Consumption of alternative transportation fuels held steady in 2009, with a total of 431,107 thousand gasoline-equivalent gallons, compared to 430,329 thousand gasoline-equivalent gallons in 2008. The natural gas share accounted for about 52% of all alternative fuels consumed by alternative transportation fuel vehicles (AFVs). Propane and E85 accounted for 30% and 16% respectively, while electricity, hydrogen, and other fuels accounted for the remaining 2%.
While the consumption of natural gas over the past five years in AFVs has increased due to its predominant use in the transit bus industry, consumption of propane has decreased from 45% of the overall alternative fuel consumption in 2008 to 30% in 2009. The consumption of propane in heavy duty vehicles has remained relatively constant over the past five years; however, consumption of propane in light duty and medium duty vehicles has dropped significantly due to fleet retirements in these categories. Many fleets have replaced their light duty vehicles with flexible fueled and gasoline hybrid vehicles.