3.3 Propane

Propane has been powering vehicles since the 1920’s and was popularized as a vehicle fuel in the 1950’s and 1960’s. Today there are over 10 million propane-powered vehicles worldwide and the number is growing. Historically, in North America, the large original equipment manufacturers (OEM’s) such as Ford, GM and Chrysler have offered, and withdrew, on occasion, a very limited number of propane-powered vehicles. The majority of the North American demand for propane-powered vehicles has been satisfied with aftermarket propane-conversion technology. Recently, Ford, through an alliance with Roush Enterprises Inc., has announced the introduction of a propane-powered pickup truck for the US marketplace beginning in 2008.

Prior to the introduction of advanced electronically-controlled engines, the propane-conversion equipment on engines consisted of a relatively simple carburetor with a rudimentary vaporizer. This carburetor-based technology continued to evolve into the 1980’s and 1990’s with improvements to the carburetors and with the installation of primitive electronics controlling the air/fuel mixture. During the late 1980’s and early 1990’s gasoline engines changed significantly. Driven by EPA emissions requirements, gasoline engine manufacturers abandoned carburetor technologies and embraced fuel-injection technology to gain precise control over air/fuel mixtures. As well, second Generation Onboard Diagnostics (OBDII) became mandatory on all engines. The propane-conversion technology providers did not keep up with the evolution of gasoline engine technology. The industry continued to install carburetor-based technology that resulted in operational problems (backfires, reliability) and poor environmental performance that rendered the carbureted propane technology unviable.

In the late 1990’s North American and European technology companies began to develop propane fuel-injection technologies with sophisticated electronic controls. Typically these technologies work in combination with the OEM electronics, and utilize injectors designed specifically for propane. This technology has lead to excellent emissions results along with drivability and performance that is equivalent to gasoline. A number of these technologies are available in North America and fleets have logged millions of kilometres utilizing the technology; proving its capabilities to meet the rigors of fleet use.

As these systems have become increasingly sophisticated and more costly to manufacture, the cost of the conversion components has risen from $1,500 for the old technology in the 1980’s to approximately $5,000 for the current fuelinjected technology. While the old carbureted technology is still available and still used by some low cost, non-compliant operators such as taxis, its use for major fleet operators is discouraged due to operational and emissions issues. The new generation technology is typically EPA approved for emissions, CSA and/or UL certified for safety, and meets the operational (reliability, performance, emissions, regulatory compliance) requirements of today’s commercial fleet user.