Optimal Capacity Configuration of a Low-Carbon Energy System Considering Carbon Capture Technology and Hydrogen-Diversified Utilization Under Multiple Operational Scenarios

Abstract

To enhance the utilization of concentrated solar power (CSP), and reduce the wind abandonment rate of wind power (WP) and the carbon emissions from the traditional coal-fired unit (CFU), this study introduces oxygen-enriched combustion capture technology to retrofit the conventional CFU, and configures CSP with heat recovery unit (HRU) for participation in heating, along with coupling methanation reactor (MR), high-temperature solid oxide electrolysis cell (SOEC), hydrogen-blended gas cogeneration system, and energy storage units to create a low-carbon energy system (LCES) that includes electricity-heat-gas integration and hydrogen diversified utilization. The system's optimal capacity configuration methodology is also established. Firstly, considering the uncertainties of WP and direct normal irradiance (DNI), as well as their temporal correlations with electrical load (EL), a multi-operational scenarios extraction model is established based on a multi-stage data processing algorithm. Secondly, building upon the probability-based multi-operational scenarios, the conditional value at risk (CVaR) theory is employed to quantify the risks arising from uncertainties. With the objective of minimizing total cost, an LCES optimal capacity configuration model is formulated. Finally, through case study validation, the results indicate that the system, under the scenario of meeting the load demand, can reduce annual carbon emissions to 249,573.31 t, decrease the wind abandonment rate to 1.32%, enhance the CSP utilization rate to over 84%, and provide the basis of quantification for decision-makers with varying risk preferences when addressing capacity configuration issues.INDEX TERMS Multi-operational scenarios, oxygen-enriched combustion capture technology, low-carbon energy system (LCES), conditional value at risk (CVaR), capacity configuration. NOMENCLATUREA. ABBREVIATIONS CSP Concentrated solar power. WP Wind power. CFU Coal-fired unit. HRU Heat recovery unit. MR Methanation reactor. SOEC Solid oxide electrolysis cell. LCES Low-carbon energy system. DNI Direct normal irradiance. EL Electric load. CVaR Conditional value at risk. PCC Post-combustion capture. ASU Air separation unit. CPU Compression purification unit. CSP-HRU Concentrated solar power with heat recovery unit. CFPS Coal-fired power system. HST Hydrogen storage tank. HBGT Hydrogen-blended gas turbine. HBGB Hydrogen-blended gas boiler. HL Heat load.