The unconventional solution model of Mobile Order, which has previously been shown to provide a very accurate thermodynamic description of anthracene solubilities and chemical potentials in binary hydrocarbon + alcohol solvent mixtures, is extended to other thermodynamic excess properties. An expression is derived for predicting excess molar enthalpies of ternary alcohol + two inert hydrocarbon systems from measured binary data. Applications and limitations of the newly derived predictive expression are assessed using published enthalpy data for ternary ethanol + n-hexane + n-decane, ethanol + n-hexane + n-dodecane, 1-propanol + n-hexane + n-decane and 1-propanol + n-hexane + n-dodecane systems.