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Chapter 4: Industrial processes

4.1 Sector overview

New Zealand's industrial processes sector totalled 4202.53 Gg CO2 equivalent in 2004 and represented 5.6 percent of total greenhouse gas emissions. Emissions from industrial processes are now 987.92 Gg CO2 equivalent (30.7 percent) above the 1990 baseline of 3214.61Gg CO2 equivalent (Figure 4.1.1). The sector is dominated by emissions from the metal production category (carbon dioxide (CO2) and perfluorocarbons (PFCs)) at 56.3 percent of sectoral emissions.

Figure 4.1.1 Industrial processes sector emissions 1990-2004

Year

Gg CO2 equivalent (thousands)

1990

3.21

1991

3.49

1992

3.58

1993

3.62

1994

3.25

1995

3.39

1996

3.58

1997

3.30

1998

3.60

1999

3.66

2000

3.59

2001

3.86

2002

4.07

2003

4.35

2004

4.20

Figure 4.1.2 Industrial processes sector emissions in 2004 (all figures Gg CO2 equivalent)

 

Category

Gg CO2 equivalent

Percent of total

Mineral Products

612.79

14.6

Chemical Industry

599.39

14.3

Metal Production

2,364.50

56.3

Consumption of Halocarbons and SF6

625.85

14.9

The emissions included in the industrial processes sector arise from the chemical transformation of materials from one substance to another. Although fuel is also often combusted in the manufacturing process, emissions arising from combustion are included in the energy sector. Carbon dioxide emissions related to energy production, eg, refining crude oil and the production of synthetic petrol from natural gas, are also considered within the energy sector.

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, 2005);

  • 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.

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) from information collected through industry survey. The results are reported in the publication New Zealand Energy Greenhouse Gas Emissions 1990-2004 (MED, 2005).

Data on non-CO2 emissions are gathered 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. The 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 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 percent (MED, 2005). 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 612.79 Gg CO2 equivalent in 2004. Overall, emissions in the "mineral products" category have grown by 158.80 Gg equivalent (35.0 percent) from the 1990 level of 453.99 Gg CO2 equivalent. 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 (79 percent) and lime (20 percent). 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

Cement production

Since 1997, estimates of CO2 emissions from cement production have been calculated by multiplying the amount of clinker produced by a plant-specific emission 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 included along with emissions from the decomposition of CaCO3. Two cement companies currently operating in New Zealand take account of CO2 emissions from non-recycled cement kiln dust.

For the years 1990 to 1997, emissions are calculated using a Tier 1 approach. Total cement production is multiplied by a country-specific emission factor (0.51 t CO2 / t cement). Clinker data, which is required for the Tier 2 approach, cannot be provided by the companies for the years 1990-1996. Clinker data was recorded by the companies from 1997-2004 so the Tier 2 approach has been able to be implemented for this time period. The use of both Tier 1 and Tier 2 approaches for this time series is unavoidable as this the only dataset on CO2 emissions from cement production available in New Zealand.

The cement production activity data in the CRF reporter shows an increase from 1996-2004 however the CO2 implied emission factor for cement production has decreased over the same period. After 1996 the demand for cement in New Zealand increased. The local cement companies had to import clinker to meet this demand. CO2 emissions from cement production using the Tier 2 approach are only calculated from locally produced clinker (IPCC, 2000). The decrease in the CO2 implied emission factor can be explained by the increase in cement production over the period 1997-2004 while the CO2 emissions have remaining relatively steady due to the increase in imported clinker and a change in national standards for cement production (reducing the relative levels of clinker required to produce a given amount of cement).

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 percent of the SO2 will be absorbed by the alkaline clinker product. New Zealand uses a SO2 emissions factor calculated using industry specific information. This emission factor has been updated with improved information from industry available during 2005. The emission factor was able to be calculated using information from a sulphur mass balance study on one company's dry kiln process. This was able to determine the split between sulphur originated in the fuel and sulphur in the raw clinker material as sodium and potassium salts. The average emission factor is calculated as 0.64 kg SO2/t clinker and is weighted to take into account the relative activity of the two cement companies.

