How Many Watts Does a Gas Furnace Use?

The world of heating and cooling can be quite complex, especially when considering the power consumption of various appliances.

One of the most common queries we receive is how many watts of electricity a furnace uses. Today, we’ll demystify this topic, comparing gas furnaces and electric furnaces and providing tips on how to reduce furnace electricity costs.

How Much Electricity Does a Gas Furnace Use?

A gas furnace uses about 0.4-0.6 kilowatts (kW) per hour on average. Let’s break down the costs at a rate of 23 cents per kWh:

Hour

At 0.4-0.6 kW per hour, the cost of running a gas furnace for one hour ranges from 9.2 cents (0.4 kW * 23 cents) to 13.8 cents (0.6 kW * 23 cents).

Day

Over a 24-hour day (assuming the furnace runs for 5 hours), the furnace consumes between 2 kW (0.4 kW * 5) and 3 kW (0.6 kW * 5). The daily cost ranges from $1.15 (2 kW * 23 cents) to $1.73 (3 kW * 23 cents).

Month

In a month (30 days), a gas furnace consumes between 60 kW (2 kW * 30) and 90 kW (3 kW * 30). Hence, the monthly cost ranges from $34.50 (60 kW * 23 cents) to $51.75 (90 kW * 23 cents).

Year

Annually, a gas furnace will consume between 720 kW (2 kW * 360) and 1,080 kW (3 kW * 360), resulting in an electricity cost ranging from $414 to $621.

How Much Electricity Does an Electric Furnace Use?

Electric furnaces have a higher power consumption, averaging between 10-50 kW per hour. Let’s calculate the cost:

Hour

In an hour of continuous use, an electric furnace consumes 10-50 kW. Given the electricity price of 23 cents per kWh, the cost ranges from $2.30 (10 kW * 23 cents) to $11.50 (50 kW * 23 cents).

Day

Over a 24-hour day (assuming the furnace runs for 5 hours), an electric furnace uses between 50 kW (10 kW * 5) and 250 kW (50 kW * 5). The daily cost ranges from $11.50 (50 kW * 23 cents) to $57.50 (250 kW * 23 cents).

Month

In a month (30 days), an electric furnace consumes between 1,500 kW (50 kW * 30) and 7,500 kW (250 kW * 30). Therefore, the monthly cost ranges from $345 (1,500 kW * 23 cents) to $1,725 (7,500 kW * 23 cents).

Year

Over a year, an electric furnace consumes between 18,000 kW (50 kW * 360) and 90,000 kW (250 kW * 360). Thus, the yearly electricity cost can range from $4,140 to $20,700.

How to Reduce Furnace Electricity Costs?

Regardless of the type of furnace, implementing energy efficiency measures can reduce your monthly cost and overall energy usage:

  1. Energy Star Furnaces: Look for furnaces with the Energy Star label, which are more energy efficient.
  2. Variable-Speed Motor: Compared to a standard fan motor, variable-speed fan motors adapt to your home’s heating needs, using less electricity when full power isn’t required.
  3. Regular Maintenance: Keep your furnace running optimally with regular checkups.
  4. Insulation: A well-insulated home maintains a constant temperature, reducing furnace use.
  5. Humidity Control: Homes with controlled humidity levels tend to feel warmer, reducing the need for continuous heating.

Gas Furnace VS Electric Furnace

In terms of energy usage, gas furnaces generally consume less electricity due to their use of natural gas for the main heating operation. However, the cost difference also depends on the price of electricity and gas in your area.

What Size Generator Do You Need for Your Gas Furnace?

To power a gas furnace during outages, you’ll need a generator capable of supplying the running wattage of your furnace. A generator with a capacity of 10000 watts should suffice for most household gas furnaces.

What Size Generator Do You Need for Your Electric Furnace?

For an electric furnace, the generator size will need to be much larger, typically in the 15,000-25,000 watt range, depending on the exact power consumption of your furnace.

How Long Can a Battery Run a Gas Furnace?

A fully charged deep-cycle battery (around 100 Ah) can run a standard gas furnace for about 2-3 hours. Remember, this may vary depending on the furnace’s exact power requirements.

Conclusion

Understanding the power consumption of your furnace, whether gas or electric, is a crucial step towards managing your annual heating expenses and reducing your electric bills.

As always, ensure your furnace is well-maintained and operating efficiently to save on costs and energy.

Be mindful of your energy usage, and you can enjoy a warm, comfortable home without the worry of excessive costs from your electric suppliers.

About Roy Cohen

Roy Cohen has a burning passion for heating, cooling, and ventilation. He aims to help you save money on expensive repairs and bring you the best HVAC products. He has years of experience behind him in HVAC repair and garage maintenance.

You can find Roy at his LinkedIn or his email: [email protected]