Optimization of design parameters of a net zero energy home

Abstract

A simple model for a detached house in Beirut is optimized using a building energy simulation program to minimize two objective functions: the annual thermal demand; and the difference between the total electrical load and the on-site electricity generated from the renewable energy system. The optimization variables are: insulation thickness of external walls and roof, thickness of roof reinforced concrete, size of windows on each façade, number of solar collectors of the domestic hot water system (SDHW), SDHW circulating pump flow rate, and number of panels of the Photovoltaic system (PV). The main optimization constraint adopted is the thermal comfort criterion. Results of the optimization shows that the exclusion of cost parameter may lead to unfeasible solutions even if the net zero balance is theoretically achieved.