An assessment of compressed natural gas vehicle performance in winter
Are you looking to add compressed natural gas (CNG) vehicles to your fleet, but aren’t sure if this type of fuel performs as well during winter in Quebec?
In fact, vehicles running on compressed natural gas are just as efficient as diesel trucks during the winter. All you have to do is learn about the factors to watch out for and solutions to prevent any potential problems.
Read this article to learn more!
Adjustments to make on CNG trucks operating in wintertime
In order for a heavy-duty CNG vehicle to perform adequately during winter, one must first determine the temperatures the vehicle might operate in.
Specifically, you need to know whether the CNG vehicle will operate in “normal” (approximately -20°C) or “arctic” (-32°C to -54°C) temperatures. The colder the climate of the region being served, the more modifications to the vehicle will be required to prepare it for winter.
Here are some of the possible modifications for CNG vehicles.
Electrical system maintenance
Vehicle battery efficiency tends to decrease in cold weather. To maintain an adequate starting speed to start the engine, you will either need to use battery heaters or increase battery capacity from the start.
Air intake system optimization
The air intake of CNG trucks operating at temperatures below 0°C must be located in the truck engine so that hot air from the truck can be drawn in to assist the combustion process.
In the case where the air intake system (including the air filter) is located outside the engine compartment, a method of transferring exhaust heat to the air intake system will have to be developed.
The importance of using low-viscosity oil in winter
The viscosity of the engine oil changes in cold weather, which reduces the starting speed and requires more battery power to start the vehicle. The vehicle’s CNG performance is therefore at risk of being severely impaired.
However, this problem can be easily solved by using a low-viscosity oil. For example, it is recommended to choose an oil with viscosity numbers of 10W40 (normal winter temperatures) or 0W30 (arctic temperatures). This will make starting the truck much easier and ensure that the engine is well lubricated.
Problems most likely to affect CNG vehicle performance in cold weather conditions
In general, operators of heavy CNG vehicles encounter very few problems with their trucks when driving in winter. However, careful attention must be paid to the quality of the fuel used to power CNG vehicles. Truck performance can be affected by moisture levels, heavy hydrocarbons and the sulphur content of the fuel.
The lower the outside temperature, the drier the natural gas should be. For example, at natural gas compressor stations, natural gas dryers must operate efficiently to prevent moisture ingress.
CNG trucks: excellent performance in both summer and winter
In summary, maintaining satisfactory CNG truck performance in cold weather requires some modifications to the systems with regard to the minimum temperatures they may be exposed to. Attention must also be paid to the quality of the fuel, since the vehicle will not operate properly if moisture or other elements affect the fuel.
EBI was one of the first companies to put its CNG trucks to the test in the Quebec winter. The conclusions of this experiment proved that these vehicles remain efficient even in temperatures as low as -20°C. For more information on the strategy to adopt to promote the use of compressed natural gas, contact us today!