In article , Terry Harper
writes
There would
not be a standby generator, but a standby power station. Think in
terms of the size of some of the old ones.

Yes, it would be a big gas turbine. Would a few hundred MW be adequate, do
you think?

Dinorwig (Llanberis) was designed as a power station for fast backup.
1,728MW available within 16 seconds, apparently.
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Roland Perry wrote in message .. .
In article , Terry Harper
writes

Yes, it would be a big gas turbine. Would a few hundred MW be adequate, do
you think?

Dinorwig (Llanberis) was designed as a power station for fast backup.
1,728MW available within 16 seconds, apparently.

Strictly speaking Dinorwig was not designed as a backup generator, nor
is used as one, as it is powered from pumped hydro storage and thus
has a finite time from which it can provide useful energy conversion
before the head of water becomes exhausted.

Its purpose is to provide additional generating capacity during peaks
in demand of the sort created by the nation putting the kettle on
during the middle of soap operas, footie etc. This prevents the system
frequency from sagging to the point of shedding load. On a typical
day, the plant at Dinorwig may only generate electricity for as few as
10 minutes or even less, some of the remainder of the time being used
as a pumping station to restore the reservior's head.

To provide the ability to go on line and generate 1.7GW in 16 seconds
with fossil or nuclear fuelled plant would require an installed
capacity of perhaps 8GW and the associated costs of keeping it in
spinning reserve until called upon.

As Dinorwig and other pumped storage schemes are used to support the
Grid's stability during transient load flows, they are classed as
power compensation plant and as such are operated in England & Wales
by NGT (National Grid Transco), the transmission system operator.

Richard

On 31 Aug 2003 05:37:32 -0700 someone who may be
(Richard Catlow) wrote this:-

Strictly speaking Dinorwig was not designed as a backup generator,

It would also be slightly difficult to claim that any such scheme is
a generator, because it consumes more electricity than it generates
(unless there has been a change in the laws of physics since I
studied the things).

That is not to say that such a scheme is not very useful however. As
your figures showed it is a good investment compared to
alternatives.


--
David Hansen, Edinburgh | PGP email preferred-key number F566DA0E
I will always explain revoked keys, unless the UK government
prevents me using the RIP Act 2000.

In article , David Hansen
writes
Strictly speaking Dinorwig was not designed as a backup generator,

It would also be slightly difficult to claim that any such scheme is
a generator, because it consumes more electricity than it generates
(unless there has been a change in the laws of physics since I
studied the things).

Sometimes it generates, sometimes it soaks power up. Just like a UPS.
--
"now, the thing you type on and the window you stare out of are the same thing"

In article , Richard
Catlow writes
Strictly speaking Dinorwig was not designed as a backup generator, nor
is used as one, as it is powered from pumped hydro storage and thus
has a finite time from which it can provide useful energy conversion
before the head of water becomes exhausted.

These are all characteristics of a UPS.

I'm not sure how important it is to make a distinction between:

Generating capacity failing to cope because a power plant has
tripped

and

Generating capacity failing to cope because demand has step-
function increased.

The first is very much a "backup", but the second (without an identical
extra source of supply) would have caused the grid to fail.

Over to you.
--
"now, the thing you type on and the window you stare out of are the same thing"