On Jan 25, 6:10 am, (Neil Williams)
wrote:
On Thu, 24 Jan 2008 17:03:56 -0800 (PST), Andy
wrote:

See above, this is one of the delights of having a mixed fleet of
incompatible units.

Not on a Sunday, when there are (I think) only 4 diagrams giving a
half-hourly service, and most of them tend to be 4-car. This is
lunacy given the actual demand.


Does anyone know what proportion of the running costs of a train are
power consumption and how that scales with length of train?

Presumably for trains with few stops the power consumption is
approximately constant regardless of the length of the train because
the main loss will be air drag.

But how far apart do those stops have to be?

I presume trains don't use regenerative braking at all (ISTR some of
the underground trains are now starting to use this)

Tim.