A power station can make a short outage more comfortable, but the right capacity depends on what you need to run.
Separate power from energy
Watts describe how much power a device draws at a moment. Watt-hours describe roughly how much energy the battery holds. Add the watts of devices you plan to run simultaneously, then estimate their use over time. Allow for inverter losses and real-world battery limitations. For example, a phone, LED lamp and internet router generally create a much smaller load than space heating or cooking.
Prioritize safe everyday uses
Small units are often best for phones, lights and low-load electronics. Larger units can support more demanding appliances, but should still be checked against the appliance startup and operating requirements. Never improvise a connection between a portable station and your home's electrical wiring.
Read the safety details
Check manufacturer instructions on ventilation, ambient temperature, recharge cycles, charging accessories and indoor operation. Compare battery chemistry, warranty, serviceability and the outputs you genuinely need rather than buying on the biggest headline wattage.