A robust design of heat exchanger network for high temperature electrolysis systems

The solid oxide electrolysis cell (SOEC) has been recognized as a promising technology for producing green hydrogen utilizing renewable energy. However, due to various degradation phenomena, the electrochemical performance of SOEC will deteriorate over time. This degradation leads to varying heat duty and inefficient operation. Based on previously reported durability test data, we simulate and optimize a SOEC system with a robust heat exchanger network to address the degradation issue. Overall, a 45.9% redundancy heat exchanger area is designed into the system, which leads to a levelized cost of hydrogen (LCOH) of 4.23 $/kg H2. The system efficiency is 77.4% initially but drops to 63.2% due to degradation. The vaporizer consumes the most energy in the heat exchanger network.