Difference between Oil and Gas in heating

Updated on August 2, 2016

Which is the better heating fuel in terms of efficiency, economy, and safety? We’ll lay out the facts and let you decide.


Home heating oil
Home heating oil spill

Heating oil comes from crude oil processed in big oil refineries, and is used as fuel oil for boilers and furnaces in buildings. Heating oil provides 138,500 BTU (British thermal units) per US gallon or 38.6 megajoules per liter. It also weighs 8.2 lbs per US gallon or 0.95 kg per liter.

Delivered using tanker trucks to commercial, residential, and municipal buildings, heating oil is usually kept in storage tanks located in basements, garages, or even in nearby buildings.

There are several advantages to using oil heat, and true enough, its use has improved through the years. Greenhouse gas emissions from burning heating oil have been reduced by 30% within the last four decades. Sulfur in heating oil is harmful to both plants and animals. In the past, heating oil contained 1% sulfur, but this has been reduced to 0.25% within the last 20 years.

Systems for oil heating can use water, warm air, steam, or hydro-air that can supply a whole house with heat, hot water, and even heat up pool water. The efficiency of oil heat systems has gradually improved as well, making it more affordable and effective, providing heat as needed.

Heating oil is also safe as it won’t ignite if a match is dropped in it. It will simply go out as if the match had been dropped into a pail of water. It will vaporize when heated to 140 degrees, so it won’t even burst into flames. This is actually the principle behind using heating oil. The oil is preheated in the oil heating system until it becomes vapor, then it is ignited in a furnace or boiler.

Oil leaks from pipes and tanks can be a very serious matter. Considered as a hazardous material, strict regulations are in place to ensure that heating oil is properly transported, stored and burned. It is not considered a clean energy source as it releases carbon dioxide when burned.

The price of oil, although it has gone down significantly in the last few years, is unstable and may go up depending on the supply and demand.


Gas, or natural gas is a naturally occurring mixture of methane, carbon dioxide, hydrogen sulfide, nitrogen, helium, and other higher alkanes. It is a fossil fuel, formed from decaying animal and plant matter that has been exposed to great amounts of heat and pressure under the earth’s surface.

Natural gas can be found in underground formations deep below the earth’s surface and in coal beds containing hydrocarbon reservoirs. It is also found near petroleum deposits.

One of the primary uses of gas is for generating heat. In the US, most residential homes would prefer gas heating than any other option. One reason is that natural gas is cheaper. Case in point: a tank with a cubic foot of natural gas would produce more heat than a cubic foot of heating oil would.

Natural gas supply, though non-renewable, is currently stable, which means the price is stable as well.

There are a few downsides to using natural gas for heating. One is the possibility of gas leaks which can cause big explosions or even carbon monoxide poisoning in residential homes.

Oil vs Gas in Heating

So, what’s the difference between oil and gas in heating?

Heating oil is chosen as a heating fuel as it is a safer option. It is not combustible, and it turns to vapor at 140℉. A bucket full of heating oil will not burn up even if a lit match is dropped into it.

Heating gas leaks are hazardous, as they can either cause a big explosion or carbon monoxide poisoning. However, oil is also considered a hazardous material, and strict regulations are in place to ensure its safe handling, storage, and transport.

Heating oil releases carbon monoxide into the air when burned. On the other hand, natural gas is safer to burn as it releases 29% less carbon dioxide than oil. It also releases lesser amounts of nitrous oxide and sulfur dioxide – known pollutants produced by fossil fuels.

The price of oil is a moving target and is affected by so many factors. Natural gas is more stable in terms of availability, but its price range varies depending on the geographical location.

Comparison chart

Non-combustible in liquid formHighly flammable
Produces carbon dioxide when burnedProduces 29% less carbon dioxide than heating oil
Price is unstablePrice is relatively stable