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Problems in Power Cuts
Hidden things that fail in a power outage with consequences you should know about in advance!


When the electricity fails, the lights go out. Everyone knows that. But there are other things which you might not have thought about, and some of these can be awkward or even dangerous. Here's some advice which could help you in a power cut, worth reading now while your computer is still powered up, so, when there's an outage, you are forewarned!

When the power goes, there's initially maybe even some kind of romantic feel to it. You light some candles and have a candlelit dinner cooked on the gas. Almost an air of adventure to it. The first "unexpected" problem might be encountered when you want to warm a snack and you casually reach for the microwave oven, but oh, that's electric! It is these hidden problems which I'm going to explain more about, as some of them are somewhat more serious than the darkened microwave oven.

How about the doorbell? That's probably electric, powered off the mains with no battery backup. Burglar alarms have battery backup for obvious reasons, but doorbells often don't.

The fridge and contents will survive, especially if you keep the door closed most of the time. Just don't expect the light to come on when you open the door. A chest freezer is usually ok for a day or so. Power outages are rare in most places and don't last more than a few hours, but if you think the electricity is going to be off for more than four hours, it's best to put insulation around the freezer.

It might be easy to assume that the gas will be unaffected in an electric power cut, but this often isn't so! On a gas cooker, the oven light isn't a gaslight, and the ignition might be mains electric rather than piezoelectric. Do you have a box of matches? If so, you're still cooking with gas, but what about the gas central heating? Curious as it may seem, gas central heating boilers often have at their heart a weakness, as the circulator pump is mains AC electric. This whole subject of the problems of gas appliances in electricity failure gets a page to itself!

Even more serious than the misbehaviour of the gas system, is what happens to the phone if the electricity supply fails. It's easy to fall for the assumption that it will be unaffected, and this has an interesting history to it. In the old days, all the telephones in the area were powered from the telephone exchange, where there were huge banks of giant lead-acid batteries, and a well-maintained backup generator. So, you could still make phone calls during a power cut. These days it's not so simple, because some phones are fancy electronic gadgets and some of them require mains power to work at all. Cordless phones are vulnerable, as are VoIP and phones connected through a DSL box. For this reason, you should have at least one basic phone which is still works with no mains. Pick up a basic phone from somewhere, and if you think it looks untidy, keep it in the drawer with the candles!

Phones and their vulnerability to power failure are a subject which has a lot more to be said about it, so it gets a page telling a lot more about it. See phone problems in power cuts (the need to make an emergency call is higher during a power cut!)

In some areas, if the electricity fails, the domestic water supply also fails within a few minutes, leaving people with their only fresh tap water being from the toilet cistern tank and the immersion heater header tank. Most areas don't have this problem.

Other things:

Clocks. The misbehaviour of clocks during mains failure is different according to the type of technology used. Generally, clock radios, microwave oven clocks, and video recorder timers, all fail completely and forget what time it is. So, when the power comes back on, you'll have to reset them all. Mains powered mechanical clocks, for example on a Goblin Teasmade and on traditional electric cookers, can only run when the electricity is on but don't rely on electricity to remember their time setting, so they stop when the power fails, and then continue where they left off when it resumes. This means that after the power comes back on, they are now slow by however long the power was off. This is interesting to note, as you can tell how long the power outage lasted, but there is a more financial aspect which is that you should check your immersion heater timer and other time switches to see if they are continuing to operate at the correct (most economical) time. Battery powered clocks, and the type that you wind up with a key or balance weights, are unaffected.

Computers and a few other devices, do not shut down cleanly during a loss of power. In addition to losing data that was in use at the time of the failure, they can also have problems in restarting. Having an Uninterruptible Power Supply is a good idea. Some places where you can get a computer also sell these. Other devices which do not resume where they left off include air conditioning, video recorders, TV (goes into standby mode), photocopier, etc.

Radio. Never mind the TV. You need at least one radio which doesn't depend on mains electricity. It's a classic survival requirement, in case there is a real emergency.

Mobile phone. Obviously not requiring a mains lead all the time or it wouldn't be mobile, but do you keep it charged up? Hurricane preparedness sites recommend having a spare battery as well as keeping the phone charged up.

Electric security gates and electric garage doors. Definitely a battery backup required and/or manual handle, or it could become inconvenient.

A few extra notes, just in case it's any help:

* It's particularly useful to have an Inverter. This converts 12 volts DC from a car battery into 240 volts AC or 110 volts AC, so you can have some backup power for using low power appliances during power cuts.

* There are more emergencies during power cuts because of the increased fire risk of candles, and from people having accidents because of unseen hazards in the dark. Also, some makeshift heating arrangements can cause problems.

* Although you can cope with problems in power cuts, (especially now you've read this stuff!), some people cope less well and may need checking up on and looking after.


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