Study on optimal configuration and ecological benefits of the Heishanxia hydro-wind-solar-pumped storage complementary system

In addition to conventional functions like flood control and water supply， hydropower projects can also promote the high-quality development and utilization of wind and solar energy while supporting regional ecological conservation. The Ordos Loop of the Yellow River is rich in wind and solar resources； however， the lack of flexible regulation capacity has limited the development and utilization of these resources in the area. Additionally， coal mining and thermal power plant operations in the region have intensified ecological pressure. This study analyzes the key role of the Heishanxia hydropower project （planned installed capacity of 2000 MW） in facilitating the exploitation of wind and solar energy within the Ordos Loop. The results indicate that the Heishanxia hydropower project， integrated with a pumped storage hydropower plant with planned installed capacity of 3000 MW， can support the development of wind and solar energy at 1.89 times its own capacity （3716 MW of wind power and 5760 MW of solar power） under a conventional baseload-inclusive operation mode. Under a flexible operation mode without baseload requirements， it can support 2.02 times its own installed capacity （4212 MW of wind power and 5888 MW of solar power）. Compared with the conventional operation mode， the flexible operation mode increases power generation benefits by 7.12%. Furthermore， the 5888 MW photovoltaic power plant， built based on the Heishanxia hydropower project， can significantly promote vegetation restoration in the region， increasing the net primary productivity of vegetation by 18.31×108 g dry matter annually （equivalent to reducing CO2 emissions from 1093 t of standard coal）. The analysis demonstrates that the Heishanxia hydropower project will play a dual role in facilitating the transition to clean energy and enhancing ecological conservation， holding significant importance for promoting ecological protection and high-quality development in the Yellow River Basin.