Portable Power Stations for Outages

A portable power station is a battery, an inverter, and a charge controller in a box with outlets on the front. You plug appliances into it. It never touches your house wiring, which is what makes it the simplest and safest form of backup power.

It is also the one most people should start with. It requires no permit, no electrician, and no decisions you cannot reverse.

What the two numbers mean

Every power station is sold on two figures, and they answer different questions.

Watt-hours (Wh) is capacity. How much energy it holds, and therefore how long it runs. This is the number that matters most for an outage.

Watts (W) is output. How much it can deliver at once, and therefore what you can plug into it. A unit might hold 1,000 Wh but only deliver 600 W, which means it can run a fridge but not a microwave.

Both constrain you, in different ways. Capacity too small means it runs out. Output too small means the appliance will not start at all.

There is usually a third figure, surge or peak watts, which is a brief overload rating for motor startup. A fridge compressor draws several times its running wattage for the fraction of a second it starts.

Sizing for what you actually need

Work out watt-hours per day for the things you genuinely need, not everything you own.

Load	Running watts	Realistic daily use
Modern fridge	100 to 200 W	1 to 2 kWh per day
LED lighting, several rooms	20 to 60 W	0.2 to 0.5 kWh
Wifi router and modem	10 to 20 W	0.3 kWh
Phone and laptop charging	30 to 100 W	0.2 to 0.5 kWh
CPAP without heated humidifier	30 to 60 W	0.3 kWh
Furnace blower (if on an outlet)	300 to 800 W	1 to 3 kWh

The fridge figure surprises people because a fridge does not run continuously. Its compressor cycles, typically a third to half the time. Check the yearly kWh figure on its energy label and divide by 365 for a better number than any estimate.

A household covering a fridge, lights, internet, and devices lands around 1.5 to 3 kWh per day. That is the realistic target for a full day of outage.

Subtract the inverter tax. Converting stored DC into AC loses roughly 10 to 15% as heat, so expect about 85% of rated capacity to reach your appliances. A 1,000 Wh unit delivers closer to 850 Wh.

What it will not run

This is the boundary of the whole approach, and it is worth being blunt about.

Anything hardwired. Furnaces, well pumps, sump pumps, central air, hardwired lighting. If there is no plug, a portable unit cannot power it without an electrician fitting a transfer switch, which is a different kind of installation.

Anything that makes heat. Space heaters, kettles, toasters, hair dryers, electric ranges, and coffee makers all draw 1,000 to 1,500 W continuously. Even where the inverter can supply it, a 1,000 Wh station running a 1,500 W heater lasts about half an hour. Resistive heating is the least efficient possible use of stored battery energy, and no portable unit is a realistic answer for heat.

Well pumps, which combine high running wattage with a very large startup surge.

A whole house. These units power appliances, not buildings.

Choosing one

Capacity for a realistic worst outage, not a comfortable one. Two days is a reasonable target for most places.

Continuous output covering everything on at once, plus surge headroom for the fridge starting.

LiFePO4 chemistry. Essentially all current stations use it, and it gives several thousand cycles rather than a few hundred. If you find one advertising a different lithium chemistry, it is either old stock or cutting corners.

Pure sine wave output. Standard on anything reputable now. Modified sine wave causes motors to run hot and upsets some electronics.

Solar input, if outages where you live can run past a day. Check the maximum input voltage before buying panels, because exceeding it damages the unit.

Enough of the right outlets, and note that USB-C ports fast enough to run a laptop are genuinely useful.

Fuel generators are a different proposition

Portable fuel generators are the traditional answer, and they solve a real problem: they run as long as you keep feeding them, which no battery does.

They also kill people every year, and the mechanism is carbon monoxide rather than electricity.

A generator never runs indoors. Not in a garage, even with the door open. Not in a basement, a shed, a breezeway, or a doorway. Outdoors, well away from windows, doors, and vents, and further away than feels necessary. CO is colourless and odorless, it accumulates, and the early symptoms resemble tiredness, which is why people fall asleep and do not wake up.

Fit working CO alarms on every level of the house before you ever run a generator, and test them.

Beyond CO: generators are loud, need fuel stored safely, need running periodically to stay reliable, and produce power that is often dirtier than a battery’s. Inverter generators are quieter and cleaner, and cost more.

For most households wanting a fridge and some lights through a storm, a battery station is quieter, safer, needs no fuel, and can live indoors. For multi-day rural outages in winter, a generator is often the honest answer, ideally through a properly installed transfer switch rather than a spider’s web of extension cords.

Practical use

• Charge it and keep it charged. A power station discovered flat during an outage is furniture. Top it up every few months.
• Run the fridge in cycles rather than continuously. A closed fridge holds temperature for hours, so powering it for twenty minutes an hour is often enough and stretches capacity substantially.
• Use decent extension cords, rated for the load and unrolled fully. A coiled cord under load gets hot.
• Keep it off the floor and dry, and out of direct sun.
• Watch the temperature. Lithium batteries do not like charging below freezing. In an unheated garage in winter, bring it inside to charge.

None of this requires a permit, an electrician, or a conversation with your utility. That is the point of this approach, and why it is the right starting place for most people.