An Operating Method and Economic Estimation of Grid-connected Residential Photovoltaic Systems with Battery

Abstract

The increased renewable energy utilization, especially photovoltaics using solar energy, has been expected in recent years because of the limited available fossil energy and the environmental impacts due to its consumption. The deregulation in the Japanese power industry allows transmission of surplus PV power from housing to the power grid and PV system utilization becomes more attractive. However, so for as authors know, there are few publications which analyze the economic value of the grid-connected PV system for domestic building considering running cost.
In this paper, we firstly present an operating and control algorithm for the grid-connected PV system with battery and define an economic benefit obtained through system operation. We also, define the equalized PV power generation cost considering both investment and operation costs so that we can make clear the economic effect of the amount of power generated by PV on the equalized PV power generation cost. Secondly, we show an critical condition obtained from economic view point by which we determine the critical battery capacity to be installed as power storage equipment. Finally, through numerical examples of a yearly operation of a model PV systems, we ascertain the effectiveness of the proposed approach.