Energy and Exergy Performance of Hydrogen Turbine Coupled with Partial Heating Supercritical Carbon Dioxide Cycle

The development of hydrogen turbines combine cycle is crucial for advancing the hydrogen economy. However, the performance of the combined cycle is significantly influenced by the selection of an optimal bottoming cycle. Among various options, the supercritical carbon dioxide (sCO₂) cycle has emerged as a promising candidate due to its superior thermal efficiency compared to traditional steam cycles. This study investigates the performance of hydrogen gas turbines integrated with an sCO₂ bottoming cycle. The Kawasaki M1A-17 turbine was selected as the gas turbine and the turbine model was corroborated by comparing the results with the KAWASAKI catalogue. The partial heating cycle layout of the sCO₂ was selected as the bottoming cycle, since the partial heating cycle has been shown to outperform other configuration in terms of waste heat recovery. The analysis employed energy and exergy perspective to provide a comprehensive assessment of each configuration. The exergy analysis revealed the optimum turbine inlet temperature is 400°C for the inlet pressure of 210 bar. At 400°C and a compressor inlet temperature of 35°C, the sCO2 cycle produces net power of 834.31 kW. At these conditions, the H2 turbine only efficiency is 28.8% while the combine cycle offers an efficiency of 41.01%. The sCO2 cycle performance improves considerably at cooler temperatures. For a compressor inlet temperature of 15°C, the sCO2 can produce net power of 931 kW and the 1.5%-pt improvement in the combined cycle efficiency can be observed.