The Stadler class 93 locomotive is a tri mode (diesel/25kV electric/battery) unit intended for both freight and passenger train haulage. Its power is given as 6200 hp on electric traction, 1250 hp on diesel and 540 hp on batteries. Its main purposes is to haul high speed intermodal freight while avoiding diesel running under the wires, with diesel and battery power for the ʻlast mileʼ.
This looks good but is exactly wrong. It is, presumably, a very expensive piece of kit, each one probably costing over £3 million. It that looks like it is brutal on the track - tiny wheels and a 21 ton axle load are a recipe for heavy wear.
Freight trains should not be traveling at high speeds. It wastes energy and damages the track - the modern container carriers with small wheels are track-bashers, and modern passenger trains are also destructive to the point that it is becoming a real problem; the poor state of the track is evident on, for instance, the Great Western Main Line.
Electricity does not come out of the sky. Supplies will have to be enhanced to get rid of diesel running under the wires, and overall thermodynamic efficiency goes down.
The advent of this design points yet again to look at using steam as a benchmark. The 9F freight locomotive delivers over 3000 hp when using coal and about 20% more on diesel fuel. The initial cost of a steam locomotive would probably be a quarter of that of the tri-mode and much the same to run.
As a production locomotive, a new design of three-cylinder 2-8-2 would be a stiff competitor, or another build of the proven 9F class, though the track would have to be modified to allow them back on the national network.
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