Fuel Life-Cycle Analysis of Hydrogen vs. Conventional Transportation Fuels

Abstract

Fuel life-cycle analyses were performed to compare the affects of hydrogen on annual U.S. light-duty transportation emissions in future year 2030. Five scenarios were developed assuming a significant percentage of hydrogen fuel cell vehicles to compare different feedstock fuels and technologies to produce hydrogen. The five hydrogen scenarios are: Central Natural Gas, Central Coal Gasification, Central Thermochemical Nuclear, Distributed Natural Gas, and Distributed Electrolysis. The Basecase used to compare emissions was the Annual Energy Outlook 2006 Report that estimated vehicle and electricity mix in year 2030. A sixth scenario, High Hybrid, was included to compare vehicle technologies that currently exist to hydrogen fuel cell vehicles that commercially do not exist. All hydrogen scenarios assumed 30% of the U.S. light-duty fleet to be hydrogen fuel cell vehicles in year 2030. Energy, greenhouse emissions, and criteria pollutant emissions including volatile organic compounds, particulate matter, sulfur dioxides, nitrogen dioxides, and carbon monoxide were evaluated. Results show that the production of hydrogen using thermochemical nuclear technology is the most beneficial in terms of energy usage, greenhouse gas emissions, and criteria pollutant emissions. Energy usage decreased by 36%, greenhouse gas emissions decreased by 46% or 9.6 x 108 tons, and criteria emissions were reduced by 28-47%. The centrally-produced hydrogen scenarios proved to be more energy efficient and overall release fewer emissions than the distributed hydrogen production scenarios. The only hydrogen scenario to show an increase in urban pollution is the Distributed Natural Gas scenario with a 60% increase in SOx emissions..