A power cut is rarely convenient. It can interrupt home working, leave a router and security camera offline, or turn a weekend away into a scramble for phone charge. This portable backup power buying guide helps you choose a power station for the devices you genuinely need, rather than paying for capacity or features that will sit unused.
Portable power stations are rechargeable battery units with AC sockets, USB ports and often 12V outputs. They are quieter, cleaner and easier to use indoors than fuel generators, making them a practical choice for short outages, camping, mobile work and off-grid monitoring. The right model depends on two separate questions: how much power your devices need at once, and how long you need them to run.
Start with the job your backup power must do
Before comparing battery sizes, decide what you are protecting. A small power station can keep essential low-power equipment going, while a larger unit can support heavier appliances for a limited period. Trying to buy one unit for every possible scenario often leads to overspending.
For many households, the priority during an outage is communication and visibility: a broadband router, mobile phones, a laptop and perhaps a security camera hub. At a rural property, it may be a 4G router, a camera system, a gate controller or a low-power monitoring device. For a caravan, campervan or shed, charging tools, lighting and a small fridge may matter more.
Write down each device, its wattage and the likely hours of use. The information is usually printed on the device, charger or power adaptor. If you only see volts and amps, multiply them to estimate watts. For example, a 12V device rated at 2A uses about 24W.
The figures can be surprisingly modest for connected devices. A router may use 10W to 20W, a laptop charger commonly 45W to 100W, and phones use little once charged. A kettle, hair dryer, fan heater or electric cooking appliance is very different: these can draw 1,000W to 3,000W or more. They need a high-output power station and will drain even a large battery quickly.
Portable backup power buying guide: watts and watt-hours
Two numbers decide whether a power station suits your needs. Watts, shown as W, describe the power it can supply at one time. Watt-hours, shown as Wh, describe the energy stored in the battery.
Think of watts as the width of a tap and watt-hours as the size of the tank. A 300W power station may have enough stored energy for a long evening of router, phone and laptop use, but it cannot run a 1,500W kettle because its inverter cannot provide the required output. Conversely, a unit with a high AC output but a small battery may run a demanding device, just not for very long.
For a rough runtime estimate, divide the battery capacity by the device wattage. A 500Wh station powering a 50W load looks like it should last ten hours. In real use, allow for conversion losses, temperature and the power station’s own consumption. Planning for around 80 to 85 per cent of the stated capacity is sensible when using AC sockets.
That means a 500Wh unit might provide around eight hours for a 50W device, or considerably longer for a router and a few phone chargers sharing a lower combined load. This is a guide, not a guarantee. A fridge cycles on and off, laptops vary their draw, and an older appliance can consume more than expected.
Match capacity to realistic use
A compact power station around 250Wh to 300Wh suits short trips, phones, tablets, lights and occasional laptop charging. It can also be useful for keeping a router running through a brief interruption, provided its output is sufficient.
Around 500Wh to 800Wh is often the practical middle ground for home backup and regular off-grid use. It gives more useful runtime for routers, laptops, camera equipment and small appliances without becoming too awkward to move.
Units of 1,000Wh and above are better for longer outages, mobile work setups, caravans, power tools or devices with greater demand. They bring more weight and cost, so they make most sense where the extra runtime solves a clear problem. If you need to support a household’s high-draw appliances for days, a portable power station may be part of the plan rather than the whole answer.
Check the outputs before capacity
A battery with plenty of watt-hours is no use if it cannot connect to your equipment. Check the type, number and rating of outputs you will use most often.
For mains-powered devices, look at the number of UK AC sockets and the continuous AC output rating. The continuous rating is the key figure for normal use. Some appliances also require a higher burst, or surge, of power to start, particularly compressors and certain tools. If a fridge needs a brief surge when its compressor starts, the station must be able to handle it even if the fridge’s normal running wattage is low.
USB-C Power Delivery is worth prioritising for newer phones, tablets and laptops. It can charge compatible devices directly and efficiently, avoiding the need to run a mains charger through the AC inverter. USB-A ports remain useful for smaller accessories, while a regulated 12V car socket can suit selected cool boxes, pumps and vehicle accessories.
For sensitive electronics, choose a model with a pure sine wave inverter. This provides mains-style power that is suitable for laptops, chargers, networking equipment and most household electronics. It is the sensible default for a backup unit intended to protect valuable devices.
Charging speed matters after the outage
A power station only helps if it can be recharged in a way that fits your routine. Mains charging is the simplest option, but recharge times vary widely. Faster charging is convenient when you have a narrow window between outages or want to pack for a trip at short notice. Slower charging may be perfectly acceptable for a station that normally stays topped up at home.
Solar charging adds independence for camping, remote sites and prolonged disruptions. Check the unit’s supported solar input, voltage range and maximum wattage. A large solar panel connected to a low-input station will not necessarily charge it faster than its limit allows. Weather, panel angle, shade and season also affect real-world solar performance, so treat quoted panel ratings as a best-case figure.
Car charging is handy while travelling, though it is usually slower than mains or solar. It is best seen as a useful extra rather than the main way to recharge a large battery.
Look for features that make backup genuinely useful
Battery chemistry affects long-term value. Lithium iron phosphate, often labelled LiFePO4, is popular because it generally offers a long cycle life and good thermal stability. It can cost more upfront, but is often a strong choice for a power station that will be charged and used regularly over several years.
An emergency power supply or UPS function can be valuable for a router, desktop computer or monitoring equipment. The station remains connected to the mains and switches to battery power when supply fails. Check the stated switchover time and compatibility with your device, as not every setup will tolerate even a brief interruption.
A clear screen is more useful than it sounds. Seeing input watts, output watts, remaining battery percentage and estimated runtime makes it much easier to manage power during an outage. An app can also be useful, especially where a station is stored in a garage, campervan or remote building, but it should not replace clear controls on the unit itself.
Do not overlook physical practicality. A 1,000Wh power station can be heavy, particularly if you need to carry it upstairs or load it into a car. Check dimensions, weight, handle design, cable storage and whether the unit can be safely positioned with ventilation around it.
Avoid the common buying mistakes
The most common error is buying by battery capacity alone. A large battery with only a modest AC output may not run the appliance you had in mind. The opposite mistake is choosing high wattage without enough watt-hours to provide meaningful runtime.
It is also worth avoiding permanent heavy loads. Portable stations are excellent for essentials, but electric heaters, kettles and cooking appliances consume energy at such a rate that they can empty a battery quickly. Use gas cooking, warm layers and low-power lighting where appropriate, and reserve the station for communication, safety and essential equipment.
Finally, plan the kit around the power station. Keep the right charging leads with it, test it before an outage, and recharge it after use. For home backup, a labelled box containing a router lead, USB-C cable, torch and power bank can make a difficult evening far more manageable.
The best portable power station is not necessarily the largest one. It is the one that keeps your most important devices working for the time you need, is simple to recharge, and is ready when the lights go out.
