With fuel prices at their highest since 2014, compressed natural gas as an alternative fuel for fleet operations is once again getting attention as a cheap, super-clean alternative to diesel or gasoline. The truth is, many fleets that switched to CNG a number of years ago have been quietly going about their business and never looked back.

Sheehy Mail Contractors, out of Waterloo, Wisconsin, is one such fleet. Founded in 1952, Sheehy operates a fleet of straight trucks and tractors. About 70% of its operations are focused on U.S. Postal Service contracts and the remainder on hauling freight. And it’s a company with a culture of fuel economy deeply embedded in its DNA.

“Our founder, Gerald Sheehy, was putting homemade components on his trucks from the very beginning in an effort to boost fuel economy,” says Nick Myers, communications and brand strategist for the carrier. Around seven years ago, executives at the carrier decided the time was right to seriously look at CNG as an alternative fuel.

Today, less than a decade into its “look” at CNG, it powers 90% of Sheehy’s trucks. “We’ve still got a few diesel trucks in the mix,” Myers says. “But we’ve slowly, but surely, been acquiring CNG-powered units since it became clear the fuel would work well in our applications.”

Even though the spotlight fell away from CNG after diesel prices stabilized and returned to more “normal” levels a few years ago, CNG technology and infrastructure kept right on evolving and expanding, Myers says, which has made Sheehy’s steady conversion to the new fuel surprisingly painless.

“The national CNG network is extremely stable today,” he says. “This means that we enjoy stable fuel prices as well. They don’t fluctuate much, if at all, and are holding steady around $1.99 a gallon — and we won’t have to deal with the usual Memorial Day price increases other fleets will as refineries switch over from winter- to summer-blended fuel formulations. Even better, over the past decade, we’ve seen an expansive CNG fueling network build up, which has made it easier for our drivers to find fuel, no matter where they are in our area of operations.”

Driver acceptance and training has been a concern for some fleets considering a switch to CNG. But Myers says Sheehy received very little pushback as it began to move to the new fuel in earnest. In fact, today, he says, Sheehy executives consider CNG a secret weapon in the current driver shortage crisis. “We never had any major resistance from our driver force,” he says. “In fact, many of our drivers — most of whom have been with us 20 years or more — prefer CNG over diesel.”

That’s because the trucks are much cleaner to fuel, with no spills, mess or odors, and tend to ride better, he says. “We’ve tweaked our automated manual transmissions to deliver more low-end torque. The trucks still don’t have as much get-up-and-go as diesel-powered units, but our drivers have gotten used to that. New drivers are still a bit hesitant when they first get behind the wheel of a CNG truck. But usually it becomes a non-issue for them as well very quickly.”

CEO John Sheehy notes that while operating costs are “about neutral” compared to diesel, the fleet enjoys a return on investment from CNG that is simply out of reach for fleets running conventional fuels. “We mainly measure our CNG ROI in terms of being good stewards of the environment and the preferential treatment we receive from our customers,” he says.

Myers echoes this sentiment. “Sheehy saves a lot of money on fuel,” he says. “We also routinely win awards for being a green fleet and protecting the environment, receive tremendous good will from our customers and the communities we serve. And we have happier drivers with less turnover. So for us, CNG has been a win on multiple fronts.”

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