On the energy, exergy and cost optimisation of multi-energy-carrier power systems

Abstract

This paper introduces the exergy hub approach, a framework that can be used for the optimisation of multi–carrier energy supply systems. Moreover, this paper presents a comparison between the results of the optimal dispatch (which defines how much power should be produced by each generation unit) obtained from an exergetic efficiency optimisation and the optimal dispatch obtained from an energetic efficiency optimisation. Finally, a scheduling optimisation (which defines when to turn on or turn off a unit) is performed to identify which combination of available units gives the best exergy and energy performance for different load ratios according to the outside temperature. The results provide valuable insights about the influence of using exergy analysis as an assessment tool in the optimisation of energy supply systems with multiple energy carriers, particularly regarding the difference with respect to an energy optimisation and the effect of the outside temperature.