Exploiting the operational flexibility of a concentrated solar power plant with hydrogen production.

• A novel application mode of CSP with HEHP technology is proposed. • The flexible operation benefits of CSP with HEHP technology in the IES are analysed and quantified. • The carbon emission trajectory of the IES containing CSP with an HEHP device is depicted. • CSP with HEHP technology increases the utilization of solar energy. • A rational combination of the hydrogen and thermal energy storage capacities are necessary. The efficient integration of renewable energy with hydrogen storage is an important means for China to achieve carbon neutrality. Concentrated solar power (CSP) is an emerging technology for solar energy utilization that combines the advantages of power generation and energy storage. However, CSP has not been fully exploited because of the high generation cost and an incomplete market mechanism in China. The heat collected by CSP can be utilized for high-temperature electrolytic hydrogen production (HEHP), which is an efficient technology for hydrogen production and storage, and reducing carbon emission. Thus, a low-carbon operating mode for an integrated energy system (IES) consisting of wind, solar and hydrogen energy is proposed in this paper. First, an optimal operation model of electricity-heat-hydrogen coupling for an IES containing CSP and HEHP is established. Second, the effect of CSP with HEHP on the total operation performance of the system is evaluated from the aspects of the system economy, renewable energy utilization, and carbon emission. Finally, the model is validated by a case study of an island IES, and an optimal sizing for hydrogen energy storage and thermal energy storage of CSP is determined. The results show that CSP with HEHP can effectively improve the utilization rate of solar energy and reduce the carbon emissions of the system, offering an approach for carbon reduction planning and the operation of CSP in electric-hydrogen energy systems. [ABSTRACT FROM AUTHOR]