Environment Report 2016

ENVIRONMENT REPORT 2016

Gas Venting Gas venting releases natural gas associated with production directly into the atmosphere without ignition. Venting is a safety mechanism to release gas pressure when a safe level may be exceeded. Venting is also subject to consent under the Petroleum Act 1998 through application to the OGA. Applications undergo a detailed review and those operators that vent over five tonnes per day will be reviewed annually. All venting activity must be reported in EEMS. Almost 41,000 tonnes of gas were vented on the UKCS last year, a 10 per cent increase on 2014 in line with the percentage rise in production. Just under 558,000 tonnes of CO 2 e were emitted from venting on the UKCS in 2015, which is approximately a sixth of that released through gas flaring. Gas venting is reported under EEMS as either operation, maintenance, emergency or gross. Gross is reported when a breakdown is not available and could therefore be any of the other categories; the majority falls into this category, as shown in Figure 13. When excluding gross, operational (equivalent to routine for flaring) accounts for the greatest proportion of emissions in each year.

Figure 13: Breakdown of Gas Venting by Source

Gross

Emergency

Maintenance

Operational

50,000

45,000

40,000

35,000

30,000

25,000

20,000

15,000 Total Gas Vented (Tonnes)

10,000

5,000

0

2010

2011

2012

2013

2014

2015

Source: EEMS July 2016

The largest proportion of gas vented between 2010 and 2015 was in the NNS (41 per cent). This is likely due to the presence of older and larger integrated platforms in this area. Gas venting is also associated with natural gas production and so the gas-producing SNS region has the second largest percentage of vented emissions (31 per cent). Installations less than ten years old (12.5 per cent of reporting platforms) are the smallest contributors to gas venting on the UKCS (just over 2.5 per cent) between 2010 and 2015. This indicates that this activity is being minimised through design of these installations and, in turn, the new developments in the W o S mean this area vents smaller proportions of gas at 2.3 per cent.

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