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Engine Conversion Systems

Bi-Fuel Kits

Every bi-fuel vehicle has a double fuel system and tank - one for alternative fuel, and one for the back-up fuel (petrol). The engine may start using petrol, but will shift into gas mode shortly after ignition. Should the vehicle run out of natural gas, the engine will automatically switch over to petrol.

Fueling station access for natural gas varies from country to country, and sometimes also in different parts of each country.

OMVL's bi-fuel solutions are powered by either:

  • Compressed natural gas (CNG) - mainly methane, stored at a pressure of 200 Bar, also known as biogas or natural gas or 
  • Liquefied petroleum gas (LPG) - mainly propane and butane, stored at a pressure of about 8 Bar

The CNG and LPG systems have similar solutions when it comes to:

  • Pressure regulators (the LPG version only includes the low pressure part) 
  • Fuel distributors 
  • Injector nozzles 
  • Engine management system (ECU programmed for CNG or LPG) 

With OMVL bi-fuel solutions, the engine is always started on petrol, even if it is set to operate on natural gas (the switch to natural gas, if it has been selected, takes place automatically when the cooling water reaches a temperature of approximately 15 °C).

The refuelling nozzle for LPG can vary from country to country. Two adapters for refuelling accompany every LPG car, to make things easier when travelling abroad.

Bi-fuel Methane

Methane is a combustible fuel that can be obtained in two different ways:

  • Extracted from the earth in the form of natural gas 
  • Produced from organic material in the form of biogas

Apart from being a particularly economical fuel, natural gas produces far lower total emissions of environmentally hazardous and toxic substances compared with petrol and diesel fuel. Natural gas is available in most European countries - with a total of about 3000 refueling stations - these are increasing in number all the time.

Biogas is so far produced and distributed on a fairly small scale. However, interest in this clean and high-quality fuel is growing throughout the world - not least because it can be produced locally virtually anywhere, and has no net contribution to the global warming problem caused by greenhouse gases.

Bi-Fuel LPG

LPG is a mixture of two gases: propane and butane. It is obtained both directly, when oil or gas is pumped out of the ground, and indirectly as a residual product from oil refineries. LPG offers particularly low running cost - at a savings of about 40% compared with running your car on petrol, or about 20% compared with diesel. And just as with natural gas, LPG is a far cleaner fuel than either petrol or diesel. The result is extremely low emissions of harmful substances. What is more, emissions of carbon dioxide are about 11% lower than those from petrol.

LPG is available from about 15,000 refueling stations in Europe, with the greatest concentration in the Netherlands, Belgium, France, Italy, Poland and Great Britain.