You set up backup power at home with one of five solutions: a portable power station (battery), a fuel-powered generator, a home battery with island mode, solar panels with a hybrid inverter, or a UPS for your most critical devices. For most households a power station of 300 to 1,500 euros is the simplest, safest choice: it works straight out of the box, it is quiet, and it needs no dangerous wiring.
If you want to bridge your whole house or fixed circuits automatically, you end up at a home battery or a generator with a proper transfer switch. And that last part is exactly where it can turn deadly if you get it wrong. Backfeeding a generator “just for a moment” through a socket can cost a lineman on the other side of the street their life.
In this guide I lay out every option honestly, side by side. What does it cost, how much power do you get, how long does it bridge an outage, and who is it worth it for. After that I work out with you how much power you really need (this is where most people get it wrong), and I explain how to wire it safely. At the end you will find a decision tree that leads you to the right choice in two minutes.
What are the options for backup power at home?
There are five routes. They differ enormously in price, in how much they can handle, and in how much hassle they cause. A quick look at all five, then we go deep.
1. Power station (battery generator). A large battery with sockets on it. Portable, quiet, ready to go. You plug appliances straight into it. No installation, no fuel, no exhaust fumes. Perfect for the fridge, router and phone.
2. Generator (petrol, diesel or gas). An engine that turns fuel into electricity. Delivers plenty of power, even for heavy appliances, and runs for days as long as you keep adding fuel. But: noise, exhaust fumes (CO), and it has to stand outside.
3. Home battery with backup function. A permanently installed battery in your consumer unit, usually paired with solar panels. With the right function it switches over automatically during an outage. Quiet and low-maintenance, but expensive, and not every battery can do it.
4. Solar panels with a hybrid inverter. Your solar panels that keep working during an outage, combined with a battery. During the day you recharge on sunlight, which lets you bridge an outage much longer. Not a standalone solution, but an extension of option 3.
5. UPS (backup battery for critical devices). A small box that takes over within milliseconds so your PC, modem or medical equipment never goes down. It only bridges short outages (minutes to half an hour), nothing more.
Important to understand: these options do not rule each other out. Many people combine a UPS for the router with a power station for the fridge. And a home battery is mainly interesting if you are already considering one for your electricity bill anyway.
Comparison table: all backup power options at a glance
Here you can see at a glance what each option costs, handles and delivers. Prices include VAT and are based on the market in 2026.
| Option | Cost | Power | Bridges | Installation | Who it is for |
|---|---|---|---|---|---|
| UPS | 50 to 300 euros | 300 to 1,500 W | 5 to 30 min | Plug in | PC, modem, alarm, medical |
| Power station | 300 to 1,500 euros | 600 to 3,600 W | 3 to 12 hours | None | Fridge, lighting, router, phone |
| Generator | 300 to 2,000 euros | 2,000 to 6,500 W | Days (with fuel) | Outside + transfer switch | Long outages, heavy appliances |
| Home battery with backup | 5,000 to 15,000 euros | 3,000 to 5,000 W | Half a day to 2 days | Qualified installer | Fixed circuits, automatic |
| Solar panels + hybrid inverter | Extra 1,000 to 3,000 euros | Depends on the battery | Unlimited in sunlight | Qualified installer | Off-grid feel, long outages |
What jumps out straight away: there is an enormous gap between the first two options (a few hundred euros, usable right away) and the last three (thousands of euros, an installer needed). That gap decides the choice for a lot of people. If you just want peace of mind during an outage of a few hours, a power station is the logical step. If you want to make your house truly resilient against longer outages, it becomes more serious work.
Option 1: a power station as backup power during a power cut
A power station is the best starting solution for nine out of ten households. It is essentially a hefty battery with an inverter, fitted with sockets, USB ports and sometimes a car outlet.
You take it out of the box, charge it, and put it in the cupboard until you need it. During an outage you plug your fridge, a lamp and your router straight into it. Done. No consumer unit, no installer, no risk.
What does it cost? Reckon on 300 euros for a small model of around 500 Wh, up to 1,500 euros for a sturdy one of 2,000 to 3,000 Wh. For most people a model of 1,000 to 2,000 Wh (around 800 to 1,200 euros) is the sweet spot.
How much power and how long? Watch two numbers: the capacity in watt-hours (Wh, how long) and the output power in watts (W, how heavy). A power station of 1,000 Wh with 1,500 W output feeds a 150 W fridge for roughly 6 to 10 hours, or keeps your router, phones and a few lamps running for half a day.
