Increasing trends of global hydrogen demand necessitate practical information for the upcoming hydrogen projects. This review aims to update knowledge about hydrogen supply chains by providing practical information about its economic and environmental sustainability, focusing on announced hydrogen projects. Trade-offs were found between production costs and environmental benefits, with the hydrogen produced by renewable-powered electrolysis presenting higher costs between 3–10/kg H 2 compared to 0. 7–2. 3 kg H 2 from natural gas-produced hydrogen. However, renewable hydrogen had significantly lower life cycle emissions, between 0. 2 and 3. 5 kg CO 2 eq/kg H 2 compared with 6. 5–14. 5 kg CO 2 eq/kg H 2 from natural gas produced hydrogen, indicating the origin of hydrogen is key to better sustainability. Hydrogen production by electrolysis and its distribution via pipelines were the most popular pathways among the hydrogen projects. A range of hydrogen energy carriers for transportation of hydrogen at varying distances and modes of transportation were further reviewed and compared to transportation of compressed and liquified hydrogen. Distribution of compressed and liquefied hydrogen by pipelines and trucks presented slightly lower emissions for 100 km transport, although the transport pathways were less economic than transport using liquid organic hydrogen carriers (LOHC) and ammonia. The transport of liquid hydrogen and ammonia by ships had lower cost per kg of delivered hydrogen for 5000 km transport, whereas the same distance transport via pipelines had significantly higher cost due to capital cost and cost for hydrogen compression. The pipeline distribution, especially using repurposed pipelines, can be more economical for large-scale and long-distance transmission, however, energy consumption for hydrogen recompression can incur additional costs and emissions. Energy consumption for hydrogen compression, liquefaction and reconversion had a significant contribution to the total emissions with potential emissions reduction by using renewable energy and renewable hydrogen carriers. Although there are emission standards for ensuring sustainability of hydrogen supply chain, lack of targeted policies and technological standards for promoting renewable hydrogen are some of the challenges. • Renewable hydrogen production presents higher cost than fossil hydrogen. • Renewable hydrogen production has lower greenhouse gas emissions than fossil hydrogen. • Pipelines have lower emissions than trucks for short distance transport of hydrogen. • Transport of liquid hydrogen and ammonia by ships has lower cost than pipelines. • Repurposed pipelines can be economical for large-scale distribution of hydrogen.
Cho et al. (Thu,) studied this question.