26 Horsepower magically becomes 40 horsepower? Physics doesn't work that way. Something is still rotten in Denmark.
I think the rational for using a lower HP electric to replace a gas or diesel is that the torque curve is flat. You don't need to rev your engine up to get your torque, thus you can get away with less. I am not sure if that is what you were getting at or not, but that is my understanding of the reasoning.
Looking at the electric car sites, that seams to be the reasoning they are selling as well,