Emissions and discharges from the oil and gas industry in 2009
17/06/2010 Emissions to air from the petroleum industry declined in 2009. This applies to carbon dioxide (CO2), nitrogen oxide (NOx) and volatile hydrocarbons, according to the operating companies’ annual emissions reporting. These reports are made in parallel to the Norwegian Climate and Pollution Agency (Klif), the Norwegian Petroleum Directorate (NPD) and the Norwegian Oil Industry Association (OLF) in EnvironmentWeb – a joint database for the authorities and the oil and gas industry.
Emissions to air
Carbon dioxide (CO2)
In 2009, the petroleum activities emitted 12.4 million tonnes of CO2, a decline from 13.8 million tonnes in 2008. The main reason for the decline is that the Snøhvit facility outside Hammerfest is now operating normally. In addition, a new and more precise method of calculating emissions from flaring has been implemented.
According to Statistics Norway (SSB) and Klif, Norwegian emissions of greenhouse gases amounted to 50.8 million tonnes of CO2 equivalents in 2009, a decline of 5.4 per cent from 2008. This means that the oil and gas industry was responsible for 26 per cent of the national CO2 emissions in 2009, which represents a slight decline from 26.6 per cent in the previous year.
Nitrogen oxide (NOx)
In 2009, total NOx emissions from the petroleum activities amounted to 49 804 tonnes, which is a slight reduction from the 50 882 tonnes emitted in 2008. There has been relatively little change in the total emissions of NOx in recent years.
According to SSB and Klif, total Norwegian emissions of NOx in 2009 amounted to 167 500 tonnes, a decline of 4 per cent compared with 2008. The oil and gas industry accounted for 29.7 per cent of the national emissions.
Volatile organic compounds (nmVOC)
The oil and gas industry’s emissions of nmVOC totalled 45 503 tonnes in 2009, a reduction of 9.8 per cent from 2008, when the emissions amounted to 50 455 tonnes. Since 2001, emissions of nmVOC from the oil and gas activities have been reduced by more than 80 per cent. These significant emission reductions have been achieved as a consequence of installing facilities to remove and recover oil vapour on storage vessels and shuttle tankers.
According to SSB and Klif, total Norwegian emissions of nmVOC in 2009 amounted to 160 600 tonnes. The oil and gas industry was responsible for 28.2 per cent of the national emissions. The measures implemented offshore have now led to lower national emissions of nmVOC than Norway’s 2010 commitment under the Gothenburg protocol.
Production discharges to sea
Production of oil is normally accompanied by water. The amount of water increases as the fields age and the reservoirs are depleted. This water is either reinjected into the reservoir, or cleaned and discharged. Discharges in 2009 totalled 135 million cubic metres, a reduction of about 10 per cent compared with 2008.
Oil in produced water
The authorities require the lowest possible oil content in the water that is discharged, and it must not exceed 30 milligrams of dispersed oil per litre of water. The average concentration in 2009 was 11 milligrams per litre. This is a small increase from 2008 when the average concentration was 10.5 milligrams per litre. A total of 1500 tonnes of oil was discharged to sea with produced water in 2009.
The operating companies on the Norwegian Shelf regularly conduct environmental monitoring. This monitoring has not proven any significant effects resulting from these discharges. The oil and gas industry continues to contribute to further research to refine the methods used to monitor the environment.
Discharge of chemicals
Chemicals are classified in accordance with Klif’s system of green, yellow, red or black categories. Chemicals in the green category do not entail harm or disadvantages to the marine environment; chemicals in the yellow category are normally not defined as environmentally hazardous; while chemicals in the red and black categories are prioritised for substitution and are subject to strict regulation. These chemicals can only be discharged if necessary due to weighty safety or technical reasons.
The total volume of chemicals used in 2009 was 480 000 tonnes. 174 000 tonnes of this amount were discharged, 99.9 per cent of which were in the green or yellow categories. The remaining volumes were injected (74 000 tonnes), re-used or handled as waste. Chemical consumption and discharge has increased somewhat compared with 2008, while the injected volume is somewhat lower.
After the target of zero discharges of oil and environmentally hazardous substances was introduced in 1997, discharges of chemicals in the black category have been reduced from 228 tonnes to barely one tonne in 2009. Discharges of chemicals in the red category have been reduced from 3933 tonnes to 32 tonnes in the same period. More than 99 per cent of all environmentally hazardous chemicals have been removed during the course of the past ten years.
These numbers confirm that the operators’ work to reduce discharges of environmentally hazardous chemicals on the Norwegian Shelf has yielded results. Storting White Paper No. 26 (2006-2007) says that the zero discharge target for added chemicals has been achieved. Nevertheless, the work to reduce discharges continues, in part through investigation of the possibility of injecting produced water and drill cuttings. At the same time, the work to substitute added chemicals continues as before.
Accidental discharges to sea
In 2009, there were 147 accidental discharges of oil; four of which were larger than one cubic metre. The total volume of oil from accidental discharges in 2009 was 114 cubic metres. The trend over the last six years shows a weak increase, while there was a marked decline prior to 2002.
There were 162 accidental discharges of chemicals in 2009; an increase compared with recent years. The total volume, 13 052 cubic metres, was considerably higher in 2009 compared with previous years. One discharge, a leak of slurrified cuttings from an injection well on the Veslefrikk field, accounted for as much as 97 per cent of this volume. The volume of the discharge has been estimated at 48.5 cubic metres of oil and 12 619 cubic metres of chemicals. 94 per cent of these chemicals are in the green and yellow categories, while 348 cubic metres are in the red category and 1.6 cubic metres are in the black category. The discharge volumes have been calculated by assuming that everything injected into this specific well may have leaked out. The leak has probably been present since 1997, but the entire discharge volume has been reported in 2009. This in accordance with normal practices for accidental discharges.
The authorities and the oil industry agree that the number of accidental discharges has stabilised at a level that is too high. The oil companies are working to reduce the number of accidental discharges.
- Klif: Hanne Marie Øren,
head of petroleum activities section
Tel. +47 22 57 37 82, mobile: +47 920 26 650,
- NPD: Arne Holhjem,
director, environment and energy
Tel. +47 51 87 61 00,
- OLF: Tore Killingland,
director, strategy and environment
Tel. +47 51 84 65 93, mobile: +47 917 52 604,