ThermoEconomics, a design tool for the next century

Thermoeconomics is the combination of thermodynamics using exergy with economics. The objective of thermoeconomics is to minimise a total cost function, which includes capital, maintenance and running costs. This will establish the most cost effective, or optimal, design parameters. This paper shows the application of thermoeconomic analysis to a building services system, consisting of a constant air volume (CAV) air conditioning system. The specific cost of indoor environment cooling is optimised in terms of system variables, such as water and air temperatures and mass flow rates. The method is firstly to determine the most significant variables from the detailed exergy analysis. Secondly, the process may be optimised by implementing the most appropriate design modifications. From the work presented, significant and unexpected improvements to both thermal and economic design are made.