Who is it for? Renters, people without solar panels, and anyone who mainly wants peace of mind during short outages without any hassle. Also ideal if you live in an area where the power drops out for a few hours now and then.
Pros: quiet, safe to use indoors (no exhaust fumes), ready to go, no installation, movable (also handy for camping).
Cons: limited capacity. During an outage lasting several days you will run the battery flat, unless you top it up with a solar panel during the day. And it will not handle heavy appliances (oven, washing machine, heat pump).
Option 2: a generator for long or heavy backup power
A generator is the classic backup power source: a petrol, diesel or gas engine that drives an alternator. As long as you have fuel, you have electricity. That makes it unique for long outages.
What does it cost? A simple petrol generator starts at around 300 euros. A quiet inverter generator (which delivers clean, appliance-friendly power) costs 600 to 1,200 euros. Heavier whole-house models (6,500 W) run towards 1,500 to 2,000 euros.
How much power and how long? Models range from 2,000 W (basics: fridge, lighting, heating pump) to 6,500 W (heavier appliances). Consumption depends heavily on the load: a small generator of 2,000 to 2,500 W burns roughly 1 to 1.5 litres of petrol per hour at full power, and clearly less under a light load. So with a tank of 4 to 6 litres a model like that runs roughly 3 to 5 hours at full power, and longer under a lighter load; after that you have to refuel. Heavier models use proportionally more. Diesel is more economical, and propane/gas is cleaner and easier to store.
Important: choose an inverter generator if you are feeding sensitive electronics. A cheap generator delivers “dirty” power with fluctuating voltage and frequency, which modern appliances (and certainly a boiler with a circuit board) cannot handle.
Who is it for? People who want to guard against long outages lasting days, or who have to run heavy appliances. Think rural areas, a business at home, or anyone who really cannot do without.
Pros: plenty of power per euro, practically unlimited run time as long as you have fuel, suitable for heavy appliances.
Cons: noise (60 to 70 dB, only tolerable at a distance), exhaust fumes, fuel storage, maintenance, and the deadly pitfall below.
CO is a killer. A petrol or diesel generator produces carbon monoxide: colourless, odourless and deadly. NEVER run a generator in an enclosed space. Not in the garage, not in the shed, not in the cellar, not even with a window open. It belongs outside, at least five metres from windows, doors and air vents. Every year people die from a generator that was standing inside “just for a bit”.
Option 3: a home battery with backup function
A home battery is a permanently installed battery, usually paired with your solar panels. With the right backup function (island mode) it automatically takes over the supply of selected circuits in your consumer unit during an outage.
This is the most comfortable solution: you barely notice the outage, everything happens by itself, and there is no noise or fuel. But it is also the most expensive, and not every battery can do it.
Watch out for this pitfall. An ordinary home battery delivers NO backup power during a grid outage. In fact, it actually shuts itself down. This is called anti-islanding and it is a safety requirement of the grid. Only a battery equipped for island mode, with the right switching, keeps running when the grid drops out. Ask about this explicitly, because the brochure often keeps quiet about it.
What does it cost? A complete system with a backup function costs 5,000 to 15,000 euros including installation, depending on capacity and brand. A 10 kWh battery bridges half a day to two days depending on your consumption.
Who is it for? Mainly interesting if you are already considering a home battery for your electricity bill anyway, and you take the backup function along as a bonus. Purely for backup power it is rarely the cheapest choice.
I am not going deep here on capacity, payback time and which brands support island mode, because I have a separate article about that. For this buying guide the most important thing is this: if backup power is your only goal, look at a power station or a generator first. The home battery only pays off if you also use it daily to bring down your electricity bill.
Option 4: solar panels with a hybrid inverter
This is not a standalone solution, but a powerful extension of the home battery. A hybrid inverter can keep your solar panels working during an outage too, so you recharge your battery on sunlight during the day.
The effect: where an ordinary battery is empty after half a day, with sun on board you can in principle bridge indefinitely, as long as the sun shines. This is the closest thing to off-grid backup power that most households can realistically get.
What does it cost? The extra cost of a hybrid inverter with a backup function compared to an ordinary setup is roughly 1,000 to 3,000 euros, on top of your battery and panel costs.
Who is it for? People who already have (or are considering) solar panels and a battery, and who want maximum resilience against long outages. In summer you then practically have a self-sufficient house during an outage.
Note: island mode and anti-islanding apply here too. This has to be installed correctly, otherwise your panels and battery will simply shut down during an outage. A qualified installer is not a luxury here but a necessity.
