The average 18-wheeler gets less that 7 miles per gallon but that is changing rapidly.  The roughly 1.7 million 18-wheelers in the United States use over 26 billion gallons of diesel fuel annually.  However, Tesla plans to announce a fully electric big diesel engine next month and Cummins introduced a similar motor last month.  The aerodynamics of 18-wheelers is being improved rapidly to improve fuel efficiency.  Truck transmission manufacturers Eaton Corp. and Cummins have joined forces to design lighter-weight more powerful yet more efficient truck engines and transmissions.  Among new fuel-saving aspects of new tractor-trailers are electrified cabs, automatic transmissions, sleeker designs, 360-degree skirts, diesel/electric combo engines, and more.   Environmental sustainability concerns among consumers, governments, producers, and users are spurring 18-wheelers to turn right on green.

Source:  Based on Erica Phillips, “Tractor-Trailers Take Green Turn,” Wall Street Journal, September 23-24, 2017, p. B4.