Get matched with top generator install pros in Gloster, MS

You can determine what size generator you need for a transfer switch by matching the switch to the largest outlet on your generator. Larger generators can power up to 10 circuits, while most 5,000-watt generators can provide power to six circuits. So, if your generator’s largest outlet is 30 amps, you’ll need a 30-amp transfer switch.

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

Natural gas and electricity rates vary significantly based on location, and pricing can change over time, too. It’s possible that in locations where natural gas is particularly inexpensive, it will cost less than grid-based electricity will. However, you should also factor in the generator’s initial costs and maintenance needs, as well as its noise level and if it can comfortably power all your home appliances.