When it comes to gas we tend to have two choices – propane, and natural gas. Like many I’ve always had an idea about them, but not a full understanding of the differences. To help clear things up, I’ve done several hours of research on the topic: this article shares what I’ve learned. In short:
Natural Gas is found in the earth, made of mainly methane but also includes propane. We extract propane separately: it’s more efficient, easier to store, more expensive, and heavier than air. Natural Gas is lighter than air and needs to be sourced from a gas network.
In other words – Natural Gas is a raw product that has plenty of uses. One of them includes burning for fuel/heating, which it does well and burns cleanly. Propane is a part of Natural Gas which is extracted separately. It’s amazing as a fuel and is easily stored and transported as liquid. However, it has few other uses than simply being burned for heat.
To make it easier, here’s a quick comparison table.
Differences Between Propane & Natural Gas
|Differences of Natural Gas & Propane|
|Formation||Forms naturally||From processes|
|Elements||Mix of substances||One compound (C3H8|
|Weight||Lighter than air||Heavier than air|
|Compression||Hard to liquify||Easy to liquify|
|Storage||Can't be stored easily||Can be stored easily|
|Fumes||Burns cleanly||Burns (mostly) cleanly|
|Accessibility||Gas network only||Portable canisters/tanks|
|Dangers||Little to none||Asphyxiation|
There’s also a great overview in this video by Petro:
While that’s a good start, we can dive into a bit more detail and investigate these differences further. Read on for more information on the differences, sources, and best uses for each gas.
Where do they come from?
The gases we use at home almost always begin with natural gas. This is created from decomposing plant and animal matter over a millions of years, coupled with high-intensity heat and pressure.
This creates a non-renewable fossil fuel. It’s a hydrocarbon gas made up of many elements, but mostly methane.
The common compounds of natural gas are:
As you can see from the table above, propane is an inherent part of natural gas. However, we often extract it to harness it’s more efficient power and better accessibility.
We get propane from either natural gas processing or petroleum refining.
If we sent natural gas along pipelines as it occurs naturally, it would cause a lot of condensation and operational issues. To prevent this we take out butane, propane, and ethane from it.
Additionally, propane is produced when they ‘crack‘ their petroleum into usable oil or fuel.
Did you know?
Propane comes from the greek ‘pro’ (forward, or first) and ‘pion’ (fat) as it’s the first in the order of fatty acids. Source: Etymonline
Which is more efficient?
Pound for pound, propane is a much more efficient gas to burn. This is (yet) another reason why it’s such a great fuel to transport. As stated in the video above, you get around 2,516BTU’s (BTU is a measure of heat) from one cubic foot of propane.
Alternative, we can only get around 1,030BTU’s from a cubic foot of natural gas.
This makes sense – since propane is extracted from natural gas. It is part of what causes the burn of natural gas normally, and this is even greater when we burn it by itself.
Which is the cheapest?
This answer may vary depending on the market, as prices for both gas types vary.
However, in general, natural gas is typically cheaper to produce the same amount of heat as propane. Despite needing a higher quantity of natural gas to do so.
You can find an updatable comparison table over at AMS Energy – just plug in today’s unit price to compare the ‘cost per million BTU’ of each gas.
At the time of writing, it would cost $14.71 to produce a million BTU worth of heat with Natural Gas. Propane, however, costs $34.04 to do the same thing. That’s 2.3 times more expensive!
How are they stored?
Since natural gas is so light (even lighter than air), it’s extremely hard to compress it enough to be stored in portable containers. One canister just wouldn’t hold enough natural gas to be useful. This is one of the main issues with natural gas, and a main advantage of propane. The only way to access natural gas is to be connected to the gas network. (This can include digging up your garden to connect a pipeline).
We all know that when we boil water it turns into steam when it passes 212F (or 100C). Propane is just the same, except that temperature is -43.6F (-42C)! This means it’s quite easy to pressurize into a liquid for transport and storage, then allowed to become a gas again when we want to release and burn it.
This liquid to gas temperature is a key part of why it’s such a useful gas.
What happens when we burn them?
Despite being a fossil fuel, natural gas burns quite cleanly. It does release carbon dioxide when we burn it, but not to an extreme extent. This is different from other fossil fuels like coal or oil, which release a huge amount of harmful substances.
Since propane is part of natural gas, it also produces lesser amounts of carbon dioxide compares to fuels like coal or oil. However, propane equipment used in enclosed and poorly ventilated spaces lead to a build-up of carbon monoxide or carbon dioxide. This can be highly dangerous – especially since it’s odorless and invisible.
If you experience headache, fatigue, drowsiness or nausea when near an active gas-powered device, please shut it off. Ensure good ventilation around both the container and exhaust.
Uses of Propane & Natural Gas
Propane is an ultimate fuel alternative to a mains-supply.
For any activity where you need fuel but don’t have access to natural gas or electricity, it’s a fantastic solution. Barbeques and portable stoves, in particular, are a great use of propane.
While other alternative gases could be used, propane is ideal because of the transition to gas as it’s being released. It’s easy to move liquid storage doesn’t need to be vaporized, unlike with other gases.
Moving away from the patio – propane is excellent in off-grid appliances. Like off-grid refrigerators. It’s also an excellent fuel for back-up heating and electric generators, thanks to being self-reliant.
However – these are the limits of propane. While it’s an amazing resource, it’s only really good for burning.
Natural gas on the other hand, has many uses. Primarily it’s good as a main source of heating – when it’s available. The connection to the gas network is quite a strict requirement, however!
When connected, it’s a cheaper heating resource than propane – and much more freely available. While it’s preferable to have natural gas, I wouldn’t recommend digging up your garden to fit in a pipeline if you don’t have one already.
Outside of heating, other uses of natural gas are:
- Power Generation: generating electricity through generating gas and steam turbines. In addition, helping to keep renewable energy systems like wind and solar going when they aren’t generating as much power as needed.
- Transportation: While not incredibly popular in the US, some countries have plenty of vehicles which rely on natural gas – the biggest propents being China, Argentina, India, Iran, and Brazil. It’s about efficient as petrol, but less so than diesel.
- Fertilizer: Natural gas is a key part of producing ammonia, which is used in fertilizers.
- Feeding Animals: Natural gas is ‘eaten’ by several types of bacteria, on which fish and animals feed.
- Manufacturing: Steel, fabric, glass, plastics, and even paint use natural gas in their production processes.
Propane and Natural Gas are the two most common gas sources used throughout the country. However, it can be tricky to know which one is best – and for what reasons.
I hope this guide has helped you understand these two common fuels a little more. That you now understand why propane comes in canisters, while natural gas can only come out of a pipe!
As Appliance Analysts, we’ve gone into detail on many appliances which use propane – some of our related articles are listed below. If this guide has helped you, please consider supporting us by checking them out!
Thank you, and have a great day!