Renewable natural gas is an immediate, economically viable path to long-haul freight decarbonization and fuel stability.
- Economic Advantage: Renewable natural gas (RNG) provides significant operational fuel savings—yielding a cost advantage of 28 to 32 cents per mile compared to diesel.
- Infrastructure Ready: North America features an established network of roughly 1,600 natural gas fueling stations that require minimal compressor upgrades to support high-pressure systems.
- Proven Technology: High pressure direct injection (HPDI) systems allow heavy-duty diesel engines to run on gas while retaining traditional torque, power, and efficiency.
- A Bridge to Hydrogen: Natural gas delivers immediate emissions reductions today while acting as a seamless pathway to future hydrogen and hydrogen-blend adoption.
North American fleets are watching the electric and hydrogen transition unfold with understandable caution. Battery-electric trucks are making progress in short-haul applications, while hydrogen development continues on a longer horizon. But while those technologies dominate headlines, another transition is already happening at commercial scale — not in pilot programs or future projections, but on highways around the world.
Renewable natural gas (RNG) has become the workhorse of global freight decarbonization. RNG production is ramping up in North America and already fuels most on-road natural gas vehicles. Yet only a small share of long-haul transport fleets run on RNG, leaving a massive untapped market opportunity.
Global transition already underway
The global natural gas commercial vehicle market is expanding rapidly as fleets seek cleaner, cheaper alternatives to diesel. A recent report projects the sector will grow to $86.2 billion by 2032, more than doubling its 2025 levels. Asia-Pacific leads with a 46% market share, driven by large-scale adoption in China and India. North America is expected to be the fastest-growing region thanks to stringent emissions standards, incentives, and a broadening refueling network.
Heavy-duty trucks represent 71% of the global natural gas vehicle market share, and freight transport accounts for 42% of revenue — clear signals that natural gas is becoming a central long-haul strategy.
Fleet owners face intense pressure: volatile diesel pricing, thin margins, and uncertainty about which technologies will deliver both emissions reductions and operational stability. Natural gas is increasingly attractive because the economics finally make sense. In fact, RNG now fuels 94% of all U.S. on-road natural gas use, up from just 39% in 2019, according to The Transport Project (TTP).
Converging forces accelerating adoption
Multiple forces are aligning to make natural gas a practical long-haul solution in North America:
- Economic pressure: Fleets want lower emissions, but only when the numbers work. Natural gas prices have remained stable while diesel remains volatile and electricity rates exceed early projections. A recent analysis notes that RNG has a cost advantage of 28 to 32 cents per mile versus diesel's 41 to 53 cents per mile — a 20% to 35% operational fuel savings.
- Technology maturity: High pressure direct injection (HPDI) systems enable diesel engines to run on compressed natural gas (CNG), though at a higher pressure than traditional CNG vehicles in North America, while preserving diesel-like torque, power, and efficiency. Tens of thousands of HPDI-equipped trucks operate in more than 30 countries.
- Infrastructure readiness: Industry analysts expect natural gas to play an expanding role in North American heavy-duty trucking over the next decade. There are now about 1,600 public and private natural gas fueling stations across the U.S. and Canada, according to a recent report. While those are now heavily concentrated in specific states and along major freight corridors, a steady increase of new stations are coming online year-over-year, TTP notes. And while they are already equipped for CNG, only simple upgrades would be needed to handle the higher pressure required by future HPDI-powered trucks.
- Hydrogen's long runway: Hydrogen remains promising, but it will be years before it achieves widespread economic viability. A FleetRabbit market forecast predicts that by 2035, the U.S. could see 5,000 hydrogen-powered trucks on the roads, with 2,000 refueling stations. Natural gas is the bridge fuel that keeps hydrogen pathways open without forcing fleets to delay a transition from diesel.
Why isn't North America moving faster?
If the economics and infrastructure are in place, why are long-haul fleet owners hesitant to make changes?
Regulatory uncertainty is a major factor. EPA27 standards have created a two-year pause as original equipment manufacturers and fleets wait for clarity before investing in new platforms. Adoption cycles also slow progress. Fleets test new technologies for months or years to validate performance and maintenance readiness. Those pilots are underway now, but they take time.
Infrastructure misconceptions persist. Many fleets assume stations cannot support the higher-pressure fueling required by HPDI. In reality, most need only compressor upgrades, a far simpler and more cost-effective lift than the grid build-out required for large-scale electrification.
And finally, fleet owners and their mechanics are familiar with diesel. Moving to a new fuel — whether it is spark-ignited or the HPDI fuel system powered by CNG, battery electric, hydrogen fuel cell, or a dual-fuel approach — can present a psychological barrier, even though city buses and refuse trucks have operated safely on natural gas for decades.
Economic and environmental benefits hard to ignore
Natural gas enables immediate emissions reductions without significant changes to trucks, routes, or fueling infrastructure. It is the rare decarbonization solution that does not require a major capital overhaul.
Our internal analysis of the five-year total cost of ownership of various technologies reveals that HPDI-CNG systems outperform diesel and spark-ignited natural gas engines across multiple mileage bands. RNG's price stability is especially valuable as fleets negotiate annual shipping contracts where margins can evaporate with fuel volatility.
As long-haul fleets complete pilots and see performance firsthand, adoption will accelerate — just as it did in transit (see chart below) and refuse markets, which reached roughly 30% to 50% natural-gas share, respectively, once operators validated the economics.
What fleets need to understand now
Solutions that transform diesel engines with HPDI and CNG can provide long-haul fleets with the same torque, hill-climb performance, and efficiency they expect from diesel, while enabling maintenance teams to work on familiar engine platforms. The technology also provides a pathway to hydrogen and hydrogen blends, without replacing trucks or retraining the workforce.
Natural gas may not be the final destination, but it is the foundational fuel for the next decade: stable, scalable, and capable of delivering immediate emissions reductions while the industry builds toward hydrogen.
How quickly long-haul fleets take advantage of advancing engine technology and natural gas infrastructure already in place is still to be determined. But they cannot afford to wait for the perfect solution. Leaders will act now, adopting a proven, economically sound, lower-emission fuel already delivering results worldwide.
