Output watts
AC output is the amount of power the station can deliver at once. If one appliance—or the combined load—exceeds that output, the station cannot reliably power the setup.
Surge power
Motors and compressors can briefly require considerably more power at startup than while running. Refrigerators, pumps and some tools are common examples. Check manufacturer labels or manuals for starting requirements and make sure the power station's surge capability can handle them.
Watt-hours and runtime
Battery capacity is usually expressed in watt-hours (Wh). A 1,000Wh battery does not mean every 1,000-watt load will run for exactly one hour because inverter losses, temperature and system overhead reduce usable runtime. Treat simple watt-hour math as an estimate, not a guarantee.
Choose around the job
For tailgating and device charging, portability may matter more than huge capacity. Camping adds lighting, fans, refrigeration and possibly cooking loads. Emergency backup may prioritize a refrigerator, communications equipment and selected essentials. High-draw electric heating and central HVAC can overwhelm smaller portable systems quickly.
Bottom line
Start with a load list, not a battery size. Determine simultaneous running watts, surge demand and desired runtime. Then choose a station with enough output and capacity plus useful headroom.