Revised model for calculation of NMVOC emissions from solvent and other product use

High emissions from solvent use

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Norway has considerably higher emissions of volatile organic compounds from the use of solvents and other products per inhabitant than for instance Sweden and the United Kingdom. A high level of construction activity and renovation makes the emissions from the use of paint and varnish particularly high.

Volatile organic compounds except methane (NMVOC) can react with NO X gases to create ground-level ozone. While ozone is a required gas in the stratosphere, it is also a poisonous gas that damages human health, vegetation and buildings at ground level. Based on these properties it is an objective to reduce emissions of NMVOC.

The overall Norwegian emissions of NMVOC have been reduced in the past few years, although the emissions are still close to two per cent above the target set from the endorsement of the Gothenburg protocol (see text box). In 2007, 199 000 tonnes of NMVOC were emitted in Norway. The most dominant sources were process emissions from the oil and gas extraction (37 per cent in 2007) and emissions from the use of solvents and other products (25 per cent in 2007). A decree from the Norwegian Pollution Control Authority that loading and unloading of crude oil on the continental shelf should be done by using technology that limits the NMVOC emissions, is the most important reason for the decrease in the total emissions since 2001 (Statistics Norway 2009a).

The emissions of NMVOC from the use of solvents and other products are considerably higher per inhabitant in Norway than in Sweden and the United Kingdom (see table). Both of these countries are natural comparisons, as they use comparable calculation methods for emissions of NMVOC from solvent and other product use, and they also have a similar level of costs and living standards. Note that for international comparison, numbers from 2005 are used.

Emissions of NMVOC, source distributed. 2005
Source Norway Sweden United Kingdom
Total
Kilotonnnes 51.9 70.1  405.2
Kilos per inhabitant 11.2 7.8 6.7
Use of paint and varnish
Kilotonnnes 11.4 16.7  117.3
Kilos per inhabitant 2.5 1.8 1.9
Degreasers and dry cleaning
Kilotonnnes 0.6 0.1 30.8
Kilos per inhabitant 0.1 0.0 0.5
Production and processing of chemicals
Kilotonnnes 0.9 0.8 14.8
Kilos per employee in the chemical industry 66.0 21.4 1 69.5
Other
Kilotonnnes 39.0 52.5  242.3
Kilos per inhabitant 8.4 5.8 4.0
Of which ensilage
Kilotonnes 3.6 : :
Kilotonnes per decare grassland for harvest and grazing 0.6 : :
1   The number of employees in the chemical industry is from 2007.
Source:  BERR (2008), CEIP (2008), UN (2008), Statistics Sweden (2009), Statistics Norway (2009b).

Norwegians love redecorating

Statistics Norway has calculated the emissions from the use of paint and varnish to be much higher in Norway than what is reported in Sweden and the United Kingdom. This source does not only contain emissions from paint and varnish used in private households, but also emissions from the use of paint and varnish in industrial sectors. The difference in emissions between countries may thus be due to different use of paint and varnish in the industries. In Norway approximately three quarters of these emissions were due to the use of decorative paint, i.e. from paint and varnish used in private households and office buildings. The remaining emissions were due to use in various industrial sectors. This yielded an average emission of 1.8 kilos per inhabitant from decorative paint application in 2005.

The high emissions from the use of paint and varnish may be due to the fact that Norwegians are “world champions in redecorating” (see the figurex). The winter season is long, and we spend much of our spare time at home. In 2002, paint and various materials for redecoration and repair of residences for more than NOK 13 billion were sold in Norway (Statistics Norway 2002a). In 2000 six per cent of all Norwegians stated that they occupied their spare time doing such activities, and they used in average two hours and sixteen minutes per day doing so, according to Statistics Norway’s time expenditure survey (Statistics Norway 2002b).

NMVOC- challenges and system of agreements

NMVOC (Non-Methane Volatile Organic Compounds) are volatile organic compounds (except methane) with a vapour pressure of 0.01 kPa or more at 20 degrees Celsius, or with equivalently volatility at area of use.

NMVOC is an ozone precursor. This means that the substance reacts with NO X gases in the presence of sunlight, and ozone is created. While ozone is an important gas in the atmosphere, where it contributes to reduce the hazardous effects of solar radiation, it is a poisonous substance at ground level, where it damages the health of humans and animals, harms vegetation and buildings.

Due to the harmful effects of NMVOC, Norway is obligated to reduce the emissions of NMVOC to 195 000 tonnes per year from 2010. This is a consequence of Norway’s endorsement of the Gothenburg protocol, one of the protocols related to the convention of long-range, transboundary air pollution (LRTAP). Norway reports the emissions of NMVOC to the LRTAP each year.

In addition to being an ozone precursor, NMVOC is also an indirect source of CO 2 emissions. This is because the substances oxidize to CO 2 after some time in the atmosphere. Emissions of NMVOC are thus also reported to the United Nations as part of the obligations related to the Kyoto protocol.


The numbers concerning repair and maintenance of residences are gathered from the expenditure surveys is each country (Office for National Statistics 2005; Statistics Norway 2008; Statistics Sweden 2008). These are sample surveys, and they yield only an indication of the expenditure in each country.

Indeed, the building costs in Norway are among the highest in Europe, and this entails that building materials, including paint and varnish, have a higher level of cost than other European countries (Statistics Norway 2009c). On the other hand, the European spending power survey of 2007 (Statistics Norway 2009c) shows that Sweden and the United Kingdom also are among the countries with the highest building costs. The comparison between the countries is thus relevant.

Cold and wet summers

In the category “Other” in the table emissions from sources that do not fit into any other category are placed. This may concern emissions from private households and from products and sectors that do not fit naturally into any other part of the inventory, such as ensilage means (substances used for the conservation of grass into cattle feed) used in the agricultural sector. In this category the Norwegian emissions are particularly high compared to the emissions in Sweden and the United Kingdom.

