Kendall Baten

United States railway electrification using gravity model and population trends: Are we on the right track?

Transportation accounts for 28% of United States emissions, making it the largest sector to address in reaching the 2050 global net-zero goal. Rail is responsible for only 2% of those transportation emissions, yet it moves 40% of the nation’s freight. In contrast, light- and heavy-duty vehicles generate approximately 80% of transportation emissions. This dissertation aims to identify opportunities for electrifying existing rail routes and directing infrastructure investments to expand ridership, while also evaluating potential new routes that could provide alternatives to car and air travel. The objective is to enable strategic implementation of rail development and maximize its contribution to national decarbonization goals.

Amtrak, the sole passenger rail service provider in the US, has goals to double ridership by 2040 and has published the major projects currently underway or scheduled nationwide with a concentration on the Northeast section of the country. Amtrak has determined 2040 as the ridership goal date to be paired with goals of having an all-electric fleet, as well as introducing new routes and stops by 2035, allowing five years for ridership to catch up with their improvements. One of the key challenges within transport planning is the shifting U.S. population patterns, with projected migrations driving rapid growth in regions that currently make limited use of rail infrastructure. This research projects populations to the Amtrak goal year of 2040 to fully understand the requirements for transport that will be relevant over the next 15 years and how improved infrastructure can encourage rail use. Sensitivity testing was completed confirming the plausibility of the results of a 15-year projection.

In transport planning, gravity models use population and distance to estimate travel patterns, making them well-suited for the United States, where vast geography and shifting population trends necessitate planning for future growth. As such, the gravity model provides a foundational framework for identifying where travel demand is likely to be highest and where new infrastructure should be prioritized. This research aims to understand if the current strategy for Amtrak offers the greatest possibility of increased ridership and further identifies routes that, if electrified, would offer the greatest decarbonization benefits. Results show that while Amtrak has been focusing recent investment in the Northeast, areas in the West, i.e. Los Angeles, and the South, i.e. Texas, offer much greater potential for increased ridership and decarbonization.