Why this page exists
Many “best power station” lists repeat manufacturers’ spec sheets. That is not much use when the power goes off on a winter evening. Before we name any product, we want you to be able to see exactly how it will be judged. If a page on this site ever does not match this method, tell us and we will fix it.
What we will measure
| What | Why it matters in a power cut | How we will report it |
|---|---|---|
| Usable versus rated watt-hours | Converting battery power to mains (AC) loses energy, so you never get the full figure on the box. | Measured watt-hours delivered at a stated load |
| Continuous and surge watts | Fridges, pumps and some kitchen appliances draw a short spike when they start. | Manufacturer claim, plus whether our test loads started |
| UK 3-pin sockets | Some imported units have non-UK sockets. Adapters on high loads can be a fire risk. | Yes or no, and how many |
| Charge time | How quickly you can refill between cuts. | Measured from mains; solar only with the panel, date and weather stated |
| Pass-through | Whether devices stay on when the mains drops. | Observed: did our test devices stay on |
| Battery chemistry and cycle life | Affects weight and lifespan. | Manufacturer claim, clearly labelled as a claim |
| Weight and noise | Can you carry it upstairs? Is the fan loud in a bedroom? | Measured |
| Standby drain | A unit stored for months may be flat when you need it. | Charge lost after a stated storage period |
| App dependence | Phone signal and broadband may be down too. | Does everything work with no internet or account |
| Warranty and UK support | Who you call, and where it goes for repair. | Length, UK contact and returns |
Our test protocol
- Unbox and record sockets, cables, manuals and weight.
- Charge from mains to full, then rest.
- Discharge test at a constant, stated load until the unit cuts out. Record the watt-hours delivered. Repeat once and publish both runs.
- Mains charge time from empty to full.
- Surge check with a real appliance that has a motor or compressor.
- Switchover check: pull the mains plug with devices running through it, and record whether they stay on. We will not quote switchover times unless we have measured them with suitable equipment.
- Noise at a stated distance, idle and under load.
- Standby drain after storage switched off.
- No-internet check: can you see the charge level and switch outputs without the app?
We will publish the test equipment and room conditions with the first results. We have not chosen them yet.
Work out runtime yourself
Runtime (hours) ≈ usable watt-hours ÷ your device’s average watts
- Usable watt-hours are lower than the rated figure on the box, because some energy is lost converting to mains AC. Some manuals state an output or efficiency figure; use it if yours does. Until we have measured a unit, treat any answer as a best case.
- Your device’s watts: check the rating label or manual, or measure it with a plug-in energy meter. Appliances that cycle on and off, such as fridge-freezers, use different amounts at different times, and need a unit that can handle the start-up surge.
Example arithmetic, using made-up round numbers: a battery with 500 usable watt-hours running a device that draws 50 watts on average would last at most about 500 ÷ 50 = 10 hours. Cold rooms, older batteries and higher settings all cut that.
If you rely on powered medical equipment, ask your equipment provider what backup they recommend, and join the Priority Services Register. Ofgem says network operators must offer PSR customers extra help in power cuts, such as battery packs. We will never say a power station is suitable for a particular medical device. That is a question for your provider.
Power station or petrol generator?
| Question | Battery power station | Petrol generator |
|---|---|---|
| Indoors? | Yes, following the manufacturer’s instructions | Never. Not in a house, garage, shed, tent or caravan |
| Fumes | None | Exhaust contains carbon monoxide |
| Runtime | Limited by the battery | As long as there is fuel |
| Fuel at home | None | HSE says you can store up to 30 litres of petrol at home without telling your local Petroleum Enforcement Authority, in suitable containers. Larger amounts carry legal requirements. |
| Home wiring | Plug devices straight into it | Never plug into a socket or wire it in yourself. Only a qualified electrician should connect backup power to fixed wiring, using a changeover arrangement that keeps your home disconnected from the network. |
Never use a barbecue, camping stove, patio heater or generator indoors, or in a garage, tent, porch or caravan awning. They give off carbon monoxide (CO), a poisonous gas you cannot see, smell or taste. Fit an audible CO alarm marked EN 50291 (look for the BSI Kitemark) in rooms with fuel-burning appliances.
Headache, dizziness, feeling sick, tiredness, confusion and breathlessness can be signs of CO poisoning. Get into fresh air straight away. Call 999 if someone is seriously unwell, or NHS 111 for advice. If you suspect a leak, call the gas emergency number on 0800 111 999 (0800 002 001 in Northern Ireland). NHS advice on carbon monoxide.
Charging a lithium battery safely
Fire services give this advice for large lithium batteries such as e-bike batteries. It applies sensibly to power stations too:
- Use the manufacturer’s charger and cables.
- Charge while you are awake and at home, not overnight or while you are out.
- Do not charge or store it in a hallway or anywhere that blocks your way out.
- Do not cover it while charging, and unplug it when it is full.
- Stop using it if it is swollen, damaged, hot, hissing or smells unusual.
- Have working smoke alarms. If a battery catches fire, get out, stay out and call 999.
What we will not claim
- No star ratings, scores or “best overall” badges for anything we have not tested.
- No reviews or testimonials we did not collect.
- No cycle-life verification. We can only quote claims.
- No “powers your whole house” lines.
- No claims that a unit suits a specific medical device.
See how we label kit for what “Tested by us” and “Research-based” mean. We carry no affiliate links.
Kit for this guide
No products are listed on this page. When we test a power station, it will carry the “Tested by us” label with the date and results.
- Plug-in energy meter, for measuring your own devices Research-based
Official sources we used
- Buy safe, be safe: avoid e-bike and e-scooter fires (Office for Product Safety and Standards, GOV.UK)
- Lithium-ion batteries (Scottish Fire and Rescue Service)
- How to charge e-bikes and e-scooters safely (London Fire Brigade)
- Storing petrol at home and at clubs or associations (Health and Safety Executive)
- Carbon monoxide poisoning (NHS)
- Check if you can get a payment for a power cut (Ofgem)
- Priority Services Register (thepsr.co.uk)
- Report a power cut (Energy Networks Association (powercut105.com))