Generator Size Checks

Will a 5000 watt generator run window AC, refrigerator, and router?

Use the default WattSizer rule: add running watts, then model the largest startup load while the other selected loads are already running.

Running watts1,305 W
Starting watts3,005 W
Recommended size3,700 W

A 5,000 W unit clears this estimate, subject to nameplate checks.

The peak-starting assumption is driven by 10,000 BTU window AC. With the default 20% buffer, WattSizer rounds up to the next 100 watts.

ApplianceRunningStartingSource note
10,000 BTU window AC1,100 W2,800 WRoom AC nameplates vary by efficiency and compressor type; default is a planning value for larger 115 V units.
Refrigerator180 W1,200 WDOE appliance-use guidance says sample wattages vary by age and features; default is a conservative planning value for a modern full-size refrigerator.
Router and modem25 W25 WHome electronics wattage varies by device; DOE advises measuring or checking adapters for accurate values.

Try the load yourself

Edit this scenario

Running load0 W
Starting load0 W

Recommended generator0 W
LoadRunning wattsStarting watts

Power station estimate

For battery units, the selected running load needs about 0 Wh for 8 hours or 0 Wh for 12 hours before weather, battery age, and inverter losses.

Safety check

Never operate a fuel-burning generator indoors, in a garage, on a porch, or near open windows. Use a listed transfer switch or interlock installed by a qualified electrician for home wiring, and verify actual device nameplates before buying equipment.

Generator or power station?

Fuel generators are useful for motor loads and longer outages, while battery power stations are better for indoor-safe electronics and medical-device planning. For battery sizing, this selected running load is about 12,550 Wh for 8 hours with the same buffer.

Never operate a fuel-burning generator indoors, in a garage, on a porch, or near open windows. Use a listed transfer switch or interlock installed by a qualified electrician for home wiring, and verify actual device nameplates before buying equipment.