Nashville, Tennessee — March 15, 2026 — The North American Council for Freight Efficiency (NACFE) has released its second report from Run on Less – Messy Middle, Terrain, Technology, and Telematics: The Messy Middle Operations Report.

This report covers operational factors of Run on Less – Messy Middle. The Run measured real-world performance from 14 Class 8 tractors operated by 13 participating fleets across four energy pathways: diesel/renewable diesel/biodiesel, compressed natural gas/renewable natural gas, battery electric, and hydrogen fuel-cell.

Collectively, the trucks logged more than 73,000 validated miles in revenue freight service with Geotab devices collecting data from each truck.

The report contains detailed specs of each truck, their operating characteristics and focuses on the impact of speed, terrain and elevation on the freight efficiency of each truck.

Cross-fleet insights are provided by powertrain as well as a cross-fleet comparative analysis across all fuel types. The data confirms a central reality of the Messy Middle — there is no single technology capable of addressing every freight application with optimal economics, environmental performance, and operational simplicity. Instead, fleets face technology-selection decisions that depend heavily on corridor characteristics, infrastructure availability, payload requirements, and operational priorities. The evidence presented in the report is intended to support a fleet’s decisions with validated performance data rather than projections or manufacturer claims.

“Transparency is the antidote to uncertainty,” said Dean Bushey, NACFE’s director of programs and the report’s lead author. “By putting real-world data behind these emerging fuel types, we’re giving the industry the roadmap it needs to navigate the most complex transition in trucking history.”

Run on Less – Messy Middle confirms that freight decarbonization is not a simple technology swap but rather a complex, multi-decade transition requiring operational adaptation, infrastructure development, and technology-specific deployment strategies. The 13 fleets and 14 trucks demonstrated that each powertrain technology has a legitimate operational envelope where it can deliver competitive performance today — and equally, boundaries beyond which it struggles to match conventional operations.

Diesel remains the benchmark for operational flexibility, daily productivity, and infrastructure independence. Fleets achieved up to 11.8 MPG while covering 500 to 800+ miles daily across varied terrain — performance that alternative powertrains must approach to achieve scale adoption. Renewable diesel offers an immediate decarbonization pathway using existing assets and infrastructure.

CNG/RNG represent established decarbonization pathways capable of handling demanding freight applications — from regional food distribution to heavy-haul tanker operations — with lower carbon intensity than petroleum diesel. Highway-dominant duty cycles with predictable infrastructure access create the operational sweet spot.

Battery-electric technology has passed the demonstration phase for regional and selected long-haul applications. With 565 to 705+ kWh battery packs and strategic charging placement, BEVs achieved 350 to 500+ mile daily operations and demonstrated 875-mile single-day capability. Terrain sensitivity and infrastructure dependence require corridor-specific validation, but viable BEV deployment is no longer theoretical. These results were achieved with early-generation production platforms, and significant improvement in efficiency, range, charging speed, and weight optimization should be expected as BEV tractor technology matures.

Hydrogen fuel cells showed genuine operational promise — stable efficiency and weight advantages — but infrastructure scarcity and cost remain prohibitive constraints. Current deployments succeed through intensive coordination rather than operational simplicity.

“By looking at how these pioneering fleets are working, we can then project what the future might be for the entire industry,” said Mike Roeth NACFE’s executive director.

After analyzing the data, the study team came to the following conclusions.

  1. Diesel remains the operational benchmark. The diesel fleets achieved efficiency levels nearly double the typical long-haul fleet average — up to 11.8 MPG compared to the approximately 6 MPG — while maintaining 500 to 800+ mile daily productivity across varied terrain. This performance, combined with ubiquitous infrastructure, establishes context for evaluating alternative powertrains. Renewable diesel provides a near-term decarbonization option (50% to 80% carbon intensity reduction) using existing assets and infrastructure.
  2. Terrain is the most significant performance variable. Diesel demonstrated terrain resilience with approximately 30% efficiency variation between flat corridors and mountain passes. BEVs showed greater sensitivity, with efficiency variations of 50% to 70% on comparable terrain differences, translating directly to range variation. Route-specific terrain analysis is essential before deployment decisions.
  3. CNG/RNG serves specific duty cycles well. The Cummins X15N natural gas engine demonstrated diesel-competitive pulling power across demanding applications including heavy-haul tanker and triple-trailer configurations. CNG/RNG efficiency favors highway-dominant duty cycles with predictable infrastructure access. RNG sourced from organic waste can achieve carbon-negative operations.
  4. BEV technology is expanding beyond regional applications. Battery-electric trucks with 565 to 705+ kWh battery packs achieved 350 to 500+ mile daily operations, with an 875-mile validated single-day maximum on favorable terrain. Terrain sensitivity, charging infrastructure requirements, and payload constraints require corridor-specific evaluation before deployment.
  5. Hydrogen fuel cells demonstrated operational characteristics but face significant barriers. Fuel cell trucks showed quick refueling and weight advantages over BEVs. However, infrastructure scarcity, high fuel costs, and energy pathway efficiency concerns present substantial challenges for commercial-scale deployment.
  6. Real-world operational data complements specifications. Across all technologies, actual operational performance varied based on terrain, duty cycle, payload, and driver behavior. Specification sheets provide important baseline information; validated operational data helps fleet operators understand performance in specific applications and set realistic expectations.
  7. Daily productivity matters as much as efficiency. Technology suitability depends not only on energy efficiency but on daily mileage capability — the ability to complete freight assignments within hours-of-service windows.
  8. Infrastructure availability shapes deployment options. Charging and hydrogen refueling networks are developing unevenly across regions. Successful deployments require alignment between vehicle needs and infrastructure positioning along freight corridors.
  9. Human factors influence outcomes across all technologies. Efficiency outcomes are shaped by driver training, performance incentives, maintenance discipline, and dispatch strategy. The highest-performing fleets in the Run demonstrated comprehensive operational optimization alongside technology selection.
  10. Fleet strategy benefits from portfolio thinking. Many fleets will operate multiple powertrain technologies in the near- to mid-term, matching each to appropriate applications based on duty cycle, infrastructure access, and operational requirements.
  11. Organizational culture influences technology success. Fleets that approach technology transitions with commitment and adaptability — from leadership to drivers and technicians — demonstrated stronger outcomes in Run on Less – Messy Middle.

This is the second of five reports surrounding Run on Less – Messy Middle. NACFE plans to publish three additional reports throughout 2026 — an emissions report, a TCO report and a final findings report.

Download the report here