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Led knowledge

Will led save or not ? part 2: Led luminous efficiency.

LED Lamps have 7 times light emitted than incandescent lamp.
If you’re not sure which one will be better chosen when you try to replace your home lighting, the easiest way just remembers 3W Led lamp equivalent to 20W incandescent lamp.

3w-led-lamp-and-25w-of-halogen

Days ago we had a quick though about the life span of the LED lighting and normal lighting in the house.
Remember the three ways of saving?
First, average life span;
Second, luminous efficiency;
Third, average power use.

Today we are going on to the second topic:
luminous efficiency.

Of course we start from the most common lamp, incandescent (and halogen, they are same way of emitting.)
It is easily understood that incandescent / halogen lamps are light out by burning the tungsten inside, it is like a fire, besides emitting light, more power consumed as heat.
Guess how much it will be? 90%! That means only 10% of power become visible light. Aha, It is a good choice for warm your house.

As Energy Star determined efficacy by the following equation:
Efficacy [Lumens per Watt]=(Measured Lamp Lumens [Lumens])/(Measured Input Power [Watts])

Average of a 20W incandescent can make about 200-300 lumens
That means the efficacy of incandescent will be 10-15 Lumens per Watt (LPW)

CFLs are much better. 200-300 lumens required one piece of 5W CFLs (compact fluorescent lights)
It is about 40-50 LPW.

And LED lamps, Just 3W, it can have the efficacy higher than 70-80 LPW. And some of the leader of light-emitting diodes manufactories, such as CREE, already high efficacy (up to 100 Lumens Per Watt)

Now it is clear that, under the same level of emitting light at about 200-300 lumens, requires:
3W LED lamp or 5W compact fluorescent light or 20W incandescent lamp.

As what I said at the very beginning, if you are not sure which one will be better choose when you try to replace your home lighting, the easiest way is just remember 3W Led lamp equivalent to 20W incandescent lamp.

Hope it will help.
If you disagree with us or have any more questions about LED, we will be glad to have your idea.
Best regards and have a wonderful day.
Yours
Keith Othman

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About Keith Othman

Small businessman

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