Power-to-methane based on the solid oxide electrolysis cell is considered as a promising technology for energy storage. Most research employed the lumped parameter method to establish the core componentsâ€™ model (i.e., solid oxide electrolysis cell and/or methanation reactor) for the performance analysis of the overall power-to-methane system, which is unable to reveal the performance of the core components accurately. Thereby the safety and stability of the overall system cannot be evaluated reasonably. In this paper, the distributed parameter method for the model of the core components is conducted to evaluate the performance of the overall system reasonably with the consideration of the temperature gradient of the solid oxide electrolysis cell as well as the maximum temperature of the methanation reactor. The results indicate that the temperature gradient of the solid oxide electrolysis cell should be kept as low as possible with the increasing overall efficiency and methane yield, and it is necessary to control the operating temperature of the methanation reactor in a rational range to avoid the non-ignition and catalyst deactivation.
Keywords energy storage, power-to-methane, solid oxide electrolysis cell, methanation reactor, distributed parameter method, performance assessment