Autogas is the term generally used for Liquefied Petroleum Gas (LPG). Autogas is a high quality energy source and is obtained as a by-product of the distillation of crude oil and the processing of natural gas. It is a mixture of mostly propane and butane and while it is a gas at room temperature, it reverts to liquid when under pressure, making it possible to store within the cars tank.

Australia has an abundance of LPG sources for future use and will be the fuel of necessity long after crude oil has become too valuable to turn into petrol. Compared to petrol, autogas has a higher octane content (according to the RON - research octane number, method) as listed below. The higher octane rating means that the combustion of LPG is smoother and pre-ignition (pinging) is eliminated.

Octane Content Comparison

Unleaded Petrol: 98
Lead Free: 95
LPG: 111

Current Users of Autogas

Italy leads the field with over a million vehicles on the road, the Netherlands, North America and Mexico each have just under half a million. By far the biggest consumer of Autogas however is Japan, which uses over 1,800,000 tones a year. This is hardly surprising given the countries population density and the pollution problems of its major cities such as Tokyo and Yokohama. Over 90% of all taxis in Japan are powered by Autogas. Already 4 million cars worldwide are running on LPG and this figure is fast increasing everyday.

The Safety Record

Autogas has an excellent safety record throughout the world, both in terms of its storage, transportation and use. Extensive safety tests have been undertaken with respect to its use and the conclusions reached are that it is substantially safer than petrol due to its more robust fuel tank being more resistant to impact damage. Also the electronic solenoid valves close whenever the engine stops turning thereby stopping the fuel at the tank. All tanks are fitted with relief valves that provides an escape for the gas should the tank come in contact with extreme heat. Tanks are not filled with more than 80% of total capacity. This ensures there is sufficient room for the liquid to expand on hot days.