Study: Battery-powered freight trains could improve electric grid reliability

Battery-powered freight trains could improve U.S. electric grid reliability if battery power becomes more common on main carrier lines, according to a study published this month in the Nature Energy academic journal.

The nation’s rail system could serve as a "nationwide backup transmission grid" through mobile containerized batteries if the energy reserves are shared to meet spikes in demand, wrote study authors Jill Moraski, Natalie Popovich and Amol Phadke.

Deploying a rail-based mobile energy storage (RMES) system also could save the U.S. power industry more than $300 per kilowatt-year compared with the cost of building new transmission lines, according to the study.

"We find that RMES is a feasible reliability solution for low-frequency, high-impact events and quantify its cost effectiveness relative to reliability-driven investments in transmission infrastructure and stationary capacity," the authors wrote.

Because of their flexibility, trains are able to quickly respond to extreme weather causing significant power outages, such as the 2021 winter power crisis in Texas. During those severe winter storms, at least 246 people died directly or indirectly as a result of a power shortage for more than 4.5 million homes and businesses.

As both decarbonization and extreme weather events become more common in the face of climate change, the U.S. electric grid needs to deploy zero-carbon generating resources to maintain reliability and become more resilient to disruptions, the authors wrote. A single train can carry 1 gigawatt-hour of battery storage, equivalent to the carrying capacity of 1,000 trucks, making rail transport ideal compared to road transport.

Other researchers have found that incorporating mobile battery storage into the U.S. rail system can increase operational flexibility and relieve transmission congestion with minimal disruption to freight operations, according to the study.