Quad (unit)

A Sankey diagram using quads.

A quad is a unit of energy equal to 10¹⁵ (a short-scale quadrillion) BTU,^[1] or 1.055 × 10¹⁸ joules (1.055 exajoules or EJ) in SI units.

The unit is used by the U.S. Department of Energy in discussing world and national energy budgets. The global primary energy production in 2004 was 446 quad, equivalent to 471 EJ. ^[2]

Some common types of an energy carrier approximately equal to 1 quad are:

• 8,007,000,000 gallons (US) of gasoline
• 293,071,000,000 kilowatt-hours (kWh)
• 293.07 terawatt-hours (TWh)
• 33.434 gigawatt-years (GWy)
• 36,000,000 tonnes of coal
• 970,434,000,000 cubic feet of natural gas
• 5,996,000,000 UK gallons of diesel oil
• 25,200,000 tonnes of oil
• 252,000,000 tonnes of TNT or five times the energy of the Tsar Bomba nuclear test
• 13.3 tonnes of uranium-235

References

1. "Energy: Glossary". Department of Materials Science and Engineering, University of Illinois Urbana-Champaign. QUAD: an amount of energy equal to 10¹⁵ BTU.
2. Energy Information Administration (2006-07-31). "World Consumption of Primary Energy by Energy Type and Selected Country" (Excel spreadsheet). International Energy Annual 2004. Retrieved 2007-05-12.