The emissions from formic acid used in the production of silage was in 2005 responsible for about seven per cent of the NMVOC emissions, and the substance had the fourth largest emission in Norway, with about 0.8 kilos per inhabitant. As a comparison, formic acid is not even among the 50 most common NMVOCs in the United Kingdom (UK Emissions Inventory Team, AEA 2008). The reason for this discrepancy may be differences in agricultural procedures in Norway due to climatic differences between countries.

New model for calculation of NMVOC emissions from solvent and other product use

In 2008 Statistics Norway developed a new side model for calculating emissions of NMVOC from solvent and other product use ( read the report here ). In connection with this project, the emissions have been studied in detail to find the dominant sources of emissions.

The emissions are calculated for each substance according to the formula

Consumption = Import + Production - Export

Emissions = Consumption X Emission factor

The total emissions are then calculated as the sum of the emissions of each substance. In the previous model, emissions of NMVOC were calculated based on import, production and export of solvent-containing products. This method made assumptions relating to both the solvent content of each product and emission factors. The new model utilizes data from the Norwegian Product Register. The information from the Product Register contains information about quantity and area of use for substances that are imported to, produced in or exported from Norway in quantities above 100 kilos per year. The information is present at the substance level, which means that no assumptions about solvent content have to be made. Substances that are volatile organic compounds have been identified, and constitute the data material for the calculations

The Norwegian Product register has developed over time, and covers more and more products and substances. Data from the Product Register was deemed to be of sufficient quality from the year 2005, and adjusted emission figures from the previous solvent model has been used for the years 1989-2004.

The calculation methods for emissions of NMVOC from other sources, such as the loading and unloading of crude oil and the use of petrol have not been changed. The transition to a new model for calculating emissions of NMVOC from solvent and other product use has lead to that this source now is responsible for a larger proportion of the emissions of NMVOC. In May 2008 preliminary emission figures were published, and in these calculations the emissions from the previous solvent model was included. In these figures, the emissions from solvent and other product use were responsible for 22.1 per cent of the total NMVOC emissions. When the new model was used for the more final figures published in February 2009, solvent and other product use stood for 24.5 per cent for the same year.

The use of ensilage means is also high in Norway compared to Sweden and Denmark, even though Norway uses a smaller agricultural area for production of animal feed. The large emissions from ensilage in Norway are thus not due to the amount of animal feed produced, but rather the structure of the production of animal feed. While the winter feed in Norway consist almost a hundred per cent of ensiled grass, the Danish winter feed consists of only about one third of grass conserved in this manner. In addition to this, the conditions for ensilage are difficult in Norway. The water content of the grass is higher than in our neighboring countries, while the sugar content is lower in the types of grass used in Norwegian agriculture (Selmer-Olsen 2006). Due to these circumstances, good ensilage is important in Norway, and the use of ensilage means is high. Another factor is that the Norwegian summers are shorter and wetter, and the use of outdoor feeding is shorter in Norway than in Sweden and Denmark.


See also theme page about The climate and air pollution .


References

BERR (2008) Small and Medium - sized Enterprise ( SME ) Statistics for the UK and Regions 2007 . From: http://stats.berr.gov.uk/UKSA/ed/sa20080730.htm

CEIP (2008): Officially reported emission data . From: http://www.ceip.at/emission-data-webdab/emission-as-reported-by-parties/

UN (2008): 2005 Demographic yearbook . Fifty - seventh issue . United Nations, Department of Economic and Social Affairs, ST/ESA//STAT/SER.R/36 From: http://unstats.un.org/unsd/demographic/products/dyb/dybsets/2005%20DYB.pdf

Office for National Statistics (2005): Family spending . A report on the 2004 - 05 expenditure and food survey . From: www.statistics.gov.uk

Selmer-Olsen, I. (2006): Bruk av ensileringsmiddel til å styre surfringa i både retning og omfang . (In Norwegian).In: Plantemøtet østlandet 2006- Plantevern, jord og miljø, økologisk jordbruk, korn, potet, grovfor, kulturlandskap, grønnsaker (Red. Kristoffersen, A.ø.) Bioforsk, page 174-175.

Statistics Norway (2002a): Industrial activities , wholesale and retail trade . Table 05076 in the StatBank. From: http://statbank.ssb.no//statistikkbanken/default_fr.asp?PLanguage=1

Statistics Norway (2002b): Time use survey 2000 . From: http://www.ssb.no/english/subjects/00/02/20/tidsbruk_en/

Statistics Norway (2008): Survey of consumer expenditure 2005 - 2007 . From: http://www.ssb.no/english/subjects/05/02/fbu_en/

Statistics Norway (2009a): Increase in NO X emissions . From: http://www.ssb.no/english/subjects/01/04/10/agassn_en/

Statistics Norway (2009b): Industrial activities . Table 03109 in the StatBank. From: http://statbank.ssb.no//statistikkbanken/default_fr.asp?PLanguage=1

Statistics Norway (2009c): High building prices in Norway . From: http://www.ssb.no/english/subjects/08/02/pppvare_en/

Statistics Norway (2009d): Agriculture and forestry . Table 04414 in the StatBank. From: http://statbank.ssb.no//statistikkbanken/default_fr.asp?PLanguage=1

Statistics Sweden (2008): Hushållens ekonomi . From: www.scb.se

Statistics Sweden (2009): Näringsverksamhet . From: http://www.scb.se/Pages/SubjectArea____11154.aspx

UK Emissions Inventory Team, AEA (2008): UK emissions of air pollutants 1970 to 2006 . AEA Report, pp 1-194

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