Overall review of pumped-hydro energy storage in China: Status quo, operation mechanism and policy barriers

With the integration of increased variable renewable energy generation and advent of liberalized electricity market, much attention has been devoted on the development of pumped hydro energy storage (PHES) as it has many prominent advantages of ensuring the safe and steady operation of power grid. In China, PHES has met a booming periods for the last ten years. Currently, there are 24 PHES stations with an installed capacity of 16.95GW while government's target of 2020 is 50.02GW. In this paper we provide an overall review of China's PHES development with a detailed presentation of the installed capacity and distribution of existing and proposed PHES stations, examine 4 typical stations in order to give a good description for the practical functions of PHES in power grid, analyze the management mode and price mechanism of PHES operation and point out the barriers in PHES development in China. State Grid Corporation of China (SGCC), which are making great efforts on China's PHES development, is discussed as a role model. On that basis we suggest PHES in the fast developing period should be temporarily operated and scheduled by grid companies in terms of exertion of its positive effects, while government should also take responsibility to subsidize on the stations' operation to relieve the price pressure of the ever-growing integration of renewable energy.