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FUELS

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DIESEL

Diesel fuel is a byproduct composed of distillates from petroleum refining. Compared to gasoline, diesel has a higher specific gravity, higher boiling point, and higher energy content. It is heavier and oilier than gasoline, and evaporates more slowly. There are different grades of diesel fuel used in different applications, from high-powered locomotives to highway trucks and buses and home heating oil. Diesel is also referred to as "distillate fuel oil."

Diesel engines are internal combustion engines that are designed to compress the fuel to a high temperature, at which point it ignites and completes an engine stroke. Where gasoline requires a spark to ignite, the diesel engine and fuel are efficiently designed to generate ignition without a spark. This is due in part to the higher energy content of diesel fuel. As a benefit of these characteristics, diesel engines produce higher torque (force capable of rotating the axle) and are more fuel efficient than gasoline engines. Heavy-duty vehicles like trucks, buses and locomotives that move heavy weight use diesel engines because they can meet their power needs.

Diesel engines are becoming cleaner as government and industry efforts work together to develop cleaner engines and emissions control technologies. To learn more about these efforts, follow the links below: