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Chapter 4: Industrial processes

4.1 Sector overview

New Zealand's industrial processes sector totalled 4014.19 Gg CO2 equivalent in 2003 and represented 5.3% of total greenhouse gas emissions. Emissions from industrial processes are now 25% above the 1990 baseline of 3211.70 Gg CO2 equivalent (Figure 4.1.1). The sector is dominated by emissions from the metal production category (CO2 and PFCs) at 58.3% of sectoral emissions (Figure 4.1.2).

Figure 4.1.1 Industrial processes sector emissions 1990-2003

Year Gg CO2 equivalent
1990 3,211.70
1991 3,487.37
1992 3,576.65
1993 3,617.58
1994 3,209.68
1995 3,325.21
1996 3,486.07
1997 3,268.11
1998 3,479.85
1999 3,560.62
2000 3,511.70
2001 3,673.27
2002 3,824.38
2003 4,014.19

Figure 4.1.2 Industrial processes sector emissions in 2003 (all figures Gg CO2 equivalent)

Category Gg CO2 equivalent Percent of total
Metal Production 2339.64 58.3
Consumption of Halocarbons and SF6 420.54 10.5
Mineral Products 638.83 15.9
Chemical Industry 615.18 15.3

The emissions included in the industrial processes sector arise from the chemical transformation of materials from one substance to another. New Zealand has a relatively small number of plants emitting non-energy related greenhouse gases from industrial processes. However, there are six industrial processes in New Zealand that emit significant quantities of CO2 (MED, 2004):

  • the reduction of ironsand in steel production
  • the oxidisation of anodes in aluminium production
  • the production of hydrogen
  • the calcination of limestone for use in cement production
  • the calcination of limestone for lime
  • the production of ammonia and urea.

Although fuel is also often combusted in the manufacturing process, emissions arising from combustion are included in the energy sector. Additionally, CO2 emissions related to energy production e.g. refining crude oil and the production of synthetic petrol from natural gas, are also considered within the energy sector.

The industrial processes categories use a few common data sources and emission factors. For this reason, general information about methodologies and uncertainties are included in this section as an overview.

4.1.1 Methodological issues

Emissions of CO2 from industrial processes are compiled by the Ministry of Economic Development (MED) and reported in the publication 'New Zealand Energy Greenhouse Gas Emissions 1990-2003' (MED, 2004). Production and emissions data are provided to the MED by industry.

Data on non-CO2 emissions are gathered primarily through a questionnaire distributed directly to industry via consultants contracted to the Ministry for the Environment. The questionnaire requests information on greenhouse gas emissions and production, as well as on any relationship the companies have established between the two. This information is supplemented by information from industry groups and other statistical sources. IPCC default emission factors are applied to industry production data where no country-specific information is available. Full details of emission estimates and aggregate emission factors are included in the detailed category information and worksheets for this sector (Annex 8.2).

4.1.2 Uncertainties

The number of companies in New Zealand producing CO2 from industrial processes is small and the emissions of CO2 supplied by the companies are considered to be accurate to ± 5% (MED, 2004). The uncertainty surrounding estimates of non-CO2 emissions is greater than for CO2 emissions and varies with the particular gas and category. Uncertainty of non-CO2 emissions is discussed under each category.

4.2 Mineral products (CRF 2A)

4.2.1 Description

Emissions from the mineral products category comprised 638.83 Gg CO2 in 2003. Overall, the level of emissions in the mineral products category has grown by 42.5% from the 1990 level of 448.28 Gg CO2. There are no emissions of CH4 or N2O from the mineral products category.

This category includes emissions produced from chemical transformations in the production of cement and lime, soda ash production and use, asphalt roofing, limestone and dolomite use, road paving with asphalt and glass production. The emissions profile is dominated by production of cement (83%) and lime (17%). CO2 emissions from cement production are identified as a key category for New Zealand in 2003 (Tables 1.5.2 and 1.5.3). For both lime and cement production, only the emissions related to the calcination process are included in this category with the emissions from the combustion of coal reported in the energy sector.

4.2.2 Methodological issues

Lime production

CO2 emissions from lime production are supplied to the MED by industry. Emissions are calculated by multiplying the amount of lime produced by an emissions factor. Prior to 2002, a single New Zealand specific emissions factor based on the typical levels of impurities in the lime produced in New Zealand was applied to all lime produced. In 2002 and 2003, the emission factors used were plant-specific but there has been little change to the implied emissions factor - from 0.72 t CO2 / t lime in 2001 to 0.73 t CO2 / t lime in 2002 and 2003.

