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[on:]

http://www.wired.co.uk/news/archive/2012-03/09/230-percent-efficient-leds

More Light out, than electricity you put in.... 

Going by the date, it's an old article, there has to be some news about their latest developments...

[Reply #1 on:]

Wow.... light up the room and cool it down at the same time!

[Reply #2 on:]

I bet people still won't use resistors with them...

[Reply #3 on:]

Can we all look forward to brightly lit, led-lined fridges and freezers. :-)

[Reply #4 on:]

I bet people still won't use resistors with them...

[Reply #5 on:]

This is the LED as heatpump - or "light-emitting fridge" (!)

Basically turning heat into light increases entropy, so its thermodynamically favorable, in a pn-junction the electron flow
is coupled to this heat->light conversion and thus it is current-controlled.

Compare to a peltier device...

[Reply #6 on:]

Basically turning heat into light increases entropy, so its thermodynamically favorable

Aaaaargh..... the E-word.... Now I remember why I hated undergrad thermo classes

[Reply #7 on:]

Wow! Does anyone know if, when, or where you can get these?

[Reply #8 on:]

What would you do with one.
Produces 69 picowatts of light.
Not much you can do with that, let alone see that it was on.

[Reply #9 on:]

What would you do with one.
Produces 69 picowatts of light.
Not much you can do with that, let alone see that it was on.

Because of this possibility :

Going by the date, it's an old article, there has to be some news about their latest developments...

[Reply #10 on:]

Something is not right...

LEDs light output are measured in lumens...

Kinda odd the scientists used "watts" to measure the light output. What gives?

[Reply #11 on:]

Kinda odd the scientists used "watts" to measure the light output

Well light is energy (Joules) in its own right and the rate at which energy is produced or consumed is power (Joules / second = Watts).

Produces 69 picowatts of light....Not much you can do with that

Yeah, you'll need a shed load of the things to be able to read the newspaper, let alone keep the drinks cold.....

[Reply #12 on:]

Well, a toaster can consume 150watts of energy so I guess the glow from it's heating coils is 150 watts of light output also.

You know what I mean? 

[Reply #13 on:]

lumens isnt a very good measure of output since it is a measure of how human eyes can see it, so something that small would probably be less than a lumen, but for example look at infrared leds, they are measured in the same way since you cant see the infrared so technicaly you can have a 10W infrared-led and feel the heat a foot away and yet it will be outputting <1lumen

[Reply #14 on:]

150watts of energy

Watts are power, not energy....