Backup power for phones and optional electric heating
The calculator uses a transparent planning allowance of roughly 18Wh per basic full phone charge plus an efficiency margin. If your primary heating is electric, you can also enter its rated electrical input and planned hours/day to see how quickly stored energy is consumed.
Real device battery sizes, conversion losses, signal conditions and usage vary. For heating, energy capacity is only one constraint: confirm that any power station or backup source can safely supply the appliance’s continuous and start-up demand. Treat the result as an energy budget, not equipment approval.
Transparent assumptions
The methodology page lists the assumptions used, and country pages link to the official sources behind the public guidance. Where the site uses its own planning assumption rather than an official standard, it says so.
Build a device-by-device outage load
Instead of relying on a generic power-station size, the live planner lets you add the devices you actually expect to operate. For each load, enter a name, quantity, rated watts and expected hours per day. The calculator then combines those loads with the basic phone-energy allowance and any backup electric-heating plan.
Energy and power are different
Watt-hours describe an energy budget. They do not prove a battery or inverter can safely operate an appliance. Always check continuous output, start-up or surge requirements and the equipment manufacturer’s instructions before relying on a backup source.
Use limiting resilience
The tool converts the combined daily electrical demand into the number of days your stored energy can cover, capped at the selected planning horizon. This makes it easy to see whether power is the household’s actual limiting resource.
Why a device load planner is better than a generic battery size
Two households can both own a 1,000 Wh power station and have completely different resilience. One may only charge phones and run LED lighting; another may expect to operate refrigeration, networking equipment and electric heat. Home Resilience Check therefore asks for the loads rather than declaring a universal battery size.
Enter rated watts and realistic run time
Each additional load uses quantity × watts × hours per day × outage days. If a device cycles on and off, enter a planning run-time estimate that reflects how you intend to use it. The site does not populate appliance wattages because model-specific power consumption varies.
Heating is deliberately separated
Backup electric heating can dominate the entire energy budget, so it receives its own input and output rather than being hidden among small device loads. A 1,500 W heater used for several hours per day can require orders of magnitude more stored energy than phone charging.
Wh does not equal compatibility
Even when the energy budget is sufficient, the backup source must still support the appliance’s power draw, start-up behaviour and connection method. The result is therefore an energy-planning calculation rather than a product-safety approval.