Energy Development Research Institute of China Southern Power Grid, Guangzhou 510663, China

With the comprehensive deepening of China's power system reform and the roll-out of the spot market construction, insufficiency of power capacity, massive stranding cost of power resources or other problems have been exposed in several regions. There is an urgent need to improve the capacity market mechanism and the electricity market system to promote unit investment and ensure the sufficiency of power generation capacity. This paper proposes a capacity market mechanism adapting to the clean energy development and spot market operation. On the one hand, the proposed mechanism takes the elements of spot electric energy trading into account, which mobilizes the competitiveness of capacity resources in terms of constant costs and operation costs, strengthens the connection between capacity investment/construction and system operation. This is conducive to the formation of a more practical capacity investment and construction plan. On the other hand, to meet the goal of "carbon peak and carbon neutral", the embedded energy structure constraints are considered to be compatible with industrial structure adjustments so as to obtain the most economical capacity combination that meets the requirements of low-carbon transition for the clean energy. Finally, a bi-level optimal model is established to realize the centralized clearing of capacity bidding considering the spot market operation. The simulation calculations of the modified IEEE 24-bus and other systems show that the proposed mechanism can not only encourage market players' active participation and adaptation to the replacement effect of clean energy costs in the future, but also realize the effective improvement of the overall economic efficiency of the market.