Energy and Emissions Implications of Automated Vehicles in the U.S. Energy System

Vehicle automation has the potential to drastically transform the transportation system, which would in turn have energy and environmental implications. There is considerable uncertainty regarding the effect of automation on travel demand and efficiency, regarding the direction, magnitude and interaction of both. We utilize the MARKAL model to examine four previously published scenarios of vehicle automation that consider different effects on vehicle efficiency and travel demands and use the model to provide additional insights on fuel switching, upstream impacts, and air emissions. Model results suggest that an increase in travel demands from automation may lead to greater fuel use and higher fuel prices, potentially increasing the market penetration of alternative-fuel vehicles. In contrast, dramatic efficiency improvements from automation could drive fuel prices lower, greatly reducing the competitiveness of alternative-fueled vehicles. Furthermore, vehicle technology shifts such as these could yield either positive or negative environmental impacts since vehicle technologies can have very different emission signatures. Some automation scenarios even resulted in counterintuitive results. For example, by driving out alternative-fuel vehicles, such as battery electric and hybrids, high levels of efficiency improvement led to a net worsening of air quality. We also found system dynamics to be very important. For example, reductions in liquid fuel prices were shown to drive an uptake in their use. The resulting increase in air pollutant emissions offset a portion of the air quality benefits of automation.