Quantitative assessment of imbalance costs in agency power purchase under the coupled plan and market model

The latest reform phase in the Chinese power market will result in a prolonged period of coexistence between the plan and the market. In this context, the operation of the electricity market gives rise to imbalanced costs because of discrepancies between the planned scale of priority power generation and consumption, inconsistencies in priority power generation and consumption curves, and deviations between forecasts of priority power purchases and actual power consumption. To accurately assess the scale of imbalanced power and the associated costs, this study analyses the formation mechanisms and characteristics of imbalanced costs in a coupled plan and market model, focusing on a power grid that incorporates large-scale foreign power and a complex structure of energy resources. This study presents an assessment model of imbalance costs comprising a typical day-power balance model and a time-period-specific imbalance power calculation model. The evaluation of typical scenarios illustrates that the proposed model can effectively and accurately quantify the scale of the power imbalance and costs within the power grid, thereby providing a robust foundation for power-grid enterprises to develop effective strategies.