Lime production

There are three companies in New Zealand which make up the lime industry. Carbon dioxide emissions from lime production are supplied to the Ministry of Economic Development by industry. Emissions are calculated by multiplying the amount of lime produced by an emission factor. Prior to 2002, a single New Zealand specific emission factor based on the typical levels of impurities in the lime produced in New Zealand was applied to all lime. This is the only available information available for this source for the years 1990-2001. From 2002, the emission factors used were plant-specific as the companies were able to supply this information for these more recent years. There has been little change to the implied emission factor - from 0.72 t CO2 / t lime in 2001 to 0.73 t CO2 / t lime from 2002 to 2004.

The SO2 emissions emitted during lime production vary depending on the processing technology and the input materials. An industrial processes survey undertaken in 2005 resulted in an updated value for the average SO2 emission factor. The average emission factor is 0.48 kg SO2/t lime and is weighted to take sulphur measurements at the various lime plants into account.

Limestone and dolomite use

All limestone use in New Zealand is used for making lime or cement. Therefore emissions arising from these processes are reported under the cement and lime production categories as specified in the IPCC 1996 guidelines (section 2.5.1).

Soda ash production and use

There is no soda ash production in New Zealand. A survey of the industrial processes sector in 2005 was able to make some estimates of carbon dioxide emissions resulting from the use of soda ash in glass production after consultation with the sole glass manufacturer in New Zealand. The manufacturer was able to provide information on the amount of imported soda ash it utilised in 2005. It also provided approximate proportions of recycled glass over the last 10 years to enable back calculations because the soda ash amount is in fixed proportion to the production of new (rather than recycled) glass. Linear extrapolation of activity data from 1990 to 1995 was carried out in the absence of actual data. The IPCC default emission factor of 415 kg CO2 per tonne of soda ash is applied to calculate the CO2 emissions.

Asphalt roofing

There is only one company manufacturing asphalt roofing in New Zealand. Emissions are calculated using activity data supplied by the company. The industrial processes survey undertake in 2005 revealed an updated estimation of activity data for this source. The data has been updated and back calculated for the entire time series. 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 40 percent of the bitumen used for road paving is used for asphalt and 60 percent 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. The average solvent content in bitumen has been reducing in recent years as methods of laying bitumen have improved (CRL Energy Ltd, 2006).

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. 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 percent, there is no possibility of this level of NMVOC emissions. For the 2002 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.

The industrial processes survey undertaken in 2005 showed that the fraction of weight of bitumen used to produce chip-seal has been changing over recent years as methods of laying bitumen have improved. From 1990 to 2001 the fraction by weight of bitumen used to produce chip-seal was 0.80. From 2002 to 2003 it was 0.65 and in 2004 the fraction was 0.60. The emissions of NMVOCs in the CRF have been updated for the time-series to reflect this changing fraction.

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. The industrial processes survey undertaken in 2005 was able to obtain estimates of CO2 from soda ash use (see soda ash paragraph above) and SO2 emissions from sodium sulphate decomposition. It has been assumed that the IPCC emissions factor is based on total glass production which includes recycled glass input. Activity data has been updated with estimates for years prior to 1995 extrapolated. NOx and CO emissions are assumed to be associated with fuel use while NMVOC and SO2 emissions are assumed to be associated with the industrial process because they are associated with the raw materials.

4.2.3 Uncertainties and time-series consistency

Uncertainties in CO2 emissions are assessed as ± 5 percent 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, 2006).

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%

±40%

Lime

±1%

±80%

Asphalt roofing

±30% (±50% for 1990-2000)

±40%

Road paving with asphalt

±10%

±15% (chip-seal fraction and solvent emission fraction) to ±25% (solvent dilution).

