Locomotives are being built for Union Pacific, Canadian Pacific and major mining companies in Australia.

Paul Gibbens for Wabtec

Change in the freight rail industry is like a lumbering, mile-long train and has to be phased in with care. Locomotive builders and railroads are following in the footsteps of car and truck manufacturers and using batteries large enough to power small towns as a way to curb carbon and diesel emissions.

The world's biggest purchase of battery-powered locomotives and charging systems was made by Union Pacific. The Omaha-based railroad will use trains to pull cars around freight yards in California and Nebraska instead of on cross-country runs, and estimates the mammoth machines could eliminate 8,000 tons of carbon emissions annually. Locomotives haul freight over 480 miles per gallon of diesel fuel per ton if they add batteries. According to the Association of American Railroads, that is up to four times better than the average for trucks.

We are advantaged from a fuel consumption perspective and from a diesel particulate standpoint, but trucks might get batteries sooner, and they will start to creeps up on us. The second-largest U.S. railroad wants to cut greenhouse gas emissions 26% by 2030.

About 2% of the U.S. greenhouse gas emissions come from transportation sources.

Environmental Protection Agency

Billions of dollars are being invested to ramp up production of battery-electric cars and commercial vehicles, with some of the biggest bets being made by General GM, Ford, Toyota, Volkswagen, Daimler, Cummins and Volvo. The mass and power requirements of locomotives make freight rail more complex. The need for more testing of battery systems tailored to their unique requirements is the reason fully electric trains aren't likely in the near term. Even so, the industry is starting from a surprisingly efficient position when it comes to carbon pollution.

Union Pacific ordered locomotives with batteries from Wabtec, but isn't sure if they are durable enough to deploy them on its main, long-haul lines, where multiple diesel-powered locomotives are linked up to pull 150 more rail cars. The railroad wants to use more renewable fuels to cut pollution from its trains. Although hydrogen-powered systems are being developed for lighter passenger trains by Cummins and other companies, the cost of installing new large-scale storage facilities and minimal availability of hydrogen made from low-carbon sources means it is not an option for now.

“The big deal for us is to really drive the emissions reductions–as quickly as we can.” 

Beth Whited, Union Pacific executive vice president for sustainability and strategy

Whited says that technology is a little further behind for our particular use. The railroad would have to invest in a more complex storage and fueling system to switch from diesel to hydrogen. We are paying attention to what is happening with hydrogen. We think it is early.

Some railroads want to see if Wabtec's battery trains can do more than pull cars around a railyard. The Pittsburgh-based manufacturer is readying more powerful machines for Canadian National and Australian mining companies. The batteries are too heavy for semi-trucks, but are fine in locomotives. They will be used to save fuel and cut emissions. In a pilot project in California's Central Valley last year, Wabtec used a pack that cut fuel usage by 11%.

A train with high-powered batteries save on fuel and use regenerative brakes, like a supersized version of those on Toyota's Prius or aTesla Model 3.

We are going to 8-MWh in the near future. We are going to save 30% on fuel usage when we do that. There is a lot of power going into those batteries.

Since its initial California test last year, Wabtec has quickly received orders for 18 battery-powered locomotives. The trains may cost $4 million each, based on Union Pacific's order. The original unit was run in early 2021. The orders are starting to arrive and we are very excited about them.

Los Angeles-based Parallel Systems, led by a trio of former SpaceX engineers, is taking high-tech rail ideas even further with plans for relatively small, battery-powered trains making short-haul freight runs that also can operate autonomously.

Los Angeles-based Parallel Systems is developing trains for short freight runs.

Parallel Systems

The trains of 10 to 50 cars on platforms will be powered by distributed battery packs and will complement typical trains of 150 cars or more rolling on freight rail lines. Positive Train Control is a safety technology that is used across all U.S. freight and passenger rail lines. The precise location of trains can be seen by operators at rail-monitoring facilities. Parallel believes you can run its trains autonomously if you add computer vision and sensors.

Unlike self-driving cars and trucks that have to be ready for an array of unexpected circumstances on city streets and highways on a rail line, you have this central knowledge of where everything is. Positive Train Control helps ensure only one train is operating at a time.

Parallel emerged from stealth in January with a $50 million funding round and in February received a $4.4 million grant from the Energy Department to test its electric freight train platform with federal researchers.

The first 18 battery-powered trains will be built by Wabtec, but it is upbeat about the interest in electric locomotives.

We are not giving estimates at this point but we see it having a good ramp over the next couple of years.