Cement production

Since 1997, estimates of emissions from cement production have been calculated by multiplying the amount of clinker produced by a plant-specific emissions factor for clinker, in accordance with IPCC Tier 2 methodology (IPCC, 1996). The emission factors used are based on the CaO and MgO content of the clinker produced. Therefore, emissions from the decomposition of MgCO3 into MgO and CO2 are counted along with emissions from the decomposition of CaCO3. Only one of the two cement companies currently operating in New Zealand takes account of CO2 emissions from non-recycled cement kiln dust. Although failing to take account of CaO lost in cement kiln dust has a small impact on CO2 emissions, New Zealand will endeavour to obtain estimates of these losses for the company in question in time for the next inventory submission in 2006.

For the years 1990 to 1997, emissions are calculated using a Tier 1 methodology as clinker data (which is needed for the Tier 2 methodology) for these years is not available. Total cement production is multiplied by a country specific emissions factor (0.51 t CO2 / t cement). While the implied emissions factor for 2003 is lower than this (0.43 t CO2 / t cement), the implied emissions factor in 1997 (0.49 t CO2 / t cement) is quite close. Therefore, the use of a Tier 1 methodology prior to 1997 has probably not had a large impact on the accuracy of emissions estimated for these years. However, New Zealand will investigate whether clinker data for all years can be sourced so that CO2 emissions from cement production can be calculated using the Tier 2 methodology for the entire time series.

SO2 is emitted in small quantities from the cement making process. The amount of SO2 is determined by the sulphur content of the raw material (limestone). The IPCC guidelines (IPCC, 1996) report that 70-95% of the SO2 will be absorbed by the alkaline clinker product. New Zealand uses the SO2 emissions factor supplied by industry from the wet process kilns. For lime manufacture, the SO2 emissions vary with the technology used. SO2 emissions are calculated by multiplying individual plant activity data with individual SO2 plant emission factors and summing the result.

Asphalt roofing

There is only one company manufacturing asphalt roofing in New Zealand. Emissions are calculated using activity data supplied by the company. Emission factors for NMVOC and CO are from the IPCC Guidelines (IPCC, 1996).

Road paving with asphalt

Data on emission rates and bitumen production are provided by the three main road paving companies. Estimates of national consumption of bitumen for road paving are confirmed by the New Zealand Bitumen Contractors Association. In New Zealand, approximately 35% of the bitumen used for road paving is used for asphalt and 65% is for chip-seal resealing. Solvents are rarely added to asphalt, so asphalt paving is not considered a significant source of emissions. The main emissions from the road paving industry are from chip-seal resealing. New Zealand still uses a wet 'cut-back' bitumen method rather than bitumen emulsions common in other countries (CRL Energy Ltd, 2004).

The IPCC Guidelines (1996) make no reference to cut-back bitumen but do provide default emission factors for the low rates of SO2, NOx, CO and NMVOC emissions from the asphalt plant. However, the IPCC recommended default road surface emissions factor of 320 kg of NMVOC per tonne of asphalt paved is not considered applicable to New Zealand. Since the bitumen content of asphalt in New Zealand is only 6%, there is no possibility of this level of NMVOC emissions. For the 2003 inventory, the New Zealand Bitumen Contractors Association provided the methodology shown in Box 4.1 for calculating the total NMVOC emissions from the use of solvents in the roading industry.

Box 4.1 Calculation of NMVOC emissions from road paving asphalt

NMVOC emitted = A x B x C x D

where:

A = The amount of bitumen used for road paving

B = The fraction by weight of bitumen used to produce chip-seal (0.80)

C = Solvent added to the bitumen as a fraction of the chip-seal (0.04)

D = The fraction of solvent emitted (0.75)

Glass production

There is only one major glass manufacturer in New Zealand. The IPCC Guidelines (1996) report that NMVOC may be emitted from the manufacture of glass and provide a default emissions factor of 4.5 kg NMVOC per tonne of glass output. There is no information from which an estimate of SO2 emissions (from sodium sulphate decomposition) can be made.

It has been assumed that the IPCC emissions factor is based on total glass production which includes recycled glass input. NOx and CO emissions are assumed to be linked with fuel use while NMVOC and SO2 emissions are assumed to be linked with the industrial process because they are associated with the raw materials.

