Emissions by sector

This section provides a sectoral analysis, from a Tasmanian perspective, of the greenhouse gas emissions for the five reporting sectors.

Energy

The energy sector includes the following sub-sectors:

• Energy industries: includes emissions that result from the generation of electricity as well as combustion emissions from petroleum refining, oil and gas extraction and processing, coal mining and solid fuel manufacturing.
• Manufacturing industries and construction: includes emissions from on-site combustion of fossil fuels by the manufacturing, non-energy mining and construction sectors.
• Transport: includes emissions from the direct combustion of fuels in transportation by road, rail, domestic aviation and domestic shipping.
• Other sectors: includes emissions from the direct combustion of fuels used by the commercial, institutional and residential sectors, as well as fuel used by agricultural, fishery and forestry equipment.
• Other: includes all remaining fuel combustion emissions such as those from engine lubricants and greases.
• Fugitive emissions from fuels: includes emissions associated with the extraction and distribution of fossil fuels such as coal, oil and natural gas.
• CO₂ transport and storage: includes emissions related to carbon capture and storage (CCS). Tasmania does not currently have any CCS projects operating.

The contribution of these sub-sectors to Tasmania’s energy sector greenhouse gas emissions is shown in Table 3 and Figure 3.

The emissions associated with electricity generated in Victoria and imported into Tasmania via Basslink are not included in Tasmania’s inventory; but rather are included in the emissions estimates for Victoria.

In 2015-16, the transport sub-sector continued to be the largest contributor to emissions from the energy sector, increasing by 8 per cent since 1989-90. However, emissions have declined by almost 18 per cent from a peak in 2008, despite an additional 80,039 vehicle registrations over this period, indicating an increase in the fuel efficiency of vehicles. (Note: From 505,151 vehicles registered in 2008 to 585,190 in June 2016; Department of State Growth, Historical Registration & Licensing Statistics.)

* Note the emissions from the ‘other sectors’ and ‘fugitive emissions from fuels’ sub-sectors are not available for reporting by sub-sector. However, emissions from those sub-sectors are included in the totals set out in Table 3, which are accordingly different from the sum of figures available for publication.

Table 3: Change in Tasmania’s energy sector greenhouse gas emissions between the 1989-90 baselines year and 2015-16, by sub-sector

Table 3 shows that the energy sector produced 3.98 Mt CO₂-e of emissions in 2015-16 and was the State’s highest emitting sector, with the various sub-sectors showing significant fluctuations in recent times. Emissions from the manufacturing industries and construction sub-sector increased by 25 per cent since the baseline year of 1989-90 to 1.25 Mt CO₂-e.

Despite the increase in emissions for the transport and manufacturing industries and construction sub-sectors, Tasmania’s emissions from the energy sector overall are relatively low compared with other Australian jurisdictions, given the State’s high levels of renewable hydro-electric and wind generation.

There was a notable increase in emissions for the energy industries sub-sector in 2015‑16 compared to the previous year, despite a decrease in this sub-sector in recent years due largely to reduced operation of the Tamar Valley Power Station (shown in Figure 3). During the electricity supply challenges in 2015-16, including the Basslink outage, Hydro Tasmania imported a number of portable diesel generators and recommissioned the Tamar Valley Power Station to meet Tasmania’s electricity demand. The diesel generators produced approximately 55 gigawatt hours of electricity into the Tasmanian grid and were decommissioned by 30 June 2016. (Source: Office of the Tasmanian Economic Regulator, Energy in Tasmania – Performance Report 2015-16 (December 2016), page 4.)

Figure 3: Tasmania’s energy sector greenhouse gas emissions from the 1989-90 baseline year to 2015-16, by sub-sector

Industrial processes and product use

The industrial processes and product use sector includes the following subsectors:

• Mineral industry: includes emissions that result from mineral processing industries, such as cement, lime, glass and limestone production and road paving with asphalt.
• Chemical industry: includes emissions from chemical production industries, such as soda ash and ammonia.
• Metal industry: includes emissions from the metal processing industries, such as aluminium, steel, iron and zinc production.
• Non-energy products from fuels and solvents use: includes emissions from production of lubricants, greases and solvents.
• Electronics industry: includes emissions from manufacture of integrated circuitry, semiconductors and photovoltaics.
• Product uses as substitutes for ozone depleting substances (ODS): includes emissions from synthetic halocarbons used in refrigeration, air-conditioning, foam blowing, fire protection and aerosols.
• Other product manufacture and use: includes emissions associated with the manufacture of other electrical equipment and compounds such as nitrous oxide, sulphur hexafluoride and perfluorocarbons.
• Other: includes emissions related to food and beverage industries, including the processing of meat, milk products and salmon, and the manufacture of beer, wine and alcoholic spirits. (AgriGrowth Tasmania notes developments in the food and beverage industries through its annual Agri-Food ScoreCard.)

The contribution of these sub-sectors to Tasmania’s industrial processes and product use sector greenhouse gas emissions is shown in Table 4 and Figure 4.

