Sheehy Mail Contractors, one of HDT's Top 50 Green Fleets for 2017, announced that it is testing the Cummins-Westport ISL G Near Zero natural gas engine using renewable natural gas, which the company said will produce the lowest carbon footprint of any modern-day fuel.

Since June 2017, SMCI has been testing the ISL G Near Zero (NZ) NOx natural gas engine in two of its trucks. These trucks have been traveling to the East Coast daily while producing near zero emissions.

The engine has been designed from the ground up to use natural gas in several forms, including compressed natural gas, liquefied natural gas, or renewable natural gas. The emissions are so miniscule that SMCI believes that by combining RNG fuel with the ISL G Near Zero engine, trucks can run cleaner on RNG fuel than on electricity.

Although electric motors don’t burn fuel, most of the electricity produced in the U.S is done so by consuming various fossil fuels, such as coal. RNG fuel, however, can be produced naturally via biomethane from landfills, animal fodder, and even wastewater treatment facilities.

“The mode of power will be the mode that has the lowest cost of operation including acquisition costs and has the most robust refueling/recharging system”, said John Sheehy, CEO of Sheehy Enterprises.

Sheehy Mail Contractors is a transportation company based in Waterloo, Wis. Since 1952, Sheehy Mail has been a premier mail contractor for the U.S Postal Service.