Petroleum refiners rely heavily on refining byproducts as energy sources. These include refinery gas (byproduct of distillation, cracking, and other processes), petroleum coke, and other oil byproducts. About 6% of energy consumed by the industry for heat and power is provided by byproduct fuels. [MECS 1994] About 51% of the total energy used by refineries is petroleum feedstocks used to produce non-fuel products. [MECS 1998]

Energy Consumption by Fuel – 1998 (NAICS 324 Petroleum & Coal Products)
(trillion Btu)

Source: MECS 1998

* Losses incurred during the generation and transmission of electricity
** Includes refinery gas, LPG, coal, coke, and other refinery products