Despite an increase from the baseline year by almost 16 per cent in 2014-15, greenhouse gas emissions from the industrial processes and product use sector have shown a correction in 2015-16 and have only increased by around 4 per cent since 1989-90 as shown in Table 4.

* Note the emissions from the chemical industry, metal industry and electronics industry sub-sectors are not available for reporting by individual sub-sector. However, emissions from those sub-sectors are included in the totals set out in Table 4. Note also that some total emissions and percentage change calculations may not agree due to rounding.

Table 4: Change in Tasmania’s industrial processes and product use sector greenhouse gas emissions between the 1989-90 baseline and 2015-16, by sub-sector

Figure 4 shows that emissions from the mineral industry sub-sector have remained relatively steady since 1989-90, despite a peak of 0.71 Mt CO₂-e in 2014‑15, while the emissions from product uses as substitutes for ozone depleting substances have increased steadily since the mid-1990s and the introduction of the Montreal Protocol.

Figure 4: Tasmania’s industrial processes and product use sector greenhouse gas emissions from the 1989-90 baseline year to 2015-16, by sub-sector

Agriculture

The agriculture sector includes the following subsectors:

• Enteric fermentation: includes emissions from the digestive processes of ruminant animals such as cows, sheep, pigs and goats.
• Manure management: includes emissions from the decomposition of organic matter in manure under anaerobic conditions.
• Rice cultivation: includes emissions during rice growing from the decomposition of plant residues and other organic carbon material in the soil.
• Agricultural soils: includes emissions from microbial and chemical transformations that produce and consume nitrous oxide in the soil.
• Liming: includes carbon dioxide emissions from the addition of limestone and dolomite to the soil to improve soil quality and plant growth.
• Urea application: includes the loss of carbon dioxide from the addition of urea-based fertilisers to the soil.
• Other carbon containing fertilisers: includes the loss of carbon dioxide from the addition of other carbon-based fertilisers to the soil.
• Other: includes emissions from other sources of agricultural practices.

The agriculture sector includes emissions of methane and nitrous oxide only (that is, non-carbon dioxide gases) from livestock, crops, and agricultural and forest soils, and the emissions of carbon dioxide from the application of carbon-containing soil additives.

Tasmania’s emissions from the various agriculture sub-sectors for the baseline year 1989-90 and 2015-16 are shown in Table 5.

Note that some total emissions and percentage change calculations may not agree due to rounding.

Table 5: Change in Tasmania’s agriculture sector greenhouse gas emissions between the 1989-90 baseline year and 2015-16, by sub-sector

Emissions from Tasmania’s agricultural sector have declined by around 10 per cent since 1989-90. In 2016, the majority of emissions from the agriculture sector can be attributed to enteric fermentation, which takes place in the digestive system of cattle, sheep, pigs and goats. The impact that the enteric fermentation sub-sector has on total emissions from the agriculture sector is demonstrated in Figure 5.

Figure 5: Tasmania’s agriculture sector greenhouse gas emissions from the 1989-90 baseline year to 2014-16, by sub-sector

Reported emissions from Tasmania’s agricultural sector is subject to fluctuation and is affected by a combination of factors including: the number of dairy and beef cattle, sheep and pigs; and the number of lot-fed and pasture-fed animals. Figure 6 shows that the recent decline in sheep and cattle numbers have been the most likely driver of decreasing emissions from the sector.

Seasonal variability also affects emissions in the agricultural sector by impacting farming practices and the quantity and quality of feed for livestock. 2015-16 was a challenging year for our farmers, as Tasmania experienced a number of extreme weather events including: a prolonged dry period with record low rainfall early in the year; the worst statewide flooding in 40 years occurred late in the year; and snowfall to low elevations in some areas.

The agricultural soils sub-sector produces the second highest emissions in Tasmania and includes emissions of nitrous oxide (N₂O) from soils, which are added to the soil through processes including the application of nitrogen fertilisers, crop residues or animal wastes and sewage sludge to pastures, and mineralisation due to cultivation of organic soils or loss of soil carbon.

Figure 6: Comparison of agriculture (enteric fermentation) emissions and livestock numbers (‘000s)

(Note: Livestock numbers have been sourced from the Australian Bureau of Statistics, 7121.0 - Agricultural Commodities, Australia series.)

Land use, land use change and forestry

The Land Use, Land Use Change and Forestry (LULUCF) sector includes the following sub-sectors:

• Forest land: includes emissions and sinks from plantations, harvested native forests and other native forests. Emissions from fuelwood consumption, controlled burning and wildfire in forests are also included, as are sinks associated with post-fire recovery.
• Cropland: includes emissions and sinks from the cultivation of crops such as orchards and vineyards, and practices such as crop rotations, stubble management, tillage techniques and application of fertilisers, manures and irrigation.
• Grassland: includes emissions and sinks from changes in land management practices, including changes in shrub or sparse woody vegetation and disturbances such as a fire.
• Wetlands: includes emissions and sinks from human-induced changes in areas of sparse woody vegetation, loss of seagrass beds due to capital dredging and N₂O emissions from aquaculture operations.
• Settlements: includes emissions and sinksfrom the conversion of forest land to residential, commercial and transport infrastructure. It also includes emissions from the conversion of wetlands (tidal marsh) to settlements.
• Harvested wood products: includes emissions from the harvesting and manufacture of wood products and by the use and disposal of wood.

