Hydropower is one of the most mature, cost-effective, and clean renewable energy sources worldwide, yet its power generation output is inherently constrained by seasonal water flow changes, rainfall fluctuations, and river basin water scheduling rules. In rainy seasons, excessive water inflow leads to surplus hydropower generation, resulting in abandoned water and wasted clean energy resources. In dry seasons, reduced water volume sharply cuts power output, causing unstable power supply and difficulty in meeting the continuous grid power demand. The matching energy storage system serves as a critical regulating buffer for hydropower stations, effectively solving the intermittent and unstable shortcomings of traditional hydropower generation and improving the overall utilization efficiency of hydropower resources.

The supporting energy storage system operates through peak shaving and valley filling to coordinate with hydropower operation. During periods of sufficient water flow and low grid power load, the energy storage device absorbs and stores the excess electric energy generated by hydropower units that cannot be consumed by the grid. When the power grid enters peak power consumption periods or dry seasons with insufficient hydropower output, the stored electric energy is released to supplement the power supply. This bidirectional regulation mode balances the power output gap of hydropower stations, stabilizes grid voltage and frequency, and avoids power supply fluctuations caused by sudden changes in water flow. Moreover, energy storage can respond rapidly to grid dispatching instructions, realizing millisecond-level power regulation which makes up for the slow response defect of traditional hydropower unit mechanical regulation.

In addition to power regulation, supporting energy storage also enhances the grid connection capacity and operational economy of hydropower stations. With the large-scale integration of wind and solar renewable energy into the power grid, the grid has higher requirements for power supply stability. The combination of hydropower and energy storage forms a complementary clean power system, which can effectively resist the impact of fluctuating new energy power generation on the grid. It reduces the abandonment rate of hydropower, increases the effective power generation hours of hydropower units, and improves the economic benefits of hydropower projects. At the same time, this integrated mode optimizes the power supply structure, reduces the reliance on thermal power peaking, and further promotes the low-carbon and green development of the power industry.