Evaluation of Electrification Incentives Using the MA3T Model 

Abstract
Cities, regional agencies, and States throughout the U.S. are increasingly developing energy and climate action plans to meet greenhouse gas (GHG) reduction and renewable energy objectives. The City of Boston, Massachusetts and stakeholders worked through the Carbon-Free Boston Initiative to chart a path towards carbon neutrality by 2050. As part of this effort, the city was interested in understanding the potential impact of policies and incentives to encourage consumer adoption of light-duty electric vehicles (EVs). The project team applied the Market Acceptance of Advanced Automotive Technologies (MA3T) model developed by Oak Ridge National Laboratory. Implemented in Excel, MA3T is a tool for analyzing scenarios of demand for various automotive powertrain technologies in response to changes in technologies, infrastructure, energy prices, consumer preferences, and policies. The project team first adjusted the MA3T model to reflect local population characteristics and energy prices. The project team then tested different policies in the model relating to vehicle technology costs, consumer financial and non-financial incentives, and home, workplace, and public charging availability. The baseline forecast shows an EV sales market share of about 25 percent in 2030 increasing to 50 percent in 2050. This is on the low end of industry forecasts, which may be reasonable given the difficulty in accessing charging in an environment with large numbers of multi-family residential buildings (only 40 percent of Boston metropolitan area residents have access to a private garage). Eliminating constraints on public charging availability had only a modest impact on market penetration, but providing universal home and workplace charging availability had a substantial impact, increasing sales shares to over 75 percent by 2035. Financial incentives (for vehicles or infrastructure) and vehicle cost reductions also had large impacts, scaling to the size of the incentive or cost reduction; although sunsetting incentives blunted the long-term impacts. The ratio of battery EVs to plug-in hybrid EVs was also explored under different scenarios. EV market penetration as measured based on vehicle population or vehicle miles of travel (VMT) lags sales by a five to 10 years; in the maximum charging availability scenario, sales reached 50 percent by 2032 but the electric VMT fraction did not reach 50 percent until 2040, increasing to 75 percent by 2050. This suggests that early and aggressive action is needed to achieve long-term GHG reduction goals.