Soda ash production and use

Negligible quantities of soda ash or sodium carbonate are produced in New Zealand. The guidelines (FCCC/SBSTA/2004/8) state that the NE notation is applicable and this is the notation used in the CRF Reporter software. It is acknowledged there is a lack of data for this source and gaining an estimate of soda ash for inclusion in the next inventory has been added to the New Zealand improvement plan (part of the QA/QC system).

4.2.3 Uncertainties and time-series consistency

Uncertainties in CO2 emissions are assessed as ± 5% as discussed in section 4.1.2. Uncertainties in non-CO2 emissions are assessed by the contractor from the questionnaires and correspondence with industry sources (CRL Energy Ltd, 2004).

Table 4.2.1 Uncertainty in non- CO2 emissions from the mineral products industry

Product Uncertainty in activity data Uncertainty in emission factors

Cement

0%

+20%

Lime

+1 to +10% (varies by producer)

+30%

Asphalt roofing

+20%

+40%

Road paving with asphalt

+10%

+15 to +25% (varies with factors in calculation equation)

Glass

0%

+50%

4.2.4 Source-specific QA/QC and verification

CO2 emissions from cement production were identified as a key source category for New Zealand in the 2003 inventory. In preparation of this inventory, the data for these emissions underwent Tier 1 QC checks. In the process of compiling non-CO2 emissions, activity data are cross-referenced, where possible, between companies and industry associations to verify the data. The small number of companies in this category facilitates obtaining a complete coverage of the category.

4.2.5 Source-specific recalculations

As explained in section 4.2.2, two different methods have been used to create the times series for cement production. There is not a large jump between 1996 and 1997 (when the methodology changed) and recalculation method options in Table 7.5 in Chapter 7 of IPCC Good Practice Guidance (2000) do not appear to be appropriate in this case for recalculating emissions from 1996 back to 1990. The 1996 IPCC guidelines for cement production (section 2.3.1) state that "the differences between the lime content and production of clinker and cement, in most countries, are not significant enough to affect the emission estimates". Therefore the data across the entire time-series using two different methods remains in the CRF without recalculation.

Figure 4.2.1 CO2 emissions from cement production using Tier and Tier 2 methods

Year

Tier 1 method (Gg CO2 equivalent)

Tier 2 method (Gg CO2 equivalent)

1990 366.662  
1991 343.3407  
1992 405.4102  
1993 461.1548  
1994 486.7511  
1995 503.3407  
1996 502.7542  
1997   503.361
1998   478.724
1999   521.078
2000   519.788
2001   523.978
2002   541.723
2003 4,014.19 527.471

4.3 Chemical industry (CRF 2B)

4.3.1 Description

This category reports emissions from the production of ammonia, nitric and adipic acid, silicon and calcium carbide, and other chemicals. The major chemical processes occurring in New Zealand that fall in this category are the production of ammonia and urea, methanol, hydrogen, fertiliser (superphosphate) and formaldehyde. There is no production of nitric acid, adipic acid, carbide, coke or caprolactam in New Zealand.

Emissions from the chemical industry category comprised 615.18 Gg CO2 equivalent emissions in 2003 and have increased 37.3% from the 448.17 Gg CO2 equivalent estimated in 1990. CO2 emissions from ammonia/urea production account for 63.4% of emissions in this category.

4.3.2 Methodological issues

Ammonia/urea

Ammonia is manufactured in New Zealand by the catalytic steam reforming of natural gas at New Zealand's sole ammonia/urea plant. The total amount of gas supplied to the plant is provided to the MED by the firm operating the plant. CO2 emissions are calculated based on the assumption that all carbon in the gas used to produce the urea is eventually released. Accordingly, just as with energy sector emissions, emissions are calculated by multiplying the quantities of the different types of gas used by their respective emission factors (Annex 2.3) In previous inventories it was assumed that a proportion of the carbon in the gas was permanently sequested in the urea. In accordance with IPCC guidelines it is now assumed that the carbon in urea is eventually released after it is applied to the land.

CO2 emissions from urea production were previously reported in the energy sector in Section 3.2.2 - 'Fuel combustion: manufacturing industries and construction (CRF 1A2)' but are now included in this section. The emissions have been reallocated given that they arise due to the similar nature and processes as emissions from ammonia production, which are classified as industrial process emissions. This change was recommended in the UNFCCC review of New Zealand's 2002 inventory (UNFCCC, 2004).

