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NACFE Releases ‘Messy Middle’ White Paper

A new NACFE white paper on trucking's "Messy Middle' transition period away from fossil fuels toward zero-emission vehicles takes a detailed look at the technologies available today.

March 10, 2025
NACFE Executive Director Mike Roeth.

NACFE Executive Director Mike Roeth speaks to journalists at the ATA TMC Annual Meeting in Nashville on March 9.

Photo: Jack Roberts

3 min to read


The North American Council for Freight Efficiency (NACFE) has released a new white paper called Navigating the Messy Middle: The Move to More Sustainable Trucking.

This is the second white paper NACFE has released this year. In February, NACFE introduces a new white paper calling for new definitions for heavy- and long-haul fleet applications. 

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Recognizing that all the powertrain solutions currently available to fleets can make it difficult to determine which solution is best suited to a fleet’s operation, NACFE published a white paper that provides deeper insight into the term Messy Middle.

“I liken the Messy Middle to a smorgasbord where fleets have a wide variety of options,” said Mike Roeth, NACFE’s executive director. “It can seem like an overwhelming number of choices, and we wrote this white paper to bring some clarity to the current situation.”

All Options on the Table

NACFE first began using the term Messy Middle in 2018 to describe the time between now and when trucking gets to a zero-emission future.

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But the paper goes beyond just identifying the various options. Roeth said tt also delves a little deeper into the term Messy Middle. “We have received a good deal of feedback on the idea since introducing it in 2018. Much of it good and some questioning our declaring it a mess. While I don’t think many of us love being in a mess, we don’t always select the situations we find ourselves in,” Roeth said.

“We don’t think messy is necessarily bad,” he added. “In fact, messy can be good because it implies a variety of options available for fleets to choose from.”

In addition, the defining the Messy Middle, the white paper provides a brief overview of the various powertrain options available to fleets today.

NACFE Messy Middle.

Being in a mess means you have options, Roeth said. And that is definitely the case for green trucking today. 

Graphic: NACFE

The key is to choose the right powertrain for the application.

“We maintain a fleet of more than 450,000 vehicles and are always looking at ways to optimize our assets,” said Paul Rosa, senior vice president procurement and fleet, Penske. “We are constantly evaluating powertrain options to determine which make sense for each of our Class 2b to 8 commercial vehicle duty cycles. NACFE’s work on defining the Messy Middle and laying out a framework for evaluating the various options should help fleets have a better understanding of which powertrain solutions will work for them.”

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Decision-Making Framework

The paper also explains the factors that need to be considered when choosing a powertrain solution and provides a framework which is useful in the decision-making process.

“This paper along with the previously published A Need to Redefine Class 8 Long-Haul Trucking, are part of our Run on Less – Messy Middle efforts which also includes a Bootcamp, and will feature profiles of participating fleets and a dashboard of metrics from the fleets’ operations. All of these efforts are designed to help bring clarity to long-haul trucking,” Roeth noted.

NACFE Messy Middle.

NACFE's latest white paper provides deeper insight into the term Messy Middle.

Graphic: NACFE

“To have a ‘middle,’ you have to have a beginning and an end,” Roeth added. 
It’s obvious that the beginning of commercial heavy duty trucks is diesel. And we think it's very probable, if not certain, that the end, or a future state where battery electric and hydrogen fuel cell or zero emission is very likely. Now, 2050, 2040, 2060, who knows when all of that will kind of reach a saturation point? But that's what we mean by the middle. We really believe we're in a middle now. And this middle period is going to scale a bunch of technologies that we don't have today, or we don't have at much scale now. That includes hydrogen ICE, natural gas, renewable natural gas, and on.”

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