The quest for zero-emission technologies in the rail industry has reached a critical juncture. Without a committed effort to replace end-of-life fleet assets with a universally implementable zero-emission power solution, the security and economic vitality of this essential supply chain network could be at risk. While rail transport’s inherent efficiencies often shield it from immediate environmental regulation, there is a compelling case to prioritize it.

U.S. railroads support nearly $219 billion[1] in economic output, handling almost 40% of all freight transportation. While some technologies may be feasible for parts of railroad operations, the critical question for governments and railroads is whether adopting multiple technologies and subdividing routes, thus compromising interoperability between fleets and tracks, should be avoided at all costs. This article assumes that such interoperability is crucial for the security and resilience of the U.S. supply chain. Therefore, any power source considered must be evaluated in terms of its cost and viability across the entire rail network.

Currently operating the oldest fleets in history[2], U.S. railroads face decreasing reliability, increasing operating expenses, and the emission of an astounding 42 million tons of greenhouse gases annually. Historically, rail transport produced fewer emissions than trucking, but this advantage is rapidly diminishing as older trucks are replaced with cleaner technologies. A detailed analysis by the California Air Resources Board shows that California’s truck fleet already emits less particulate matter (PM) than trains for equivalent shipments, and trucking nitrous oxide (NOx) emissions were projected to fall below those of trains by 2023[3]. While final data for 2023 is still pending, the trend is unmistakably heading in that direction. The hesitation to replace these aging locomotives stems from uncertainty about which next-generation power technologies can feasibly meet the heavy-duty power and distance requirements of the rail sector.

Experience from the trucking industry highlights a critical concern: the push for battery-electric locomotives as a diesel alternative could actually exacerbate challenges for U.S. railroads. A revealing report by Roland Berger, released on March 19, estimates that nearly $1 trillion in infrastructure spending would be required to support the trucking industry’s transition to battery-electric vehicles[4]. This figure encompasses major investments by utility companies and governments to upgrade networks and power grids. Beyond the staggering, unbudgeted costs, the coordination effort among numerous disjointed entities could take decades. The crucial question is whether there is a more timely and cost-effective path when we consider each heavy-duty transportation sector both independently and as part of a larger whole.

As railroads and regulatory bodies such as the US Environmental Protection Agency (EPA), Federal Railroad Administration, DOE, DOT, and California Air Resources Board evaluate viable paths forward, it is crucial to draw insights from beyond the rail industry. The trucking industry’s recent experiences provide valuable lessons for the rail sector, helping to inform decisions about zero-emission technology adoption.

Insights from ACT Expo 2024: A Reality Check on Batteries for Heavy-Duty Transport

At the recent ACT Expo / ACT News, the trucking industry’s largest annual conference held from May 20-23 in Las Vegas, key industry leaders delivered sobering insights into the current state of zero-emission technologies. J.B. Hunt Transport Services, Inc. President Shelley Simpson highlighted several critical issues with the widespread adoption of battery-electric vehicles (BEVs) in trucking. Simpson emphasized that electrification is not the most feasible near-term decarbonization option due to high costs, limited efficiency, and significant shortfalls in the available supply of electricity[5].

Ryder System, Inc. CEO Robert Sanchez echoed similar sentiments[6], emphasizing that battery-powered technology for higher horsepower applications is still in its infancy. Sanchez compared the current state of BEV technology to the early stages of mobile phones, suggesting that significant breakthroughs in battery-electric technology are still needed to make BEV’s feasible for heavy-duty transportation. He pointed out that converting the current diesel truck fleet to electric would double the equipment and labor required to move the same load, a scenario that is impractical for both trucking and rail.

