Modelling study of the thermal management of a RSOC system

The source of energy in the grid is transitioning from fossil fuels towards renewable energy sources. With an increasing amount of electricity provided by offshore wind turbines, the source of the electricity becomes more intermittent. These variations within the source of electricity increases the challenge to match the supply and demand of electricity within the grid. To balance the supply and demand, electricity storage should be applied. One solution is the reversible solid oxide cells (RSOC). Which uses the conversion of hydrogen from electricity and vice versa. RSOC are cells capable of both electrolysis and fuel cell operation. The RSOC is promising solution for hydrogen storage due to their high round-trip efficiency. Some models have been developed for the RSOC. However, models which include the balance-of-plant (BoP) required to operate the RSOC are not considered.

This study aims to develop and compare different concepts for the BoP to improve its performance and economic viability. For the comparison, a dynamic model for the BoP of the RSOC is developed. For this purpose, multiple variations of the BoP are described to be able to operate the RSOC. These include a BoP based on electric heaters and the use of heat recovery to increase the performance of the system. Improving the efficiency by means of thermal energy storage (TES). The use of metal-hydrides as a means of thermal management in combination with the storage of hydrogen. The performance of the different concepts is measured based on the efficiency and the levelized cost of electricity.

The developed model allows to determine the power consumption and required capacity of the different concepts. The model is used to compare different concepts of the BoP of the reversible solid oxide cell. However, for future elaboration of a single concept a more detailed model could be used. For the comparison of the levelized cost of electricity (LCOE) further research and selection of components is required. Due to the range of the cost regarding components it could not be determined which is economically the best suited solution.