LED's for Home Lighting

Are you interested in transforming your home lighting from CFL's to LED's

  • Yes, will look forward to it.

    Votes: 22 41.5%
  • Yes, I'm interested, but the prices are prohibitive.

    Votes: 27 50.9%
  • Don't know, as I don't have an idea as which one is better.

    Votes: 3 5.7%
  • No. I'm better off with CFL's.

    Votes: 1 1.9%

  • Total voters
    53
  • Poll closed .

CyberKID

In search for Tech Gyan!
LED's for Home Lighting

Introduction to LED's
Excerpts taken from wikipedia
A light-emitting diode (LED) is a semiconductor light source. LEDs are used as indicator lamps in many devices and are increasingly used for other lighting. Appearing as practical electronic components in 1962, early LEDs emitted low-intensity red light, but modern versions are available across the visible, ultraviolet, and infrared wavelengths, with very high brightness. Light-emitting diodes are used in applications as diverse as aviation lighting, automotive lighting, advertising, general lighting, and traffic signals. LEDs have allowed new text, video displays, and sensors to be developed, while their high switching rates are also useful in advanced communications technology. Infrared LEDs are also used in the remote control units of many commercial products including televisions, DVD players, and other domestic appliances.
Wikipedia Link: Light-emitting diode - Wikipedia, the free encyclopedia
In simple terms, LED's are simple devices made up of semiconductors which emit light when electricity is applied to them. LED's or Light Emitting Diodes are becoming extremely popular owing to their extremely low power consumption, bright light, and longer life. Till a few years back, LED's were being used in Avionics, such as beacons, landing guidance lights, etc, but, the advances in the LED technology and drastically reduced prices have made them extremely popular for other applications. Most of us would have seen the LED's are fast replacing the buggy old signals on roads and railway lines. This is because of extremely compact design, high durability and higher light intensity adding to higher visibility and power efficiency the LED technology has provided us.

Basic Design of an LED

*www.off-road.com/aimages/articlestandard/trucks4x4/242009/603132/LED-labelled.jpg

Shapes and sizes in which LED's are available

*upload.wikimedia.org/wikipedia/commons/thumb/9/9e/Verschiedene_LEDs.jpg/640px-Verschiedene_LEDs.jpg*linova.cn/upfile/hpledcomp/DGL-100-W.jpg*linova.cn/upfile/ledcomp/5050w.jpg*linova.cn/upfile/hpledcomp/1-3W.jpg*linova.cn/upfile/hpledcomp/1-3WnoBase.jpg

Various Colours Available in LED's and the Semiconductor Materials Used in Producing Them

Conventional LEDs are made from a variety of inorganic semiconductor materials. The following table shows the available colors with wavelength range, voltage drop and material:
ColorWavelength [nm]Voltage drop [ΔV]Semiconductor material
Infraredλ > 760ΔV < 1.63Gallium arsenide (GaAs)
Aluminium gallium arsenide (AlGaAs)
Red610 < λ < 7601.63 < ΔV < 2.03Aluminium gallium arsenide (AlGaAs)
Gallium arsenide phosphide (GaAsP)
Aluminium gallium indium phosphide (AlGaInP)
Gallium(III) phosphide (GaP)
Orange590 < λ < 6102.03 < ΔV < 2.10Gallium arsenide phosphide (GaAsP)
Aluminium gallium indium phosphide (AlGaInP)
Gallium(III) phosphide (GaP)
Yellow570 < λ < 5902.10 < ΔV < 2.18Gallium arsenide phosphide (GaAsP)
Aluminium gallium indium phosphide (AlGaInP)
Gallium(III) phosphide (GaP)
Green500 < λ < 5701.9[SUP][55][/SUP] < ΔV < 4.0Indium gallium nitride (InGaN) / Gallium(III) nitride (GaN)
Gallium(III) phosphide (GaP)
Aluminium gallium indium phosphide (AlGaInP)
Aluminium gallium phosphide (AlGaP)
Blue450 < λ < 5002.48 < ΔV < 3.7Zinc selenide (ZnSe)
Indium gallium nitride (InGaN)
Silicon carbide (SiC) as substrate
Silicon (Si) as substrate — under development
Violet400 < λ < 4502.76 < ΔV < 4.0Indium gallium nitride (InGaN)
Purplemultiple types2.48 < ΔV < 3.7Dual blue/red LEDs,
blue with red phosphor,
or white with purple plastic
Ultravioletλ < 4003.1 < ΔV < 4.4Diamond (235 nm)[SUP][56][/SUP]
Boron nitride (215 nm)[SUP][57][/SUP][SUP][58][/SUP]
Aluminium nitride (AlN) (210 nm)[SUP][59][/SUP]
Aluminium gallium nitride (AlGaN)
Aluminium gallium indium nitride (AlGaInN) — down to 210 nm[SUP][60][/SUP]
Pinkmultiple typesΔV ~ 3.3[SUP][61][/SUP]Blue with one or two phosphor layers:
yellow with red, orange or pink phosphor added afterwards,
or white with pink pigment or dye.[SUP][62][/SUP]
WhiteBroad spectrumΔV = 3.5Blue/UV diode with yellow phosphor
From Wikipedia

