This report assesses zero emissions medium- and heavy-duty vehicle technologies, their associated costs, projected market share, and possible policy mandates and incentives to support their adoption. Cost comparisons indicate that battery-electric transit buses and city delivery trucks are the most economically attractive of the zero-emission vehicles (ZEVs) based on their break-even mileage being a small fraction of the expected total mileage. These ZEVs using fuel cells are also attractive for a hydrogen cost of $5/kg. The most economically unattractive vehicle types for ZEV adoption are long-haul trucks and inter-city buses. Developing mandates for buses and trucks will be more difficult than for passenger cars for several reasons, including the large differences in the size and cost of the vehicles and the ways they are used in commercial, profit-oriented fleets. The best approach will be to develop separate mandates for classes of vehicles that have similar sizes, cost characteristics, use patterns, and ownership/business models. These mandates should be coupled to incentives that vary by vehicle type/class and by year or accumulated sales volume, to account for the effects of expected price reductions with time.

Zero-emission long-haul trucking technologies are being developed that can play a critical role in achieving California’s climate change goals and virtually eliminate air pollution from these vehicles.  Hydrogen fuel-cell electric, catenary electric and dynamic inductive charging technologies are being demonstrated in small scale projects worldwide. In this study, these three zero-emission truck technologies were reviewed in detail and vehicle and infrastructure challenges and costs for each of the technologies assessed. In the near- to mid-term, electrifying the entire California state highway system or deploying large hydrogen stations at many statewide truck stops would require very large capital costs, on the order of billions of dollars, even though, at least initially, there will likely be relatively few zero-emission long-haul trucks in use.  Considering technology readiness, energy efficiency, and capital cost, the most feasible approach for the zero-emission technologies for long-haul trucks may be to deploy local or regional catenary systems. Dynamic inductive charge systems could be introduced, though with perhaps more disruption as roadways are prepared for this service. Hydrogen fuel cell trucks will benefit from some scalability but will require large hydrogen refueling stations along highways. The initial “up-front” investment in infrastructure for hydrogen trucks appears somewhat lower than for the other two options but the cost of providing hydrogen to vehicles will be high, especially if provided using electrolysis.  In the longer-term, all three of the technologies could become economically competitive with diesel trucking, though this depends on many factors and uncertainties.