Performance analysis of waste heat recovery in hydrogen storage process based on TEG

A large amount of waste heat is generated when hydrogen is compressed. This study combines hydrogen compression hydrogen storage with thermoelectric power generation and uses thermoelectric power generation to convert the waste heat in the hydrogen storage process into usable electrical energy. By establishing a mathematical model, the combination of hydrogen compression and storage with a thermoelectric power generation model was studied, and the heat generated during the compression of hydrogen was recovered and utilized by thermoelectric generation. The effects of hydrogen temperature and mass flow rate at hot side on the performance of the thermoelectric power generation device is studied. The results showed that two operating parameters, hydrogen inlet temperature and hydrogen mass flow rate, had a significant impact on the maximum output power, conversion efficiency, and energy recovery rate. Specifically, with the increase of hydrogen mass flow rate, the maximum output power and optimal component length increased significantly. When the hydrogen mass flow rate is fixed, the higher the hydrogen inlet temperature and the lower the cold-side inlet temperature, the higher the output power, and the optimal module length did not change. This indicates that for a fixed length thermoelectric power generation device, there exists an optimal hydrogen mass flow rate value that can achieve the highest energy recovery rate. When L=1m, the energy recovery rate reaches the maximum value at a mass flow rate of 20g/s.