Liquid gas (LPG) is a colourless and odourless energy medium which is heavier than air. As a source of energy, it differs considerably from natural gas and electricity, as it can be stored and transported in containers designed for this purpose. When slightly compressed, it becomes liquid, and this is an advantage - one litre of liquid LPG is the equivalent of 270 litres of gas. Depending on the source and the way of use, the percentage composition of LPG can range from almost 100% of propane to 100% of butane. LPG burns easily in the air and has a high energy content, which makes it an excellent fuel for heating, cooking and automotive use.

Although propane-butane and natural gas have the same applications, LPG has a higher calorific value. This means that it is more caloric than natural gas, which offers better performance in some applications like cooking and heating.

There are two sources of LPG - natural processing of gas and crude oil refining. In the natural processing, gas comes directly from deep underground reservoirs as a mixture of gases and liquids in the gas. In the crude oil refining 3% of such a mixture of gases is obtained from a barrel of oil, however refineries are able to process up to 40%.

Basic information about the physical and chemical properties of a mixture of propane-butane and petrol. The values given below are approximate values.
 

How does LPG work?

When using an LPG system, a car works exactly in the same way as on petrol. Everything in the car remains the same, except for the fact that it has a separate fuelling system for the alternative fuel.

Converted vehicles become "bi-fuel" - when driving the fuels are switched automatically or can be switched manually at any time.

Due to the fact that LPG is much cleaner and therefore environmentally friendly fuel, better combustion of the mixture helps to reduce the amount of harmful substances present in exhaust gases. The pollution with carbon dioxide can be decreased by 10 - 15% , with carbon monoxide - by 20%, and with hydrocarbons - by 55 - 60%. There are no emissions of sulphur and lead compounds, as gaseous fuels do not contain lead compounds at all, while sulphur compounds occur in them only in negligible amounts.

LPG is safe.

Modern LPG systems in cars are safe in use. All LPG tanks are rigorously tested and are much stronger than conventional fuel tanks. In the event of an accident involving a car with an LPG system, the system can withstand enormous impact forces without deformations or leaks. LPG systems have many protections

LPG systems satisfy many requirements, including safety requirements:

• 3 mm thick wall of the gas tank, which is tested many times above its normal operating pressure.

• Two solenoid valves (on the tank and under the hood), which stop the flow of gas to the engine when the engine stops working for any reason.

• Safety valves for the tank and the system to prevent any increases in pressure that could damage the system or be dangerous.

• Two non-return valves of the multivalve on the tank - for fuelling and supplying the LPG system, if the gas supplying pipes are suddenly punctured.