Glass

0%

NMVOC: ±50% SO2: : ±10%

4.2.4 Source-specific QA/QC and verification

CO2 emissions from cement production has, in past inventories, been identified as a key source category. In the 2004 inventory, CO2 from cement production was not identified as a key source category (level assessment) but was in 1990. 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 double checked with industry experts where possible to verify the data. The small number of companies in this category facilitates the complete coverage of the category.

4.2.5 Source-specific recalculations

The inclusion of estimates of CO2 arising from the use of soda ash in the glass production industry has been included for the first time in the 2004 inventory for all years from and including 1990. This has resulted in CO2 emissions attributed to the mineral products category being recalculated for the entire time series.

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, carbon black, ethylene, dichloroethylene, styrene, coke or caprolactam in New Zealand.

Emissions from the chemical industry category comprised 599.39 Gg CO2 equivalent emissions in 2004 and have increased 154.03 Gg CO2 equivalent (34.6 percent) from the 445.37 Gg CO2 equivalent estimated in 1990. CO2 emissions from ammonia/urea production account for 68.3 percent 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 of the carbon in the gas used to produce the urea is eventually released. Emissions are calculated by multiplying the quantities of the different types of gas used by their respective emission factors (Annex 2.3). In accordance with IPCC guidelines (IPCC, 1996) it is assumed that the carbon in urea is eventually released after it is applied to the land.

For the 2004 inventory emissions from urea production have been allocated to the "ammonia production" category. This was recommended in the review of New Zealand's 2003 inventory. In the 2003 inventory they were reported under a country-specific category "urea production".

Non-CO2 emissions are considered by industry experts to all be arising from fuel combustion and are covered in the energy sector.

Formaldehyde

Formaldehyde is produced at five plants in New Zealand. NMVOC emissions are calculated from company supplied activity data and a country-specific emission factor of 1.5 kg NMVOC/t of product. Emissions of CO and CH4 were undetectable for at least two plants representing 60 percent of total formaldehyde production.

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). Emissions are reported in the energy sector.

The major non-fuel related emissions from the process are NMVOCs. 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, 2006).

Fertiliser

Superphosphate is produced by two companies (each with three plants) in New Zealand. Most of these plants produce sulphuric acid as a first step while one plant now imports acid. Both companies have supplied activity data and emission factors for sulphur dioxide (SO2). Sulphur dioxide is the only indirect greenhouse gas emitted from the production of superphosphate fertiliser. The majority of these emissions are released during sulphuric acid production. 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 by New Zealand industry experts 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 for superphosphate and one set was identified as an outlier. The SO2 emission factor for the other company was assessed to be appropriate for both companies' superphosphate output.

Hydrogen

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 CH4 and steam. CO2 is a by-product of the reaction and is vented to the atmosphere. The implied emission factor is 6.45 kt CO2 per kt of hydrogen produced (MED, 2005).

4.3.3 Uncertainties and time-series consistency

Uncertainties in CO2 emissions are assessed as ± 5 percent 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, 2006). 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

± 0%

± 30%

Formaldehyde

± 2%

± 50% (NMVOCs)

Methanol

0%

± 50% (NOx and CO)

±30% (NMVOCs)

±80% (CH4)

Fertiliser

± 10% sulphuric acid

± 10% superphosphate

± 15% sulphuric acid

± 25 to ±60% superphosphate (varies per plant)

4.3.4 Source-specific QA/QC and verification

This category was checked in 2003 as part of quality control checks of non key categories so was not included in the schedule of non key categories to be checked in the 2004 inventory.

4.3.5 Source-specific recalculations

Ammonia was allocated from a country-specific category created during the 2003 inventory "urea production" to the "ammonia production" category as recommended by the international review team (UNFCCC, 2006).

Activity data has been estimated for all years for formaldehyde and EF for NMVOCs changed from IPCC default to a country-specific one (1.5 kg NMVOC/tonne formaldehyde).

