Integration of hydrogen compressors and turbines into current and future hydrogen infrastructure

Fuel cell-based systems are emerging as the future focus for global adaptation, and hydrogen compressors and turbines, as economically critical versions, are at the technological edge of product development of hydrogen-based energy systems in sustainable energy initiatives. As a novelty, the paper deals with the issues behind implementing hydrogen machinery technologies to bring about a resilient hydrogen infrastructure, also powered by fuel cells, and it aims at strengthening the argument for evolving policies and comprehensive approaches that can cope with the technical, infrastructural, and market-related hurdles. More specifically, the present paper analyzes several hydrogen compressor technologies with their unique advantages and disadvantages. Among them, centrifugal compressors are seen to become their most efficient on the large-scale manufacture of hydrogen and allow compression ratios up to 30:1 with isentropic efficiencies between 70 and 90 %. On the other hand, electrochemical hydrogen compressors exhibit operation with no vibration, reduced noise, and level of hydrogen purification, among others, and offer a plus in a module, with lower energy consumption, up to half value compared to mechanical compressors. Meanwhile, hydrogen turbines are evolving to accommodate hydrogen mixes, with the current technological activity in the turbine sector allowing for a blend of 30 % hydrogen and 70 % methane. In comparison, prototypes have been already tested using 100 % hydrogen. Within this context, this paper describes ongoing work related to efficiency improvements and cost reduction of hydrogen machinery.