A new cost optimization algorithm has been developed as robust tool for engineers with the objective of designing cost-effective heating and cooling systems with low-enthalpy energy resources. Three modules for minimum combined life-cycle cost were prepared, which involve the analysis of conventional terminal units, panel systems, and hybrid HVAC systems, for steady-state conditions. In the first module, the operating temperature of the hydronic system is optimized. In the second module, panel tube spacing is optimized. This module also calculates the optimum design values for the average operating liquid temperature, tube diameter, and heat pump size. The third module is a combination of the first two modules such that the split of sensible space conditioning load between the conventional terminal units and panel systems is optimized. In this paper, the formulation of the optimization algorithm is explained with a design example and parametric results are given to establish a general insight into the relative importance of several design factors.

Units: SI