By using this site, you agree with our cookies usage in accordance with our cookies policy. You can always disable cookies in your browser settings.

6+

6+

Union Pacific is modifying the EMD SD24 diesel locomotives for hybrid traction

13 October 2022
Reading time ~ 3 min
EMD SD4 diesel locomotive of the Union Pacific fleet
EMD SD4 diesel locomotive of the Union Pacific fleet. Source: Union Pacific
Litvintsova Olga, Editor of International Projects, ROLLINGSTOCK Agency
Reading time ~ 3 min
Stolchnev Alexey, Russian Projects Editor, ROLLINGSTOCK Agency

USA: One of the largest freight operators in the country and the supplier of locomotive control systems ZTR announced a partnership to convert the old diesel locomotive to hybrid diesel-battery traction at the Union Pacific depot in North Little Rock. The release of the prototype is expected at the end of 2023, and five more locomotives are planned to be converted in 2024.

The hybrid vehicle will be a combination of two EMD SD24 locomotives (produced by General Motors in 1958-1963). One of them will be equipped with a diesel generator, and the second with batteries, as well as power electronic components and control systems manufactured by ZTR. This should allow the locomotive to operate in three modes: diesel traction, battery traction and combined mode. According to Union Pacific, the combined mode will provide an opportunity to improve the traction and braking performance of the locomotive, which will be the best option for operation at a railway yard. It will be possible to recharge the batteries both from the onboard diesel generator and from a stationary power supply source.

In December 2021, Union Pacific published its first comprehensive plan to decrease the negative impact on climate. The operator with a fleet of more than 7,500 locomotives (the average age of mainline locomotives is 21.2 years, and 40 years for shunters) intends to reduce greenhouse gas emissions from the locomotive operation by 26% by 2030. Union Pacific plans to achieve this goal by improving the efficiency of the locomotive fleet performance, including upgrading existing vehicles to higher emission standards and the use of cleaner fuels such as hydrotreated vegetable oils. So, in May, the operator began testing four diesel locomotives with FDL engines, which use a blend of biodiesel as a fuel. The share of biofuel is expected to increase as trials progress.

In addition, in July, Union Pacific and Wabtec entered into an agreement worth more than $1 bln to upgrade 525 AC4400 and AC6000 locomotives, as well as 75 Dash-9 locomotives. The large project assumes that the implementation of the FDL Advantage diesel operation improvement program and modular control architecture will allow to improve fuel efficiency by 18%, increase reliability by more than 80%, and a haulage ability will grow by more than 55%. In addition, Union Pacific has ordered 20 FLXdrive battery-powered mainline locomotives from Wabtec this year.