The beauty of LED's is that they are extremely compact, very power efficient and in the recent times, have become almost dirt cheap. Those who have some experience of working with electronics components and soldering can easily make an LED light with some cheap components and some LED's from any local electronics components store. However, for those who don't have any experience in working with electronics components and soldering, well, they can try working on with some simple circuit designs with less number of components. And at last, those who don't want to get their hands dirty buying components and putting up a circuit to power up the LED's can simply buy LED's and LED drivers and just connect the LED's to these drivers or simply go and buy LED lamps. Though, they are costly, but will simply save you the cost difference between the CFL's and the LED lamps within one year.
For those living in Delhi, BSES is offering (selling on subsidy) upto 4 LED lamps per bill. You can go and get one of these. *articles.timesofindia.indiatimes.c...8089_1_leds-cfls-and-incandescent-bulbs-light

Comparision Between LED, Incandescent and Compact Fluorescent Lamps

Source: www.designrecycleinc.com
Comparison Chart
LED Lights vs. Incandescent Light Bulbs vs. CFLs
Energy Efficiency
& Energy Costs

*www.designrecycleinc.com/A1304-Pearlled-1.jpg
Light Emitting Diodes (LEDs)

*www.designrecycleinc.com/INBulb.jpg
Incandescent
Light Bulbs

*www.designrecycleinc.com/CFL.jpg
Compact Fluorescents (CFLs)
Life Span (average)
50,000 hours
1,200 hours
8,000 hours
Watts of electricity used
(equivalent to 60 watt bulb).

LEDs use less power (watts) per unit of light generated (lumens). LEDs help reduce greenhouse gas emissions from power plants and lower electric bills
6 - 8 watts
60 watts
13-15 watts
Kilo-watts of Electricity used
(30 Incandescent Bulbs per year equivalent)
329 KWh/yr.
3285 KWh/yr.
767 KWh/yr.
Annual Operating Cost
(30 Incandescent Bulbs per year equivalent)
$32.85/year
$328.59/year
$76.65/year
Environmental
Impact
*www.designrecycleinc.com/pearlled_30-h60.JPG
Light Emitting Diodes (LEDs)

*www.designrecycleinc.com/INBulb.jpg
Incandescent
Light Bulbs

*www.designrecycleinc.com/CFL.jpg
Compact Fluorescents (CFLs)
Contains the TOXIC Mercury
No
No
Yes - Mercury is very toxic to your health and the environment
RoHS Compliant
Yes
Yes
No - contains 1mg-5mg of Mercury and is a major risk to the environment
Carbon Dioxide Emissions
(30 bulbs per year)

Lower energy consumption decreases: CO2 emissions, sulfur oxide, and high-level nuclear waste.
451 pounds/year
4500 pounds/year
1051 pounds/year
Important Facts
*www.designrecycleinc.com/pearlled_30-h60.JPG
Light Emitting Diodes (LEDs)