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" category rose 2.5 percent from the 2,305.79 Gg CO2 equivalent recorded in 1990. CO2 emissions account for 96.6 percent of emissions in this category with another 3.4 percent from PFCs. In 2004, the level of CO2 emissions has increased by 496.48 Gg CO2 equivalent (27.8 percent) 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 2004, a decrease of 434.90 Gg CO2 equivalent (84.3 percent).

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

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 emission factor applied to the sub-bituminous coal used as a reducing agent is 93.7 kt CO2 / PJ. This emission 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 uses a modification of the Tier 2 approach 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. 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 emission factor based on the average implied emission factor for the plant for the years 2000-2004 (around 0.1 t CO2 / t steel). The Ministry of Economic Development advises 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 (CRL Energy Ltd, 2006).

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). Carbon anode oxidisation is responsible for almost 90 percent of the CO2 emissions from aluminium production. 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 (Bloor, 2005). Other emissions come from fuel combustion (various fuels are used-heavy fuel oil, LPG, petrol and diesel) and are included in the energy sector (MED, 2005; Bloor, 2005).

The IPCC default emission factor is used for NOx emissions. Plant specific emission factors are used for 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.

Emissions of the two PFCs (CF4 and C2F6) from the production of aluminium are supplied by the operator of New Zealand's sole aluminium smelter. The PFC emissions from aluminium smelting are calculated using a Tier 2 method. This involves using the IPCC default coefficients for Centre Worked Prebake 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, with no data 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 Centre Worked Pre Bake technology are used. The smelter advises that 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. Companies operating in New Zealand confirm they do not emit indirect gases (NOx, CO and SO2) with one using the Cyanisorb recovery process to ensure everything is kept under negative pressure to ensure no gas escapes to the atmosphere. Gold and silver production processes are listed in IPCC (1996) 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 2004.

4.4.3 Uncertainties and time-series consistency

Uncertainty in CO2 emissions is assessed as ± 5 percent 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, 2006). 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%

± 20-30% (CO)

± 70% (NOx)

Aluminium

0%

± 5% (SO2)

± 40% (CO)

± 50% (NOx)

± 30% (PFCs) [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, 2006).]

4.4.4 Source-specific QA/QC and verification

CO2 emissions from iron and steel production and aluminium production are key categories for New Zealand. These sources have undergone a Tier 1 QC check in preparation of the 2004 inventory.

4.4.5 Source-specific recalculations

There are no source specific recalculations performed for this category for this inventory submission.

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 2004, emissions from this category totalled 7.14 Gg NMVOC. This was an increase of 1.24 Gg NMVOCs since 1990.

4.5.2 Methodological issues

Pulp and paper

There are a variety of pulping processes in New Zealand. These include:

  • Chemical (Kraft)
  • Chemical thermomechanical
  • Thermomechanical
  • Mechanical.

Mechanical pulp production in 2004 was responsible for 54 percent of all pulp production with chemical production responsible for 46 percent. Estimates of emissions from the chemical pulping process are calculated from production figures obtained from the Ministry of Agriculture and Forestry. 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. In absence of better information the NMVOC emission factor applied to the chemical pulping processes is also applied to the thermomechanical pulp processes to estimate the emissions from that source (CRL Energy Ltd, 2006). Emissions of CO and NOx from these processes are more likely to be fuel combustion related.

Food and drink

NMVOC are produced during the fermentation of cereals and fruits in the manufacture of alcoholic beverages. They are also produced during all processes in the food chain which occur after the slaughtering of animals or harvesting of crops. 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.

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, 2006). 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

5%

±50% (chemical pulp)

±70% (thermal pulp)

Food - alcoholic beverages

±5% (beer)

±20% (wine)

±40% (spirits)

±80% (beer and wine)

±40% (spirits)

Food - food production

±5-20% (varies with food type)

±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 performed for this category in this inventory submission.

