Study on optimum configuration of off-grid systems from the viewpoint of renewable energy ratio and investment cost

In this paper, the optimum configuration of DC off-grid systems from the viewpoint of renewable energy ratio and the installation cost has been studied. The DC off-grid system is assumed to consist of power loads for 50 three-person-households, solar panels and storage batteries installed in each house, an emergency power generator, and a DC bus-line that electrically connects them. The power flow of the DC off-grid system is numerically simulated over a period of one year and the renewable energy ratio and the installation cost is estimated. Based on the simulation, the optimal configuration and installation cost of the grid components required to achieve a given value of the renewable energy ratio has been derived.