When exploring alternatives to gasoline and diesel, carriers have to consider the benefits of fuel economy versus the cost of onboard energy storage and fuel density, according to a new report by the U.S. Energy Information Administration.
Fuels that require extra storage or are heavy can cut into freight capacity.
Gas accounted for 99 percent of light-duty vehicle fuel use in 2012 because of the energy density and ease of onboard storage. Diesel fuels accounted for more than half of the remaining 1 percent.
“The widespread use of these fuels is largely explained by their energy density and ease of onboard storage, as no other fuels provide more energy within a given unit of volume,” according to the report.
As for alternatives, compressed propane, ethanol, methanol and battery
types are all heavier than diesel fuel and require more storage space.
Compressed hydrogen gas, cooled liquid hydrogen and compressed natural
gas are all lighter alternatives than diesel, but they also require more
storage space. These new fuel types have traditional means beat in terms of economy, however. Hydrogen-powered fuel cells found in electric vehicles double the fuel economy of gas-powered vehicles; battery-powered cells quadruple fuel economy.
“But the costs of fuel cells, hydrogen storage and batteries are prohibitively expensive to most consumers, and the availability of refueling and charging facilities is extremely limited," the report found.
FedEx and UPS both have a growing natural-gas presence in their fleets. According to UPS, its green fleet of vehicles will hit 400 million miles traveled by 2017. FedEx has 58 natural gas vehicles operating in Europe, the Asia-Pacific and Latin America. The company also has 330 hybrid-electric and 43 all-electric vehicles. - Jon Ross