Does a Personal Alarm Work in a Power Cut or Storm? A Guide for Ireland

In short: a personal alarm keeps working in a power cut for a while, not indefinitely. A home base unit runs on a backup battery whose life varies by model, an alarm that goes through the broadband router needs the router powered too, and anything that uses mobile signal needs the local mast to be working. In a big storm, all three can go at once. The answer is a plan made before the next red warning: charge, register, and agree who checks in.

Storm Éowyn, on 24 January 2025, showed how much a home depends on power. ESB Networks says 768,000 customers were without power at the peak, about a third of all properties, and the last were reconnected 18 days later. At the peak, about a third of mobile customers were affected too. Many families found out that week exactly how their loved one's alarm and phone connect. Here is what happens to each, and what to do before the next one.

The home alarm: a backup battery, for a time

A personal alarm's base unit plugs into the mains, and most have a backup battery that takes over when the power goes. How long it lasts depends on the model and the provider. TASK Community Care, for example, quotes up to 36 hours for its mobile SIM unit. Some other providers do not publish a figure at all.

How the unit connects matters just as much.

• A unit that plugs into the broadband router needs the router to stay powered as well, and a router has no battery of its own unless you add one.
• A unit with its own SIM needs the local mobile mast to be working.

Ask the provider three questions now, not during a storm: how long does the battery last, how does the unit show it is running on battery, and is the monitoring centre told when the power goes?

The home phone: fibre needs power

Most home phone services in Ireland now run over the internet. ComReg, the communications regulator, says that if the home loses power and the internet stops, the phone service and any devices that depend on the broadband connection will not work either. A battery backup for the router helps for a time, but only if the network itself still has power.

ComReg also says an alarm that used a landline might need to be replaced or reconfigured after a move to an internet phone service, and its guidance to phone companies treats customers with a monitored alarm as critical customers, who should not be switched off the old line until a working solution is in place. If your loved one's phone company is moving them, tell it about the alarm.

Mobile signal: masts need power too

A mobile phone or a watch with its own SIM does not care if the house has power, but it needs a working mast. After Storm Éowyn, Telecommunications Industry Ireland said plainly that masts stop working when they have no power, and an industry analysis put the battery backup at mobile sites at typically four to eight hours, where it exists. The government said about 35 per cent of mobile customers were affected at the peak. Even ESB Networks' own texts to vulnerable customers did not all get through, because of the loss of mobile coverage, and its volunteers made 17,000 phone calls instead.

Since then, a government group has been set up to improve telecoms resilience, and the operators have named priority sites outside the cities to keep a basic level of mobile voice coverage. ComReg is still honest about the limit: no form of communications technology is 100 per cent resilient. Calls to 112 or 999 can use any available network, even without credit.

A watch with its own SIM

A watch with its own SIM and battery keeps working through a power cut at home, as long as it is charged and the local mast is working. In a long outage, a charged power bank keeps it going. It cannot beat a mast that is down: if there is no mobile signal, no phone or watch can reach anyone. Our guide to mobile signal and alarm watches in Ireland explains how to check coverage where your loved one spends their time.

Registers worth joining

• ESB Networks vulnerable customer register. For people who rely on electrically powered medical equipment every day. You join through your electricity supplier. It brings advance notice of planned outages, text updates and a priority support line. ESB Networks says it does not mean the power is restored first.
• Your electricity supplier's register. The energy regulator, the CRU, says suppliers keep a register for customers who are vulnerable, including because of advanced age, which protects them from disconnection over the winter months. Joining is free.
• Gas Networks Ireland Special Services Register. It includes older customers, and brings priority reconnection and help with heating and cooking during a gas outage.
• Uisce Éireann's special services register. It includes customers aged 66 and over, and sends texts about water interruptions of more than four hours.

Before the next red warning: a checklist

• Get the warnings. Met Éireann sends county warnings through its app and by email, and Status Red warnings by text.
• Charge everything the day before: phones, the watch, and a power bank.
• Know the alarm's battery life, from the provider, before you need it.
• Keep the basics together: a torch with spare batteries, a battery or wind-up radio, and a written list of numbers, including the Eircode.
• Agree a check-in plan. Who rings, at what times, and who calls round in person if the phones are down. ESB Networks asks everyone to check in on older neighbours, family and friends before bad weather arrives.
• Save the numbers. ESB Networks faults: 1800 372 999. Emergencies: 112 or 999.
• Stay away from fallen wires. ESB Networks says never approach them, and report them on 1800 372 999.

During an outage, ESB Networks' PowerCheck website shows an estimated time for the power to come back. If the phones go down, the plan is a person: the neighbour or relative who calls round.

Where Norse fits

The Norse watch runs on its own battery with its own SIM, so a power cut at home does not stop it, and the family app tells you if the watch is about to run out of battery, so it gets charged before it goes quiet. But it depends on a working mobile mast, like any phone. In a storm that takes the masts down, it cannot reach anyone, and nothing else that uses mobile signal can either.

So the honest version is the same as for every device on this page: it is reassurance, not a guarantee. Keep the free Seniors Alert Scheme pendant for the house if your loved one qualifies, and make the check-in plan anyway. If you want cover for the hours they are out of the house, orders open in November, and you can see how the watch works on the watch page. If you are setting up a home alarm as well, our checklist for setting up a personal alarm at home goes through it step by step.