exergy

"Available energy" redirects to this page. For a discussion about the meaning of the term in particle collisions, see Available energy (particle collision) Exergy is defined differently in different fields of study. In thermodynamics, exergy is defined as a measure of the actual potential of a system to do work. In systems energetics, exergy has been defined as entropy-free energy. The latter definition is also related to the negentropy concept which aims to measure the work performed by biological systems. It is unclear whether these definitions are equivalent.
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