Is It Cheaper To Run A Natural Gas Fireplace Or The Furnace?hat is the Meaning of Cheaper?

When you say cheaper, it is in comparison of gas with another fuel, which is obviously furnace in this context. The root meaning is saving on money, which is to get more heating from lesser fuel. You can consider the parameters like fireplace design, construction, materials, and the fuel consumption volume. It is obvious that you want to know how gas works cheaper than a furnace.

Efficient Gas Fireplace Design

The gas firebox is made of copper, steel, or other heat-conducting materials. So, it can get heated with a relatively lesser volume of fuel within a short time. The transmission rate of heat to the external environment is faster, efficient and consistent. So, you can save on gas.
Exteriors of the firebox could be made of ceramic, brick, or other insulating materials which prevent heat loss. Hence, the interiors of the gas fireplace get more heat due to reflection from the internal surfaces. It also helps in saving on fuel.
Gas fireplaces have fan blowers which distribute the heat to the eight corners of the room. So, optimum heating is sufficient to keep the room warm for a relatively long time.
Cost of Gas per Gallon
One gallon of gas will cost you much lesser than the same volume of the furnace. The heat generated by one unit volume of gas is much higher than the same volume of the furnace. Moreover, the availability of good quality furnace could be difficult, unless you have a continuous supply source.
Inflation in the cost of the furnace is more frequent compared to gas. If you pay (Canadian Dollar) CAD 1 for one volume of furnace today, the cost may increase to CAD 2 or CAD 3 within the near future. The gas price may increase to CAD 1.3 or CAD 1.4 in the same period. Now, you can evaluate how much cheaper it is to use a gas fireplace.