Backup power for a flat
To keep the internet, lights and phones going for 8 hours without power, a 250 Wh station is enough. With the fridge you need 820 Wh. Answer a few questions and we will find you a specific model with its price.
What has to stay on?
Each option includes everything above it. Pick the one you really can't do without.
Answer a couple more questions and your options will appear here
Back to the questionsHow much capacity a flat needs
Station capacity for each set of appliances and each outage length. On the right, the start the station has to survive.
| What keeps running | 4 h | 8 h | 12 h | Start |
|---|---|---|---|---|
| Router, lights and phones | 170 Wh | 250 Wh | 310 Wh | 50 W |
| Router, lights, phones and fridge | 450 Wh | 820 Wh | 1,2 kWh | 1,2 kW |
| Router, lights, phones, fridge, laptop and TV | 1,3 kWh | 1,8 kWh | 2,2 kWh | 1,3 kW |
Each appliance is counted by how long it actually runs: the router all day, the lights for a few hours in the evening, the fridge about a third of the time. The figures already include about 37% of headroom for losses, partial discharge and battery ageing.
What to know about a power station for a flat
Why a flat usually gets a station
An inverter with batteries needs space on a wall or the floor and an electrician to connect it to the consumer unit. A flat rarely has a spare cupboard for it, or the appetite for new cabling. A power station simply stands in the room, and you plug your appliances into it.
The fridge decides which station you need
Without the fridge, a small 250 Wh station covers 8 hours. With it you need 820 Wh, and the station has to survive the compressor starting, about 1,2 kW: for a few seconds it draws several times what it does while running.
For a short outage you can leave the fridge off. Kept closed, it stays cold for about 4 hours, and the freezer for longer.
The kettle and an electric hob
A 2 kW kettle needs a station that delivers at least that much, and it eats the charge quickly: 5 minutes of boiling takes about 170 Wh. An electric hob at full power will flatten a small station in under an hour. If the building has no gas, a camping stove is the easier way to cook during outages.
Recharging between outages
When the power is cut on a schedule, the station has to recharge while it is on. Some stations charge from the mains in an hour or two, others take 6 to 8 hours. For outages that come one after another, that matters as much as capacity.
Safety and where it goes
- Choose a station with LiFePO4 (lithium iron phosphate) batteries. They are safer and last thousands of charge cycles.
- A 1 kWh station weighs about 10 to 13 kg, a 2 kWh one roughly twice that. Decide in advance where it will stand.
- The station's fan is audible while it charges, so the bedroom is not the best place for it.
- A solar panel on the balcony adds energy in summer, but in winter, when outages are most frequent, it gives little.
If your flat has its own gas boiler, read about backup power for a gas boiler too: it needs a pure sine wave and earthing, and more capacity than you might expect.
Common questions about a station for a flat
What station do I need to keep the router on?
A router draws about 10 to 15 W, so even a small station will do. Together with the lights and phone charging, 8 hours takes about 250 Wh.
Can a station run a fridge?
Yes, if it survives the compressor starting, about 1,2 kW, and has enough capacity. Together with the internet and lights, 8 hours takes 820 Wh. On average a fridge draws several times less than its sticker says, because the compressor does not run all the time.
Do I need an electrician?
No. The station charges from an ordinary socket and your appliances plug into the station. You only need an electrician if you want the station to power the flat's wiring rather than individual appliances.
How much does a station for a flat cost?
A small station for the internet and lights is inexpensive, and with the fridge the price grows with the capacity. The quiz above shows specific models with current prices, and it already knows you are in a flat.