Tasmania’s emissions from the LULUCF sector between 1989-90 and 2015-16 are shown in Table 6 and Figure 7.

Note that some total emissions and percentage change calculations may not agree due to rounding.

Table 6: Change in Tasmania’s LULUCF sector greenhouse gas emissions between the 1989-90 baseline year and 2015-16, by sub-sector

Tasmania’s forest land sub-sector changed from a major source of greenhouse gas emissions at 6.2 Mt CO₂-e in the baseline year to become a carbon sink of -9.96 Mt CO₂-e in 2015-16.

The LULUCF sector has been affected by the structural change experienced by the forestry industry over the past decade. This change has resulted in annual volumes of softwood and hardwood timber harvested from both native forests and plantations declining from a peak of 7.0 million cubic metres (m³) in 2007-08 to 2.4 million m³ in 2012-13.[10] However, this has since increased to 4.3 million m³ in 2015-16.

The emissions from harvested native forests and plantations are captured under the forest land sub-sector, shown in Figure 7 as declining from a peak in 2002-03. This decline in emissions is largely due to the regrowth and increased carbon sequestration of previously harvested forests, and offsets an increase in the volume of harvested hardwood from plantations in 2015-16, which was up 57 per cent from the previous year to around 2.0 million m³. (Source: ABARES, Australian forest and wood products statistics September and December quarters 2016, overview report.)

The State and Territory Greenhouse Gas Inventories 2016 also reports greenhouse gas emissions from human-induced disturbances such as forest harvesting, and natural events (bushfire or drought). This is captured in the forest converted to other land uses sub-sector.

In January 2016, North and North-West Tasmania experienced multiple fires caused by dry lightning strikes, which affected approximately 20,125 hectares of the Tasmanian Wilderness World Heritage Area. (Source: Australasian Fire and Emergency Service Authorities Council Limited, A review of the management of the Tasmanian fires of January 2016 , April 2016.) The impact of naturally occurring bushfires is monitored for a period of time to determine if any land use changes occur after the bushfire. Emissions from bushfires are smoothed over this monitoring period until a permanent land use is identified.

A number of factors makes it difficult to forecast the potential impact on the emissions profile of Tasmania’s LULUCF sector. These include: the complexity of the methodologies and models used to estimate levels of carbon sequestration and emissions for Tasmania’s public and private native forests and plantations; changing local and global markets for Tasmanian grown timber products; and impacts associated with a changing climate such as increased bushfire risk, pathogens and reduced growth from heat stress.

Figure 7: Tasmania’s LULUCF sector greenhouse gas emissions from the 1989-90 baseline year to 2015-16, by sub-sector

Waste

The waste sector includes the following subsectors:

• Solid waste disposal: includes the emissions from the anaerobic decomposition of organic matter in landfill.
• Biological treatment of solid waste: includes the emissions from processes such as windrow composting and enclosed anaerobic digestion.
• Incineration and open burning of waste: includes the emissions from the incineration of solvents and municipal and clinical waste.
• Wastewater treatment and discharge: includes the emissions from the anaerobic decomposition of organic matter in wastewater and the chemical processes of nitrification and denitrification in wastewater treatment plants.

The waste sector is a minor contributor to Tasmania’s total greenhouse gas emissions. In 2015-16, emissions from this sector totalled 0.35 Mt CO₂-e, which is a reduction of over 27 per cent since 1989-90 as shown in Table 7.

Note that some total emissions and percentage change calculations may not agree due to rounding.

Table 7: Change in Tasmania’s waste sector greenhouse gas emissions between the 1989-90 baseline year and 2015-16, by sub-sector

In Tasmania, there was an increase in waste ending up in landfill from 415,443 t in 2014-15 to 427,358 t in 2015-16, of which 233,520 t was recovered through recycling and composting. (Source: Environment Protection Authority, Annual Report 2015-16, page 27.)

Nationally, there has been a decrease in emissions from solid waste disposal, mainly due to methane recovery. Furthermore, as rates of recycling have increased, paper disposal has declined as a share of total waste disposed. In Tasmania a number of landfill sites have installed methane capture and recovery equipment for electricity production or gas flaring, which has contributed to the almost 20 per cent reduction in emissions from the solid waste disposal sub-sector.

In recent years, state and territory waste management policies have driven the viability of alternative waste treatment options. Changes in estimates for wastewater treatment and discharge emissions are largely driven by changes in industry production, population loads on centralised treatment systems and the amount of methane recovered for combustion or flaring.

Figure 8: Tasmania’s waste sector greenhouse gas emissions from the 1989-90 baseline year to 2015-16, by sub-sector.