Natural gas as a bridge to hydrogen transportation fuel: Insights from the literature

Our review suggests it is not attractive to re-purpose or overbuild NG fueling station equipment for future hydrogen service. Transporting H2/NG blends in the NG pipeline grid appears technically possible at modest fractions of 5-15% hydrogen by volume, but requires careful case by case assessment and could be expensive. Blending does not enable major reductions in GHG emissions from transport, unless “green” hydrogen can be cost effectively separated from the blend and delivered to highly efficient fuel cell vehicles. Ultimately, blend limits could make it difficult to utilize the existing NG system to deliver hydrogen at the scale needed to achieve deep cuts in transportation related GHGs. A dedicated renewable hydrogen system would be needed, if zero emission fuel cell vehicles play a major role in a future low carbon world.