Non-CO2 emissions are calculated from activity data and emission factors supplied by the company. The company supplied emission factors are based on measurements from historical vent valve data and are considerably lower than the IPCC defaults (Annex 8.2 worksheets).

Formaldehyde

Formaldehyde is produced at four plants in New Zealand. Emissions are calculated from company supplied activity data and emission factors for CO and CH4. Emissions are calculated by multiplying individual plant activity data with individual emission factors and summing the result. The levels of CO and CH4 are usually very small or undetectable.

Methanol

Methanol is produced at two plants in New Zealand. The process to calculate CO2 emissions is shown in Box 3.1 (energy sector: manufacturing industries and construction) and are considered in the energy sector. The major non-fuel related emissions from the process are from NMVOC. Emissions are calculated from company supplied activity data and emission factors. The NMVOC emissions factor was estimated in 2001 from American Petroleum Institute methods for calculating vapour emissions from storage tanks. NOx and CO emission factors were measured in 1999. It is assumed the IPCC default factor for CH4 (2g CH4/kg production) is appropriate for New Zealand (CRL Energy Ltd, 2004).

Fertiliser

Superphosphate is produced by two companies (each with three plants) in New Zealand. Both companies have supplied activity data and emission factors. No reference is made to superphosphate production in the IPCC Guidelines (1996). A default emissions factor of 17.5 kg SO2 (range of 1 to 25) per tonne of sulphuric acid is recommended but it is assessed to be a factor of two to ten times too high for the New Zealand industry. Emission estimates are therefore based on industry supplied emission factors and activity levels. Checks were made between the supplied emission factors and one set was identified as an outlier. The SO2 emissions factor for the other company was therefore applied to all activity data.

Hydrogen

Estimates of emissions of CO2 from hydrogen production are supplied directly to the MED from the two companies involved. Most hydrogen produced in New Zealand is made by the New Zealand Refining Company as a feedstock at the Marsden Point refinery. Another firm produces a small amount which is converted to hydrogen peroxide. The hydrogen is produced from methane and steam. CO2 is a by-product of the reaction and is vented to the atmosphere. The implied emissions factor is 6.51 tonne CO2/tonne H2 produced (MED, 2004).

4.3.3 Uncertainties and time-series consistency

Uncertainties in CO2 emissions are assessed as ± 5% as discussed in section 4.1.2. Uncertainties in non-CO2 emissions are assessed by the contractor from the questionnaires and correspondence with industry sources (CRL Energy Ltd, 2004). These are documented in Table 4.3.1.

Table 4.3.1 Uncertainty in non-CO2 emissions from the chemical industry

Product Uncertainty in activity data Uncertainty in emission factors

Ammonia /Urea

± 2%

± 30%

Formaldehyde

± 20 to ±40% (varies per plant)

± 20 to ±80% (varies per plant)

Methanol

0 %

± 30 to ±80% (varies per gas)

Fertiliser

± 10% sulphuric acid

± 20% superphosphate

± 15% sulphuric acid

± 15 to ±30% superphosphate (varies per plant)

4.3.4 Source-specific QA/QC and verification

Improvements in New Zealand's QA/QC system has lead to QC checks being extended to a selection of non key source categories. In preparation of the 2003 inventory, hydrogen production emissions underwent a Tier 1 QC check.

4.3.5 Source-specific recalculations

Emissions of CH4 from methanol production were included for the first time in the 2002 inventory due to an omission in previous submissions. Emissions were back-calculated to 1997. The time-series has been updated again by the MED. This enabled CH4 emissions for all years in the time-series to be calculated using the IPCC default emissions factor of 2 g CH4/kg production.

4.4 Metal production (CRF 2C)

4.4.1 Description

The metal production category reports emissions from the production of iron and steel, ferroalloys, aluminium and the SF6 used in aluminium and magnesium foundries. The major metal production activities occurring in New Zealand are the production of iron, steel and aluminium. These sources are both key source categories for New Zealand (Table 1.5.2). PFC emissions from aluminium production are a key category in the trend analysis (Table 1.5.3). New Zealand has no production of coke, sinter or ferroalloys.

Emissions from the metal production industry comprised 2,339.64 Gg CO2 equivalent in 2003 and have increased 1.5% from the 2,305.79 Gg CO2 equivalent recorded in 1990. CO2 emissions account for 96.6% of emissions in this category with another 3.4% from PFCs. In 2003, the level of CO2 emissions has increased by 26.4% over the 1990 baseline. However, the level of PFCs has decreased from the 515.60 Gg CO2 equivalent in 1990 to 80.70 Gg CO2 equivalent in 2003, a decrease of 84.3%.

