What you should know about automotive fuels

Every existing product and service consumes some amount of fuel, whether it involves the transportation of manufactured goods or travelling in a bus to get to work.

But how much do we know about the quality of fuel that goes into the vehicles on which we depend? And what is the impact of automotive fuel consumption on our health and the environment?

Many different types of automotive fuels exist worldwide. These include fossil fuel derivatives such as gasoline, diesel, compressed natural gas (CNG) and propane (LPG). The first three are used in our country as automotive fuels.

Alternative fuels include biodiesel, ethanol (which can be used in combination with gasoline) and hydrogen.

Although the majority of the world’s vehicles run on gasoline and diesel, there is a drive (pun intended!) for the advancement of alternative fuels. This is due to a number of factors:

The finite supply of fossil fuels

A need to reduce the environmental impact of emissions

The increasing costs of traditional fuels

The quality and type of automotive fuel affects engine performance, and impacts on our health and environment. Automotive fuels most commonly used in TT, gasoline and diesel, are composed of hundreds of different types of hydrocarbons.

Certain components are carcinogenic or can produce carcinogenic emissions. These include benzene, olefins and other aromatic hydrocarbons. Leaded gasoline, which produces toxic emissions of lead, has been phased out of the local market since April 2004. Sulphur occurs naturally in crude oil and is found in both gasoline and diesel. Upon combustion, sulphur is emitted as sulphur dioxide (SO2) or sulfate particulate matter. Lowering sulphur equates to lower emissions.

Octane is a measure of the resistance of gasoline to auto-ignition. Simply put, octane determines the “anti-knock” quality.

“Knocking” or “pinging” is the sound produced from a running engine when the fuel is detonating instead of burning smoothly.

Vehicles are designed and calibrated for a certain octane level. There are two types of gasoline sold in Trinidad – Super, which has a research octane number (RON) of 92 and Premium, which has a RON of 95. It is important to know the recommended octane number for your vehicle.

The cetane number is a measure of the compression ignition behaviour of diesel. Studies have shown that an increase in the cetane number reduces emissions of nitrous oxides, hydrocarbons and carbon monoxide. Fuel consumption and engine noise are also reduced.

There are two compulsory standards governing the requirements for gasoline and diesel in TT:

TTS 269:2007, Unleaded gasoline for motor vehicles — Specification

TTS 569:2007, Automotive diesel fuel — Specification

These standards were developed with guidance from other national and international regulations such the Worldwide Fuel Charter (WWFC).

These national standards prescribe specific characteristics of the fuel. Characteristics identified for gasoline include RON, sulphur content, lead content, olefins content and benzene content. Characteristics identified for diesel include cetane number, distillation temperature, sulphur content and aromatic hydrocarbon content.

The WWFC was developed to “promote greater understanding of the fuel quality needs of motor vehicle technologies and to harmonise fuel quality worldwide in accordance with engine and vehicle needs.” It puts forward four levels of specifications for both gasoline and diesel, recognising that each country has a different level of development with respect to infrastructure and resources.

Another automotive fuel commonly used in TT is CNG. CNG is made by compressing natural gas, a fossil fuel comprising mainly methane, to less than one per cent of its atmospheric volume. CNG has been in use in TT since 1992 as an automotive fuel. Relative to gasoline and diesel, CNG produces lower emissions of carbon dioxide and hydrocarbons, is burned more efficiently, and has less risk related to operation and spillage. However, distribution networks in TT are limited, engine power is reduced and, ultimately, it is not a renewable resource.

There are many considerations for the type and quality of automotive fuel that you use and it is important to understand the health, environmental and performance impacts. A properly maintained engine can contribute to reducing any negative impacts. Moreover, TTBS is committee to playing a role in ensuring that the welfare of the public and the environment is protected.