This paper reviews the preliminary definition of integrated life support system configurations based on a single criterion decision-making task (SCDMT).
Comparative analysis results are shown for currently used effectiveness models based on SCDMT. Possible areas of application for those models are determined.
It is also proven that well-known effectiveness model, which uses an equivalent mass approach to determine system expenditures, can be used only in cases where useful effect from system operation is the same.
The article proposes the use of a global thermodynamic effectiveness criterion based on the exergy method to account for ECLSS functional expenditures, i.e. functional costs. Exergy is a concept that fuses energy and material quality information in a measure that is both descriptive and physically significant. This method accounts for nonequivalence of different forms of energy and allows measuring technological flows in the system using same measuring units. Technological flows is a general term, that includes all mass, power, data, etc. flows in the system.
The paper shows the results of single criteria evaluation of both biological and physical/chemical advanced ECLSS and points out the necessity to account for the uncertainty in initial information for accurate problem solution.