Guide · Before and after

The First Hour of a Power Cut — and the Hour After It Ends

Most of what determines how badly an outage goes is decided in the first sixty minutes, while the house is still warm and the phone is still charged. The hour after the power returns matters nearly as much, and almost nobody thinks about it at all.

Part one: the first hour

The first two minutes — is it only you?

Before anything else, establish the scale of it, because the answer changes everything you do next.

Look out of the window. Are the neighbours' lights on? Is the street lighting on? If your house is dark and the street is not, the problem is probably inside your own installation — check your consumer unit or breaker panel for a tripped switch, and if resetting it trips again, leave it off and call an electrician. If the whole street is dark, it is the network, and nothing in your house will fix it.

Report it, then find out how long

Utilities find out about outages partly from automated systems and partly from people ringing in. Reporting yours is not a formality: it helps them locate the fault, and it is how you get onto the list for updates.

Your supplier's outage page or app will usually give an estimated restoration time. That estimate is the single most useful piece of information you will get, because it decides whether this is an inconvenient evening or something that needs managing. Write the number down somewhere now, before you need it in the dark — and local radio is where the information appears when the network is also down.

If you are on a well, fill containers now

This is the most time-critical step in the whole article, and it closes within minutes.

If your water comes from a private well, the pump is electric and the only water you have is whatever is left in the pressure tank. Fill everything you can reach — jugs, pans, bottles, the kettle, and the bath if you have one, which gives you water for flushing. Once the pressure is gone, it is gone until the power is back.

On a municipal supply you usually keep pressure for a while, but filling a few containers early costs nothing and covers you if pumping stations are affected or a boil notice follows.

Leave the fridge and freezer shut

A closed refrigerator holds its temperature for a few hours; a full freezer holds considerably longer than a half-empty one. Every opening throws that away. Decide now what you will eat from the cupboard for the next day, take anything you need out of the fridge in one go, and then leave both doors alone.

If there is any chance of a long outage, this is also the moment to move the most valuable or most perishable items from the fridge into the freezer, where the surrounding frozen mass will protect them.

Light, before it gets dark

Find the torches while you can still see. A head torch per person is worth more than any number of hand torches, because the tasks ahead — cooking, carrying, finding things — need both hands. Set out what you will need before dusk rather than hunting for it afterwards.

Protect the phones

Mobile networks often keep running on their own batteries for a while, so your phone remains useful far longer than most things in the house — if it has charge. Drop the screen brightness, turn off anything that is not needed, and stop using it for entertainment. If you have a power bank, that is what it is for. A car can charge a phone too, but never run the engine in a closed garage.

Turn things off while you still remember

Before the house goes quiet, walk round and switch off at the wall anything that would come back on unattended: the oven, the hob, electric heaters, irons, electric blankets, the tumble dryer. When supply returns, often in the middle of the night, a forgotten appliance left switched on is a fire risk and an unnecessary surge.

Leave one light switched on. It is how you will know the power is back without getting up to check.

Check on people

A knock on a neighbour's door costs two minutes. Older people living alone, households with a new baby, anyone who depends on powered medical equipment or refrigerated medication — these are the people for whom an ordinary outage is not ordinary, and they are unlikely to ask.

Part two: the hour after it comes back

This is the half of the subject that almost never gets written about, and it is where the expensive mistakes happen.

Expect it to be unsteady

Supply often returns in stages, and the first minutes can include brief interruptions or voltage fluctuations as the network rebalances. Bringing everything back at once is hard on equipment and, across a whole street, hard on the network. Wait a few minutes, then switch things back on gradually, starting with what matters: the heating, the fridge, the water pump.

Sensitive electronics — computers, televisions, anything with a circuit board — are best left unplugged until supply has been steady for several minutes.

The food decision

This is where people lose money or make themselves ill, usually by trusting appearance rather than temperature.

• Judge by temperature and time, not by smell or looks. Food can be unsafe without any sign of it. If you have a thermometer, use it; an inexpensive fridge thermometer left in place answers this question definitively.
• Commonly cited guidance gives a refrigerator roughly four hours with the door kept closed, about a day for a half-full freezer and roughly twice that for a full one. These are rules of thumb, and they depend on the appliance and the room.
• Food still containing ice crystals can generally be refrozen, though the texture may suffer. Food that has fully thawed and been warm for an extended period should not be.
• When in doubt, throw it out. The cost of a replacement meal is not comparable to the cost of food poisoning in a household that has just had a difficult two days.
• Follow the guidance of your local food safety authority where it differs from anything here.

The water, if it was off

When a water supply is restored, the first water through the pipes can be discoloured or carry sediment stirred up by the pressure change. Run a cold tap for a while until it clears before drinking or cooking, and run it before using an appliance that draws water.

If a boil notice was issued for your area, it remains in force until your water utility says otherwise — not until the water looks clean, and not until the power comes back. Those are different things, and the notice is the one that counts.

Households on a well should let the pump restore pressure, then run taps until the water is clear. If there was any possibility of flooding or contamination around the wellhead, have the water tested before drinking it.

Put it all back

Reset the clocks and timers that matter — the heating programmer, the alarm clock, the oven timer that stops the oven working until it is set. Recharge the power bank, the torches and the phones now, while you still remember that you wished they were charged. Replace anything you used from the cupboard.

Write down what went wrong

This is the most valuable ten minutes in the whole event, and it has to happen within a day, while the irritation is fresh.

What did you not have? What could you not find in the dark? Which torch had dead batteries? Who did you wish you had phoned, and did you have the number written down anywhere other than a dying phone? Was the warm room the one you expected?

That list, written on the back of an envelope and stuck inside a cupboard door, is worth more than any article — including this one. It is specific to your house, and it is the difference between the next outage being a repeat and being easier.

The two lists

In short

In the first hour: find out whether it is only you, report it, get an estimate, fill water containers, leave the cold appliances shut, find the light, protect the phones, switch off what could restart unattended, and knock on the doors of people who might be struggling.

In the hour after: bring things back slowly, judge food by temperature rather than appearance, run the water until it is clear, and respect a boil notice until it is formally lifted. Then write down what you wished you had, before you forget.

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