Power station or generator?
Start with the jobs you need powered, their running and starting demand, and a safe connection. A power station has finite stored energy. A generator needs safe outdoor siting, fuel and maintenance.
Use your home plan
How long would a power station last?
Tick what you want to keep running. We use typical figures, so you do not need to look anything up. If you know the real wattage from a label, change it.
Tick at least one item to see an estimate.
Typical sizes: small about 250 Wh, medium about 1000 Wh, large about 2000 Wh. We use the cautious end of current figures: a quarter of the stored energy is allowed for losses, plus the power station's own draw, and a full charge is assumed. Only one motor, such as a fridge, is allowed to start at a time. A fridge uses less than its running figure because its motor switches on and off. Hard-wired items such as pumps need an electrician to fit a plug or changeover first, so they are not counted.
I have my equipment's label figures
Check exact ratings
Use the figures printed on your power station and appliances. This is a planning estimate for non-medical loads.
The supply ratings
Check the label or ask the supplier. Missing ratings do not count as a capable supply.
Never use a generator, barbecue or outdoor heater indoors or in a garage. Carbon monoxide can kill. Use a registered electrician for any home changeover. Never backfeed through a socket.
For fixed house wiring, use a registered electrician and the proper changeover arrangement. Never feed a wall socket. A generator must stay outdoors, away from openings; carbon monoxide can kill.
EV backup limits · Installed battery and EPS
Source: ESB Networks standby generation, HSE carbon monoxide guidance. Checked 2026-10-28.