The quad is a unit of energy defined as 1 quadrillion (1015) BTU.[1] Quads are used in similar settings as the exajoule (1018 joules) when speaking of world or national energy supply/demand.

Generally, quads refer to primary energy rather than end use energy.

For further reading


  1. APS Physics. (2015). Energy Units [Online]. Available: http://www.aps.org/policy/reports/popa-reports/energy/units.cfm [February 20, 2015].