A freight train, led by several yellow Union Pacific locomotives, hauling shipping containers on a rail line winding through rolling green hills

October 20, 2023

Circular flowchart showing Single Train Performance Simulation, Multi-Train Network Simulation, Probabilistic Cost Modeling, Decarbonization Energy Pathways, Freight Demand, and Infrastructure Requirements all flowing into an Integrated Assessment. Flowing out of the model are: GHG Reduction Potential; Demand, Capacity Infrastructure; Performance; Emissions; Energy; Cost; and Technology Transfer and Outreach. Flowchart is labeled "Achieving Sustainable Train Energy Pathways (A-STEP) Open Source Tool and Applications.As the effects of climate change grow ever present in our everyday lives, engineers and other researchers are constantly seeking new and innovative ways to cut down our carbon footprint — including the ways transportation modes are fueled.

The transportation sector emits the highest amount of greenhouse gas emissions of all the U.S. sectors, according to the U.S. Department of Transportation. The rail sector, in particular, contributes 2% of those emissions.

In a collaboration sponsored by ARPA-E, researchers from NC State’s Department of Civil, Construction, and Environmental Engineering (CCEE) and Institute for Transportation Research and Education (ITRE) have worked with DB E.C.O. North America Inc., Virginia Tech Transportation Institute and Oregon State University, to develop a toolset that can be used to identify ways to reduce freight rail’s carbon footprint, expanding the use of lower emission power sources. A-STEP (Achieving Sustainable Train Energy Pathways) is a first-of-its-kind, integrated, open-source software tool that can help guide freight rail decarbonization decision-making.

“There’s no other tool like this in the public domain,” said CCEE Professor George List, who was PI on the project. “Ten years ago, decarbonization seemed like an unattainable goal. Now, more companies and organizations are embracing the idea; it is becoming technologically feasible.”

A-STEP provides ways to study energy use scenarios for individual trains, networks of trains, battery and hydrogen charging stations, national energy sourcing and pricing, and overall decarbonization costs and environmental impacts. A-STEP gives analysts an ability to study the challenges of making such change happen. Completely amenable to analyst specified inputs and parameter values, it can be customized to provide outputs for a wide variety of assumptions about future energy conditions and technological advances. Written in Python, C++, and VB.Net, A-STEP can be implemented on both Windows and Linux-based platforms.

A-STEP includes five specific analysis tools:

“Adoption of hydrogen fuel and other energy sources is advancing,” List said. “The rail industry is moving this way and will continue growing. One of the next targets is the trucking industry.”

Learn more about A-STEP and download the toolkit here.

The A-STEP project was funded by ARPA-E under the LOCOMOTIVES program. The PIs were CCEE’s George List, Jeremiah Johnson and Eleni Bardaka; Yue Cao (Oregon State University); Andreas Hoffrichter (DB E.C.O. North America Inc.); and Hesham Rakha (Virginia Tech Transportation Institute). CCEE project members included Aditya Sinha, Tongchuan Wei, Mehrzad Mehrabipour, Soumya Sharma, Ahmad Abdallah, Mehedi Hasnat, Emily Boldor, Adam Fleischer, Natalie Hackman, Wyat Hamilton, Logan Kemp and Layla Lukas. Other project members included Ishtiak Ahmed (NC State Institute for Transportation Research and Education); Lynn Harris, Mohamed Hegazi, Christopher Beringer, Rupal Mittal and Andreas Weiss (DB E.C.O North America Inc.); Jianhe Du, Kyoungho Ahn and Ahmed Aredah (Virginia Tech Transportation Institute); and Vinson Guov and Derek Jackson (Oregon State University).

Adapted with permission from: CCEE researchers tackle rail decarbonization with innovative A-STEP software tool