Researchers from Lawrence Berkeley National Laboratory and the University of California just found that battery-powered trains could become economical until 2023. In their paper, the group argues that improved battery technology and cheap, renewable energy could very soon allow battery power to compete with diesel fuel to power trains. Federico Zenith has published a News & Views piece in the same journal issue outlining the reasons for converting trains to battery power and gives an overview of the work done by the team so far.

Zenith notes that trains haul approximately 40% of intercity freight in the U.S., and sending things by train is cheaper than using trucks. He also added that most of the freight trains in the U.S. run on diesel fuel, spewing approximately 0.6% of total U.S. carbon emissions. In this new effort, the researchers suggest that switching to battery power could possibly prevent these emissions.

Electric trains in the U.S. get their power from overhead lines. The team suggests that batteries could provide a better option. More specifically, they claim that a single locomotive equipped with a 14-megawatt battery system would be sufficient to replace a train powered by a diesel engine. They also noted that such a locomotive could carry a train approximately 240 kilometres on a single charge. This would consume half the energy of a diesel-powered train. And if the battery is charged using a renewable resource, it would reduce the carbon footprint of an electric train to zero.

It was also noted that current diesel locomotives actually run on electricity and the diesel is used to power onboard generators. Thus, all that would be needed for most locomotives would be to replace the generators and add a dedicated boxcar. If more dedicated boxcars with batteries are added, this can lead to an increase in the range of the train. Researchers further noted that the batteries could be charged at designated stops, provided fast-chargers for such large batteries are developed.

As an alternative, battery-carrying boxcars could be swapped out for fresh ones at designated stops, drastically reducing wait times. The researchers acknowledge that for the near future, operating costs would be somewhat higher for battery-powered trains, but they suggest the environmental improvements would make it worth it.