Heat Pump vs Gas Furnace Calculator

Stop the heating wars. Compare the exact physics and running costs of an electric heat pump versus a gas furnace based on your local utility rates.

3.0x

The 'Multiplier'. A COP of 3.0 means it generates 3 units of heat for every 1 unit of electricity. (Drops lower in freezing weather).

90%

Old furnaces are 80%. High-efficiency modern furnaces hit 95%+. Impossible to exceed 100%.

How much heat your house actually needs all winter. Look at a past winter gas bill (usually 50 to 150 Therms).

For mathematical estimation only. Excludes fixed connection fees and exact weather-variable COP drops during extreme cold snaps.

Running Cost Comparison

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The Heating Wars: Gas vs. Electricity

The biggest debate in home energy right now is whether to upgrade a traditional gas furnace to an electric heat pump. Government subsidies are pushing hard for electrification, but many homeowners worry that their electricity rates are simply too high to justify the switch. Our Heat Pump vs. Gas Furnace Calculator strips away the politics and looks strictly at the physics and your local utility rates.

How Can a Heat Pump Be Over 100% Efficient?

To understand the math, you have to understand how the machines work:

  • •Gas Furnaces (AFUE): A furnace burns fuel to create heat. Because some heat is always lost out of the exhaust exhaust pipe, it is physically impossible for a furnace to be 100% efficient. A modern furnace is usually around 90% to 95% efficient.
  • •Heat Pumps (COP): Heat pumps do not *create* heat; they *move* it. Like a refrigerator running in reverse, they extract ambient heat from the outside air and compress it into your house. Because moving heat requires far less energy than burning fuel to create it, a heat pump operates at a 'Coefficient of Performance' (COP) of 3.0 to 4.0—meaning it produces 3 to 4 units of heat for every 1 unit of electricity consumed (300% to 400% efficiency).

The Cold Weather Myth

You may have heard that "Heat pumps don't work in freezing weather." Ten years ago, this was true. Today, modern 'Cold Climate Heat Pumps' can extract heat from the air even when it is negative degrees outside. However, as the temperature drops, the system has to work much harder. In freezing weather, a heat pump's COP might drop from 3.5 down to 2.0. This is why our calculator lets you lower the COP slider to accurately model a harsh winter.

The Ultimate Financial Cheat Code

If your calculator shows that the Heat Pump is cheaper, there is one massive advantage we haven't even mentioned: A Heat Pump is also an Air Conditioner. By replacing a broken gas furnace with a heat pump, you get brand new central AC for the summer included in the same unit. If you want to completely erase the cost of running it, plug your usage into our Solar System Sizing Calculator and find out if a roof array makes financial sense with the Solar ROI Tool!

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Frequently Asked Questions

Is a Heat Pump just an Air Conditioner?

Essentially, yes. An air conditioner cools your house by pulling heat from inside and dumping it outside. A Heat Pump has a special reversing valve that allows it to run backward—pulling ambient heat from outside and pumping it inside. When you buy a Heat Pump, you are buying heating and cooling in one unit.

What is dual-fuel or hybrid heating?

In areas with extremely harsh winters and cheap natural gas, homeowners often install a 'Dual Fuel' system. It uses a hyper-efficient electric heat pump for 80% of the winter, but switches over to a backup gas furnace automatically when temperatures drop below freezing and the heat pump efficiency begins to fall.

What is COP?

COP stands for Coefficient of Performance. It is the metric used to measure Heat Pump efficiency. A COP of 1.0 means 1 unit of electricity creates 1 unit of heat (like a standard space heater). A COP of 3.0 means 1 unit of electricity creates 3 units of heat. Higher is better.

What is AFUE?

AFUE stands for Annual Fuel Utilization Efficiency. It is the metric used to measure Gas Furnaces. An 80% AFUE furnace turns 80% of the gas into heat, while the other 20% escapes out the exhaust pipe. A 95% AFUE furnace is highly efficient, wasting only 5% of the fuel.