Liquid petroleum gas (LPG) has been used as an automotive fuel for decades, offering drivers an alternative to conventional gasoline and diesel. Also known as autogas when used in transport, LPG can help reduce emissions while allowing vehicles to continue using familiar internal combustion technology.
What is liquid petroleum gas?
LPG is a colorless, flammable mixture of light hydrocarbon gases, mostly made up of propane and butane. While it exists as a gas under normal conditions, it can be stored as a liquid under pressure, making it practical to transport and store in dedicated tanks.
Currently, most of the world’s demand for LPG is met through it being a by-product of crude oil refining and natural gas processing.
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How is LPG produced?
Most of the world’s LPG is generated during two industrial processes - crude oil refining and natural gas processing.
During oil refining, propane and butane are separated from other hydrocarbons as crude oil is converted into products such as gasoline and diesel. Similarly, natural gas processing removes these gases before natural gas is supplied for domestic and industrial use.
Once separated, the gases are compressed into liquid form, allowing them to be stored and transported efficiently before being distributed for applications including heating, cooking and transport.
LPG has been widely adopted by fleets including taxis, delivery vans and buses
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How do LPG vehicles work?
Most LPG-powered vehicles use a bi-fuel system, allowing them to run on both gasoline and LPG.
Rather than replacing the original fuel system, an additional LPG tank, fuel injectors, and pressure regulator are installed alongside the existing gasoline components. In many cases, this is through an aftermarket conversion kit, although some manufacturers have also produced factory-built LPG vehicles.
When using these kits, the engine generally starts by burning gasoline before automatically switching to LPG once it has reached operating temperature. If the LPG tank becomes empty, the vehicle returns to gasoline, allowing drivers to continue their journey without interruption.
This flexibility enables drivers to benefit from LPG while retaining the convenience and familiarity of a conventional gasoline-powered vehicle.
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Where is LPG used?
LPG is well suited to vehicles which are driven heavily and operate in urban environments.
It has been widely adopted by fleets including taxis, delivery vans and buses. These vehicles can benefit from lower tailpipe emissions, including reduced nitrogen oxides (NOx) and particulate emissions, while also helping operators manage running costs.
The ability to convert existing gasoline vehicles has also contributed to LPG's adoption, allowing operators to continue using their existing vehicles rather than replacing them entirely.
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Is LPG part of the future of mobility?
The transition to lower-emission transport cannot rely on just one technology. Instead, different fuels and powertrains are likely to play different roles depending on vehicle type, operating conditions and regional requirements.
LPG shows how established combustion technology can be paired with alternative fuels to support lower-emission mobility in suitable applications. While electrification, hydrogen and other alternative fuels will continue to develop, LPG remains another option within an increasingly diverse transport landscape.
At Horse Powertrain, we believe the future of mobility requires combining engine technologies with a range of fuel solutions to meet different customer needs. Our expertise across different types of powertrains helps support this transition to lower-emission mobility.
Find out more about our next-generation powertrain solutions here.
