Economic Solution of the Tri-Generation System Using Photovoltaic-Thermal and Ground Source Heat Pump for Zero Energy Building (ZEB) Realization

The zero energy building (ZEB) is being introduced as a new energy policy in the building sector. Accordingly, to realize the ZEB, renewable energy systems that can produce energy are essential. Various hybrid systems are being proposed to develop a more efficient system than individual renewable energy systems, among which tri-generation systems are attracting attention. In this study, in order to find an economic solution of a tri-generation system for the realization of ZEB, the simulation model using the dynamic energy analysis code was constructed and a feasibility study was conducted. Moreover, the conventional design method and the design method for ZEB realization were proposed, and the return on investment (ROI) was calculated according to four local conditions and two design methods. As a result of energy analysis, the energy self-sufficiency (ES) in Seoul, Ulsan, Ottawa and Toronto were calculated as 62%, 65.1%, 57.7%, and 60.2%, respectively. Moreover, results of feasibility analysis compared to a conventional system showed that the payback period of the tri-generation system in South Korea was within 13 years, and Canada was within 10 years.