Get matched with top generator install pros in Nokomis, IL

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.

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.

Generally, you’ll want to keep between 60 and 70 feet between the generator and the transfer switch. There are a few reasons for this, including:

• The distance reduces the noise coming from the generator into your home.

• It increases efficiency because you won’t have a voltage drop from this short of a distance.

• Prevents carbon monoxide poisoning: keep at least 15 feet between your generator and an open window. 

A 10,000-watt generator can run a small to mid-sized central AC unit (typically up to 3 tons or 36,000 BTU) along with a few other appliances. However, larger AC units or additional loads will require a bigger generator. Consult a local generator installer to ensure you add the correct size generator to your home.