Allen Hazen wrote:One thing wrong with this idea, I think, is the Alco diesel. It's a big, medium-speed (1100rpm) engine: the sort of thing used on locomotives. My impression is that one of the major selling points of gen-set locomotives is precisely that they get away from this sort of technology: the smaller, higher-speed, automotive-style diesels used are apparently superior for switching service. (Largely, I think, because they can be shut down and restarted more easily: if an engine is going to be used continuously for most hours of the day (as on road locomotives in mainline service), the bigger engine is more efficient, but for the intermittent duty cycle of typical switching locomotives shutting the engine down is more fuel efficient.)
Now, IF you want a diesel engine in the size-range typical of mainline locomotives... The Alco 251 was introduced at a time when EMD was using the 567C and GE was still buying ancestors of the FDL from Cooper-Bessemer. The Alco engine just hasn't had the development investment that the other builders have put into their engines.
A number of thoughts came to mind after reading the above:
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.
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.
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?
4) While development of the Alco diesel has not matched GE or EMD, I believe that FM/Alco is working R&D into this engine.
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.
I do think that the Gen-Set has its place-light duty switching work around industrial sites. But I also believe that there still is a need for med-horsepower locomotives switchers such as Alco to replace older diesel locomotives of this type. Let GE and EMD build the high horsepower road units.