Project SULPHURREAL Development of digital twin of thermochemical cycle for solid sulfur production for long-term storage of solar energy

Abstract

To advance the sustainable production of solar electricity, the SULPHURREAL project is developing an innovative thermochemical cycle that stores solar thermal energy in solid sulphur, enabling the generation of renewable and dispatchable power. Key processes, including sulphuric acid splitting, sulphur dioxide disproportionation and sulphur combustion, will be demonstrated at lab scale and integrated into an industrialscale system design. To enable the computational modelling of the whole process, overcoming limitations of traditional chemical engineering tools, a hybrid digital twin is being developed to model and optimize the cycle, combining physics-based and machine learning approaches. Initial results show highly accurate and computationally efficient simulations of a main section of the process, covering the use of solar heat to split sulphuric acid into sulphuric dioxide. Future work will expand the digital twin framework to the full cycle, supporting flexible and real-time system optimization, with potential for integrating future process data.