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Commander Kinsey Commander Kinsey is offline
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Default Why do LEDs generate heat?

On Thu, 03 Oct 2019 15:01:34 +0100, whisky-dave wrote:

On Thursday, 3 October 2019 14:49:47 UTC+1, Commander Kinsey wrote:
On Thu, 03 Oct 2019 14:29:30 +0100, Commander Kinsey wrote:

Why do LEDs generate heat? I want a technical answer not "because they're inefficient". And will we ever make them more efficient?


I got useful answers from Quora:

"LEDs are ever more and more efficient. In the last 40 years, tremendous strides have been made. They generate heat because they are conducting electricity through semiconductors. Unlike metals which have very little resistance to electric currents, semiconductors offer more resistance. Not as much as true nonmetals, but still more than metals. It is the resistance of the semiconductor layers, both N and P, and the resistance of the junction itself, that generate the heat."


pretty much what I"ve just said. without Quora.


The answers I pasted were far more detailed. I did say I wanted a technical answer.

"Every electronic device is less than 100 percent efficient. On a low level, it is due to the law of probability, or as the physicists call it, entropy. The odds of all those electrons conveying their energy into photons is very low. Some are always making random transitions, generating heat instead of light."