Zijian Meng’s research while affiliated with North China Electric Power University and other places

As China accelerates its transition to a low-carbon society, its power system is facing growing challenges in terms of maintaining adequacy amid a rapidly evolving energy structure. The concept of adequacy, traditionally focused on power capacity and generation, has broadened to include dimensions like flexibility and inertia. Against this backdrop, optimizing the integration of coal power and renewable energy to meet the system’s needs for adequacy, flexibility, and frequency stability has become a critical research area. This paper introduces the concept of “Generalized Adequacy”, expanding the traditional understanding of adequacy, and proposes an optimization model for the coordinated development of coal power and renewable energy based on this concept. This study examines the effects of extreme weather, renewable energy penetration, wind–solar ratios, and generalized adequacy constraints using a case study from a central region of China. The findings reveal that extreme weather conditions drive an increase in photovoltaic installations, while higher renewable energy penetration leads to more wind power installations. Accounting for generalized adequacy constraints can moderate the retirement of coal-fired plants, reducing unnecessary inertia support in normal conditions and ensuring dynamic frequency stability during extreme weather events.

As the Chinese government proposes ambitious plans to promote low-carbon transition, energy storage will play a pivotal role in China’s future power system. However, due to the lack of a mature electricity market environment and corresponding mechanisms, current energy storage in China faces problems such as unclear operational models, insufficient cost recovery mechanisms, and a single investment entity, making it difficult to support the rapid development of the energy storage industry. In contrast, European and American countries have already embarked on certain practices in energy storage operation models. Through exploration of key issues such as investment entities, market participation forms, and cost recovery channels in both front and back markets, a wealth of mature experiences has been accumulated. Therefore, this paper first summarizes the existing practices of energy storage operation models in North America, Europe, and Australia’s electricity markets separately from front and back markets, finding that perfect market mechanisms and reasonable subsidy policies are among the main drivers for promoting the rapid development of energy storage markets. Subsequently, combined with the actual development of China’s electricity market, it explores three key issues affecting the construction of cost-sharing mechanisms for energy storage under market conditions: Market participation forms, investment and operation modes, and cost recovery mechanisms. Finally, in line with the development expectations of China’s future electricity market, suggestions are proposed from four aspects: Market environment construction, electricity price formation mechanism, cost sharing path, and policy subsidy mechanism, to promote the healthy and rapid development of China’s energy storage industry.

Due to the large-scale integration of renewable energy and the rapid growth of peak load demand, it is necessary to comprehensively consider the construction of various resources to increase the acceptance capacity of renewable energy and meet power balance conditions. However, traditional grid planning methods can only plan transmission lines, often resulting in low utilization rates of newly constructed lines. Additionally, static planning methods can only address single-target scenarios and cannot cope with dynamic growth in load and renewable energy. To address these issues, this paper proposes a multi-stage collaborative planning method for transmission networks and energy storage. This method considers the non-line substitution effect of energy storage resources and their characterization methods. It establishes the coupling relationship between resources across different planning stages to achieve coordinated multi-stage planning for transmission networks and energy storage. Based on the IEEE-24 node system and a case study in a northern province of China, the results show that the proposed method reduces investment costs by approximately 30% compared to static planning methods and by about 7.79% compared to conventional grid planning methods. Furthermore, this method can accommodate more renewable energy.