Impact of FreedomCAR Goals on Well-to-Wheel Analysis

Abstract

Because of their high efficiency and low emissions, fuel-cell vehicles are undergoing extensive research and development. When considering the introduction of advanced vehicles, engineers must perform a well-to-wheel (WTW) evaluation to determine the potential impact of a technology on carbon dioxide and Greenhouse Gas (GHG) emissions and to establish a basis that can be used to compare other propulsion technology and fuel choices. Several modeling tools developed by Argonne National Laboratory (ANL) were used to evaluate the overall environmental and fuel-saving impacts associated with an advanced powertrain configuration. The Powertrain System Analysis Toolkit (PSAT) transient vehicle simulation software was used for pump-to-wheel (PTW) analysis, and GREET (Greenhouse gases, Regulated Emissions and Energy use in Transportation) was used for well-to-pump (WTP) analysis. This paper assesses the impact of FreedomCAR vehicle goals on a WTW energy basis. We will demonstrate that, on the basis of near-term (2010) advanced propulsion technologies, fuel cell hybrid vehicles achieve higher fuel economy than their Internal Combustion Engine (ICE) counterparts. However, when the North American natural gas hydrogen pathway is used to produce hydrogen (the most likely lowest-cost source of hydrogen in the near term), diesel hybrids perform the best. To gain the full benefits of hydrogen technology, a more efficient pathway to produce hydrogen, such as renewable energy, should be considered.