Large electrical blow up in London, April 2015 news

[adam2]

Fire broke out over 24 hours ago in a cable tunnel in Kingsway, London, and is still burning.

Several thousand customers lacked power, people evacuated. Still ongoing with a gas main now damaged and the escaping gas burning at pavement level.

More details from the news site of your choice.

This is hardly TEOTWAWKI, but is does show the importance of both individuals and companies being prepared for this sort of thing.
I expect restoration of grid supplied electricity to take some weeks in the worst affected area, though supply should be restored to most within 24 hours by large generators instead of the grid supply.

Anecdotal reports suggest that very few standby generators worked, and that fewer still ran for more than a few hours.

SEE SIGLINE BELOW

[adam2]

Latest reports
http://www.bbc.co.uk/news/uk-england-london-32157618

[BritDownUnder]

Probably an old and/or overloaded cable that just gave up. For an interesting insight on what can happen to a city research the Auckland (New Zealand) power outage of 1998.

I am sure there are a lot more of these cables just waiting for their moment to fail.

[adam2]

Probably an old and/or overloaded cable that just gave up. For an interesting insight on what can happen to a city research the Auckland (New Zealand) power outage of 1998.

I am sure there are a lot more of these cables just waiting for their moment to fail.

Agree, though the load at the time of failure was not exceptional. In London the greatest risk of electrical infrastructure failure is during hot weather as the load is then greatest due to the air conditioning demand.

BTW, my sigline is a quote from the inquiry into the great Auckland power outage of 1998

[adam2]

Update after some years, here is a link that well describes the challenges in transporting and connecting sufficient large generators to the affected area.

https://www.mems.com/case-study/holborn-fire/

Note that the link is AN ADVERT for a generator hire company. But I feel justified in posting it out of general interest despite it being an advert.
I confirm that that I have no connection with the company featured.

[BritDownUnder]

Quite interesting advert that.

I recall being on a site that was stuffed full of generators of all sizes powering various parts of the site prior to commissioning. They were forever running out of fuel or, and I suspect sabotage by workers, rainwater was getting into opened door panels and tripping them.

There were so many Aggreko generators around I bought some shares in the damned company. They promptly tanked until they were taken over by an American investment fund recently and I sold making a 50 pound profit. No doubt the company will be asset stripped in due course and then sold off again.

I think it is appropriate to have standby generators around but they should be used sparingly. I hear there are 'generator farms' in the UK ready to provide power in times of need. I am not sure whether they get used much.

[adam2]

Indeed, Permanently installed diesel generators are a prudent precaution in large or complex buildings in case of a power cut. And are an essential precaution in hospitals and data centers.

Large transportable generators are most useful in case of large scale utility failures such as the Holborn one, and other similar events. Power can often be restored from large generators within a few hours, rather than the several days to replace whatever blew up.

And yes there are diesel generator farms connected into the grid. These are an expensive and un-green way of generating electricity but most useful in case of sudden shortages. They can start and run unattended and typically start automatically if the frequency drops below say 49.5 or 49.4 cycles. Can also be "told" to start by the duty engineer in the grid control room.
They serve a similar purpose to OCGT plant.

[kenneal - lagger]

There is a generator farm just to the north of Thatcham railway station in Berkshire, just down the road from me. I haven't seen it running recently although I haven't really looked but I have seen it running quite often in the past.

We had a generator at our local substation recently but I'm not sure whether it was powering the grid or the adjacent Thames Water water supply pumping station.