Estimating methane releases from natural gas production and transmission in Russia

Methane releases from the RAO Gazprom gas production and transmission facilities in Russia were determined in an extensive measurement program carried out in 1996 and 1997. Subsequently, the measurements were extrapolated to the Russian scale. The results show that methane releases from gas transmission are less than 1% of throughput. Methane loss from gas production in northwestern Siberia appears to be relatively small, generally less than 0.1%. The largest methane emissions result from venting during maintenance and repairs, leaks from valves on transmission lines, and from compressor stations. The measurements show that, in the case of leaks, a limited number of major ones accounts for most of the methane releases. Methane emissions expressed as a percentage of the gas volume produced or transported are (rounded figures): production and processing 0.1%, pipelines 0.2 %, compressor stations 0.7 %, so that the total release by production and transmission in Russia amounts to about 1.0%, i.e. similar to 5.4 x 10(9) m(3)/a (similar to 4 Tg/a). This is consistent with our previous preliminary estimates, indicating that maximum emissions are 1.5-1.8%/a. However, this is generally lower than most other estimates and speculations. (C) 1999 Elsevier Science Ltd. All rights reserved.