Listed in the chart below are average running and starting wattages for a number of everyday appliances and equipment. From this table, select the most important items you want your power generator to support. After you have made your initial selection, add the individual starting wattages to determine the base electrical load. The total is the APPROXIMATE size of power generator required. We can review it to verify its accuracy. Once the final size is known, you may wish to add other non-critical items to the list to ensure uninterrupted service.

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Typical Wattage Values for Residential and Small Commercial Appliances

Appliance Running Wattage Starting Wattage
Automatic Washer 1,200W 4,800W
Central Air Conditioner
1 Ton (12,000 Btu) 1,700W 4,000W
2 Ton (24,000 Btu) 3,200W 7,500W
3 Ton (36,000 Btu) 4,800W 11,600W
Clothes Dryer
Natural Gas 500W 1,8500W
Electric 5,500W 6,850W
Coffee Maker 1,200W 1,200W
Color TV – 27” 300W 300W
Dishwasher 1,500W 2,750W
Electric Skillet 1,250W 1,250W
Freezer 500W 2,500W
Furnace Fan (1/3 hp) 350W 2,3800W
Garage Door Opener (1/2 hp) 500W 3,600W
Hair Dryer 1,500W 1,500W
Iron 1,200W 1,200W
Microwave Oven 1,500W 2,250W
Personal Computer (only) 600W 600W
Radio (Portable) 100W 100W
Refrigerator 500W 2,500W
Space Heater 1,500W 1,500W
Sump Pump (1/4 hp) 250W 1,800W
Sump Pump (1/2 hp) 500W 3,600W
Toaster 1,250W 1,250W
Water Heater (electric) 4,500W
per element
per element
Well Pump (1/2 hp) 500W 3,600W
Toaster Oven 1,500W 1,500W
Emergency Lighting Sum of individual
lamp wattages
Sum of individual
lamp wattages
Your Total
1,000 Watts = 1 Kilowatt