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What is exergy? The one time a mechanical engineering colleagues tried to explain it to me, he reached the wrong conclusion on the problem we were working on.

I haven't seen it in any physics thermodynamics book, and only mech eng. seem to know what it is, and then only in the US.

Faires (undergrad MIT Thermo book from the 50s) makes no mention of it as far as I can tell.

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@tlocke

But that isn't a mathematical expression. At best, it would appear to be energy * maximum_Carnot_efficiency (for heat engines anyway)

But it seems not to be adding very much, since Carnot efficiency depends on delta_(T). The OPs point that exergy doesn't depend on T is tautological since T has already been accounted for by the Carnot expression.

Exergy is the amount of work that a system can potentially do. It was on my physics course in the UK I'm fairly sure.

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