Overview of China's hydropower absorption: evolution, problems, and suggested solutions

摘要

China has experienced an unprecedented increase in hydropower development with the implementation of the 'West-East Electricity Transfer' project. Its total hydropower capacity has reached 350 GW, of which nearly one-third is transmitted to the load centre through an ultra-high-voltage power network. However, the absorption of abundant hydropower in southwest China is still a challenge, with increasing hydropower curtailment each year. This study provides an overview of the evolution of hydropower absorption, analyses the major problems and possible causes, and suggests several technical solutions. It is suggested to optimise the generation operations with power network limitations and transmission schedules to make full use of transmission channels and improve operational flexibility. Meanwhile, receiving power grids should coordinate the operations between southwestern hydropower and their local plants, and hydropower allocation among subordinate power grids. The differences in operation characteristics, regulation ability, and load demands will be helpful for efficiently absorbing large-scale outer hydropower. Reasonable economic incentives and compensation mechanisms are considered as another method to alleviate hydropower curtailment. Ancillary service market and discrepant electricity prices during different receivers and different periods are suggested. The overall analysis results indicate that there is great space for promoting hydropower absorption under existing transmission channel conditions.