Long power outage, could it happen here ?

[adam2]

In urban areas of the UK power cuts are relativley rare, and supplies are usually restored in a few hours, especialy if a large area is affected.

Any long term power failure is usually considered only as part of a TEOTWAWKI situation.
However the central business district of Auckland, New Zealand suffered a near total loss of power for WEEKS.
And simply due to bad luck and breakdowns without any help from extreme weather or terrorists etc.

The report is interesting reading
http://www.skmconsulting.com/news/1998/ ... ailure.htm

I dont believe that this likely to happen here, but they probably thought that !

Failures of standby diesel generating plant were a great problem, I wonder how many standby generators in London could run for weeks at a time ? not very many I suspect.

A worrying number of people seem to believe that protection against power cuts may be obtained by having more than one electricity supplier.
These competing firms only retail power obtained in bulk from the same national grid, and distributed via the same cables.

Heat is the enemy of cables and transformers, a hot summer is forecast, air conditioning is getting cheaper and more widely used.

[emordnilap]

Heat is the enemy of cables and transformers, a hot summer is forecast, air conditioning is getting cheaper and more widely used.

Doesn't nuclear have a problem with hot summers too?

[adam2]

Heat is the enemy of cables and transformers, a hot summer is forecast, air conditioning is getting cheaper and more widely used.

Doesn't nuclear have a problem with hot summers too?

Sometimes yes, any steam power plant requires cooling water in order to condense the used steam and re-use it as boiler feed water.
In hot weather the water may be too warm for full load operation, also if river water is used for cooling, then in times of drought the water level may be too low for correct operation.
This is not restricted to nuclear plants but is a potential problem for any steam based power station, no matter if the steam is from fission, burning coal or solar thermal sources.

The problem in Auckland however was not lack of generating capacity, but was a series of cable failures and consequent inability to transmit enough power into the city center.

[biffvernon]

Failures of standby diesel generating plant were a great problem, I wonder how many standby generators in London could run for weeks at a time ? not very many I suspect.

That happened in the Canadian ice storm event a few years ago. Small diesel gennies just aren't built for continuous operation.

[adam2]

Small petrol driven generators are often only suited to very short term use.
Small diesels should be a bit more durable, as the engines are often based on small marine or car engines.

Large diesel engines SHOULD be able to run for weeks at a time since they are often based on ship or railway locomotive engines.
In practice though reliability is often very poor even with large continously rated engines.

In my experience the diesel engine seldom breaks unless grossly abused, the most common problems are

1) failure to start due to defective or discharged starter batteries.
2) runs out of fuel, the tank often being sized for only a few hours use, and not even kept full!
3) starts and runs for a while but stops due to overheating/lack of ventilation
4) coolant leaks out or was insufficient in the first place
5) starts and takes load briefly, but trips out on electrical overload
6) engine and alternator work fine, but no power supplied to the load due to defective changeover switchgear
7) runs out of lubricating oil, never a problem in a brief test, but after a few days ?

Another problem can be a standby generator that works perfectly, but only supplies essiential services, not every load.
The "elf an safety" then decide that the building is unsafe without every light working, and send everyone home!

[woodburner]

......... a hot summer is forecast, ...........

It had better hurry up then, it's only just over a week and the nights will start drawing in.

[kenneal - lagger]

......... a hot summer is forecast, ...........

It had better hurry up then, it's only just over a week and the nights will start drawing in.

Doomer!! ':evil:'

[woodburner]

......... a hot summer is forecast, ...........

It had better hurry up then, it's only just over a week and the nights will start drawing in.

Doomer!! ':evil:'

I refer you to http://www.powerswitch.org.uk/forum/vie ... eb265fdf8c

[adam2]

Not as bad as the great Auckland blackout, but an area in Sussex seems to have bad luck re electricity supply.
http://www.horstedkeynes.com/powercuts.html

Shows the wisdom of not being unduly reliant on grid power, and shows how useful batteries and generators can be.

For loads up to about 100 watts I would normally recomend battery backup, up to 3 hours back up is cheaply achieved, and up to about 24 hours is feasible though more costly.

For over about 400 watts, a generator is more likely to be suitable. Fuel storeage for 24 hours use is easy, and a week or two is possible.

Between 100 and 400 watts, generators and batteries both have their merits, and it comes down to personal preference, and to how long a failure one wishes to protect against.

For longer term failures, then battery back up is practical up to a week or even two weeks, provided that the average load is no more than about 20 watts. For greater loads it will normally be cheaper to charge the battery from a generator, from a vehicle, or from wind or PV, than to provide an even bigger battery