Carbon Footprint of Heater Emissions: Types, Size, Heat Emissions Per kWh

The carbon footprint of heater emissions using gas or electricity can differ, but both of them emit enough to affect the environment.

Heating is crucial for survival, especially in colder climates, but many people wonder how much does it affect your carbon footprint overall, and are there ways to limit the effect of the carbon footprint of heater emissions?

By understanding the metrics behind fuel emissions used for heat can be tricky. There are a LOT of factors involved.

This complete guide outlines how to measure the carbon footprint of heaters based on the most common types and sizes.

Carbon Footprint of Heater: Types of Heating Systems

There are various types of heating systems and each one will emit its own amount of carbon emissions.

On average the heating of a home will account for 17-32% of a household’s energy usage.²

Combined with cooling, this can add up to 441 million tons of CO₂ a year.³

There are four main types of heating systems: central heat furnaces, traditional boilers, heat pumps, and ductless heating/cooling systems.

These can use varying sources like natural gas or electricity and it’s based on the level of those sources that will lead to the carbon footprint of heater emissions.

Types of Fuels

In general, a heater is powered by either electricity or fuel, with electricity-producing the least amount of emissions at 0.18 kg CO₂/kWh.⁴

Fuels produce a higher amount of carbon emissions with coal being the highest at 0.40 kg CO₂/kWh followed by heating oil at 0.30 kg CO₂/kWh, liquefied petroleum gas at 0.24 kg CO₂/kWh, and finally natural gas at 0.21 kg CO₂/kWh.⁴

However, it’s not so simple, since that electricity amount comes from electricity that is powered by solar or wind, but it’s important to keep in mind that electricity is also produced in the U.S. with those fuels listed.

So, in many cases, the amount listed for those fuels can be considered similar, if not higher, when considering electric sources.

Carbon Footprint of Home Furnace

Furnaces and boilers that use natural gas can produce anywhere from 6,400 lbs of CO₂ to 8,000 lbs of CO₂ per year.⁵ This range is dependent on the area and frequency of usage.

Electrical furnaces and boilers can be more energy efficient up to a point, but this also depends on the area and frequency of usage.

The carbon footprint of heater emissions of electrical heaters can range from 4,700 lbs of CO₂ to 9,900 lbs of CO₂ annually.⁵ It’s clear that the colder the climate, the more practical and energy-efficient natural gas can be.

Another factor to consider is the material that the furnace is made of and the production of the furnace. Furnaces are made of aluminized steel or stainless steel and many of the fixtures are made of copper or brass.

Although it is hard to calculate the exact amount of carbon emissions any given furnace emits during its development, it’s important to remember that stainless steel is recyclable and therefore has a substantial lifespan. For each ton of stainless steel produced, there is a range of 0.20 to 0.60 tons of CO₂ produced.⁶

However, there is a more energy-efficient option regardless of the source and the cleanliness of the grid.

Heat Pump Carbon Footprint

If you are looking for energy-efficient heaters, a heat pump is the direction you want to go in. You may be wondering, how does a heat pump work?

The heat pump simply transfers hot or cool air in the house outside or vice versa, depending on the time of year. It uses technology similar to an air conditioner or refrigerator to take surrounding hot air during the winter and pump it into the home,⁷ while during the summer it will pump out hot air.

What Is a Carbon Footprint?

First, we have to answer, what is a carbon footprint? A carbon footprint is the cumulation of carbon emissions an activity involves.

For instance, traveling has its own carbon footprint, and differs based on severity depending on whether you travel by car or plane.

A carbon footprint is calculated by tracking greenhouse gasses including methane and carbon dioxide that result from daily activities, such as transportation, food, household energy, and consumption.¹

Carbon Footprint of Heater: Heat Pump vs. Furnace

Heat pumps can lower household carbon emissions by 36-64%.⁸ This means an equivalent per year of 2.5–4.4 metric tons of CO₂ per household.⁸

This is even with a grid that hasn’t been adapted yet to use greener energy.

This is because heat pumps are more efficient than gas furnaces, especially in colder climates,⁹ where the most efficient heating is most necessary. If you replace your furnace water heater with a heat pump water heater you can lower your annual household carbon footprint of heater emissions by 2,000 pounds of CO₂.²

Benefits of Propane

Against a traditional boiler, propane still emits 30% fewer carbon emissions.¹⁰ The issue with electrical heating is that it still can use natural gas or coal as its source.

In fact, two-thirds of US electricity uses fossil fuels as its source. Electrical plants will use these sources to turn into heat to create electric energy, which is then sent to the home to be turned once again into heat.

The use of propane cuts out that process, however, it’s important to remember that propane and all-natural gasses must be harvested. When using them in the home you may only consider the carbon emissions that come from using the gas itself and not the process by which it is attained.

Pipelines, transportation, and the digging required to access these natural gasses can be taxing on the environment, and most gasses come from the same source but are obtained through different processes. For instance, propane can be produced through the process of crude oil refining or natural gas processing.¹¹