IntroductionGlobal climate change, air quality concerns, and the geopolitical and economic instability associated with petroleum fuel are driving manufacturers, and society, to find alternatives to gasoline and diesel powered automobiles. Hydrogen powered fuel cell vehicles offer a potential solution to all three major problems because hydrogen can be generated and consumed with little or no carbon footprint, pollutant emissions, or oil usage. The California Hydrogen Highway was the first large-scale governmental foray into the provision of hydrogen infrastructure and provided the needed refueling capacity for early vehicle deployment programs [1]. Thanks in part to the efforts of California and the availability of fueling stations, automakers have made remarkable advances in fuel cell vehicle development and are projecting commercialization in the 2015 timeframe [2]. As this deadline approaches, attention turns to establish a sufficient refueling infrastructure for early consumers. This reality is reinforced by the California Energy Commission's allocation of $22 million for hydrogen station funding for 2010, and another $14 million designated for 2011 [3]. A significant and globally researched part of this potential infrastructure rollout is fueling station placement [4e7]. The initial California Hydrogen Highway plan envisioned wellspaced fueling stations positioned along major transportation corridors [1]. Current planning for initial commercialization focuses on a "cluster" approach whereby several stations are clustered around the geographic fuel cell vehicle deployment regions [8,9]. An early cluster is developing in Orange County, California centered on the existing University of California (UC) Irvine station that will include a Shell Hydrogen station in Newport Beach that is undergoing initial fueling trials as of December 2011, Available online at www.sciencedirect.com journal h om epa ge: www.elsev ier.com/locate/he i n t e r n a t i o n a l j o u r n a l o f h y d r o g e n e n e r g y 3 7 ( 2 0 1 2 ) 1 2 7 3 1 e1 2 7 4 0