The Carbon Content of Hydrogen Vehicle Fuel Produced by Hydrogen Electrolysis

Abstract

This paper discusses the four points in the Kreith and Isler August, 2002 Journal of Solar Energy Engineering Discussion Note, “Comments Dealing with Fuel Cell Energy Policy and Renewable Energy”. The paper compares the carbon emissions (gm-CO2 /mi) of the current US passenger gasoline vehicle (GV) fleet with a proposed US passenger hydrogen vehicle (HV) fleet. The paper uses the efficiency method to compute the carbon content (gm-CO2 /gal-H2 ) of hydrogen vehicle fuel (HVF) produced by a hydrogen electrolyzer (HE). The carbon content of the electricity (gm-CO2 /kWh) used to power a HE is used to compute the carbon content of the HVF. The fuel efficiency (mpg) of the current US GV fleet and of the proposed HV fleet are used to compute the carbon emissions of the two fleets. The four points of Kreith and Isler are demonstrated for H2 from a HE. Equations and a list of abbreviations are provided.