London Banter - View Single Post - The Bletchley Fly-over

[email protected] · April 18th 16, 09:37 PM posted to uk.transport.london

In article ,
(Colin Reeves) wrote:

On 18/04/2016 06:41, Charles Ellson wrote:

More expensive, obsolete, less efficient and it's heading toward 25kV
territory.

just as the DC line does beyond Harrow?

That was electrified over a century ago.

Maybe that line was electrified over a century ago, but lots of the
SE were electrified with third rail, most recently the mainline to
Weymouth (in the 90s?)

Weymouth was only electrified third rail because Bournemouth was electrified
that way in 1967 and it was an extension of that scheme to eliminate diesel
working and increase capacity.

The game has changed completely since then with power electronics. Dual
system power now far simpler to provide. If electrification to Weymouth were
being done now it could well be at 25KV.

"heading towards 25kV territory" is a red herring.

Not in this case. Chiltern route trains will be going to Milton Keynes via
East-West Rail which will involve 25KV running from Calvert if electric. So
they might as well have the maximum length on that system because it is
cheaper to electrify at 25KV for non-urban railways.

--
Colin Rosenstiel