The decrease in PFC emissions is because the sole aluminium smelter in New Zealand now has a very low anode effect duration by world standards. Anode effects are caused by depletion of alumina. Because of the modern technology in use, and the fact that the smelter feeds alumina in relatively large quantities by modern standards (50 kg per feed compared to 2 kg per feed), alumina is introduced into the pot quickly and extinguishes the anode effect.

4.4.2 Methodological issues

Iron and steel

New Zealand calculates emissions from iron and steel manufacture based on the quantities of the reducing agents used and the quantities of other non-fuel carbon-bearing ingredients used in the process such as electrodes. An allowance is made for the carbon sequested in the steel.

There are two steel producers in New Zealand. The smaller plant, which produces approximately 200 kt of steel a year, operates an electric arc furnace turning scrap metal into steel. As this plant does not perform the operation of turning iron-ore into iron, emissions from this plant are comparatively small - less than 25kt of CO2 emissions per year. The other much larger steel plant produces steel from titanomagnetite ironsand and therefore produces the bulk of the emissions. A direct reduction process is used to smelt iron, where the primary reducing agent is sub-bituminous coal rather than coke, as in the traditional blast furnace method of smelting. The emissions factor applied to the sub-bituminous coal used as a reducing agent is 93.7 kt CO2 / PJ. This emissions factor is calculated based on the specific characteristics of the coal the plant uses. The molten pig-iron is converted to steel in a KOBM oxygen steel making furnace. Prior to 1998, the plant also melted over 100,000 t per year of scrap in an electric arc furnace.

New Zealand does not strictly adhere to the Tier 2 methodology for calculating emissions from iron and steel production. Firstly, New Zealand does not account for emissions from pig iron and steel production separately as all of the pig iron is transformed into steel by the steel plants. Secondly, the carbon in the ironsand, thought to be negligible, is not accounted for. Thirdly, due to lack of data, the carbon in the scrap metal consumed by the largest steel plant when it operated an electric arc furnace is not accounted for, although this omission should also have a negligible effect on emissions estimates. Finally, also due to a lack of data, for the years prior to 2000, emissions from the plant operating the electric arc furnace are calculated by multiplying steel production by an emissions factor based on the average implied emissions factor for the plant for the years 2000-2004 (around 0.1 t CO2 / t steel). This should not have a large effect on total iron and steel emissions, given emissions from this plant are small.

Care has been taken not to double-count coal use for steel-making in the energy sector as well as the industrial processes sector. New Zealand energy statistics for coal are disaggregated into coal used in steel making and coal used in other industries and sectors.

The non-CO2 emission factors are based on measurements in conjunction with mass balance (for SO2) and technical reviews.

Aluminium

CO2 emissions and production data are supplied by New Zealand's sole aluminium smelter. The technology type used on site is Centre Work Pre Bake (CWPB). The carbon consumption is multiplied by 3.812 to convert C to CO2 (as compared with 3.666 if the standard atomic weights ratio of 44/12 is used). This number is specific to Comalco smelters to take into account some other process losses (NZAS, 2005). The data reflect anode oxidisation which is responsible for almost 90% of the CO2 emissions from aluminium production. The remainder come from fuel combustion (various fuels are used - heavy fuel oil, LPG, petrol and diesel) and are included in the energy sector (MED, 2004; NZAS, 2005).

Emissions of the two PFCs from the production of aluminium (CF4 and C2F6) are supplied by the operator of New Zealand's sole aluminium smelter. The IPCC default emission factors are used for other non-CO2 emissions apart from CO and SO2. An industry supplied value of 110 kg CO per tonne (IPCC range 135-400 kg CO per tonne) is based on measurements and comparison with Australian CO emission factors. SO2 emissions are calculated from the input sulphur levels and direct monitoring.

