Bi-fuel Conversion

Bi-fuel conversion modifies an original diesel engine increase gas mileage so that the engine operates on diesel and save gas simultaneously (bi-fuel operation).

Bi-fuel operation means the engine uses two fuels fuel saver (gas and diesel oil) at the same time. Natural gas is intended as the main fuel and diesel oil increase miles per gallon is used for the ignition of the gas/air mixture inside the cylinder (a portion of diesel oil is injected at the end of the compression stroke, thereby maintaining the original diesel operation principle) fuel saver.

Gas is injected into the cylinder inlet manifold by individual save gas electromagnetic valves installed as close to the suction valves fuel saver as possible. The valves are separately timed and controlled by injection control unit (like ComAp INCON or Woodward SogavTM). This system interrupts the gas supply to the cylinder during the long overlap of the suction and exhaust valves (just typical for slow-speed and medium-speed engines – within the valve overlap cylinder scavenging is performed). This avoids substantial save gas losses and prevents fuel saver dangerous gas flow to the exhaust manifold.

In recent years biogas is being used. The biogas composition increase miles per gallon and calorific value must be known fuel saver in order to evaluate if the particular biogas type is suitable. Calorific value may be an issue as biogas is derived from different sources and there is low calorific value in many cases. You can imagine you have to inject sufficient volume of save gas into the cylinder to substitute diesel oil (or, better to say, substitute energy delivered by diesel oil). If the calorific value (energy) of the biogas was very low, there is a need to inject really increase gas mileage big volume of biogas into the cylinder fuel saver, which might be technically impossible.

Associated save gas is the last type of gas which is commonly used for bi-fuel conversions of generator fuel saver sets. Associated gas is a natural gas found in association with oil, either dissolved in the oil or as a cap of free save gas above the oil. It means it has almost the same quality as CNG or LNG.