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Diesel fuel explained  

What is diesel fuel?

Diesel fuel is the common term for the petroleum distillate fuel oil sold for use in motor vehicles that use the compression ignition engine named for its inventor, German engineer Rudolf Diesel. He patented his original design in 1892.

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One of the fuels that Rudolf Diesel originally considered for his engine was vegetable seed oil, an idea that eventually contributed to biodiesel production and use today.

Diesel fuel is made from crude oil

Diesel fuel is refined from crude oil at petroleum refineries. U.S. petroleum refineries produce an average of 11 to 12 gallons of diesel fuel from each 42-gallon (U.S.) barrel of crude oil.

Before 2006, most diesel fuel sold in the United States contained high quantities of sulfur. Sulfur in diesel fuel produces air pollution emissions that are harmful to human health. In 2006, the U.S. Environmental Protection Agency issued requirements to reduce the sulfur content of diesel fuel sold for use in the United States. The requirements were phased in over time, beginning with diesel fuel sold for vehicles used on roadways and eventually including all non-road diesel fuel. Diesel fuel now sold in the United States for on-highway use is ultra-low sulfur diesel (ULSD), which has a sulfur content of 15 parts per million or less. Most diesel fuel sold for off-highway (or non-road) use is also ULSD.

A photograph of a large freight truck that has a diesel engine

Freight truck with diesel engine

Source: Stock photography (copyrighted)

A graphic illustration of a barrel to show the different products produced from a barrel of crude oil in 2018: other products 7 gallons, liquified petroleum gases 2 gallons, jet fuel 4 gallons, heavy fuel oil (residual) 1 gallon, other distillates (heating oil) 1 gallon, diesel 11 gallons, and gasoline 19 gallons.

Click to enlarge

Diesel fuel has many uses

Most freight and delivery trucks as well as trains, buses, boats, and farm, construction, and military vehicles have diesel engines. Some small trucks and cars also have diesel engines. Diesel fuel is also used in diesel engine generators to generate electricity, such as in remote villages in Alaska, among other locations around the world. Many industrial facilities, large buildings, institutional facilities, hospitals, and electric utilities have diesel generators for backup and emergency power supply.

In 2019, distillate fuel (essentially diesel fuel) consumption by the U.S. transportation sector was about 47.2 billion gallons (1.1 billion barrels). This amount accounted for 15% of total U.S. petroleum consumption and, on an energy content basis, for about 23% of total energy consumption by the transportation sector.

Last updated: June 12, 2020