Al Gillis wrote:
> Hi Wes ...
> I know the Great Northern Railroad used electric locomotives through
> mountain passes in Washington State because electrical locos could out
> pull steam locomotives on the steep grades encountered there.
> Thanks!
> Al
The GN's electrification (it was in their Cascade mountains crossing),
which was 11kV 25Hz AC from 1928-1956, was installed due to safety
concerns inherent with running trains through long tunnels, mainly
relating to what to do about the exhaust from locomotives. Remember
that GN opened a very long tunnel there in early 1929. In 1956, the
electrification was scrapped in favor of installing ventilation
equipment in the tunnel. Several of GN's electric locomotives were
then sold to the PRR and with only minor upgrades, were placed into
heavy freight service on their lines.
BTW, before 1928, the GN had a much shorter electification using an
interesting 3 phase system, using two overhead 'trolley' wires and the
rails as conductors on an older line that that 1929 tunnel replaced.
The 3 phase system only operated through the previous shorter tunnel
and into small yards at either end of that tunnel and was used because
the two wires being spaced farther apart allowed a safe place for
brakemen to walk on top of the cars.
One interesting advantage for electric operation in mountainous
regions was that the kinetic energy built up by a train ascending the
hill could then be reused by the railroad through regenerative
braking, using the locomotives' traction motors as generators to feed
that built up energy back into the wire as that train descends the
other side of the hill, controlling the train's speed on its descent
and helping to lift the next train up the hill. If there was no
ascending train ready, the railroad was also able to store that energy
by pumping water into a reservour to be used later.
Also, the Milwaukee Road's much more extensive electrifications out
west used an amazing (in that it worked) 6kV DC system.
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Regards, | |\ ____
| | | | |\
Michael G. Koerner May they | | | | | | rise again!
Appleton, Wisconsin USA | | | | | |
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Michael G. Koerner (