Interesting! The diesel-electric hybrid. My expectation was based on a trip on the Amtrak Crescent to Philadelphia. We stopped in Washington Union Station to change the diesel locomotives that had been in use since New Orleans to electric locomotives. The conductor told us the switch was due to air quality concerns in the northeast, and also the lack of infrastructure in the south. I also looked at the article about the second-most-powerful locomotive in the list, the 2ES10, since the #1 doesn't have an article yet. The photo shows overhead wires and there is no mention of diesel. I haven't found a good source showing how common the different engine types are. I also think Tesla motors are direct drive with no gearing. It seems like a good balance to have torque at low speeds for acceleration, and less torque at cruising speed when simply maintaining speed is more typical.AFAIK most electric motive locomotives use diesel engines to turn a generator to produce the electricity.