Option 5: a UPS for critical devices
A UPS (uninterruptible power supply) is a small box that takes over within milliseconds when the power drops out. So fast that your device does not even notice.
It is not meant to run your house, but to stop sensitive equipment from going down or losing data in the seconds before you connect another backup source.
What does it cost? 50 to 300 euros, depending on power and run time.
Bridges: usually 5 to 30 minutes. Enough to shut your PC down cleanly, or to bridge the gap until your generator is running.
Who is it for? Anyone with a home workspace, a NAS, an alarm system or medical equipment that cannot tolerate a single second of outage. Often as a supplement to one of the other options.
How much power do I need for backup power?
This is where most people misjudge it, and it is the most important calculation in this whole guide. You need two numbers: continuous power and starting power.
Continuous power (watts) is what an appliance draws while it is running. Starting power (peak) is the big gulp of electricity that motors and compressors briefly need when they switch on. A fridge draws two to three times its normal consumption when it starts up. If you pick a backup source on continuous power alone, it will cut out the moment the fridge kicks in.
Here are realistic wattages for common appliances:
| Appliance | Continuous power | Starting power (peak) |
|---|---|---|
| LED lamps (each) | 5 to 10 W | 5 to 10 W |
| Router and modem | 20 to 60 W | 20 to 60 W |
| Charging a laptop | 40 to 90 W | 40 to 90 W |
| Boiler + pump | 100 to 150 W | 300 to 500 W |
| Fridge | 150 to 300 W | 400 to 900 W |
| Freezer | 150 to 350 W | 400 to 1,000 W |
| Kettle or microwave | 800 to 1,500 W | 800 to 1,500 W |
| Washing machine | 500 to 2,200 W | 1,500 to 3,000 W |
Worked example. Say you want to run your fridge, your boiler, your router and three lamps during an outage.
Continuous: 250 (fridge) + 130 (boiler) + 40 (router) + 25 (three lamps) = 445 watts.
Now the starting power. The fridge peaks to around 700 watts on start-up, and the boiler pump to around 400 watts. Those two can start at the same time. So reckon on a backup source that can handle around 1,500 watts briefly, and delivers 500 to 800 watts continuously.
See it? Based on continuous power (445 W) you would pick a small unit. But because of the start-up peaks you actually need at least 1,500 watts of peak power in practice. That is the mistake people make: they buy a power station or generator that is too light, and it cuts out the moment the fridge kicks in.
Rule of thumb: add up your continuous power, add the largest start-up peak of your heaviest appliance, and pick a backup source with a bit of margin above that. Want to run the kettle, oven or washing machine too? Then you are quickly at 3,000 watts or more, and you end up at a generator or a large home battery. A power station usually cannot handle that.
Whole house or just critical circuits?
Before you choose a solution, you decide something important: do you want to bridge your whole house, or just a few critical circuits?
Critical circuits (recommended). You feed only the things that really matter: fridge, freezer, boiler, some lighting, and your router. That is usually 500 to 1,500 watts. This way you can get by with a much smaller, cheaper backup source, and you keep it manageable. For a home battery or generator, an installer wires up one or two separate backup circuits for this.
Whole house. You want to be able to use everything, including heavy appliances. Then you need a hefty generator (5,000 to 6,500 watts) or a large battery system, plus a transfer switch that can take over your entire installation. More expensive and more complex.
For most households “critical circuits” is the smart answer. During an outage you do not need a washing machine or an oven. You want your food to stay cold, your house warm, and yourself reachable. That takes surprisingly little power.
How do you wire backup power safely? (Read this)
This is the part that is about life and death, so read it carefully. A power station and a UPS are safe: you plug appliances straight into them, done. The danger lies with a generator or battery that you want to connect to your house installation.
Never “backfeed” through a socket. The biggest and deadliest mistake is plugging a generator into a socket with a double-ended lead to feed your house. This is called backfeed, and it is deadly. You then also put voltage onto the public grid. A lineman working further along on what he believes is a “dead” cable can die because of it. On top of that, it wrecks your appliances the moment the grid comes back and your generator runs against it. Never do this. Really never.
You need a transfer switch. To put a generator or battery on your installation safely, your house first has to be guaranteed disconnected from the grid. That is what a transfer switch is for. It makes sure that grid power and your backup source can never be active at the same time.
A manual transfer switch (for example a 4-pole type like the Hager SFT440) has three positions:
- Position I (grid): normal supply from the grid.
