Leveraging Electrochemical CO2 Reduction for optimizing comprehensive benefits of multi-energy systems: A collaborative optimization approach driven by energy-carbon integrated pricing

The Multi-Energy System (MES) with multiple energy services and emission reduction has significant potential to facilitate the low-carbon transformation of the energy sector. This paper proposes a novel MES framework that integrates Electrochemical CO2 Reduction (ECO2R) to effectively handle excess Renewable Energy (RE) and internal carbon emissions. The integration of the ECO2R link enables the MES to engage in carbon emission trading and generate revenue from chemical product sales. Considering the critical role of market mechanisms in system operation optimizations, a collaborative optimization model is developed, driven by a gas-electricity-carbon integrated pricing strategy. Using a Nash equilibrium game approach, the model allows electricity, gas, and heat subsystem operators to pursue their own benefits in limited communication. Case studies validate the effectiveness of the proposed optimization model. The simulation results show that compared to the traditional MES, the ECO2R-MES can timely consume surplus RE, reduce CO2 emissions by 2,706.73 kg, and generate revenue of 11,481.9 CNY in the electrochemical process. Furthermore, this study examines the impact of various chemical outputs and carbon market factors on system performance and profitability.