4.6 Production of halocarbons and SF6 (CRF 2E)

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

4.7 Consumption of halocarbons and SF6 (CRF 2F)

4.7.1 Description

Emissions from hydrofluorocarbons (HFCs) totalled 625.85 Gg CO2 equivalent in 2004. This is an increase of 462.84 Gg CO2 equivalent (283.9 percent) from the 1995 level of 163.01 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 level and trend analysis of the 2004 inventory (Tables 1.5.2 and 1.5.3). SF6 emissions have increased from 12.14 Gg CO2 equivalent in 1995 to 21.49 Gg CO2 equivalent in 2004, an increase of 77.0 percent.

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 mid 1990s 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 and air conditioning
  • fire protection
  • 'other'.

The emissions inventory for SF6 is broken down into two source categories: electrical equipment and 'other'. In New Zealand, one electricity company accounts for 80-90 percent of the charge of SF6 used in electrical equipment.

4.7.2 Methodological issues

HFCs/PFCs

Information on bulk imports of HFCs and PFCs each year is based on data supplied by the Ministry of Economic Development. This information is derived from an annual survey of all importers and distributors of these chemicals. In past surveys (up until 2001), the Ministry of Economic Development had compiled a detailed breakdown of bulk HFCs using information from import licences for a range of mixtures that included HFCs and PFCs. This analysis has not been carried out for four years. Consequently there is no longer an accurate independent check on the total imports reported by bulk chemical suppliers.

Activity data was collected directly from importers and distributors to identify the end users of imported bulk HFCs and PFCs. This information was used to determine the proportion of bulk chemical used in each sub-source category.

Several additional importers were identified for this survey compared to the previous survey carried out in 2004. 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 1b approach. Due to a lack of disaggregated HFC data for refrigeration, potential emissions from refrigeration could not be calculated for each specific HFC chemical and as a result the total potential emissions for consumption of halocarbons are underestimated.

Table 4.7.1 Halocarbon and SF6 calculation methods and emission factors

HFC source Calculation method Emission factor

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 source

Calculation method

Emission Factor

Electrical equipment

IPCC GPG 2001 Eqn 3.17

Tier 3 approach based on overall consumption and disposal with country-specific EF of 1% and this was supplemented by information from equipment manufacturers and servicing contractors using IPCC default EF of 2% (Tier 2b approach).

Other applications

IPCC GPG 2001 Eqn 3.22

No emission factor required as 100% is emitted within two years

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 2004 are provided by the sole New Zealand supplier. The weighted average quantity of propellant per dose was calculated from information supplied by industry. There were no HFCs used in aerosols prior to 1996 and HFC-134a was not used in metered dose inhalers (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, 2006a).

Foam

The survey revealed one New Zealand manufacturer importing HFCs for foam blowing and some of the products are exported overseas for use in refrigeration manufacture. There is insufficient data to estimate the proportion of HFC emissions exported (CRL Energy 2006a). The manufacturer started HFC usage in 2000. From 2000 to 2003 the HFC used was HFC 134a. From 2004, a mixture of HFC-245fa/365mfc has been imported for use.

Stationary refrigeration/air conditioning

To estimate the actual emissions of HFCs and PFCs, all refrigeration equipment has been split into two groups: factory charged equipment and all other equipment which is charged with refrigerant on site. Information is available on the quantities of factory charged imported refrigeration equipment and on the amount of bulk HFC refrigerant used in that equipment.

The amount of new refrigerant used to charge all other equipment (which is charged on site after assembly) is assumed to be the amount of HFC refrigerant sold each year minus that used to manufacture factory charged equipment minus that used to top up all non-factory charged equipment.

Factory charged equipment consists of all equipment charged in factories (both in New Zealand and overseas), including all household refrigerators and freezers and all factory charged self-contained refrigerated equipment used in the retail food and beverage industry. All household air conditioners and most medium-sized commercial air conditioners are also factory charged although some extra refrigerant may be added by the installer for piping.

In terms of household refrigeration it is estimated that on average there are about 2.2 refrigerators and freezers per household in New Zealand (Roke, 2006). Imported appliances account for around half of new sales each year with the remainder manufactured locally. New Zealand also exports a significant number of factory charged refrigerators and freezers.