- Position 0 (off): everything disconnected, the safe in-between step.
- Position II (backup supply): your generator or battery.
During an outage you switch to 0, connect your backup source, and turn to II. When the grid comes back, you do it the other way round. Why 4-pole? Because you switch both the live conductors and the neutral in a controlled way, which prevents unsafe couplings.
Automatic or manual. A manual transfer switch is cheaper (the switch itself costs a few hundred euros) but you have to be there yourself. An automatic transfer switch (ATS) switches over by itself within seconds, and is often built into home batteries with island mode. More convenient, but more expensive.
Earthing and the neutral point. With a generator the neutral point has to be earthed correctly (the neutral bonded to earth), otherwise you get a “floating supply” that is dangerous and stops your RCD from tripping. This is not a DIY job.
Always have the fixed connection done by a qualified electrician. A transfer switch or backup power installation in your consumer unit falls under the wiring regulations and must be carried out by a qualified electrician. This is not the moment to save money or improvise. A wrongly connected generator is deadly for you AND for the people working on the grid. Reckon on several hundred to well over a thousand euros for a proper transfer switch installation, depending on your consumer unit and whether it is manual or automatic.
Decision tree: which backup power solution suits you?
Run through these questions and you will know within two minutes which way to go.
1. Do you just want to bridge a short outage of a few hours, without any hassle?
Yes: get a power station of 1,000 to 2,000 Wh (800 to 1,200 euros). Done. Safe, quiet, no installation.
2. Do you only have critical electronics that must never go down for a second (PC, NAS, medical)?
Yes: a UPS (50 to 300 euros), possibly alongside a power station for the rest.
3. Do you want to guard against long outages lasting days, or run heavy appliances?
Yes: an inverter generator (2,500 to 6,500 W, 600 to 2,000 euros), used outside, with a transfer switch fitted by a qualified electrician.
4. Are you already considering a home battery for your electricity bill anyway?
Yes: then choose a model with island mode and take the backup function along. Purely for backup power a battery is rarely the cheapest choice.
5. Do you have solar panels and want maximum self-sufficiency during long outages?
Yes: a hybrid inverter with a backup function on top of your battery, so you recharge on sunlight during the day.
The common thread: start small and safe. For the vast majority of households a power station of around 1,000 euros covers 90 percent of the outages you actually experience in practice, with no installer and no risk. Go heavier, and that is when the transfer switch and the qualified electrician come into play.
Frequently asked questions
Can I just plug a generator into a socket to feed my house?
No, absolutely not. That is called backfeed and it is deadly. You then put voltage onto the public grid, which means a lineman working further along on the cable can die. You always need a transfer switch that disconnects your house from the grid first, fitted by a qualified electrician.
What is the cheapest way to set up backup power at home?
For short outages a power station from around 300 euros is the cheapest safe solution. If you want more power for longer, a simple generator from 300 euros is cheaper in power per euro, but then you also add the cost of a transfer switch and an electrician.
How many watts do I need to run my fridge and boiler on backup power?
Around 400 to 500 watts continuously, but your backup source has to handle at least 1,500 watts of peak because of the starting power. A fridge draws two to three times its normal consumption when it starts up. Always reckon on the start-up peak, not just the continuous power, otherwise your backup source will cut out.
Does my home battery work automatically as backup power during a power cut?
Not automatically. An ordinary home battery actually shuts itself down during a grid outage (anti-islanding, a safety requirement of the grid). Only a battery equipped for island mode, with the right switching, delivers backup power. Ask about this explicitly when you buy.
Am I allowed to run a generator in my garage or shed?
No. A petrol or diesel generator produces carbon monoxide: colourless, odourless and deadly. Always use it outside, at least five metres from windows, doors and air vents, and not even with a window open. A gas or propane model is cleaner, but it also belongs outside.
How long can I bridge an outage with a power station?
A power station of 1,000 Wh feeds a 150-watt fridge for roughly 6 to 10 hours, or keeps your router, phones and some lighting running for half a day. If you want to bridge several days, you recharge it with a solar panel during the day, or you choose a generator.
Backup power is one part of a house you have well in hand. But the biggest gain usually is not in what you buy for when the power goes out, it is in what you pay every day when the power is simply there. Insulation, heating smartly, and waste you do not even see.
I have put everything I know about bringing down your electricity bill together in the guide on the Energy Crusher. Concrete steps and honest figures, no sales pitch. Have a look around: energy-crusher.fredsdiyplans.com