Like most of us who participate in this forum, I would be delighted to see new locomotives with Alco power... but I don't see it as a very likely event. Some posts back, I wrote some reasons why I think it is unlikely, and Alcoman wrote a rebuttal to my post, making a number of good points. In the interests of reasonable discussion (i.e.: LIGHT, not HEAT!) of this fascinating, though speculative, topic, here is my re-rebuttal.
Alcoman wrote:1) While the Gen-Set has up to 3 small diesels, I suspect that if you need to run all the diesels(3) at full throttle all the time, you would be be using far more fuel than 1 Alco diesel rated at 2,000 horsepower.
----We are in full agreement on this. The large, railroad-style, diesel has an intrinsic efficiency advantage over smaller ones (think: surface-area-to-volume ratios of cylinders, given that a major source of inefficiency is heat-loss through cylinder walls)... IF they are both running at full throttle. My point was that in switching service, the locomotive is running at full throttle only a small proportion of the time, and one or more of the "truck engine switcher"'s engines can be shut down entirely when not needed. Which would be more efficient in a particular assignment? I think you'd need detailed figures on the duty cycle of that assignment and a computer to work it out!
Alcoman wrote: 2) Shortlines cannot afford huge parts inventories of many different makes of locomotives. Those railroads often standardize on one or two makes. If the railroad already uses Alco products, it would make better sense to have an Alco product that would fit in with the rest of their fleet.
----Two problems with this argument. One is that, if the small-engine loco is really a "truck engine" switcher, the shortline doesn't NEED to keep a parts inventory: something breaks, you just send someone in a pickup to the nearest truckstop! We live in a truck-dominated economy, and (though I've never seen this suggested in print) one possible selling point for the small-engine locomotive might be that it takes advantage of the infrastructure already in place to sujpport highway vehicle maintenance. Second problem, alas, is that Alco locomotives are gradually getting older and rarer: there are few shortlines now, and we can anticipate fewer in the future, with Alco diesels in their fleet, Alco parts in their engine house, and Alco-skilled mechanics on staff. ;-(
Alcoman wrote: 3) While I don't know how long a diesel in a Gen-set will last, I suspect that a Alco diesel could out last it by a large margin. Alco diesels go about 500-800,000 miles between required overhauls. Plus the Alco could be rebuilt many times over giving it a life span of about 60 years. Alco Parts are easy to find and still be made. Can the above be said about Gen-set engines?
----Something for the bean-counters and the computer here. High-speed engines almost certainly wear out faster than medium speed (assuming both are well maintained). They are also MUCH cheaper to replace. Not being a bean-counter and not having the appropriate software (or quantitative data), I can't say which aspect is more important economically.
(Skipping one because I have nothing to say in response.)
Alcoman wrote: 5) One advantage in using the Alco diesel vs a Gen-set is the weight. Some say that traction control on a Gen-Set may work as well as a heavier diesel. Maybe so, however if you have a Alco locomotive with good traction control, it could out perform the Gen-Set especialy on grades and other difficult situations.
-----This is making a virtue out of a necessity. It the added weight of the medium-speed engine is needed for traction... well, weight can be added in many ways. Concrete blocks, for example. Or (if the hybrid idea appeals for other reasons) storage batteries.
(Thanks, Alcoman! I appreciated your reply to my post; sorry to take so long about re-replying.)