On Mar 22, 4:25*pm, Jethro_uk wrote:
On Fri, 22 Mar 2013 14:16:21 +0000, Tim Watts wrote:
On Friday 22 March 2013 13:39 Jethro_uk wrote in uk.d-i-y:

On Fri, 22 Mar 2013 12:50:57 +0000, Tim+ wrote:

Andrew Gabriel wrote:
Front page of Friday's Times apparently says we have only 2 days
stock of Gas at the moment, versus the 15 days we normally have...

And we're just heading into several more days of snow across the
country.

I haven't seen a gasometer/gas holder with any significant stored gas
for ages. *Do they get used at all these days or just for "bare
minimum" storage?

Tim

I thought they were designed more to keep the grid at a constant
pressure ? They were busy dismantling them in the 90s - Both South
Harrow and Southall went - they used to have massive letters painted on
them, pointing to Northolt and Heathrow airports respectively.

To be honest, given the bomb-happy nature of every disgruntled citizen
nowadays, I'm rather glad there isn't a huge store of flammable gas[1]
in densely populated areas.

[1]I vaguely recall it would be unlikely to "explode" as we know it.

I thought most gas storage was done by pressurising the UK main "grid"
gas lines (not the street supply obviously).

Linepack. They pump the grid up to 75Bar overnight, and let it "bleed
out" during the day (gas tends to be cheaper after 6pm). Many years ago I
worked on the program which took all the individual contracts (negotiated
individually - there were nearly 100) with the gas companies and had
lower and upper limits, plus cost bands, plus rig shutdown dates, and
weighed the supply against the demand (produced by another program, feed
with telex data from the Met Office) and generated a list of orders which
minimised compressor usage (most grid compressors are RB211s that can use
enough gas in a day to supply a small town).

But that's the national high pressure grid. Local pipes won't have
anything near that pressure - presumably there's a regulator where the
offtake plugs into the main grid.

The other method of storage was LNG - but apparently it took a week to
liquify a days worth of gas (or something like that). However there was
an LNG port on Canvey Island where imported gas (in those days from
Algeria) could be bought into the grid. There may have been another near
Liverpool ... BICBW. However I know the Canvey site got sold off.

There is a massive gas store at Milford Haven.
http://en.wikipedia.org/wiki/Dragon_LNG_terminal#LNG