JODI-Gas FAQ / What are data measurement units?
- Yui Torikata / IEF
Join Date:May 2011 Posted by Yui Torikata/ IEF / 28.05.2014 09:14The JODI-Gas Questionnaire asks countries to report data both in physical and energy units. Therefore, data is available in million m3 (at 15OC. 760mm hg) and terajoules, as well as in 1000 metric tons for LNG trades.
In natural gas statistics more so than in statistics for other energy products, the choice of measurement unit and the conditions under which the measurements are taken have significant importance. This arises from the fact that the most appropriate unit can differ depending on the area of activity that is being analysed. For example, an end-user of natural gas will normally be interested in the value of the gas on an energy basis (as it is purchased for its heating value); an LNG tanker will normally measure its cargo in tons; gas travelling by pipeline will often be measured on a volumetric basis.
These differing units can present challenges to the statistician when trying to present comparable data. In order to accurately convert among the units, the statistician must know:
- The temperature and pressure at which the gas volume was recorded (when measured on a volumetric basis);
- The calorific value of the gas.
However, this information is not readily available for all countries at this stage, as some countries do not report data in all three units. Also, only APEC collects LNG trade data in 1000 metric tons.