>>2060801>The clear advantage electrification seems to offer is higher top operating speeds, which is unnecessary for freight.It's higher operating speeds across the board. The horsepower curve is a lot flatter for electric traction and allows more tractive effort at higher speeds. Higher average speeds gives better asset utilisation. E.g. you can get 2x the trains from A to B by travelling at an average of 40mph compared to 20mph.
>The costs of diesel maintenance is reduced, but now there's the cost of maintaining the overhead wire and related equipment and connections to the grid to offset the gains. And it seems very unlikely every subdivision, branch, spur, and yard will be electrified so there will still be a need for a sizeable diesel fleet.You don't need to electrify everything. You can have bi-mode locomotives that allow for switching and EMUs with batteries that allow for movement around the depot.
>>2060802Transmission losses are a factor but ~35% efficiency is beaten out by a combined cycle power plant at ~60%. Even with transmission losses of 10% and locomotive efficiency of 95% (~51.3%). Transmission losses would need to approach 40% to match a diesel locomotive's efficiency.