*www.designrecycleinc.com/INBulb.jpg
Incandescent
Light Bulbs

*www.designrecycleinc.com/CFL.jpg
Compact Fluorescents (CFLs)
Sensitivity to low temperatures
None
Some
Yes - may not work under negative 10 degrees Fahrenheit or over 120 degrees Fahrenheit
Sensitive to humidity
No
Some
Yes
On/off Cycling
Switching a CFL on/off quickly, in a closet for instance, may decrease the lifespan of the bulb.
No Effect
Some
Yes - can reduce lifespan drastically
Turns on instantly
Yes
Yes
No - takes time to warm up
Durability
Very Durable - LEDs can handle jarring and bumping
Not Very Durable - glass or filament can break easily
Not Very Durable - glass can break easily
Heat Emitted
3.4 btu's/hour
85 btu's/hour
30 btu's/hour
Failure Modes
Not typical
Some
Yes - may catch on fire, smoke, or omit an odor
Light Output
*www.designrecycleinc.com/A1304-Pearlled-1.jpg
Light Emitting Diodes (LEDs)

*www.designrecycleinc.com/INBulb.jpg
Incandescent
Light Bulbs

*www.designrecycleinc.com/CFL.jpg
Compact Fluorescents (CFLs)
Lumens
Watts
Watts
Watts
450
4-5
40
9-13
800
6-8
60
13-15
1,100
9-13
75
18-25
1,600
16-20
100
23-30
2,600
25-28
150
30-55
Link: *www.designrecycleinc.com/led comp chart.html
 

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icebags

Technomancer
nice LED thread. *l.yimg.com/us.yimg.com/i/mesg/emoticons7/41.gif

i will post my last dialogue again:

if u guys are looking for these 1 watt LEDs for power saving, the drivers, if transformer based, (read ac adapters) have energy efficiency in the range of 20-75%.

that is, to deliver 1 watt to the LED, it may draw from 1.33W to 5W from wall.

however, if drivers are just resistance based, its different.
 
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OP
CyberKID

CyberKID

In search for Tech Gyan!
From Post Your Latest Purchase Thread
if u guys are looking for these 1 watt LEDs for power saving, then let me tell u, the drivers, if transformer based, (read ac adapters) have energy efficiency in the range of 20-75%.

that is, to deliver 1 watt to the LED, it may draw from 1.33W to 5W from wall. :lol:

however, if they are just resistance based, its different.

I think when we are considering energy efficient lighting, we can't make use of ordinary step down transformers as these are not that energy efficient and using one might, well, negate the energy efficiency you're getting by using LED's. Buying efficient transformers is a tricky job as first of all you'll not get them so easily and even if you find them, you'll have to pay too much. By efficient transformers, I mean to say the kind of AC step down transformers that have a comparatively better build quality with high quality copper or aluminium winding and well designed core.
 

icebags

Technomancer
PLEASE DON'T TRY AT HOME

use of main 220 - 240V AC as per the following circuit diagram will result in wayyyy better efficiency (i m guessing 60% - 90% or more), it will depend a lot on the quality of capacitor C1.

also, efficiency is like : input power = circuit flow power + circuit generated heat.

its a diagram for 0.5 watt (total) LED lighting. but to drive four 1 watt LEDs , replace the R2 with 240-250 ohm 1W resistance. all parts are very important and should not be altered without prompt knowledge. also don't forget to protect the circuit with proper ventilated case with proper insulation. and don't touch it, while its working or even after switching off because of the charge holding capacitor :eeek:.

CX is not normal capacitor, its X rated capacitor, and 472K is not its pico farad value.

to read full article, click the image.

*electroschematics.com/wp-content/uploads/2009/11/clip_image00210.gif
 
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OP
CyberKID

CyberKID

In search for Tech Gyan!
Ok, will post the one my brother designed specifically for driving 8 mm LED's in the evening.

use of main 220 - 240V AC as per the following circuit diagram will result in wayyyy better efficiency (i m guessing 60% - 90% or more), it will depend a lot on the quality of capacitor C1.

also, efficiency is like : input power = circuit flow power + circuit generated heat.

its a diagram for 0.5 watt (total) LED lighting. but to drive an 1 watt LED, replace the R2 with 240-250 ohm 1W resistance. all parts are very important and should not be altered without prompt knowledge. also don't forget to protect the circuit with proper ventilated case with proper insulation. and don't touch it, while its working :-D.

to read full article, click the image.

