In article ,
Corporal Jones writes:
I notice on grid watch the power requirement at the moment (17:30) is
55.41 GW.
Nuclear as usual is flat out, Coal is rising and looks near its limit,
CCGT (I presume this is gas) also looks to be near its limit and Wind,
well as usual when it is needed it is rubbish.
The other generation and imports does not amount to much.

Just How much can the UK generate in GW and how near are we to its
limit, also what happens if we go over our maximum generation limit?

Firstly, assuming there's no more scope to import anymore, some
large industrial consumers are cut off - they buy electricity
at a cheaper rate on the condition it can be cut off when supplies
are short. (Same happens for some gas customers, and since gas is
used to generate electricity, this often happens together as
a shortage of one can cause a shortage of the other.)

The other thing that can be done is a reduction in the supply
voltage, but this is nowhere near as effective today as it was
10 or more years ago, as many more loads are constant power.

Having lived through some earlier periods of shortage, a plea
to use less is likely to go out in the media.

Ultimately, if these measures don't resolve any shortage, then
we're into planned rolling power cuts. If the loss of supply
is unplanned (e.g. a power station drops off when there's no
spare capacity), then you get unplanned load shedding - an
area will be cut off to keep the rest of the grid running.
This will either resolve by restoration of the supply, or it
will turn into planned rolling power cuts if the supply
can't be increased (and none of the above measures can make
up for it).

As I've said before, we're probably coming to the end of a
long period (decades) of reliable supply in this country,
because we haven't maintained the investment prior to
privatisation of the industry which got us into the position
of having one of the most stable supplies in the world.

--
Andrew Gabriel
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