Alright, somebody needs to set me straight on this once and for all: Why is it that electric locomotives require so much more horsepower to move a much smaller train? If two Dash-9s (a combined 8800 hp) can handle a 100+ car long manifest over rolling terrain, why is 8000hp just barely cutting it to move 11 heavyweight cars in the NEC? Just another basic concept I haven't been able to grasp yet, since I know next to nothing about electrics.
Having just read a similair article in a journal, I'll try and explain!
There is adhesion to bear in mind, the fact electrics are usually lighter means they simply don't get the grip on the rails that a heavier diesel does. Plus 2 diesels means twice as many wheels to provide adhesion to get that heavy train moving. And bear in mind that electrics tend to be geared for higher running speeds than diesels meaning their tractive effort to pull a heavy load from a stand may not be as high as a diesel. A 7000hp 125mph geared electric could really struggle to shift a freight train from standing. However, a 4000hp 75mph geared diesel would have a higher tractive effort and probably get it moving better.
However, I don't know whether you have any specialist electric freight locos in the USA, but we have a 7000hp Co-Co (12 driving wheels) heavy electric loco designed purely for freight, and I tell you what, these locos would probably drag the entire amfleet inventory up the Penn incline in the blink of an eyelid!!! There are even more powerfull freight only electric locos in places like South Africa and Russia.......