The PFC emissions from aluminium smelting are calculated using a Tier 2 method. This involves using the IPCC default coefficients for CWPB technology in the slope equation together with smelter-specific operating parameters. Anode effect frequency is multiplied by duration (the smelter captures every anode effect both in terms of count and of duration through its process control software. All monitoring data are logged and stored electronically (no data are estimated) to give the value known as 'anode effect minutes per cell day'. This value is then multiplied by the hot metal tonnes and the slope factor to provide an estimate of CF4 and C2F6 emissions. The IPCC default slope coefficients of 0.14 and 0.018 for CWPB technology are used. To convert to tonnes of CO2 equivalents, the estimates of CF4 and C2F6 are multiplied by the global warming potentials 6,500 and 9,200 respectively. There are no plans by the smelter company to directly measure PFC emissions in the future so a smelter specific long term relationship between measured emissions and operating parameters is not likely to be established in the near future.

Other metal production

The only other metals produced in New Zealand are gold and silver. Gold and silver production processes are listed in the 'Revised 1996 IPCC Guidelines for National Greenhouse Gas Inventories' as sources of non-CO2 emissions. However, no details or emission factors are provided and no published information on emission factors has been identified. Consequently, no estimation of emissions from this source has been included in New Zealand's inventory for 2003.

4.4.3 Uncertainties and time-series consistency

Uncertainty in CO2 emissions is assessed as ± 5% as discussed in section 4.1.2. Uncertainties in non-CO2 emissions are assessed by the contractor from the questionnaires and correspondence with industry sources (CRL Energy Ltd, 2004). These are documented in Table 4.4.1.

Table 4.4.1 Uncertainty in non-CO2 emissions from the metal industry

Product Uncertainty in activity data Uncertainty in emission factors

Iron and Steel

0%

± 20% (CO), ± 50% (NOx)

Aluminium

0%

± 5% (SO2), ± 40% (CO),

± 50% (NOx)

± 30% (PFCs)1

1 There is no independent means of assessing the calculations of PFC emissions from the smelter. Given the broad range of possible emission factors indicated in the IPCC (2000) Table 3.10, and in the absence of measurement data and precision measures, the total uncertainty is assessed to be ±30% (CRL Energy Ltd, 2004a).

4.4.4 Source-specific QA/QC and verification

CO2 emissions from iron and steel production and aluminium production are key source categories for New Zealand. These sources have undertaken a Tier 1 QC check in preparation of the 2003 inventory.

4.4.5 Source-specific recalculations

CO2 emissions from iron and steel production have been recalculated for all years to 1990 as a result of errors being identified with the assumed carbon content of scrap and steel in previous inventories (emissions were over-estimated). This has resulted in a two-fold reduction in emissions.

4.5 Other production (CRF 2D)

4.5.1 Description

The other production category includes emissions from the production of pulp and paper, and food and drink. In 2003, emissions from this category totalled 6.68 Gg NMVOC.

4.5.2 Methodological issues

Pulp and paper

Emissions are reported from chemically produced pulp of which the Kraft process constitutes 95% of production. The split between mechanical and chemical pulp production is 52/48%. Estimates of emissions from the chemical pulping process are calculated from production figures obtained from Statistics New Zealand and the MAF. Emission estimates from all chemical pulping processes have been calculated from the industry-supplied emission factors for the Kraft process because using the IPCC default factors appears likely to significantly over-estimate emissions in the New Zealand context. The NMVOC emissions factor has also been applied to the thermomechanical pulp processes to estimate the emissions from that source (CRL Energy Ltd, 2004).

Food and drink

NMVOC are produced during the fermentation process and during all processes in food processing. Estimates of emissions have been calculated using New Zealand production figures from Statistics New Zealand and relevant industry groups with default IPCC emission factors (IPCC, 1996). No New Zealand specific emission factors could be identified. It is assumed that losses in spirit production represent total NMVOC emissions from New Zealand's production of spirits.

4.5.3 Uncertainties and time-series consistency

Uncertainties in non-CO2 emissions are assessed by the contractor from the questionnaires and correspondence with industry sources (CRL Energy Ltd, 2004). These are documented in Table 4.5.1.

Table 4.5.1 Uncertainty in non- CO2 emissions from the other production category

Product Uncertainty in activity data Uncertainty in emission factors

Pulp and paper

0%

±50% (chemical pulp)

±70% (thermal pulp)

Food - alcoholic beverages

0% (beer and wine)

±20% (spirits)

±80% (beer and wine)

±60% (spirits)

Food - food production

±5-20% (varies with food)

±80% (IPCC factors)

4.5.4 Source-specific QA/QC and verification

No specific QA/QC activities are performed for this category. However, where possible, activity data are cross-referenced between companies and industry associations to verify the data.

