I think existing electric locomotives are more powerful than existing diesel locomotives.
The "most powerful diesel–electric locomotive model ever built on a single frame", the EMD DDA40X, provides 5MW.
The EURO9000, "currently the most powerful locomotive on the European market" provides 9MW under electric power.
USA-made locomotives are so far down the list on https://en.wikipedia.org/wiki/List_of_most_powerful_locomoti... that I suspect there's some other reason they're not needed, e.g. spreading the braking force across multiple locomotives throughout the train.
Trains run on rails, which doesn't exactly allow them to go off-highway. If you're already spending a fortune on building the rail infrastructure, why wouldn't you spend a few bucks extra to install the extension cord?
The "most powerful diesel–electric locomotive model ever built on a single frame", the EMD DDA40X, provides 5MW.
The EURO9000, "currently the most powerful locomotive on the European market" provides 9MW under electric power.
USA-made locomotives are so far down the list on https://en.wikipedia.org/wiki/List_of_most_powerful_locomoti... that I suspect there's some other reason they're not needed, e.g. spreading the braking force across multiple locomotives throughout the train.