Low-carbon economic optimization of park integrated energy system under hybrid market regulation: A multi-scenario dispatch system integrating ladder-type carbon trading and green certificate trading

With the aggravation of the global greenhouse effect and the worsening of the energy crisis, renewable energy efficient utilization and low-carbon transition have become the core issues in the energy sector. Meanwhile, the multiple market regulations have increasingly emphasized the low-carbon requirements for energy development. However, the combined heat and power (CHP) units of the Park Integrated Energy System (PIES) have traditional-model limitations, which challenge the efficient consumption of renewable energy. In this regard, this research designs an optimal dispatch model based on an interaction trading mechanism of Ladder-type Carbon Trading (LCT)-Green Certificate Trading (GCT) with CCP coupling, which couples CHP, Carbon Capture and Storage (CCS) and Power-to-Gas (P2G). First, an analysis is conducted on the operation principles of LCT and GCT, followed by the development of their models and the interaction mechanism. Second, the CCP coupling model is established with subsequent investigation revealing the coupling characteristics of electricity and heat within the CCP mode. Finally, the PIES optimal dispatching model is constructed with the optimization objective of minimizing the total cost. The simulation results demonstrate that the proposed dispatching strategy significantly reduces total costs and carbon emissions, and improves renewable energy utilization. It is crucial to set reasonable carbon trading base price, interval length, green certificate price, green certificate quota coefficient and conversion coefficient among LCT-GCT. Under the CCP mode, the LCT-GCT interaction mechanism enables the PIES to achieve dual economic-ecological benefits, providing a novel and synergistic pathway for collaborative integration between traditional CHP and renewable energy projects.