A two-step approach for cost-effective design analysis of Net Zero Energy Homes

Net Zero Energy Homes (NZEHs) have emerged as the solution to achieve sustainable house design. However, an NZEH entails higher capital cost compared with that of a conventional home, which comprises the main barrier for promoting NZEHs. In addressing this issue and promoting the cost-effective design of NZEHs, a two-step cost analysis framework with a mathematical model is proposed in this research: (1) qualified NZEH design scenarios are selected based on energy simulation, monitoring, and the acceptance as an NZEH in terms of energy balance; and (2) cost performance is analyzed for these qualified NZEH design scenarios, based on which the cost-effective design scenario is identified for an NZEH. Through the innovative two-step cost analysis with the optimization model, the cost-effective scenario is identified for NZEH design, while the identified design scenario also meets net-zero energy requirements. The proposed research framework with the mathematical model is demonstrated using an NZEH in Edmonton, Canada, as an example, and a capital cost savings of 4.2% is achieved by applying the proposed two-step approach in this research. This paper proposes a generic approach for the cost-effective design of NZEHs, and the research results contribute to the promotion of the NZEH application.