Technology Works But Is There Not the Pressure to Move Over?
There is quite a bias to the south of England regarding these trains so far. This is a rather insidious bias to the capital with nearly all other Metropoles having the potential application of multi mode tractive power. You can also argue that London is the most electrified of cities and connurbations already, with only Glasgow and Liverpool being near the relative number of trains run on sparky stuff. What though is the future for more complicated trains away from the south east or on minor routes around there? What pull is there towards the technological shift? What are the economics? Why bother?
The Japanese Test On UK Steels
THe unit also was built to run out of station on a dead engine, start engine underway and the take over power. The battery power available was an impressive 1MW, about 1300hp, storage at 481 kwh. This sped the train from a standing halt on battery only to about 50 mph when the engine could then be engaged.
As you see in this image though, the impressive acceleration in the video may be due as much to the fact that this is less than half a working IC 125 train 'set', and the GCR preserved line is hardly known for its gradients. Two tonnes of batteries is a negligible amount to carry slung under a single coach, so you could obviously imagine an 8 car set with two power cars and two battery trailers, pushing out 2MW or in excess of 2600 hp! Also as you can see, this is a prototype system which uses the entire mrk III trailer for electrical control systems and what looks like a large radiator to cool the batteries and high amp machinery. However, this is just at prototype level, and coaches already carry lead acid batteries so the whole system could probably be shrunken to fit under a specially designed coach with more being included in the locomotive power car specially designed for the purpose on outset.
A Realistic Technology for Today Already?
Yet another benefit is a little more technical, but very important. As any train driver will tell you, all trains actually have "gears" and electric or diesel electric are no exception. Electric traction motors eventually start to revolve so fast at the current amps-volts field being applied that they produce an electro magnetic feedback or resistance to further useful power and especially torque to be applied. Rather than grinding away in first gear, a locomotive lets the engine back down to lower revs or idle and resets the circuit to higher voltage such that the new rotational speed of the motors can be matched and more power applied. Most locos have three, or three and a half if you take the initial amp loads into account. Now some routes are terrible for this gear shift happening, both upwards and downwards, especially around the 40-50mph for older locos and some multiple units. For we syphon fans, this was kind of an achilles heel, which meant that while they excelled at both the grunting of the highland routes and the welsh valleys, also on 60 -80 mph services, on routes like the 'Fife circuit' or Inverness-Aberdeen, there are significant sections with just that nasty speed range, 40-50 , so performance was lack lustre unless a driver chose to break the speed limit. With batteries on board you can push through with a more rapid voltage transition (field diversion) maintaining speed and maybe accelerating until the engine streams back on to power the train through. WIth GPS and power management, this also means that stretches at this speed can be handled on battery power providing an optimum voltage output, while they are charged by an engine at higher RPM, or the engine is not used given a duration of battery use which is calculated.