Intermodule Management within a Large-Capacity High-Temperature Power-to-Hydrogen Plant

High-temperature power-to-hydrogen based on solid oxide electrolysis cells (SOECs) is a promising energy storage technology. A large-capacity plant can be assembled from multiple SOEC modules by utilizing the inherent modularity and scalability of cell stacks. Despite the sufficient research on a single SOEC module, the intermodule coordination to optimize their performance as a group is rarely studied in the literature. Starting from common characteristics of SOEC, this paper proposes a management strategy based on the production-curve model of each module to exert the additional flexibility provided by a modular configuration. Specifically, the strategy optimizes the load allocation, including the switching arrangements among modules, while meeting the load commands and reserve requirements, as shown in Fig. 2 . The optimization can be linearized into a mixed integer linear programming formulation for efficient problem solving. The strategy is proven effective in lowering operating costs in a numerical case. Moreover, the results suggest some valuable patterns, such as the shutdown preferences of less efficient and large-capacity modules and the equimarginal principle for running modules.