Finite-time thermodynamics: Exergy and optimization of time-constrained processes

The criterion of thermodynamic ideality is introduced. It is the ratio of actual rate of entropy production to the minimal rate of entropy production. It is closely related to the exergy approach but incorporates the irreversible losses due to finite-time and nonzero rates. No explicit reference need be made to the average values of the thermodynamic potentials of the environment. The regimes with minimal entropy production for the system where chemical reaction occurs and for the set of parallel heat engines are found.