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The cost of hydrogen delivery for transportation accounts for most of the current H 2 selling price; delivery also requires substantial amounts of energy. We developed harmonized techno-economic and life-cycle emissions models of current and future H 2 production and delivery pathways. Our techno-economic analysis of dispensed H 2 costs guided our selection of pathways for the life-cycle analysis. In this paper, we present the results of market expansion scenarios using existing capabilities (for example, those that use H 2 from steam methane reforming, chlor-alkali, and natural gas liquid cracker plants), as well as results for future electrolysis plants that use nuclear, solar, and hydroelectric power. Reductions in greenhouse gas emissions for fuel cell electric vehicles compared to conventional gasoline pathways vary from 40% reduction for fossil-derived H 2 to 20-fold for clean H 2. Supplemental tables with greenhouse gas emissions data for each step in the H 2 pathways enable readers to evaluate additional scenarios. [Display omitted] • Hydrogen packaging, transmission, and distribution (delivery) were examined. • Techno-economic and life-cycle emissions models of H 2 delivery were harmonized. • Fuel cell electric vehicle market expansion scenario selections were guided by cost. • Life-cycle GHG emissions were compared with light-duty gasoline vehicle pathways. • GHG emissions reductions for selected pathways ranged from 40% to 20-fold. [ABSTRACT FROM AUTHOR]

Because of increasing environmental and energy security concerns, a detailed understanding of energy efficiency and greenhouse gas (GHG) emissions in the petroleum refining industry is critical for fair and equitable energy and environmental policies. To date, this has proved challenging due in part to the complex nature and variability within refineries. In an effort to simplify energy and emissions refinery analysis, we delineated LP modeling results from 60 large refineries from the US and EU into broad categories based on crude density (API gravity) and heavy product (HP) yields. Product-specific efficiencies and process fuel shares derived from this study were incorporated in Argonne National Laboratory’s GREET life-cycle model, along with regional upstream GHG intensities of crude, natural gas and electricity specific to the US and EU regions. The modeling results suggest that refineries that process relatively heavier crude inputs and have lower yields of HPs generally have lower energy efficiencies and higher GHG emissions than refineries that run lighter crudes with lower yields of HPs. The former types of refineries tend to utilize energy-intensive units which are significant consumers of utilities (heat and electricity) and hydrogen. Among the three groups of refineries studied, the major difference in the energy intensities is due to the amount of purchased natural gas for utilities and hydrogen, while the sum of refinery feed inputs are generally constant. These results highlight the GHG emissions cost a refiner pays to process deep into the barrel to produce more of the desirable fuels with low carbon to hydrogen ratio. [ABSTRACT FROM AUTHOR]