In this paper, we target the specific smart grid concept called “Inter-Intelligent Renewable Energy Network (i-Rene)”, which is characteristically associated with PV panel, micro storage and regional electricity market. In this smart grid, every houses has an artificial intelligence agent which leans optimal treading strategy to minimise the payment of residents. From the economic standpoint, we take the cost-and-benefit-analysis (CBA) on the optimal installation of PV panels and micro storages in this smart grid. To take the CBA, we use actual measured values about power demand profiles and power production profiles which were obtained in 2010 at Shiga, Japan. In accordance with this analysis, we also discuss the necessary condition for achieving Grid parity of smart grid i-Rene.