The Okawachi Pumped Storage Power Station (Japanese: 大河内発電所, Hepburn: Ōkawachi Hatsudensho) is a large pumped-storage hydroelectric power station in Kamikawa Town in the Kanzaki District of Hyōgo Prefecture, Japan.

With a total installed capacity of 1,280 megawatts (1,720,000 hp), it is one of the largest pumped-storage power stations in Japan.

[3] Like most pumped-storage facilities, the power station uses two reservoirs, releasing and pumping as the demand rises and falls.

[5][6] A second conventional hydroelectric power plant (南小田第二発電所, Minamioda Dai Ni Hatsudenjo) with a generation capacity of 720 kW was added in May 1919.

Two of the units are adjustable speed systems manufactured by Hitachi, allowing for a rapid variation of power levels during both pumping and generation.