keelhauled said:
The Tier standards haven't got anything to do with fuel efficiency, they're all about exhaust emissions, and while I can't speak for the QSK95 vs the FDL in particular, Tier 4 diesels actually tend to be somewhat less fuel efficient than their immediate predecessors.
I have heard that they are a little better than genesis locomotives and that it has a lot to do with choices made in emissions management that offloaded some of the hit in efficiency, mainly the after exhaust treatment of urea to almost eliminate NOX emissions. It was a design choice that made the engine more efficient and less complex, at the slight additional cost of frequent light maintenance (refilling the urea reserve tank) I’m sure that cycle is about as frequent as refilling sand, so it can’t be that bad. I wonder if they will just let an engine go out of it isn’t done or is it bad-ordered? From my understanding it’s not mechanically required to operate, it’s an after treatment. I guess that depends on local air quality regulations.
Just for reference the genesis locomotive use about 2.2 gallons of fuel for one mile on average across the amtrak system. It’s in their detailed monthly reports, and since until recently their fleet was homogenous a pretty good average. The p-32DM’s only drop their overrunning shoe a few hundred feet from Penn Station (all of MNCR territory is under running) the electric pickup has a negligible benefit to overall efficiency. If I remember from seeing them, the NJT dual modes actually power down the prime mover when switching to the pantograph.
I should also add that, although I think they are all gone by now, the P-42 is 4250 HP, the first Genesis locos (P-40) 250 HP less... And P-32DM 3,200 in all diesel mode.
I have heard the F-40’s gulped a third to half more in fuel. They were older and things improve, and also in providing HEP they had to run at a constant high RPM whereas the Genesis locos throttle down. That alone save a lot of fuel. As much as the Genesis made for more quiet running, I noticed at Hanford a couple of days ago as the train pulled at accelerating rapidly you could barely hear it as more than a gently idling engine as it passed me while pushing the train south towards bakersfield. I would even say it was more pleasant than the sci-fi like noise you get from
inverters and rectifiers and other electrical
noise on some electric motors now days. (yes despite amtrak’s own press, electric engines are “motors” and not “locomotives.” Those are very specific terms and not interchangeable. Even more specifically, old timers call themselves “motormen” not “engineers.”)
