Re: Fate of 85/86 class

["Greg Hunter" <huntergpmj@bigpond.com>]

Maybe this newsgroup has had a win - FreightCorp has started running elec
hauled coal trains from the Blue Mtns to Pt Kembla again. 
There was one 4 loco train on 8/2 (about 0145 through Sutherland) and two
on 9/2  (0130 & 2130)

Just to answer some of the recent questions: 

To move equal size trains over the same route, electricity costs about 1/4
to 1/3 that of diesel fuel. But the savings in fuel costs must be enough to
cover the Capital and maintenance costs of the electrical infrastructure. 
For new electrification, this is only likely to break even if you're moving
 over about 50 million tonnes pa.(maybe a bit less)

But for using 85/86s under existing wire, it's pure savings.(assuming FC
aren't being charged anything for the maintenance of the wire - I don't
know about this)
To take 3500 tonnes from Lithgow to Pt Kembla and the empties back again,
uses about $800 worth of electricity at current rates. (expected to rise by
about 20% soon.) So the savings over diesel would be around $2500 per trip.


Apparently FreightCorp reckons this amount doesn't cover the cost of
changing locos twice at Lithgow. Hmmm?

Others have mentioned that the 1500V system limits the number of locos you
can ultimately use and that the losses in a dc system are must larger than
a high voltage system.  
The first bit is true - the Como- Heathcote section can handle 9 megawatt
trains (12,000 HP) of 4 electric locos in series parallel.  And this is
about as big as any 1500V system could ever go.

The losses in the two systems, running big trains, are not all that
different and not really significant in either case. Electrical systems are
designed to be pushed to their limit by single big trains and ultimately
this means big losses for short times. For the 4 loco trains on the Como
bank losses on the dc system are about 13% but on the overall return trip
less than 5% all up.
An AC system would be designed for the volts to fall to maybe 18 kV so the
losses would be not that much less than dc.



Greg