Hybrid Power HST

[BR7MT]

The Network Rail NMT HST is to get hybrid power courtesy of Hitachi

http://business.guardian.co.uk/story/0,,1923155,00.html



Regards,

Dan

[johncard]

Very nice!

[AlistairW]

Maybe if they turned the engines off more often they'd cut emissions.

Any progress seems good, but surely the tests will vary depending on the number of starts the average powercar does? For example, a test train that runs at a speed of say 60mph but doesn't stop for 200 miles isn't going to save much at all, bar the fact there’s the added weight of a battery. Of course the more it stops I guess the more it saves.

The beginnings of HST2 anyone...?

[arabiandisco]

Since the NMT is generally supposed to run non-stop as much as possible, it might not provide any vast savings in that respect (though as I understand it, the diesel engine will be off at speeds of less than 30mph). But I am impressed at the possibility of trying out these new technologies - has to be done at some point, so why not now...

[AlistairW]

It will make stations a much more pleasant environment as well, may also cut breakdowns as if the battery failed I assume the diesel engine could do the work and if the diesel engine failed the battery could at least move the train to the next station.

[CSRZiyang]

Two observations....

1/ What about all the diesel powered energy that will be wasted, hauling those heavy batteries around at speeds above 19 mph?

2/ Wouldn't if be better to introduce a small (say 500 kVA) continuously running auxiliary diesel engine, to drive all the auxiliaries? That way, you could cut the traction power unit when traction isn't required, remove the batteries from all the trailer cars (thus reducing train weight) and use the waste heat from the aux engine to keep the water warm on the traction power unit, so that it doesn't need any electric pre-heating. One in each power car on an HST2 / IEP / ICEPT... whatever it's now called would provide redundancy. Oh, and the traction power unit could be marginally smaller (on an MTU engined HST it would probably make the difference between the 16V and the 12V).

[mattvince]

Weight will be an issue - but as with everything, there has to be a balance - a trade-off between higher energy usage at higher speeds and energy efficiency at lower speeds. No doubt Hitachi and Network Rail will want to look at the various options for how to use the batteries most efficiently - whether it is:
- using 100% battery power at low speeds and using the diesel at higher speeds, or;
- using the batteries for accelerating, and using a smaller, more fuel efficient engine running at a constant rate.

As an investigation into the full-scale use of traction batteries, it's an experiment which has to be done - simply to find out whether it works in real life. There has to be some means of using the energy presently dissipated in an HST's brake-discs for better use - whether that is feeding energy for ETS batteries, traction batteries, or perhaps into a future traction ultracapacitor remains to be seen. The technology may also be incorporated into other propulsion methods - ISTR reading that Fuel-Cells work best with a constant supply of hydrogen, so a hybrid set-up may be preferable to efficiently use that energy.

2/ - I can see that causing more headaches (not least for the Depots) than it solves. It still means you need to power up engines prior to when you wish to depart, rather than waiting until clear of the station to power up. In truth, most station dwells away from termini are short, so the energy saving is minimal - in termini, it may be more efficient to plug in the shore-supply than keep an engine turning. And what about recovering energy from braking?