4.5.5 Source-specific recalculations

There are no source-specific recalculations due to methodology changes performed for this category.

4.6 Production of halocarbons and sulphur hexafluoride (CRF 2E)

New Zealand does not manufacture halocarbons and sulphur hexafluoride (SF6). Emissions from consumption are reported under section 4.7

4.7 Consumption of halocarbons and sulphur hexafluoride (CRF 2F)

4.7.1 Description

Emissions from HFCs totalled 403.96 Gg CO2 equivalent in 2003. This is an increase of 382% from the 1995 level of 83.77 Gg CO2 equivalent. This large increase is due to the replacement of CFCs and HCFCs with HFCs. HFC emissions are identified as a key category in the trend analysis of the 2003 inventory (Table 1.5.3). SF6 emissions have increased from 9.46 Gg CO2 equivalent in 1990 to 12.38 Gg CO2 equivalent in 2003, an increase of 30.9%.

HFCs and PFCs are used in a wide range of equipment and products from refrigeration systems to aerosols. No HFCs or PFCs are manufactured within New Zealand, however PFCs are produced from the aluminium smelting process (discussed in the metal production category). The use of HFCs/PFCs has increased since the early 1990's when CFCs and HCFCs began to be phased out under the Montreal Protocol. In New Zealand, the Ozone Layer Protection Act (1996) sets out a programme for phasing out the use of ozone-depleting substances by 2015. According to the 1996 IPCC guidelines, emissions of HFCs and PFCs are separated into seven source categories: aerosols, solvents, foam, mobile air conditioning (MAC), stationary refrigeration/air conditioning, fire protection and other.

The emissions inventory for SF6 is broken down into two source categories: electrical equipment and other. One electricity company accounts for 80-90% of the charge of SF6.

4.7.2 Methodological issues

Sulphur hexafluoride

Actual and potential emissions of SF6 result primarily from the use of SF6 in electrical switchgear. For the 2003 inventory, emissions are calculated using the Tier 3 methodology for the majority of electrical switchgear emissions and supplemented by information from equipment manufacturers and servicing contractors. One firm representing 80-90% of the total SF6 held in equipment provided sufficient information for the Tier 3 approach. A Tier 2 approach was taken for the rest of the industry. SF6 questionnaires were sent to the two importers of SF6 and New Zealand's main users of SF6, the electricity transmission, generation and distribution companies (CRL Energy Ltd, 2004a). Potential emissions of SF6 were calculated and included in the 2003 inventory.

HFCs/PFCs

The total quantity of HFC and PFC imported each year is based on data supplied by the MED. This is derived from an annual survey of all importers and distributors of these chemicals. Further information was collected directly from importers and distributors to identify the end users of the imported bulk chemicals and to determine the proportion of bulk chemical used in each sub-source category. Estimates of non-bulk imports of HFCs, PFCs and SF6 are obtained directly from industry associations, Statistics New Zealand and New Zealand manufacturers of aerosol products. The MED has in previous years compiled a detailed breakdown of bulk HFCs, however this was not available for the 2003 inventory. In the absence of this data, the breakdown has been extrapolated from the 2001 data (CRL Energy Ltd, 2004a).

Specific information required to complete the inventory was obtained via a questionnaire sent to New Zealand's importers of HFCs/PFCs, the main producers/exporters of household domestic/commercial refrigeration equipment, foam blowing companies, mobile air conditioning installers/servicers, fire protection companies and the only producer of HFC based aerosols. The New Zealand methodology follows the IPCC Tier 2 approach which accounts for the time lag between consumption and emissions of the chemicals. A summary of calculation methods and emission factors for HFCs is included in Table 4.7.1.

Potential emissions for HFCs and PFCs have been calculated using the Tier 1a method (bulk imports minus bulk exports). Due to a lack of disaggregated data for the years 1999-2001 for refrigeration, potential emissions from refrigeration could not be calculated and as a result the total potential emissions for consumption of halocarbons for those years are underestimated.

Table 4.7.1 Halocarbon and SF6 calculation methods and emission factors

HFC source Calculation method Emission factors

Aerosols

IPCC GPG 2001 Eqn 3.35

IPCC default factor of 50% of the initial charge per year.

Foam

IPCC GPC 2001 Table 3.17

IPCC default factor of 10% initial charge in first year and 4.5% annual loss of initial charge over an assumed 20 year lifetime.

Mobile air conditioning

IPCC GPG 2001 Eqn 3.44

Top-down approach does not require emission factors.