*electroschematics.com/wp-content/uploads/2009/11/clip_image00210.gif
Those, who don't have some knowledge of electronics and soldering, PLEASE DON'T TRY AT HOME.
Even after unplugging the circuit, don't touch the circuit before you short circuit both the terminals (marked P and N) of the wire leading to mains using an metallic piece, as such a circuit tends to store some power and may give you a lethal shock.
 

icebags

Technomancer
^^ thanks for the warning, much appreciated. :)

Even after unplugging the circuit, don't touch the circuit before you short circuit both the terminals (marked P and N) of the wire leading to mains using an metallic piece, as such a circuit tends to store some power and may give you a lethal shock.

R1 is for that purpose. But it will take some time to discharge the capacitor. So shorting P & N is not required, just leave the circuit alone and it will discharge itself.
 
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sjoardar

Go Ahead, Make My Day!
@ sjoardar, d6bmg, NIGHTMARE, ajayritik, icebags : I think we should continue the LED discussions is this thread and shouldn't clutter the Post Your Latest Purchase thread with our LED discussions.

You are right! I kinda got carried away! Your new thread is really great and very informative.

Guys even I was looking for these LED Tube lights. These are available in electronic shops here in Hyderabad and also available with the footpath vendor. So you guys saying these are not reliable? I need 3-4 of these. Which ones should I go for? I see Cyberkid suggesting some expensive ones. Can I have the link for these. Also any link in ebay for these?

I need these in case of powercuts as backup.

Well, we're saying such and such items are not available in Kolkata! In case you do not already know, the Kolkata market is one of the most backward in the country. Easily available here are only the low-end stuff. If one wants any high-end or nu-tech stuff, one usually has to hunt, wait and 'pray' for months here.:cry:
 
OP
CyberKID

CyberKID

In search for Tech Gyan!
So, here is the circuit my brother designed for 8mm LED's.
This is a simple circuit using cheap easy to available components, which can be sourced from any electronics repair shop.

*i.imgur.com/fnICI.png

The maximum cost of this circuit including all the components might not be more than Rs. 40 and if you get yourself General Purpose PCB's to easily mount all the components, then it might cost you around Rs. 16-20 for a 4x6 inch PCB, but this will easily accommodate all your components and working on it will be a lot easier.

Informative thread.... But how to replace these with CFLs ? :chinstrach:
Good question.
For replacing the CFL's we need to move up towards the UltraBright LED's, which are somewhat expensive than the regular 5mm LED's.
We'll be discussing that too a bit later in this thread.
 
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tomys24

Broken In
why is the 1 watt led has a big heat sink? it seems it will heat a lot. how much watt/energy is wasted as heat ?
 

ajayritik

Technomancer
Sorry guys for not being a techie even though I'm from Electronics Background. So I was checking if there is any good LED Light thing available in market currently which I can use as back up when my power goes out.
 

icebags

Technomancer
@ajayritik
u want to battery power LED ?

@CyberKID
u still want to add a 480k resistor across CX, if u want to discharge it automatically after switching off. :-D and good job with the zener.
 
OP
CyberKID

CyberKID

In search for Tech Gyan!
why is the 1 watt led has a big heat sink? it seems it will heat a lot. how much watt/energy is wasted as heat ?
Yes, it generates quite a lot of heat. That's why it has large aluminium heatsinks. As far as the energy wasted is concerned, the total consumption of the LED is concerned, if it's rated 1 watt, it's 1 watt.

@CyberKID
u still want to add a 480k resistor across CX, if u want to discharge it automatically after switching off. :-D and good job with the zener.
Good suggestion. Will give it a try. Though, it gradually gets discharged as the stored up energy is consumed by the LED's, which takes time. I never bothered about this as this gives a different effect to the LED lamp as when you switch it on, it glows instantly, but when you switch it off, it goes off slowly, giving you some time before the light goes off.
 

icebags

Technomancer
^^ well, slow going off is the electrolytic's doing more the mf value, longer the led stays on after switch off. CX circuit breaks the moment u switch off main AC. purpose of CX is voltage dripping from 220V ac to something like 12V AC.
 
OP
CyberKID

CyberKID

In search for Tech Gyan!
hmmm. you're right. I just forgot that I sometimes increase the value of the capacitor to make the LED's glow longer.
 

d6bmg

BMG ftw!!
I'm going to input my knowledge & works with LEDs in few weeks. Presently occupied with some exams.
BTW, very good initial guide. ;)
 
OP
CyberKID

CyberKID

In search for Tech Gyan!
^ Looking forward for that. Will be helpful for all of us.
BTW, All the best for your exams.
 
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