It might seem counterintuitive, but installing a generator transfer switch will save you money in the long run. While you’ll have to pay between $400 and $2,500 to have the transfer switch installed, you’ll recoup that amount later on when you don’t have to pay for expensive repairs to your appliances, devices, and electrical system that may have burned out, overloaded, or stopped working due to a sudden loss of power or an incorrect hook up of a generator to your home. 

Natural gas generators are designed to run for extended periods of time, such as power outages during a natural disaster. Since there’s no limit to the supply of natural gas, they don’t need to stop for refills. However, generators do need maintenance, including pauses to check and add oil. Constantly running them will also cause a lot more wear and tear, leading to a shorter lifespan.

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.

To power a central air system during a power outage, the whole-house generator will need to be at least 5,000 watts, and this number will significantly increase for larger units. Check the specific wattage requirements of your AC unit to choose the right generator size. Consider consulting a generator installer to ensure your whole-house generator meets your electrical load needs.