Impact of Substituting Hydrogen for Natural Gas on Compressor Station Operation in Gas Networks

Hydrogen is a chemical energy carrier and plays an important role as a storage for renewable energies and the decar-bonization of many energy sectors. The re-utilization of existing gas network infrastructure including its compressor stations is a prerequisite for the development of a hydrogen market. The extent to which compressor stations can be repurposed depends on how the substitution of hydrogen for natural gas changes the operating parameters. To investigate this question, we have developed a model, which we present in this paper. As a case study, we take a compressor station with centrifugal compressor and investigate how the compression power and the power of the cooler at the station outlet change as a function of hydrogen admixture up to the point where hydrogen completely replaces natural gas. The thermal power of the transported gas mixture remains constant. Our results show that the required compressor power is almost quadrupled and the cooling power increases by a factor up to 4.7. Consequently, extensive measures are required to upgrade compressor stations for the compression of hydrogen if a similar thermal power is to be transported in the gas network.