Energy storage is the process of converting electricity into other forms of energy and storing them in a physical system, and then releasing them when needed. At present, many kinds of energy storage technologies have been developed, which can be categorized into three main types according to the energy conversion method, such as "physical", "electromagnetic" and "electrochemical", and the characteristics of each technology are listed in Table 1. Pumped hydro is one of the "physical" types of energy storage, and is currently the most mature and lowest-cost energy storage technology; since the first pumped hydro station was set up in Zurich, Switzerland in 1882, there has been more than a hundred years of application history. It must be set up in a location with an abundant and stable supply of water, but in recent years a number of new reservoirs facing ecological and environmental controversies and has been shelved, resulting in the global pumped storage power storage facilities since 2016, the volume of construction has only grown by 0.6%, compared to the annual growth rate of global power storage facilities reached 9%, pumped storage power, although it still accounts for the highest proportion of power storage, but the market share has been declining year by year, and the share of the first time in 2021 will be lower than the proportion of the first time. In 2021, the share of pumped storage power will be lower than 90% for the first time.