On Mon, 28 Nov 2005 12:35:40 +0000, Matt wrote:

On Mon, 28 Nov 2005 11:27:55 +0000, The Natural Philosopher
wrote:

On Fri, 25 Nov 2005 23:50:09 GMT, dennis@home wrote:

The electricity isn't wasted at night.

Actually it is.

The power stations are essentially idling at the great traffic lights of
consumer demand. Since they take a LOT of hours to come on line, they have
to be left at idle.

With the exception of (the majority of) UK nuclear plants that have
specific problems with load changes down and then rapidly up, the
installed generating capacity in the UK (even the 500's and 660's coal
plants installed in the 60's and 70's) are perfectly capable of being
shut down or run on very reduced load overnight and return relatively
rapidly to load next morning. They don't like doing it and it is
wasteful in some respects - hence why some power stations have in the
past bid into the system at zero cost (they got paid the system
marginal rate) which works right up until the point at which the load
drops unexpectedly, the system marginal bid is zero and nobody gets
paid - it has happened!

Exactly they don;t like it and its wasteful.

Thert is a difference between shutting down - going 'cold' - and going to
'standby' , A BIG difference. Some power stations take a week to bring up
to speed from 'cold'. Standby means they are simply turning over, possibly
not connected to the grid at all, but still with heat being generated and
watsed and combustion going on.

It takes HOURS to get a steam boiler up to pressure. Only gas turbines are
relatively quick.