De electrification

"Cé hé sin" (michael-m-mouse) 12/31/2018 at 15:25 • Filed to: Class 769, EV, Diesel, Trainlopnik

5

4

It has been revealed to us in recent years that the diesel engine is the fount of all evil. Global warming, Brexit, the end of life as we know it - they’re all the fault of compression ignition.

If you have diesel vehicles you’re going to want to improve your green credentials by replacing them by EVs then. Unless of course you plan to do precisely the opposite.

Meet an EV. It’s a Class 319.

It’s powered by four electric motors which drive each of the four axles under one of the cars. These get their electrons either from overhead cables as here or from a third rail. Why two modes? Because 319s were used on the London to Brighton run which was converted from overhead to third rail around 1930 and remains thus converted while the rest of their route is overhead.

Posters were better then.

The Brighton run was at one time operated by the Brighton Belle, an example of which has been restored:

But that was then. Now the 319s have been replaced by new units and as they’re still serviceable their owners have been looking for new customers. That would have been straightforward enough except that electrification has not gone according to plan (it’s really expensive) and so 319s would be more marketable if they were diesel. That’s curable , with money .

Take one 319 and screw two of these in, one at each end into the invitingly empty spaces you can see in the first picture , and call the result a Class 769. It’s now a tri mode vehicle because you still have overhead and third wire capability.

They’re MAN diesels of 390 kW, so 780 kW for the pair, and run alternators which supply power to the original motors. By the time you take account of inefficiency and the need to provide heat, light, compressed air and so on they provide about 550 kW to the motors which is only enough to provide about half the power available when running on mains electricity. It’s enough for a maximum speed of about 87 mph as compared to 100 mph on the mains though and it’s sufficient for many potential users.

This begs the question as to why they didn’t fit bigger engines. They don’t fit, is the simple answer. A diesel engine, alternator, exhaust and emission systems, cooling system and fuel tank take up a lot more space than an electric motor and even when you take up the space under two c ars you still only have half the power of a set of motors which fit under one car.

So there we have it. The Anti T esla, an EV converted to diesel. Who’d have thought such heresy could be permitted?

djmt1 > Cé hé sin 12/31/2018 at 16:13

1

#Puts railway enthusiast hat on#

For starters The Brighton Mainline has been 3rd rail only for almost 100 years a bit longer than the 319s have been in service. As for why the 319s are dual voltage, it because they ran Thameslink services which run north-south through London. South of London which has the largest 3rd rail network in the rail and North of London is overhead lines requires the switch over as seen below:

As you said electrification hasn’t gone to plan (what has railway wise on this island) and right now we have a chronic shortage of DEMUs and all the diesel locos are caught up with freight duties (this problem is starting to bleed over to electric locos as well, so more Class 90 passenger services, boo).

As for the 319s’ future , it get weirder still since they alongside the 321s are in line for a hydrogen upgrade.  

facw > Cé hé sin 12/31/2018 at 17:02

0

Here in the US, railroad electrification is nearly non-existent outside of the Northeast-Corridor (From DC to Boston). There used to be thousands of miles more of electrified freight lines, but most of those have been decommissioned. I think if you wanted to expand passenger service, there’s a good argument for using diesel first and then electrifying where there is demand. Diesel’s not great for the environment, but the biggest issue is using it in urban cores, which the hybrid power supply nicely side-steps.  

Cé hé sin > facw 01/01/2019 at 15:57

1

There’s also the possibility of battery power to carry an electric train over non-electrified sections, like this Bombardier prototype which is expected to achieve a battery range of 4 0 km in its current form and up to 100 km later this year :

If you want to go longer distances electrically without the expense of wiring, fuel cells present themselves as an option. This Alstom design has already been ordered and two pre-production models are in service :

It’ll travel up to 1,000 km on a fill.

facw > Cé hé sin 01/01/2019 at 16:15

0

The fuel cell train is interesting. The battery one probably wouldn’t be of much use here, as it’s not like there are unelectrified pockets, it’s just that almost nothing is electrified. Only place where I could see it being helpful is to allow an electrified commuter rail line to be able to send trains a couple stops beyond the limit of their electrification.

I think probably any new intercity trains outside of the NEC are still going to have to be Diesel for a while. Bombardier did test a turbine powered version of the Acela a decade or so ago, but obviously it was not a success: