Gas oil is a specific type of fuel that originates from crude oil, undergoing a refining process that separates various components based on their boiling points. It is a middle distillate, meaning it falls between lighter products like gasoline and heavier ones like fuel oil. This fuel serves a variety of purposes, primarily in heating applications and powering certain engines, making it a versatile energy source across different sectors.
Defining Characteristics
Gas oil is a clear, light-colored liquid, though its hue can vary depending on its composition and any additives. Its density, higher than gasoline but lower than heavy fuel oils, ranging from 0.82 to 0.86 grams per milliliter at 15 degrees Celsius. This density influences its energy content and how it handles in fuel systems.
The viscosity of gas oil is less viscous than heavier oils, allowing it to flow more readily through pipes and filters, but thicker than gasoline. Its flash point is above 55 degrees Celsius, making it safer to handle and store compared to more volatile fuels. These physical properties are carefully controlled during refining to ensure the fuel meets performance and safety standards for its intended applications.
Primary Uses
Gas oil finds use as a heating fuel, particularly in residential, commercial, and industrial boilers. Its consistent burning properties and energy density make it an efficient choice for generating heat. This application often involves bulk delivery to storage tanks.
Beyond heating, gas oil is a fuel for various engines in off-road or marine environments. It powers agricultural machinery, construction equipment, and certain generators. Marine vessels rely on gas oil for propulsion. The specific use often dictates how the fuel is classified and taxed, leading to distinct forms available in the market.
Different Forms and Their Purposes
Gas oil is not a single, undifferentiated product but rather comes in different forms, primarily distinguished by their intended use and the associated taxation. One distinction is between “red diesel” and “white diesel.” Red diesel, also known as marked gas oil, contains a red dye and chemical markers that it is a rebated fuel. This form is legally permitted only for specific off-road uses, such as in agricultural, construction machinery, and for heating purposes.
In contrast, “white diesel,” or road diesel (DERV), is the standard fuel for road vehicles. It does not contain the red dye and is subject to the full rate of fuel duty, reflecting its use on public roads. This differentiation helps enforce tax regulations and ensure that fuels are used for their designated purposes. Other variants of gas oil exist, such as different grades of heating oil designed for specific boiler types or climate conditions.