Development and Prospect of the Pumped Hydro Energy Stations in China

Abstract

Pumped hydro energy storage (PHES) has been recognized as the only widely adopted utility-scale electricity storage technology in the world. It is able to play an important role in load regulation, frequency and phase modulation and black starts in power systems. Due to its outstanding functions, this technology has been widely used worldwide.This paper introduces PHES including its functions and the technologies briefly to supply a comprehensive cognition of this technology. The key technologies of PHES, such as design and manufacture of reversible pump-turbine runners, design of heavy-duty thrust bearings and shaft sealings, startup of unit etc., are important for the PHES. In addition, more and more new technologies, such as operation with seawater, underground lower reservoirs, adjustable speed units etc., were put forward and used in PHES to make it perform better.This paper focuses on the development of PHES in China. Thanks to a rapid development of China’s economy in the recent years, PHES has gained a fast development. At present, China has owned the biggest installed capacity (29.9 GW by the end of 2018) of PHES the world. PHES has been an indispensable part of the power grid to increase the stability of the grid and improve the penetration of sustainable energy such as wind power, solar energy etc. With the employment of new technologies. China’s new PHES stations, such as Guangzhou, Tianhuangping, Xilongchi PEHS etc., have become the representatives of the world’s most advanced level. Based on the requirement of the current power grid for PHES, some new PHES have been under construction and more PHES are in the planning and design stage.