Stationary refrigeration/air conditioning

IPCC GPG 2001 Eqn 3.40

Top-down approach does not require emission factors.

Fire protection

IPCC GPG 2001 Eqn 3.51

Bottom up approach using emission rate of 0.015.

SF6 sources

   

Electrical equipment

IPCC GPG 2001 Eqn 3.17

Tier 3 approach based on overall consumption and disposal with country specific EF of 1%.

Other applications

IPCC GPG 2001 Eqn 3.22

No emission factor required as 100% is emitted within 2 yrs.

Aerosols

Activity data on aerosol usage are provided by the only New Zealand aerosol manufacturer using HFCs and the Aerosol Association of Australia/New Zealand. The New Zealand manufacturer also provided activity data on annual HFC use, domestic and export sales, and product loading emission rates. Data on the total number of doses contained in Metered Dose Inhalers (MDIs) used from 1999 to 2003 are provided by the sole New Zealand supplier. The weighted average quantity of propellant per dose was calculated from information supplied by industry. HFC-134a was not used in MDIs before 1995.

Solvents

A survey of distributors of solvent products and solvent recycling firms did not identify any use of HFCs or PFCs as solvents (CRL Energy Ltd, 2004a).

Foam

The survey revealed only one New Zealand manufacturer importing HFCs for foam blowing and some of the product is exported overseas. The manufacturer started HFC usage in 2000. There is insufficient data to estimate the proportion of HFC emissions exported (CRL Energy 2004a).

Stationary refrigeration/air conditioning

Emissions are estimated from factory charged equipment and all other equipment which is charged on site. Activity data to complete IPCC equation 3.40 (IPCC, 2000) are obtained from the survey.

Fire protection

There are two main supply companies using HFCs in New Zealand. The annual emissions factor for all years is estimated to be 1.5% of the total amount of HFC installed.

Mobile air conditioning (MAC)

First-fill emissions are calculated from vehicle fleet numbers provided by the New Zealand Transport Registry Centre and assumptions made on the percentage MAC installations. Operation and disposal data are obtained from industry survey and the New Zealand Transport Registry Centre.

4.7.3 Uncertainties and time-series consistency

The uncertainties surrounding estimates of actual emissions from the use of HFCs and PFCs varies with each application and is described in Table 4.7.2. For many sources there is no measure of uncertainty but a quantitative assessment is provided from expert opinion.

Table 4.7.2 Uncertainties in HFC/PFC calculations (from CRL Energy Ltd, 2004a)

HFC source Uncertainty estimates

Aerosols

±53% for aerosol imports, ±30% in locally manufactured aerosols and ±10% from emissions from MDIs.

Solvents

Not occurring.

Foam

±50% in activity level and ±50% in emission factors.

Mobile Air Conditioning

Vehicle numbers are assessed to have low uncertainty.

Proportion of vehicles with MAC is highly uncertain and ±25% on the amount of HFC supplied to the MAC industry.

Stationary Refrigeration/Air Conditioning

±15% on total HFC/PFC imported and in locally charged equipment. ±60% in factory charged equipment.

±20% in total HFC/PFC proportion used for charging new commercial refrigeration units (largest source of uncertainty).

Fire Protection

±10% on the total amount of HFC installed and ±30% in the annual emissions factor.

SF6 source

 

Electrical equipment

±20% (Transpower) and ±60% (other companies) in emission factors.

±10% for total SF6 installed.

±30% for SF6 in new and retired equipment.

Other applications

±30% for tracer usage activity data.

±50% for medical use activity data.

4.7.4 Source-specific QA/QC and verification

In preparation of the 2003 inventory, the data for consumption of halocarbons and SF6 underwent a Tier 1 QC check. During the collection and calculation of data, activity data provided by industry are verified against national totals where possible and unreturned questionnaires and anomalous data are followed up and verified to ensure an accurate record of activity data.

4.7.5 Source-specific recalculations

There are no source-specific recalculations due to methodology changes performed for this category.

4.8 Other (CRF 2G)

4.8.1 Description

Panel products

Activity data and emission factors for NMVOC emissions are obtained from two plants that manufacture panel products. The activity data are supplemented from statistics from the MAF website. An assumption was made that the industry-supplied NMVOC emission factors are applicable to all particleboard and fibreboard production in New Zealand. There is no information in the IPCC guidelines (1996) for this category.