9 Times the Challenge: Why Trucking’s Constraints are Supersized for Rail

A diesel semi-truck averages 700 to 1000 miles per tank, while the most efficient battery-electric semi-trucks manage about 250 miles per charge. In comparison, U.S. freight trains travel an average of 917 miles between stops[7], and up to as many as 1200 miles. While the average semi-truck boasts an impressive 500 hp, the average train is pulled by a set of 4500 hp behemoths called line haul locomotives. Thus, a battery-powered freight train, under optimal conditions, would travel only about 28 miles[8], transforming the world’s most efficient rail network into its least efficient.

The rail industry stands at a crossroads: should it leapfrog battery-electric solutions, learning from the hard-learned lessons of the trucking sector?  The evidence overwhelmingly suggests that pursuing battery-electric locomotives might be a futile endeavor. If the pitfalls and inefficiencies are already known, why promote, or worse, mandate such a solution for rail? It’s imperative to evaluate these constraints critically. Here are some of the most pressing challenges that locomotive operators and regulators can learn from the trucking industry’s experience:

• Electricity Demand: Research from the American Transportation Research Institute indicates that fully electrifying the 276 million registered trucks in the U.S. would require 40% more electricity than the country currently generates[9]. This is particularly alarming for the rail sector, which operates 38,000 locomotives across a sprawling 140,000-mile network. U.S. Railroads require a singular, reliable power source and a substantial supply of energy to transport the 1.6 billion tons of goods they handle annually. Given their enormous power demands, there simply isn’t a  near-term path to a sufficient supply of electricity for powering trains with batteries.
• Charging Frequency: Simpson pointed out that the charging time and frequency required for electric trucks render them less productive than their diesel counterparts. This challenge is even more significant for railroads. U.S. railroads, which move about 40% of all U.S. freight shipments, depend on a highly efficient and intricate routing system that supports over 5,000 train routes daily[10]! The U.S. boasts the world’s most efficient freight rail network, averaging more than 5,000 ton-miles of freight per person annually, compared to just 500 ton-miles per person in Europe. Introducing battery swaps or charging stops, even briefly, would drastically reduce the efficiency of U.S. railroads to an estimated 155 ton-miles per person based on the distance capabilities of currently available battery technology, crippling the vital pulse of the U.S. supply chain.
• Cost: Operating costs are a significant concern, stressed Sanchez. Ryder performed a Total Cost of Transport analysis[11] between diesel and battery-electric. The results were staggering – with cost increases of 94% to 114% to convert heavy-duty diesel truck fleets to EV’s. This economic strain would be even greater for railroads, given their oversized equipment, horsepower requirements, and extremely robust operating demands.
• Infrastructure and Efficiency: As with trucking, the rail industry must consider the practicality and efficiency of the infrastructure required for any diesel-alternative source of power. While large truck fleets can run on multiple types of fuel, a one-size-fits-all approach is imperative for rail. Trains can’t simply cross the street to refuel at a different station. Additionally, the industry cannot feasibly replace all its locomotives at once. New locomotives powered by alternative technologies should be able to operate alongside diesel locomotives for an entire 30-year lifecycle to allow for a realistic and affordable transition.

What’s Working for Trucking? The Surprising Role of Cow Poop

• Advancements in Trucking: Both Simpson and Sanchez highlighted the value of using newer, more fuel-efficient vehicles and biogenic fuels like renewable natural gas (RNG).
• Cow Poop Power: Renewable Natural Gas (RNG), produced from organic matter like cow manure, accounted for an astounding 97% of all on-road fuel used in natural gas vehicles in California in 2023 with a Carbon Intensity (CI) of -126 [12], the only biofuel that is negative.
• Economical: RNG is the most substantial, mature, and economical renewable fuel source available, making it the preferred decarbonization method for heavy-duty transport providers.
• Scalable Supply: Following processing, RNG can be injected into existing natural gas pipelines and blended with conventional fossil-based natural gas. This approach ensures an economical fuel cost while enabling achievable supply growth through blended sources of natural gas, resulting in zero carbon intensity.
• Inconceivably Efficient Transport: Pipeline-based fuel delivery for RNG establishes a highly efficient fuel transport system, uniquely advantageous for railroads, as natural gas pipelines run along railroad rights-of-way.
• Incremental Cleanliness: As the proportion of renewable natural gas in the pipeline increases, the fuel used by locomotives and other consumers becomes progressively cleaner with no additional effort required.
• Established Technology: Natural gas vehicle technology is well established. As of January 2023, there were over 175,000 natural gas vehicles in the U.S. and more than 23 million worldwide[13].
• High-Mileage Suitability: Natural gas-powered engines are well-suited for high-mileage fleets that are centrally fueled, providing similar horsepower and acceleration to conventional diesel engines.
• RNG for Railroads: RNG-powered locomotives offer a viable near-and-long-term  solution for railroads. These technologies are affordable, reliable, readily available, and capable of achieving zero emissions without the significant drawbacks associated with current battery-electric vehicle technology.

