As gasoline use continues to slip nationwide, demand for the country’s second most popular fuel is headed in the opposite direction.
Gasoline demand has eased over the past several years, spurred both by the recession and increased fuel efficiency. Most forecasts show gasoline demand continuing to steadily track downward over the next couple of decades as new fuel efficiency standards roll out.
But while gasoline use may be falling, demand for diesel continues to grow.
Overall energy use by the country’s transportation sector grew by an average of 1.3 percent per year from 1973 to its peak in 2007. From 2012 to 2040, however, demand is expected to decline 4.5 percent, according to the U.S. Energy Information Administration.
The projections show demand to be far from even.
Light-duty vehicles — most of which consume gasoline — are expected to see fuel demand drop 24 percent by 2040, while diesel-consuming heavy-duty vehicles are likely to increase demand by more than 41 percent.
Fuel efficiency also is increasing for diesel vehicles, but the fuel savings are being offset by rising demand for tractor-trailers, buses, vocational vehicles and heavy-duty pickups and vans.
The increase demand “is a result of increased demand for travel as economic output grows,” the Energy Information Administration wrote.
“In contrast to the projected decline in gasoline use, a strong increase in heavy-duty vehicle miles traveled leads to an increase in consumption of diesel fuel.”