Commercial refrigeration includes central rack systems used in supermarkets, chillers used for commercial building air conditioning and process cooling applications, rooftop air conditioners and transport refrigeration systems. In most cases these types of systems are assembled and charged on site, although some imported units may already be pre-charged. Self-contained commercial equipment includes frozen food display cases, reach-in refrigerators and freezers, beverage merchandisers and vending machines.

New Zealand uses a top down Tier 2 approach and country-specific data to obtain HFC emissions from stationary refrigeration and air conditioning (IPCC equation 3.40, IPCC, 2001).

Mobile air conditioning (MAC)

The automotive industry has used HFC-134a as the refrigerant for mobile air conditioning (MAC) in new vehicles since 1994. HFC-134a is imported into New Zealand for use in the MAC industry through bulk chemical importers/distributors and within the air conditioning systems of imported vehicles. Industry sources report that air conditioning systems are retrofitted (with 'aftermarket' units) to new trucks and buses and to secondhand cars.

New Zealand uses the Tier 2 top down approach (IPCC equation 3.44, IPCC, 2001). 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.

Fire protection

HFCs and PFCs are used as substitutes to halons in portable (streaming) and fixed (flooding) fire protection (fire suppression) equipment. Halons have traditionally been used in areas that contain high-value equipment and where risks to personal safety are high. These include computer rooms, data centres and on aircraft.

HFC-based foams have only been used in fire protection systems in New Zealand since 1994. Within the New Zealand fire protection industry, the two main supply companies were identified as using relatively small amounts of HFC-227ea. The systems installed have very low leak rates with most emissions occurring during routine servicing and during accidental discharges.

The method selected for estimating emissions from this sub-source category is the bottom-up approach. For each year, an emission rate of 1.5 percent is applied to the total amount of HFC installed to get annual HFC-227ea emissions.

SF6

Actual and potential emissions of SF6 result primarily from the use of SF6 in electrical switchgear. For the 2004 inventory, emissions are calculated using the Tier 3c approach for the majority of electrical switchgear emissions and supplemented by information from equipment manufacturers and servicing contractors. One firm representing 80-90 percent of the total SF6 held in equipment provided sufficient information for the Tier 3 approach. A Tier 2b 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, 2006a). Potential emissions of SF6 were calculated and included in the 2004 inventory.

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, 2006a)

HFC source Uncertainty estimates

Aerosols

±56% for aerosol imports, ±60% in locally manufactured aerosols and ±10% from emissions from MDIs.

Solvents

Not occurring.

Foam

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

Stationary refrigeration/air conditioning

±10% on total HFC/PFC imported and in locally charged equipment. ±30% in factory charged equipment.

±28% in total HFC/PFC proportion used for charging new commercial refrigeration units.

Mobile air conditioning

Combined uncertainty ±43%.

Fire protection

Combined uncertainty ±32%.

SF6 source

Uncertainty estimates

Electrical equipment

Combined uncertainty ±20%.

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 2004 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

The 2005 survey for industrial processes was redesigned for HFCs from stationary refrigeration and air conditioning to capture more importers of HFCs and PFCs and to better identify the refrigerant associated with imported and exported factory charged refrigeration and air-conditioning units. This has resulted in HFC and PFC emissions higher (up to 3.6 times higher) than in previous inventory submissions. The approach used is assessed by industry experts to represent an upper limit for HFC/PFC emissions from commercial refrigeration and air conditioning but is the most accurate and complete data available. This survey has resulted in HFC and PFC emissions for this category being recalculated for the entire time series.

SF6 data has been updated for the years 1991-1992 and 2000-2003.

4.8 Other (CRF 2G)

4.8.1 Description

Panel products

Activity data is obtained from industry and supplemented with statistics from the Ministry of Agriculture and Forestry website. The NMVOC emission factors for particleboard and medium density fibreboard are derived from two major manufacturers. 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.