Natural gas, as compressed natural gas (CNG) and liquefied natural gas (LNG), is the fastest-growing fuel in the transportation sector in the USA, reports the U.S. Energy Information Administration (EIA). The agency projects an average annual growth rate of 11.9 percent from 2011 to 2040.
Heavy Duty vehicles (HDVs) — which include tractor trailers, vocational vehicles, buses, and heavy-duty pickups and vans with a gross vehicle weight rating (GVWR) of 10,001 pounds or more — lead the growth in natural gas demand throughout the projection period. Natural gas fuel consumption by HDVs increases from almost zero in 2011 to more than 1 quadrillion Btu in 2040, at an average annual growth rate of 14.6 percent.
Although HDVs fueled by natural gas have significant incremental costs in comparison with their diesel-powered counterparts, the increase in natural gas consumption for HDVs is spurred by low prices of natural gas compared with diesel fuel, as well as purchases of natural gas vehicles for relatively high-VMT (vehicle miles traveled) applications, such as tractor trailers.
The total number of miles traveled annually by HDVs grows by 82 percent in the Reference case, from 240 billion miles in 2011 to 438 billion miles in 2040, for an average annual increase of 2.1 percent. HDVs, those with a GVWR greater than 26,000 pounds (primarily tractor trailers), account for about three-fourths of truck VMT and 91 percent of natural gas consumption by all HDVs in 2040. The rise in VMT is supported by rising economic output over the projection period and an increase in the number of trucks on the road, from 9.0 million in 2011 to 13.7 million in 2040.