Fuel price glossary

EIA: U.S. Energy Information Administration, the federal statistics agency that publishes the weekly retail fuel price survey used on this site.
On-highway diesel: Ultra-low-sulfur diesel sold for road vehicles, taxed for highway use. EIA’s weekly figure is the benchmark for most trucking fuel surcharges.
ULSD: Ultra-low-sulfur diesel: no more than 15 parts per million of sulfur. Standard for U.S. on-highway use.
Regular gasoline: Gasoline with an octane rating of about 87. EIA reports “all formulations” (conventional and reformulated combined).
Midgrade gasoline: Gasoline with an octane rating of about 89.
Premium gasoline: Gasoline with an octane rating of about 91 or higher.
Octane rating: A measure of gasoline’s resistance to engine knock. U.S. pumps show the average of research and motor octane.
PADD: Petroleum Administration for Defense District: one of five U.S. regions used by EIA to report fuel data.
Spot price: The price for prompt delivery of a fuel at a trading hub, such as New York Harbor or the U.S. Gulf Coast. Excludes taxes and retail costs.
New York Harbor: The main East Coast trading hub for gasoline, diesel and heating oil.
U.S. Gulf Coast: The largest U.S. refining center and the benchmark location for jet fuel spot prices.
Brent: The international crude oil benchmark, priced in dollars per barrel.
WTI: West Texas Intermediate, the U.S. crude oil benchmark, priced at Cushing, Oklahoma.
Barrel: 42 U.S. gallons.
Crack spread: The difference between a refined product’s price and its crude oil cost; a proxy for refining margins.
Distillates: Middle-of-the-barrel fuels: diesel, heating oil and jet fuel.
Heating oil: No. 2 fuel oil used for home heating, chemically close to diesel; it competes for the same supply in winter.
Kerosene-type jet fuel: The fuel used by commercial jets (Jet A); its Gulf Coast spot price is the U.S. benchmark.
Reformulated gasoline (RFG): Cleaner-burning gasoline required in some metropolitan areas.
CARB fuel: Gasoline and diesel meeting California Air Resources Board specifications.
RVP: Reid vapor pressure; a measure of gasoline volatility, limited more strictly in summer.
Excise tax: A per-gallon tax: federal 18.4¢ on gasoline and 24.4¢ on diesel, plus state taxes.
Rack price: The wholesale price at a fuel terminal, before transport to the station.
Retail margin: What stations earn between their fuel cost and the pump price.
Fuel surcharge: A charge carriers add to freight rates to recover fuel costs, often indexed to EIA diesel.
Peg price: In a trucking surcharge, the diesel price already assumed in the base rate.
Cost per mile: Fuel price divided by miles per gallon.
Week over week: The change from the previous weekly survey.
Year over year: The change from the same week a year earlier.
Rockets and feathers: The observation that retail fuel prices tend to rise quickly when wholesale costs jump but fall more slowly when they drop.
SHOPP: State Heating Oil and Propane Program: EIA and state energy offices’ weekly survey of residential heating oil and propane prices, October through March.
STEO: Short-Term Energy Outlook: EIA’s monthly official forecast of energy prices, supply and demand for the next one to two years.
WPSR: Weekly Petroleum Status Report: EIA’s Wednesday report of U.S. crude and fuel inventories, refinery runs and demand.
Btu: British thermal unit, a measure of heat. Heating oil holds about 138,500 Btu per gallon, propane about 91,452 and a kWh of electricity 3,412.
Heat pump COP: Coefficient of performance: units of heat delivered per unit of electricity used. A seasonal COP of 2.5 means 2.5 times as much heat as resistance heating.
Pre-buy: A heating fuel contract that fixes the price for a set number of gallons, usually paid before winter.
GGE: Gasoline gallon equivalent: the amount of a fuel with the same energy as one gallon of gasoline. Used to compare alternative fuel prices.
DGE: Diesel gallon equivalent: the amount of a fuel with the same energy as one gallon of diesel.
E15: Gasoline with up to 15% ethanol, approved by EPA for 2001-and-newer cars and light trucks.
E85: A high-ethanol blend (51–83% ethanol) for flex-fuel vehicles.
CNG: Compressed natural gas, sold per gasoline gallon equivalent.
LNG: Liquefied natural gas, used in heavy trucks and sold per diesel gallon equivalent.
Propane autogas: Propane used as a vehicle fuel.
B20: A blend of 20% biodiesel and 80% petroleum diesel.
Renewable diesel: Diesel made from fats and oils that is chemically similar to petroleum diesel and used as a drop-in replacement.
Dyed diesel: Off-road diesel colored red to show that highway taxes were not paid; illegal in on-road vehicles.
Rack-plus pricing: Fuel priced at a terminal’s posted rack price plus a fixed adder for delivery and margin.
Fuel surcharge table: A carrier’s published schedule mapping a weekly fuel price to a surcharge percentage or per-mile amount.
LIHEAP: Low Income Home Energy Assistance Program, the federal program that helps eligible households pay heating and cooling bills.