While looking for something else, I found data about a (relatively) new Stadler dual mode (straight electric / diesel electric) locomotive.
Here's a link to a brief English description on Wikipedia:
https://en.wikipedia.org/wiki/Stadler_Euro_Dual
A few points worth noting:
The various versions have Cat diesel prime movers and comply with current European emission standards.
The high-end (Co-Co) version produces over 7,000 hp in straight electric mode and over 3,000 hp in diesel mode -- both are continuous output ratings.
Though designated for freight operation, the high-end model has a top speed of 100 mph.
The Wikipedia article notes one of these locomotives is undergoing testing at the Velim test facility. Velim is the European equivalent of the AAR test center at Pueblo.
-- Ernest