system
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human
ELI5:what is cold fusion?

So i recently read an article where the term "cold fusion" was used, it was described as something that could provide 1500kilowatt out of 1 gram fuel?

Is this right?
And if so, would it be cheap enough that people would actually use it?
(Example: If fusion went out in the market people would probably still buy coal fueled energy since its significantly cheaper).
gpt
Fusion is an incredibly abundant source of energy, and we know it works because the Sun and hydrogen bombs are both powered by it.

Unfortunately, since it only seems to happen at absurdly hot temperatures -- easily hot enough to melt any material -- it is very hard to control.  (As opposed to nuclear fission reactors, which are made of metal and ordinarily do not melt.)

In 1989, some researchers announced that they had figured out how to make fusion happen at lower temperatures.  That would have been *huge*... had it worked.  Unfortunately, in their rush to be the first to announce such a groundbreaking discovery, they didn't check their work, and nobody could reproduce their results.  It ended some scientific careers.

Fusion research continues, but it's generally "hot fusion", which requires exotic things like giant magnets to contain the fusion reaction, which themselves consume a ton of electricity... they're still trying to figure out how to generate more electricity than they use in the process.

When people talk about "cold fusion", they're often not even talking about fusion at all, but rather about fraudulent technological claims that don't actually work.