Conclusion: Pragmatic Innovation for Achievable Impact

True innovation in the rail industry comes from a practical assessment of the entire transportation network. Rather than banking on future technological breakthroughs, the rail sector could save time and expense by assessing cost and performance of technologies that have already been tested in the trucking sector. Leveraging insights from trucking, railroads can identify and support near-term locomotive technologies and low-carbon fuels that decrease overall operating costs and enhance efficiency. Key lessons from trucking include:

1. Invest in the Latest Fuel-Efficient Vehicles: Dramatically lower fuel costs by using the most advanced, fuel-efficient models.
2. Utilize Proven Technologies: Ensure customer support and service excellence by deploying reliable and well-established technologies.
3. Prioritize Low-Cost, High-Supply Fuels: Focus on the most economical fuels with ample availability.
4. Consider Infrastructure Costs and Timelines: Account for both transportation and refueling infrastructure in your analysis.
5. Leverage Sector-Specific Efficiencies: Assess and exploit natural efficiencies unique to the rail sector for significant gains in performance and cost-effectiveness.

By taking these pragmatic steps, the rail industry can make a more immediate impact on emissions while maintaining operational efficiency and economic viability.

[1] https://www.aar.org/wp-content/uploads/2018/05/AAR-Economic-Impact-US-Freight-Railroads.pdf

[2] https://www.bts.gov/content/class-i-railroad-locomotive-fleet-year-built

[3] https://ww2.arb.ca.gov/resources/fact-sheets/truck-vs-train-emissions-analysis

[4]https://www.tanktruck.org/Public/Public/News/2024/Clean%20Freight%20Coalition%20Releases%20Landmark%20Study%20on%20Cost%20of%20Supply%20Chain%20Electrification.aspx#:~:text=The%20report%20suggests%20that%20the,of%20battery%2Delectric%20commercial%20vehicles.

[5] https://www.truckinginfo.com/10222249/j-b-hunt-president-there-are-better-ways-forward-than-electrification

[6] https://www.truckinginfo.com/10222271/ryder-bridging-the-cost-parity-gap-between-diesel-and-electric-truck-operations

[7] https://en.wikipedia.org/wiki/Rail_transportation_in_the_United_States

[8] https://www.railwayage.com/mechanical/locomotives/ze-passenger-locomotive-power-by-the-numbers/

[9] https://truckingresearch.org/2022/12/charging-infrastructure-challenges-for-the-u-s-electric-vehicle-fleet-december-2022-full-report/

[10] https://railroads.dot.gov/rail-network-development/freight-rail-overview

[11] https://www.ryder.com/globalassets/media/documents/insights/white-papers/fleet-management/white-papers-ryder-ev-study_ada.pdf

[12] https://ca-rta.org/rng-a-proven-solution-for-decarbonizing-californias-transportation-sector/#:~:text=In%202022%2C%20RNG%20accounted%20for,gallons%20(DGE)%20was%20RNG.

[13] https://afdc.energy.gov/vehicles/natural-gas