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0 pointslegulere9y ago0 comments

In fact because of thermodynamics over 100% efficient LEDs are possible. This was practically demonstrated some years ago: https://phys.org/news/2012-03-efficiency.html

Converting light to electricity on the other hand cannot reach 100% efficiency.

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ejolto9y ago· 1 in thread

It needs to be pointed out that the diode isn't converting over 100% of the electrical power into optical power. The extra optical power comes from Peltier heat drawn from the semiconductor lattice. The LEDs only had ">100% efficiency" when heated to 135°C. At 25°C the electrical efficiency was less than 1%.[1]

[1] Fig 1 (a) https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.108.097...

contravariant9y ago

That still counts. Ambient temperature and pressure are necessary for just about any 'engine'. In fact, extracting heat from the environment to do something useful is more impressive than just converting one form of energy into another.

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