Efficient Lamp: Newsletter Challenge (06/01/11)

The answer is in the question: Efficiency.

From LUMIVERSAL:

Fluorescent lamps are relatively efficient at converting input power into visible light. For purposes of comparison, incandescent lamps convert 2% of their input power into visible light, while typical fluorescent lamps convert 22%.

If that is true. Fluorescent lamps only convert 22% of their input power into visible light, we are wasting a tremendous amount of power. How then can we design lamps that are more efficient? If we could even double it to 44%, would that not then be a huge savings? Would it be possible to achieve say 60, 75 or maybe even 80% efficiency? The genius of man has solved so many incredible problems over the years, how have we let this one get past us? Have we just become complacent because electricity (Power) has been relatively cheap, Lamps plentiful and cheap, so we just haven't bothered to seek a solution to the inefficiency of yesterdays lighting? Is the future in LED lighting? or is there some other, better way?

Just a few random thoughts to get you thinking.

Great idea, I'm surprised no one has thought of this before.

LED lamps are 80% efficient. That's quite an improvement.

Regards.

I add to:

<< compared with fluorescent tubes which being AC driven have instants when they emit no light. >>

It is stroboscpic effect.

You can see in every day life if you ve Flouro lamps lighting and a cieling fan running, try to vary the speed and you will feel it running in reverse.

Or on tv you note the direction of car wheels; changing direction or running in reverse to the car direction.

Speed of Auto-engines was measured by Strobometers and Timimg also was set.

Is in use to measure RPMs .

Stroboscope

Hello, I have the privalage to share some information regarding the question at hand. See the discussion on LPCS, Light Power Cell system.

So in the world of LPCS or Light Power Cell System, the light produced from incandescent and Cfl maybe reused and redistributed. All light fixtures or at least almost all light fixtures has some waste due to design or restrictions of design and LPCS can and does convert that back to usable elctricity. This aplies to LED as well.Of all light that is used on a large scale incandescent is by far the most potent when it comes to converting light to useable electricity. Led's have the same problem as incandescents of heat mangement, if Led's get too hot they burn out. Cfls are the coolest of all the light producers and can produce large amounts of useable electricity by converting the light to useable electrical energy.

Thought I would enter my two cents for your info.\

LPCS /Gary

This shows the way a fluorescent lamp Emits light

The essential component in the process of making light is the inter-conversion of energy. Different types of lamps and lighting devices convert energy in different ways and with differing efficiencies.

In the tungsten lamp, electrical energy heats a filament to a white-hot glow; thus, thermal energy is converted into light energy. Light emission from the solid filament is a continuum and gives a visible spectrum, much like a rainbow. Unfortunately the efficiency with which electrical energy is converted to visible light energy is only about 5-12%.

In the fluorescent lamp, electrical energy is converted into atomic excitation energy (UV) in the mercury vapour atoms inside a tube. The UV is then converted into visible light using phosphors. In this case, the energy conversion efficiency is about twice that of a tungsten bulb at around 22%. However, the spectrum of light emitted by these lamps (when the electrons return to their non-excited state) is not continuous; instead, light is emitted at specific wavelengths and colours corresponding to the electrical energy levels of the mercury atoms.

Replacing the mercury vapour with other gases, such as neon (which gives an orange light) or other inert gases, allows the production of many different coloured fluorescent lamps, used for luminous displays and signs (see image). Different phosphor coatings also change the colour of the light from the lamp.

The question is faulty (I am not the first to say that either) and shows a complete lack of any formal knowledge about any of the current forms of light producers. This in itself is not a bad thing, but the question is posed as though he has some GREAT new question that will help all the scientists and engineers working on future lighting.

Most of the posts (with a couple of notable exceptions) are just as faulty/incorrect.

Anyone wishing to learn something useful would be better off looking at one of the many other CR4 blogs that have already covered this subject to death....and accurately too.

This is just a collection of rubbish (mostly!).

Techart`s comment is as though nobody in the last 50 years has done anything to improve the situation, I personally would be completely ashamed if I had so posted a question without informing myself as best I could beforehand.

But there again, I do know the subject a little as I have read many of the previous blogs covering this on CR4, though I am still no expert. Now wasn't that easy?

Why cannot such people do a few simple searches on CR4 and read up first before posting such childish "questions"?

I'm surprised that no one has mentioned the research that is being put into bio-luminescence. Although it is in the early stages of research it would seem to be something that has a promise of working.

fluorescent lamps have a fluorescent coating, of various composition, possibly zinc sulfide?, that converts the ultraviolet light emitted by the primary excitation by absorbing photons, then quickly transfering energy to a lower energy state by fluorescing from the excited electronic state produced to a lower energy state, resulting in an emitted photon of a visible wavelength. If the resulting electronic state of the fluorescent material is still sufficiently energetic relative to the molecular ground state, then it is possible that a second photon of visible light will be emitted, otherwise this energy will likely be converted to infrared (heat). The materials used generally have a high quantum efficiency of conversion of ultraviolet to visible.

if the given statement is right, than:

10% visible light of 90% emitting light is more visible light than 5% of 100% emitting light!

One relies on heat to cause an item not made to emit light ... to emit light. For example if you heat metal enough (or anything really) it begins to glow.

The other electrically excites gasses that emit light in specific wavelengths because of the specific energy difference between two electron energy states within the atom.

It's possible because in addition to light (EM radiation), the bulb is producing heat. And since an incandescent light relies on heat to create the light, there is a lot more heat loss. This is where the extra wasted energy goes.

Maybe if I put this in numbers instead of words it'll make more sense.

Efficiency is in Watts of visible light/Watts of electricity.

So, in the below examples I'm going to make up some numbers, just to show how it's possible starting with input of energy = sum of the output energies.

An incandescent light relies on heat to produce light. So there is a lot of heat loss. Let's say:100 Watts of electricity = 94 Watts of heat + 5 Watts of visible light + 1 Watt of UV light.

A florescent light relies on changing electrons energy level to create light. So there isn't much heat loss. Let's say:20 Watts of electricity = 1 Watt of heat + 5 Watts of visible light + 14 Watts of UV light

So the efficiency of the incandescent and florescent lights are 5/100 (5%) and 5/20 (25%) respectively.

So while the florescent light in my example produces more UV light then visible light it's still more efficient due to the lack of heat loss.

In tool shops when tools were hardened or Tempered by heat the colour of temperature was identified and the tool dipped in water or the chemical for a time then again the colour indicated the temprature and dipped again.

With advancement of technology the temperature now is measured by Spectrometer.

The incandescent bulbs and Carbon rod Arc [was used in Cinema machines] are the source of white-light.

Of course these white colour sources are in efficient in convertion.

Regards

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The answer to this challenge will be posted later this month, right here on CR4.>

from 1st June to today. ?

Answer still not visible.

Reply to the challange still due.

Posted June 01, 2011 8:15 PM