抄録
Natrium-Sulfur energy storage system (NaS) is a new technology that provides load leveling. In this study, the electrical charge and discharge efficiency and other performance were computed from BMS data at Waseda Research Park Communication Center with a NaS system. Moreover, lost reduction effect by night shift and peak cut were calculated from the amount of charges and discharges. And the net present value was calculated based on the Discounted Cash Flow method.