Natural gas: Flammable gas, consisting largely of methane and other hydrocarbons, occurring naturally underground (often in association with petroleum) and used as fuel.
Gas reinjection: The reinjection of natural gas into an underground reservoir, typically one already containing both natural gas and crude oil, in order to increase the pressure within the reservoir and thus induce the flow of crude oil or else sequester gas that cannot be exported.
Gas flaring: burning off gas, as waste or pressure relief.
Transformation: Energy transformation refers to the conversion of primary energy (see above) to more useful forms of energy. It includes activities such as electricity generation, oil refining and other transformation (including coal used for steel manufacturing) as well as losses.
Cogeneration: the generation of electricity and useful heat jointly, especially the utilization of the steam left over from electricity generation for heating.
Non-energy use: primary energy used for purposes other than combustion, e.g. natural gas used as chemical feedstock in the production of methanol and ammonia/urea.
Gas Supply is calculated as the difference between the total amount of gas produced and the amount of gas flared, reinjected, extracted as LPG, and losses and own use during gas production.
Net Gas Production is calculated as the difference between the total amount of gas produced and the amount of gas flared, reinjected, extracted as LPG, and losses and own use during gas production.
Gas Consumption and Non-Energy Use data are not available before 1990.
Changes to data collection/processing
The Ministry has improved the methodology for producing gas production and consumption statistics, as well as updating some historical data. This has resulted in changes to previously-published data.