Power station or gas generator?

What each one is

A portable generator is an engine turning an alternator. It runs outdoors only (its exhaust carries carbon monoxide, which kills people every storm season), it needs fuel stored and refreshed, it is loud, and it produces power continuously at its rating for as long as the tank lasts, typically 8 to 12 hours per tank at half load for the common 2,000 to 4,000 W inverter models.

A portable power station is a lithium battery with an inverter. It runs anywhere including a bedroom, it is silent, it needs no fuel, and it delivers a fixed store of energy: the largest current unit holds 6,438 Wh, after which it must be refilled from the wall, a car or a solar panel. Its running cost is close to zero; its purchase cost per stored watt-hour is the number to compare.

The outage kit: what a battery covers

The loads that matter in most outages are small. A full-size refrigerator averages 41 W over a day, a router 24 W, lights and phones a few watts each: the whole kit is about 1,645 Wh a day, 2,323 Wh after inverter losses and headroom. 16 of the 56 current units clear a day of it, the cheapest being OUPES Mega 3 at $1,099. For that job a power station wins on every count but one: it costs more up front than a small generator, and it cannot run for a week without sun.

Where the battery cannot follow

Heat and horsepower. A 1,500 W space heater empties even the largest current unit (6,438 Wh) in about 3.6 hours; central air, an electric range, a water heater, a well pump running all day and an electric dryer are generator jobs, or jobs for a wired home battery many times the size of anything portable. Power tools sit in between: a 1,800 W circular saw runs from any unit whose surge clears its start, but a day of it is a generator's day. The other limit is time without a refill: past three or four days with no sun, a generator with a can of fuel keeps going and a battery does not.

What each costs to run for a day

A generator burns roughly half a gallon to a gallon an hour at half load depending on its size, so a day of the outage kit costs a tank or two of fuel plus the engine's hours. A power station costs its purchase price divided by its cycles: a LiFePO4 unit stated for 3,000 cycles at $0.36 per Wh works out to a fraction of a cent per watt-hour delivered over its life, and the electricity to refill it costs cents. The generator wins on capital cost for high loads and long outages; the battery wins on running cost, noise, fumes and indoor use for the small loads that most outages are about.

Both, and a panel

Many households end up with a small power station for the bedroom and the medical device, and a generator or a solar panel to refill it. Every current unit charges from a wall outlet at its stated AC input, so a generator can top a battery up in an hour or two of running rather than all night, and a panel can do it silently: the solar generators pagelists the hours of sun each unit needs.