(Image source: U.S. Energy Information Administration, Monthly Energy Review)
In the United States, petroleum is by far the most-consumed transportation fuel. But recently the share of fuels other than petroleum for U.S. transportation has increased to its highest level since 1954, a time when the use of coal-fired steam locomotives was declining and automobile use was growing rapidly.
The recent increase can be mostly attributed to increased blending of biomass-based fuels with traditional vehicle fuels and growing use of natural gas in the transportation sector.