Get matched with top generator install pros in Mount Pleasant, WI

To determine the right size generator for your house, you should calculate the total wattage of the appliances and devices you want to power during an outage. List all essential items, note their start-up wattages, and add them together.

Here are some typical wattage requirements for common appliances:

• Refrigerator: 600 watts

• Large dehumidifier: 700 watts

• Large window air conditioner: 1,400 watts

• Water heater: 3,000 to 4,500 watts

• Electric furnace: 5,000 to 25,000 watts

A 7,500-watt generator might be sufficient for essentials like a refrigerator, freezer, well pump, and lighting circuits. However, for high-demand items like a water heater or furnace, a whole-home generator is a better choice. A portable generator may be enough if you only need to power a few critical items.

While home square footage can offer a rough estimate, it is not always a reliable indicator. For reference, here are some typical generator sizes based on square footage:

• 1,000 sq ft: 6–9 kW

• 1,500 sq ft: 7–10 kW

• 2,000 sq ft: 10–14 kW

• 2,500 sq ft: 12–16 kW

• 3,000 sq ft: 16–20 kW+

For the most accurate sizing, consult a professional who can calculate your home's peak and average power consumption and recommend the optimal generator.

Generators run on a variety of fuel types, ranging from natural gas to solar power. Keep in mind that fuel costs varying by type:

• Natural gas: $2,000–$21,000 per year 

• Liquid propane: $2,000–$21,000 per year

• Diesel: $3,000–$20,000 per year

• Gasoline: $500–$3,000 per year

• Solar generator: $2,000–$25,000 per unit

• Battery backup: $10,000–$25,000 per unit

If you’re wondering if you can use your electric vehicle as a backup battery, it depends on whether your EV is compatible with bidirectional charging. This technology allows energy to flow both ways, enabling vehicle-to-home (V2H) backup power, vehicle-to-load (V2L) for appliances and camping, and vehicle-to-grid (V2G) to support the power grid. Compatible EVs convert stored DC energy into usable AC power, helping reduce energy costs and enhance grid stability while providing emergency backup power.

While the rating will tell you how many watts the refrigerator needs at the peak of its cycle, it requires additional wattage to start. At the bare minimum, you’ll need a 1,500-watt generator to get the fridge up and running after a blackout. A 2,000-watt generator should be sufficient for most home refrigerators.