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.

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

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.”
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'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.”
More Fuel Smarts

Kempower Adds Flex EV Charger to Help Support Transition to Megawatt Charging
The Kempower Mega Satellite Flex has both a CCS and MCS connector, allowing operators to serve both types of heavy-duty vehicles.
Read More →
Hino Adds Electric Class 6/7 Truck
Hino says the Le Series is an important step in the company's efforts to reduce environmental impact and support its customers’ sustainability goals.
Read More →
Can Multi-Speed EV Transmissions Solve Heavy Trucking’s Biggest Electric-Vehicle Problems?
A startup called Sigma Powertrain believes purpose-built multi-speed gearboxes can boost efficiency, reduce battery size and improve gradeability for heavy-duty battery-electric trucks.
Read More →
Hendrickson Debuts Electraax E-Axle for Medium-Duty Trucks
Developed with Driventic, Hendrickson's new integrated e-axle is designed to improve efficiency, reduce weight, and extend range in Class 6-7 EV applications.
Read More →
50 Ways Fleets Can Cut Fuel Costs Now — Without Buying New Trucks
Fuel savings don’t come from one big change. They come from dozens of small ones. Here’s how leading fleets are stacking gains across drivers, routing, maintenance, and more.
Read More →
Top Green Fleets 2026: How Fleets Are Reducing Emissions in the Real World
What works in sustainable trucking today? Heavy Duty Trucking's Top Green Fleets are finding practical ways to cut fuel use, reduce emissions, and keep freight moving.
Read More →
California Launching $1 Billion Electric Truck Rebate Program
CARB says the California Clean Fuel Reward program will begin offering point-of-sale rebates of up to $120,000 for electric commercial trucks starting June 26.
Read More →
Mack Unveils EPA 2027-Compliant MP13 Engine With More Power, Better Fuel Economy
Along with unveiling its EPA 2027-compliant MP13 engine, Mack outlined powertrain changes across its Class 6-8 lineup, including new Cummins-based X10 engines.
Read More →
How Volvo’s New D13 Engine Meets EPA 2027 Emissions Without Sacrificing Power or Fuel Efficiency
Volvo says advances in combustion and aftertreatment helped its new EPA 2027 D13 engine avoid the fuel-economy penalties many once expected from tighter NOx emissions limits.
Read More →
'TCO’s Here.' Tesla Says Electric Semi Economics Are Ready for the Mainstream
Tesla’s Semi chief at ACT Expo outlined production growth, lower-cost models, charging expansion, and why the company believes fleets are leaving money on the table by waiting on electric trucks.
Read More →
