• Emission
• Hydrogen
• Leakage
• Pipeline
• Turbomachinery.
• Value Chain

Due to the need to decarbonize future energy production, new energy technologies and fuels have been developed to reduce the carbon footprint. Hydrogen is seen as a possible fuel of the future and its use is expected to grow sharply; moreover, it is seen as an energy vector and its value chain is growing and is going to have an impact on energy use and hard-to-abate sectors. Recent studies have classified hydrogen as an indirect greenhouse gas with a significant impact on climate and atmospheric composition. Therefore, it is important to identify and prevent hydrogen leakage.
The aim of this work is to provide a critical analysis of all the emission sources and a preliminary inventory of hydrogen leakages across the entire value chain. After a brief introduction to the hydrogen value chain, the results of literature works conducted to classify the environmental impact of hydrogen are presented and critically analyzed. Moreover, the entire hydrogen value chain has been studied and data has been collected from various literature sources to predict the emissions to be expected from a future hydrogen economy. A focus is provided on hydrogen leakage from pipelines, and some solutions to reduce or eliminate emissions are presented. Finally, hydrogen leakage recovery systems from turbomachinery are discussed.