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The transition to a hydrogen economy will require an intermediate energy carrier until a sufficient hydrogen infrastructure can be implemented. A likely near-term candidate is the on-board or on-site production of hydrogen from steam-methanol reforming. The low tolerance of PEM fuel cell anode electrocatalyst, to the carbon monoxide produced during reforming, necessitates a hydrogen purification or carbon monoxide clean-up sub-system. Considerable advantages can be gained from the use of a steam-methanol reformer with a palladium-silver alloy membrane, hydrogen purification unit. In the present work we have examined such a system. A simulation comprised of a Polymer Electrolyte Membrane Fuel Cell electrochemical model, a membrane permeation model and a commercially available thermodynamics calculation package was constructed. The case investigated in this work is of a 25 kW nominal DC power generating system. A maximum efficiency of 40% was achieved at reformer and membrane unit conditions of 200°C and 300 psia with 97% conversion of the inlet methanol. The effects of variation in temperature and pressure where also investigated. It was found that the reformer and membrane unit pressure had the most significant effect on overall system efficiency. The system efficiency increases with pressure reaching a maximum at the upper limit of the operating region, 300 psia.

Existing research on resource booms and their impacts has largely focused at the national level and been undertaken from an economic perspective, primarily through the lens of the resource curse. This study investigates an emergent resource boom in Ghana, where oil was discovered in 2007. Given the considerable existing research on national-level impacts of resource extraction, this study looks at the urban impacts of oil exploitation on the city of Sekondi-Takoradi, the largest urban settlement closest to the nation's offshore oil fields. Drawing on detailed questionnaires completed by 636 people across multiple neighbourhoods, the study examines how oil discovery and exploitation have impacted the city. The study finds that many of the changes facing Sekondi-Takoradi can be understood in light of gentrification theory. This is important because there has been considerable debate over the extent to which models of gentrification, largely forged in the developed world, are relevant in the developing world. The findings of this study extend existing knowledge by not only connecting resource booms to processes of urban gentrification in Sub-Saharan Africa but by also demonstrating that multiple forms of gentrification take place simultaneously in these conditions. The paper concludes by suggesting several avenues through which planners and policymakers might better prepare for the kinds of urban changes that are likely to result from developing world resource booms.

In the face of rapid global urbanization, cities are increasingly at risk from major disasters. While considerable attention has been given to other aspects of urban post‐disaster recovery, less has been dedicated to rubble clearance. This article examines the dynamics of rubble clearance through a study of how the diverse organizations responding to the 2010 Haiti earthquake addressed this issue in Port‐au‐Prince. It draws on interviews with 52 organizations spanning the range of organizational types engaged in recovery efforts. Building on an evaluation of rubble clearance plans developed for other seismically at‐risk cities, the results indicate that organizations in Port‐au‐Prince lacked a shared understanding of who should coordinate, and engage in, this vital activity. The diverse organizations involved in recovery brought widely diverging norms concerning rubble clearance to a context with weak plans in place for this task. The outcome was uncoordinated action and slow progress. The article draws on the literature on interorganizational norms to contextualize its findings from Port‐au‐Prince. It concludes by arguing for efforts to generate new, shared norms concerning who should lead urban rubble clearance and, in particular, for greater support for, and deference to, local plans around this issue. Such plans would enable governments to establish robust protocols to coordinate action on this increasingly important challenge for cities.