Techno-economic performance analysis of zero energy house applications with home energy management system in Japan

Abstract

ZEHs are one of the main practices in current Japanese low carbon demonstration projects. ZEHs with wide implementation of HEMS are expected to provide energy and cost-saving chances and are playing more as prosumers under collaboratively designed power-pricing schemes. This research focused on investigating the techno-economic performance of real ZEH applications in Japan. Firstly, we introduced the current technological innovations and coordinated smart management strategies to optimize the cost or energy-saving performance of the ZEHs. Then, we illustrated the operational performances of four typical ZEHs focused on the power of self-sufficiency and dynamic power balance. Meanwhile, we examined the role of HEMS in managing integrated on-site generators based on how they operated according to historical data. Results indicated that day-ahead prediction helped enhance the matching scenario between daily thermal consumption and preproduction of heat pumps, fuel cells could respond effectively to changes in simultaneous electricity and heating loads, and cogeneration systems could enhance the local electricity self-sufficiency ratio and reduce net load fluctuations, especially under high heating demand periods. We also concluded that efficient performance of ZEHs is not just a matter of advanced technologies but is also highly dependent on real-time demand-side management and local load-matching scenarios. Finally, we analyzed and compared the impacts of integrated on-site generators among ZEHs on improving economic and environmental performance from an overall energy system. The analysis indicated that PV contributed to a significant ratio of annual ZEH's economic profit. Fuel cells presented an advantage in reducing annual CO2 emission.