The main constraint is just lack of electric maintenance facilities, not purchase cost or fleet size. Electrics aren't terribly expensive vs. diesels, and the Providence line requires so much equipment by its lonesome that the number of units would be self-sustaining. But Southampton's the only onsite facility that can serve electrics, and Amtrak itself is tapped out of space there. They're also tapped out of space in their heavy-maint facility in New Haven. The need for a new Boston-area full-service facility and storage yard has been identified in their long-term capital improvement plans as a high-priority necessity for supporting any significant traffic growth to Boston.
If that comes to pass in the next 15 years or so Readville is the dead-obvious choice for such a facility because there's a whole lot of unused yard property already available and no real restrictions on building there because it's always been train yard well-buffered from the neighbors. If the T gave them the empty yard or brokered a land swap with CSX (which probably doesn't want to stay there long-term), then collaborated on a facility with enough growth space that they could both share it ...an electric fleet gets a whole lot more viable. For one, it would free up a lot more needed capacity at BET for a constantly increasing number of diesels on the other lines if they didn't have to service close to a third of the southside fleet anymore. A facility in Providence instead of Boston could also make MBCR electrics worthwhile because in that case RIDOT would also chip in on a likely even bigger facility to serve its South County CR fleet, which is supposed to be all-electric from Day 1.
I think the new electric facility is the trigger that ultimately brings electrics on the CR from the realm of dreams to the realm of practicality. But until Amtrak says it's go time for that there's simply no way to support those locos on the system.
If that comes to pass in the next 15 years or so Readville is the dead-obvious choice for such a facility because there's a whole lot of unused yard property already available and no real restrictions on building there because it's always been train yard well-buffered from the neighbors. If the T gave them the empty yard or brokered a land swap with CSX (which probably doesn't want to stay there long-term), then collaborated on a facility with enough growth space that they could both share it ...an electric fleet gets a whole lot more viable. For one, it would free up a lot more needed capacity at BET for a constantly increasing number of diesels on the other lines if they didn't have to service close to a third of the southside fleet anymore. A facility in Providence instead of Boston could also make MBCR electrics worthwhile because in that case RIDOT would also chip in on a likely even bigger facility to serve its South County CR fleet, which is supposed to be all-electric from Day 1.
I think the new electric facility is the trigger that ultimately brings electrics on the CR from the realm of dreams to the realm of practicality. But until Amtrak says it's go time for that there's simply no way to support those locos on the system.