Exergetic ecological index as a new exergetic indicator and an application for the heat engines

Aim of this paper is to present a new exergetic index. This index is called exergetic ecological index and it is adopted from the ecological function that provides opportunity to compare power output (desired output) and exergy destruction (lost power). The bigger ecological function means the more efficient and environmental friendly energy system. However, this criterion does not give any information about relation with the exergy source and exergetic ecological index provides this comparison. Finally, exergetic ecological function includes product exergy, exergy destruction and exergy source in a one equation and enables to evaluate any energy system considering with these three parameter.