UC Davis Institute of Transportation Studies

Public agencies and the trucking industry have recognized the idling of heavy-duty trucks as a significant contributor to fuel consumption and air pollution. Several potential technical solutions are in development, including the utilization of auxiliary power units (APUs). Using fuel cell APUs could be a promising alternative to idling with substantial fuel consumption, emissions, cost, and noise benefits, while serving as a niche for relatively early fuel cell technology market introduction. This paper, using a probabilistic Monte Carlo framework, reports on efforts to characterize existing data on idling trucks, develop an ADVISOR-based vehicle APU model that accurately depicts how utilizing fuel cell APUs to replace heavy-duty truck idling could be implemented, quantify energy consumption reductions, and analyze the economic benefits of the APU. The analysis shows that if fuel cell research targets for APUs are met over the next decade, a market in the tens of thousands of units may be possible in the line-haul trucking industry, and substantial diesel consumption reductions would result.