How much lumens/amp for 100% efficiency?

[afahmic]

The LED's efficiency is annotated by lumens/amp. Then actually how much lumens/amp for 100% efficiency, and for the current LED efficiency (100 lumens/350 mA Luxeon Rebel), how much percentage of the efficiency by 100% scale?

 

[monkeyboy]

That's lumens/watt not lumens/amp.

It depends on the colour spectrum: For phosphor white LEDs about 250lm/w and about 400lm/w for the ideal RGB LED.

The most efficient phosphor white LEDs are around 100lm/w at the moment although efficiency decreases at higher drive currents.

 

[monkeyboy]

edit: double post

 

[afahmic]

Thanks for the info, monkeyboy.

Currently i have Fenix L2D Rebel 100. How much the efficiency of Rebel 100 in lumens/watt? Is it white phosphored or RGB LED type? What's the most efficient LED at this moment?

Sorry for asking such a foolish questions as i am still a newbie and should learn much more about LEDs and lights.

 

[monkeyboy]

I believe the rebel 100 is just under 100lm/w @ 350mA. Almost all white LEDs are the phosphor type (including the rebel). These are much more efficient at the moment but RGB will be capable of more in the future.

Most efficient LED at the moment is the cree R2 but the rebel 100 is about the same. You probably wouldn't be able to tell the difference.

 

[Gunner12]

Efficiency of a LED changes at different drive levels and also depends on heat.

A LED can have more the double efficiency at a low(Sub 50mA) drive level compared to a higher drive current(1 amp)

At 350 mA, the Cree R2 and rebel 100 are probably the most efficient. In your L2D-Rebel 100, I'm guessing a bit above 70 Lumen/Watt on turbo. More efficient at lower drive levels.

Almost all of the white LEDs you see now is a blue die yellow phosphor LED.

 

[AlanJ]

Percent energy efficiency

Currently i have Fenix L2D Rebel 100. How much the efficiency of Rebel 100 in lumens/watt? Is it white phosphored or RGB LED type? What's the most efficient LED at this moment?

Others have given you good answers for most of your questions, but there is still the matter of percent energy efficiency, and also efficiency at your L2D's four drive levels. To answer these questions, I'll use the graphs from evan9162's technical evaluations:
http://www.candlepowerforums.com/vb/showthread.php?t=178655

From the L2D's specified emitter lumens and evan9162's luminous flux graph, the L2D's drive levels should be approximately Low: 30 (extrapolated), Med: 150, High: 350, and Max: 700 milliamps. These correspond to efficiencies of Low: 130 (extrapolated), Med: 115, High: 100, and Max: 80 lumens per watt.

For percent energy efficiency, we need to know how many lumens there are in each emitted watt. I integrated the spectra from the Rebel datasheet (http://www.lumileds.com/pdfs/DS56.pdf) and came up with 325 +/- 10 lm/W. That gives us the answer to your original question: Low: 40%, Med: 35%, High: 31%, and Max: 25%.

 

[Handlobraesing]

The LED's efficiency is annotated by lumens/amp. Then actually how much lumens/amp for 100% efficiency, and for the current LED efficiency (100 lumens/350 mA Luxeon Rebel), how much percentage of the efficiency by 100% scale?

100% efficiency? Ain't gonna happen.