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Deisel

[edit] Petroleum diesel

A modern diesel pumpPetroleum diesel, or petrodiesel[1] is produced from petroleum and is a hydrocarbon mixture, obtained in the fractional distillation of crude oil between 200 °C and 350 °C at atmospheric pressure.

The density of petroleum diesel is about 850 grams per litre whereas petrol (gasoline) has a density of about 720 g/L, about 15% less. When burnt, diesel typically releases about 40.9 megajoules (MJ) per litre, whereas gasoline releases 34.8 MJ/L, about 15% less.[citation needed] Diesel is generally simpler to refine from petroleum than gasoline. The price of diesel traditionally rises during colder months as demand for heating oil rises, which is refined in much the same way. Due to its higher level of pollutants, diesel must undergo additional filtration[citation needed] which contributes to a sometimes higher cost. In many parts of the United States and throughout the UK, diesel may be higher priced than petrol.[2] Reasons for higher priced diesel include the shutdown of some refineries in the Gulf of Mexico, diversion of mass refining capacity to gasoline production, and a recent transfer to ultra-low sulfur diesel (ULSD), which causes infrastructural complications.[3]

Diesel-powered cars generally have a better fuel economy than equivalent gasoline engines and produce less greenhouse gas pollution. Their greater economy is due to the higher energy per-litre content of diesel fuel and the intrinsic efficiency of the diesel engine. While petrodiesel's 15% higher density results in 15% higher greenhouse gas emissions per litre compared to gasoline,[4] the 20–40% better fuel economy achieved by modern diesel-engined automobiles offsets the higher-per-liter emissions of greenhouse gases, and produces 10-20 percent less GHG emissions than comparable gasoline vehicles.[5][6][7] However, the EPA carbon footprint estimates do not include the carbon cost of vehicle manufacture, nor the carbon cost of filtering particulates,...