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Want a Gas Fireplace? Here's How Much It Will Cost to Run It

A gas fireplace can add warmth to those chilly autumn nights, but it comes at a price.

AJ Dellinger Contributor
AJ Dellinger is a contributor to CNET.
AJ Dellinger
4 min read
a gas fireplace

A gas fireplace creates great ambiance in the fall and winter, but it comes at a price.

ryasick/Getty Images

There are few things more romantic or appealing than the thought of sitting in front of a crackling fire while sipping from a mug of hot cocoa as the snow falls down outside. It's the ideal way to spend an otherwise chilly winter evening.

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So with that in mind, why not fire up your gas fireplace and run it all winter long to keep you warm? Well, here's the thing: All that warmth ain't free. It comes at the cost of an increased utility bill, which you'll need to pay to maintain your comfort throughout the winter. 

So how much does it actually cost to run a gas fireplace? We'll walk you through what you can expect to pay as you try to stay warm as it gets colder out. (You can also find out how much it costs to run a space heater, and how much you can save by setting your thermostat to this temperature and by changing your furnace filters.) 

How do gas fireplaces work?

While the more traditional image of a fireplace includes tossing logs on a fire, gas fireplaces have been growing in popularity over the years. There are a number of reasons for this: primarily the fact that it's much simpler, more efficient, produces no mess and requires no clean-up after use. 

But not all gas fireplaces are created equal. There are two common types of gas fireplaces, vented and vent-free. A vented gas fireplace works via combustion, taking air from the outdoors through an outer vent, heating it, and redistributing it through the room to provide additional heat. A ventless system is more contained than that. It uses air already in the home, heats it, and distributes it while producing moisture as a byproduct. 

Ventless gas fireplaces are more energy efficient but need to be managed and installed in a room of the proper size because of the moisture. A vented gas fireplace is less efficient but requires less management and is more of a one-size-fits-all approach to your heating needs.

What is the cost of running a gas fireplace?

The first thing that you'll need to consider is the amount of space that you'll be heating. You'll want to make sure your fireplace is properly equipped to heat the space where it's being used. Trying to heat a space that's larger than the fireplace is capable of effectively heating, you'll run the risk of running up your energy bill.

You'll also want to consider the energy efficiency of your gas fireplace. Ventless fireplaces typically experience significantly less wasted energy and continuously heat the air that is filtering through the space to keep you warm. Vented fireplaces are pulling air from an outer vent and heating it and can experience energy loss if the fireplace isn't properly sealed. This can add to your overall energy bill as your fireplace will be less efficient in heating your space.

Finally, you need to consider the cost of gas in your state or municipality. Usually, your utility provider will tell you the cost of natural gas usage. This is typically expressed in cost per therm, which is equivalent of 100,000 British thermal units, or Btu. This is tricky since your fireplace will likely tell you its fuel consumption requirements in Btu per hour. You can expect this to be anywhere from 10,000 Btu per hour to up to 90,000 Btu per hour.

To determine the cost of running your fireplace, take the cost of running it in Btu per hour, multiply it by the per-therm cost of gas in your area (the national average is $1.63, and divide that by 100,000 to get the cost per hour.

Here's an example to help illustrate this, with a fireplace with a Btu rating of 30,000: (30,000 x 1.63) / 100,000 = 0.49. That means it will cost about $0.49 per hour to run your fireplace. If you run your fireplace for 8 hours a night, it will cost $4.41 a day. That can cost you $132 a month to run if you use the fireplace for 8 hours a day every single day. 

Do settings affect the cost of running a gas fireplace?

Some gas fireplaces will have settings available that allow you to adjust the level of heat. In effect, this also lowers the level of energy consumption, using less of the Btu than the fireplace is capable of using at its maximum capacity. If you run your fireplace at a lower setting, it can cut down your energy consumption by half, assuming the fireplace uses half of its full capacity at this level. 

A gas fireplace is a great way to provide yourself with the comfort of heat during the winter months. But it does come with a cost. Make sure you determine how much it will cost to run your gas fireplace during these months and budget accordingly, or you might be caught off guard at just how much it can cost to stay warm through the winter. The comfort of the heat is welcome, but that must be balanced alongside the potential cost. 

For more money-saving tips, check out seven simple ways to lower your utility bills this winter and how much you can save by turning off your lights at home.

Here Are 23 Ways to Save On Your Electric Bills Right Now

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