Exploratory Dynamic Models of Alternative Fuel Vehicle Adoption
Identifying socioeconomic characteristics and vehicle characteristics, including a market share of a specific vehicle, influencing on a choice of a vehicle is important for forecasting demands for alternative fuel vehicles (AFVs). Over the time, how changes in these characteristics will affect on the demands is also important. And by connecting with supply, how changes in demands for AFVs will make an effect on the supplies becomes important. This paper forecasts market shares of AFVs in demands and supplies.
First, in a demand part, a dataset of National Household Travel Survey in 2009 is used to identify factors which influence on a choice of AFVs by logit models. And then by using coefficients from the logit models, a dynamic normative model is proposed to forecast demands for Toyota Prius, a sort of hybrid vehicles, with respect to changes in characteristics such as a gas price and a vehicle price. Because a dynamic normative model is a simulation model with unknown values of parameters, these values are randomly defined to track the changes in market shares of Prius based on an annual vehicle market share data.
Next, in a supply part, proportions of hydrogen fuel cell vehicles (HFCVs) with respect to the density of hydrogen refueling stations are estimated by logit models. And then by using these results, a competition model is proposed to forecast supplies for HFCVs. Forecasting supplies for HFCVs is based on demands which is forecasted from a dynamic normative model.
Last, it is found that supplies of HFCVs from the competition model exceed affordable numbers of themselves for the market, because the demands for HFCVs from a dynamic normative model don't consider affordable numbers of HFCVs for the market. Therefore, to connect results from two models, feedback methods are used.
The results indicate that the market share of AFVs will exceed that of ICEs when: 1) a gasoline price is increased, 2) a vehicle price of AFVs is decreased, 3) the initial market share of AFVs is large, and 4) the density of refueling stations is increased.