How Much Power Do You Need? Appliance Wattage Chart and Sizing Walkthrough
Most homeowners need between 1,500 and 7,500 watts to get through an outage, depending on what they run. The method is simple: list your must-have devices, add their running watts, then add the biggest startup surge on top.
Typical appliance wattage
These figures are approximate. Your own appliance's label or manual has the exact numbers, and the starting watts are the figures that catch people out.
| Appliance | Running watts | Starting watts |
|---|---|---|
| Phone charger | 5 to 20 | None |
| LED light bulb | 8 to 12 | None |
| Wi-Fi router | 10 to 20 | None |
| Laptop | 50 to 100 | None |
| LED TV (40 to 55 in) | 60 to 150 | None |
| Ceiling fan | 30 to 100 | Up to 2x running |
| Refrigerator | 100 to 200 | 600 to 1,200 |
| Chest freezer | 100 to 200 | 300 to 800 |
| Microwave | 600 to 1,500 | None |
| Coffee maker | 600 to 1,200 | None |
| Furnace fan (gas furnace) | 400 to 800 | 1,000 to 2,000 |
| Sump pump (1/3 hp) | 800 | 1,300 to 2,000 |
| Well pump (1/2 hp) | 1,000 | 2,100 or more |
| Portable space heater | 1,500 | None |
| Window AC (8,000 BTU) | 700 to 900 | 1,200 to 1,800 |
| Central AC (3 ton) | 3,500 | 6,000 to 10,000 |
| Electric water heater | 4,000 to 4,500 | None |
A worked example
Say you want to keep a refrigerator, gas furnace fan, a few lights, a router, a TV and phone chargers running.
- Running watts: fridge 150 + furnace fan 600 + lights 60 + router 15 + TV 100 + chargers 20 = 945 W
- Biggest surge: the furnace fan starts at about 1,200 W, which is 600 W above its running load
- Starting requirement: 945 + 600 = 1,545 W
- Add 20 percent headroom: about 1,135 running and 1,855 starting
A generator or power station in the 2,000-watt class covers this comfortably.
If you are shopping for a power station
Power stations add one more step: energy. Multiply your average watts by the hours you need. A refrigerator averages far less than its running watts because the compressor cycles on and off. A rough rule is that it runs about a third of the time, which is around 1,000 to 1,500 Wh per day.
Tips that shrink the number
- Run big loads one at a time instead of together
- Skip electric water heaters, electric ovens and central AC unless you buy a large unit
- Swap resistance heating for blankets and layers
- Use LED lighting
New to the terms? Start with watts explained, and see how to connect a generator to your home safely.
Browse Home Backup Power or Portable Power Stations.