Gas supply chain
There are a number of players in the journey to your premises.
Main segments of the gas supply chain
Gas producers extract gas from both off-shore and on-shore gas fields and process it to remove impurities and produce natural gas.
Transmission network service providers transport bulk gas in high pressure gas transmission lines.
Distributors deliver gas to the majority of end customers. They are also responsible for metering.
Retailers provide billing services to end customers.
Source: Energy Efficiency Exchange (EEX)
Units of Measurement for Gas
Gas consumption is calculated in joules.
The following terms are used for multiples of this unit:
| MJ | megajoule | 1 million joules |
| GJ | gigajoule | 1,000 megajoules |
Your gas account will show your gas consumption in MJs.
Gas Meters
There are 2 types of gas meters.
Metric gas meter
Metric gas meter / Digital gas meter
Metric gas meters measure usage in cubic metres. Either ‘cubic metres’ or ‘m³’ will be marked next to the display window.
The black and white numbers are read from left to right. Any red numbers are ignored.
Imperial gas meter
Imperial gas meter / Dial gas meter
Imperial gas meters measure usage in cubic feet, which will be displayed on the meter’s clock face. This will then be converted to cubic metres.
1 cubic metre = 35.3 cubic feet
These meters have clock faces and dials, with hands rotating in different directions. They are read left to right by taking the lower number if the hand is between two numbers (except if between 0 and 9, which would be recorded as a 9).
Calculating your usage
To calculate your gas charges, your retailer uses a Gas Conversion Factor to convert gas from the units on your meter into the units on which you are billed (megajoules, MJ). This calculation uses figures from your distributor, who is responsible for the gas pipes and meters in your area, and takes into consideration the factors that affect gas (including cubic metres, plus changes in gas pressure and outside temperature).