!

In cold countries, energy efficient lighting will NOT save energy.

This is because with non-energy efficient lighting the bi-product of the inefficiency is heat!

In this case, the bi-product is useful and you will not save any energy at all.

In hot countries, where air conditioning is essential you will definitely save energy as the bi-product of normal bulbs is counter productive to the desired temperature.

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Thumb Up

Ever-egged, but a good point

A good point but over-stated. Not "not at all" but "less than you think".

A bulb emitting heat neat the ceiling is a sub-optimal way of heating a room (especially if upstairs does not need heating at the time). Also electricity generation and transmission is inefficient, compared to generating the same heat in a good modern condenser boiler.

Nevertheless, anyone who calculates energy saved by taking the difference in wattage between incandescent and LED replacement, and multiplying by hours used, will be very disappointed. At best it'll be half that. My guess is one third to one quarter, since in the UK the need for lighting in summer is greatly reduced by the long daylight hours.

And a point about hot countries. Here, not only is waste heat truly wasted, but they are usually running an air-con to get rid of it. So in these places, the energy saving multiplier will be greater than one.

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well then I guess...

we need Heat Emitting Diodes as well.

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Warm countries use lights in the summer

In southern Europe (I can confirm Spain and Italy) it's common practice to close the shutters during the day to keep the sun from baking the house and that means using the lights more often.

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Well noted

There's actually an interesting example of it in the States. A lot of cities are switching from incandescent lighting to LEDs for stop lights. In places like California, it's a nobrainer, and is very successful. In places like Chicago, however, they had to switch back to incandescents, because in the winter, snow would accumulate in the light ports and block light. Using incandescents there would melt away the snow, a useful side effect that LEDs did not provide.

However, I wonder about the energy efficiency of a 100W bulb vs a 12W light and a 80W heater. It still might be economical to have the LEDs because then each do what they're best at. That is, a light must be somewhere high, so the heat generated by the 100W is more likely to be lost through the roof, whereas the dedicated heater can be localized or part of central heating, where the heat can be better used and delivered.

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Pint

Is anyone yet working

on a Beer Emitting Diode?

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Pint

With LED + heater

you could even only switch the heater on when it snows...

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Boffin

Missed a trick

Central Bedfordshire [unitary authority] are swapping old concrete-posted low-pressure Sodium street lamps for LED units on steel poles. They are nice and bright and so far I have not detected any QRM from them. However, the designers have missed a trick. The inclusion of a PIR sensor to only power the light when needed would save on the electricity bill and the un-welcome light pollution. But that would be too easy! And the old-folk would complain!!

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Coat

Tax

The solution is obviously to tax light. That'll show 'em.

Mine's the one with a big picture in the pocket.

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I don't buy it

We've been running CF bulbs in our house for many years now, and we don't leave our 16 watt CFs on any longer than we left the 100 watt incandescents that they replaced. If those got replaced with 4 watt LEDs, I still wouldn't leave them on any longer.

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Bronze badge

I call bollocks.

My GFs kitchen/diner had 1100 watts of GU10 50W bulbs in there - sounds horrendous, but it wasn't more than you'd expect to see in a room that size.

Replacing these with a 3.5W GU10 LED like one of the newest Exergi or Homewatt bulbs gives about 90% of the light by my measure, of a similar enough colour that you won't notice, and for a total wattage of 77W. Even the highest wattage LED GU10 replacements I've found take 6W, still an order of magnitude better.

To be fair it's also £500 worth of light bulbs, but that's a different argument.

Perhaps in the US they still illuminate their kitchen with a single 60W bulb, who knows?

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Not quite.

The £500 worth of bulbs is not a different argument. That's £500 of bulbs that is going towards the cost per capita on lighting.

So the wattage of the bulbs may decrease, but you spend more on them and then as they get smaller you put them in places you never used to.

Net result - spending the same.

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WTF?

Re: US still illuminate with single 60W bulb

Actually, many of us do (at about 174kWh / yr per bulb). You will find a lot of pitfalls whenever someone bandies about "averages"... Americans use more energy than other countries, and yet most of the people in my neighborhood can only afford 140 - 170 kWh a month (less if you don't have a small netbook computer) for a total of about 2040kWh / yr - less than 1/2 of the UK.

But then, we also can't afford XBox, 56" TV, home wifi, 80K btu aircon...

Averages like the average yearly income in my area is well into six digits, and I don't know any making *that* much. So, who and where is bringing up the average, and what kind of lifestyle do you need to live to pull THAT off?

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