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OptiFuel Systems Statement: Debunking Greenwashing in CARB’s Recent “Zero Emission Train Feasibility” Analysis: Why In-Use Locomotive Regulations May Derail Quickly

by | Jul 9, 2024

BEAUFORT, S.C.–(BUSINESS WIRE)–The following is a statement provided by Scott Myers, President & CEO, OptiFuel Systems.

The California Air Resources Board’s (CARB) recent article, “Feasibility Analysis: Zero Emission Train from the Port of Los Angeles to Barstow”, has sparked significant debate due to its reliance on locomotives that do not yet exist and/or lack FRA concurrence. The article contains technical inaccuracies, failing to adequately address the railroads’ operating and financial implications. My detailed article, “Debunking Greenwashing in CARB’s Recent ‘Zero Emission Train Feasibility’ Analysis: Why In-Use Locomotive Regulations May Derail Quickly”, provides an in-depth exploration of this topic. Below is a summary of key points.

The Core Issue

Just like the CARB In-use Locomotive Regulations, the article focuses on zero emission solutions that are not affordable, not technically available or feasible, and highly unlikely to be operational within the next 30 years. Despite their theoretical promise, these technologies face formidable practical and economic obstacles that would hinder the efficiencies of US rail. This raises a crucial question: if the goal of energy transition is to improve future outcomes, shouldn’t CARB set forth policies that foster the widespread adoption of readily available technologies that meet price and performance parity (P3) levels of current diesel models? Advocating for technologies that cannot reach P3 squanders resources that could instead be directed toward meaningful innovation. It’s time for CARB to pivot towards a strategy that recognizes these crucial elements.

Battery-Electric Trains: A Storage Space Conundrum

Batteries are not primary energy producers; they are energy storage devices. This fundamental characteristic poses a nearly insurmountable physical limitation for long-haul freight operations. The sheer volume of batteries required to match the volumetric energy density (Wh/L) of diesel is staggering and impractical – requiring 50 times more space to store the same amount of energy as diesel. For the average train, this translates to replacing about seven revenue-generating rail cars with battery storage cars for each battery-electric locomotive employed. See more in: full article

Current Development: The FRA-concurrent Progress Rail Joule SD40J switcher locomotive and Wabtec FLXdrive slug, demonstrated in the US, both contain 2.4 MW of lithium batteries. Although capable of generating around 1.5 MW of traction power, they can only sustain it at Notch 8 for about an hour. After this, both systems effectively become dead weight that diesel locomotives must carry for the remainder of the trip. This contrasts starkly with diesel line haul locomotives, which can maintain at Notch 8 (3.2 MW) for up to 29.5 hours, highlighting the significant disparity in operational endurance.

Hydrogen Trains: Supply and Transport Impasse

Hydrogen as a fuel source presents significant challenges, primarily due to availability and transport issues. Currently, 99% of all hydrogen produced globally is gray hydrogen, which has a higher carbon intensity (117) than diesel (104). This exacerbates carbon emissions rather than reducing them, and the virtually nonexistent supply of green hydrogen renders it an unviable near-or-medium-term option. The second major hurdle is transportation logistics. Gaseous hydrogen at 5,000 psi requires 10 times more storage volume than diesel, and liquid hydrogen at -432 F (-252.8 C) requires 4 times the storage volume of diesel. According to the U.S. Department of Energy, it would take up to 14 hydrogen tanker trucks to transport the same amount of energy as one diesel tanker truck. This would necessitate at least 4.2 million new tanker truck loads annually just to refuel U.S. locomotives. These logistical challenges highlight the impracticality of hydrogen as a scalable solution for the rail industry before even considering the associated costs. Additional detail available in: full article

Current Testing: The most powerful hydrogen locomotive in testing, the CPKC 1.2 MW switcher, has an onboard hydrogen storage capacity of around 200 kg. It can only produce 1.2 MW at Notch 8 for 2.15 hours, or about 3 hours when including the power from onboard batteries. This performance is a small fraction of its 4500 hp diesel contemporary.

Overhead Catenary Trains: Scaling Financial Peaks

In CARB’s Feasibility Analysis for routes from the Port of Los Angeles (POLA) to Barstow, segments 2 and 3 were proposed for conversion to Overhead Catenary Trains (OCS), covering 80 miles through Cajon Pass—areas that are triple-tracked by BNSF and single-tracked with sidings by Union Pacific. Projected OCS installation cost is $8-$10 million per mile, with an additional $2 million per mile required for substations and grid connections to a primary power source. This places the total estimated cost for this limited 80-mile section at $1 billion to $1.2 billion. The question looms large: who would shoulder these substantial costs?

Renewable Natural Gas Trains: Price and Performance Advantage

Renewable natural gas (RNG) presents a realistic and attainable solution for the rail industry’s transition to zero emissions. As a 100% renewable resource, RNG can reach zero or even negative carbon intensity, positioning it as a genuinely sustainable fuel option. Railroads are uniquely positioned to harness unprecedented efficiencies resulting from their proximity to the extensive underground natural gas pipeline system, which runs along railroad rights-of-way. Additionally, the infrastructure needed for RNG refueling is both cost-effective and scalable, primarily involving the installation of RNG dispensers at current diesel refueling stations. Notably, one U.S. railroad has successfully utilized this type of refueling system for over five years, underscoring the viability and potential of RNG in railway operations.

Current Development: The highest power RNG locomotive currently under development, the OptiFuel 5600 hp Total-Zero™ Line Haul Locomotive, is capable of producing 3.4 MW of traction power for 6.7 hours with 1750 DGE of RNG onboard. Its switcher variant has achieved FRA concurrence, while the line haul model will start testing in 2025, with approval expected by 2027. These locomotives, powered by EPA certified zero emission locomotive engines, boast an exceptional range: two 5600 hp RNG units with a 11,800 DGE RBG tender can cover 2,500 miles, out-distancing two 4500 hp Tier 4 diesel locomotives by 1,000 miles and demonstrating RNG’s efficiency and capability for rail transport. See detail in: full article

OptiFuel goes a step further with all-in-one programs like Locomotive-as-a-Service (LAAS™), designed to make affordability a reality for any railroad. Through this program, railroads receive a fully integrated solution – including RNG-powered locomotives, tenders, refueling infrastructure, and RNG fuel – for one low, fixed-rate fuel price plus an upfront payment of about 20% of the retail price of the locomotive. For an OptiFuel Total-Zero™ 5,600 hp RNG Hybrid Line Haul Locomotive, this upfront payment would be approximately $1.1 million, covering up to 30 years of use.

The Bottom Line

Rather than chasing unattainable solutions, our focus should shift to technologies that match or outperform existing diesel locomotives in both cost and efficiency. RNG-powered locomotives stand alone in meeting these critical targets, delivering not only parity but also cost savings and superior operational performance. By adopting technologies that surpass diesel, we can ensure the market itself propels the transition to zero-emission rail.

More Resources on this topic are available at: OptiFuel Systems News & Resources

About OptiFuel Systems:

OptiFuel Systems designs and manufactures Total-Zero™ emission products and services for transportation and industrial markets. With expertise in RNG and hydrogen fuels, OptiFuel works as a systems integrator with strategic partners and offers innovative, low-risk, and modular solutions, including locomotives, tenders, refueling systems, and emergency generators.


Scott D. Myers, OptiFuel Systems LLC – (339) 222-7575,