According to US Energy’s Weekly Fuel Price Report for the week ending August 19th, the Thai consumer currently pays an estimated 104.104 Thai Baht ($2.79 US) per gallon of diesel while a dual fuel gallon consisting of approximately 65% natural gas/35% diesel, would cost an estimated 57.39 Thai Baht ($1.53 US).

GM has been working closely with the Thai government on a number of alternative fuel initiatives, including CNG conversion technology, so we’re proud to be leading the Thai market in equipping our vehicles with CNG conversion capabilities. With the sustained high prices of fuel, this option will make our one-ton Chevrolet Colorado pickup even more popular with Thai consumers, by offering a certified safe and economical fuel conversion system.

—William Botwick, President of GM’s Southeast Asia Operations and President of General Motors Thailand

HFS systems start the engine with diesel fuel and then inject an increasing amount of natural gas—up to 80%—cutting back on the diesel as the engine speed and load increases. Engine modifications are not required, and the company claims that vehicles retain the diesel engine qualities of performance, torque, power, and efficiency. When operating with natural gas, the system reduces NO_x emissions by at least 30% and PM emissions by 80–90%.

The system consists of a set of parts that can be installed on most medium- and heavy-duty diesel engines within a day by a trained technician. Components include:

• The ECU programmed to meter a precise mixture of natural gas and diesel in response to engine speed, load, temperature and other operating conditions;

• A gas regulation system that maintains a smooth fuel supply under all conditions;

• A gas injection system that allows precise metering under rapidly changing engine conditions; and

• Sensors, wiring harnesses, and all other parts.

Resources:

• Hybrid Fuel System Technology overview