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.

Yes, natural gas generators can work without electricity. Natural gas generators are a common type of backup or whole-house generator that operates when the electrical grid isn’t working. The trick is using a transfer switch (which usually needs to be installed with the generator) that safely switches the home electrical system from the power grid to generator power when needed.

Costs depend on generator type, labor, and additional wiring or transfer switch requirements.

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.