Frequently Asked Questions

The terms Bi-Fuel and Dual Fuel are often used interchangeably.

No. The conversion technology has been designed to allow for in-field retrofit of diesel engines without the need to change or modify the design of the engine. The conversion hardware is mounted externally on the engine and does not require modification of the engine or alteration of any critical engine parameter.

Most OEM engine warranty programs do not prohibit the use of aftermarket parts or technologies. In brief, the policy of OEM's is that they neither recommended nor endorse aftermarket technologies, however, the use of these products does not automatically void the validity of the engine warranty. In practice, if a converted engine has a failure under warranty, the OEM, in conjunction with technical personnel, make a determination as to the cause of the failure. If the cause is obviously unrelated to Dual-Fuel, the OEM's have historically honoured the warranty and repaired the engine. If the cause is determined to be Dual-Fuel related, the manufacturer of the Dual-Fuel System will cover repair costs under its warranty program.

Because of the very high ignition temperature of natural gas (approximately 650 °C), sufficient heat is not generated during the diesel compression stroke to ignite 100% natural gas. As such, dedicated gas engines employ spark plugs and an ignition system to facilitate combustion of the air-natural gas mixture. In contrast, during Dual-Fuel operation, a reduced quantity of diesel fuel acts as the ignition source for the air-gas mixture; this process is often referred to as pilot ignition.

Under normal circumstances, engines converted to the Dual-Fuel do not suffer any horsepower losses while operating in Dual-Fuel Mode. Because the System maintains OEM compression ratio values, peak horsepower and efficiency levels of the converted engine remain on par with 100% diesel operation. In some circumstances, the engine may be de-rated in Dual-Fuel mode due to shortcomings in gas supply composition and / or quality.

The Dual-Fuel technology has been designed to maintain OEM specifications of all engine temperatures including engine coolant temperature, oil temperature, exhaust gas temperature and intake air temperature. The Dual-Fuel System replaces diesel fuel normally consumed by the engine with an equivalent quantity of natural gas, relative to the heat value of each fuel. As such, engine air-fuel ratios during Dual-Fuel operation remain largely equivalent to 100% diesel operation, resulting in normal peak exhaust gas temperatures and associated peak engine thermal loads.

As explained above, the Dual-Fuel System replaces diesel fuel with an equivalent quantity of natural gas. This process results in the same net fuel burn vs. load as would be experienced during 100% diesel operation.

Generally speaking, operation in Dual-Fuel mode has no negative effects on engine wear rates and durability. As explained above, because engine thermal loads are equivalent to 100% diesel operation, no excess wear of combustion chamber components (pistons, rings, valves, injectors, etc.) occurs. In addition, many users of Dual-Fuel have reported positive benefits relative to engine wear including extended oil change intervals and extended time between overhauls. This is primarily the result of the cleaner burning characteristics of natural gas compared to diesel fuel.

Fuel cost savings resulting from operation in Dual-Fuel mode will vary according to the respective cost of each of the fuels. If there is a significant cost differential between the cost of diesel fuel and the equivalent quantity of natural gas (heat value basis) in favour of the natural gas, significant fuel cost savings would result. The closer the fuels are in price, the lower the fuel cost savings will be during Dual-Fuel mode. In addition to fuel cost saving, engine maintenance savings (as explained above) may also contribute to the economic benefit of Dual-Fuel operation.