Energy

Electricity generation

Emissions from electricity generation are included in the energy industries sub-sector in the STGGI. Emissions are produced by the combustion of fuels to generate electricity that is supplied to the electricity grid for domestic and commercial use.

This sub-sector covers emissions resulting from electricity that is generated in Tasmania, some of which is exported for consumption in the National Electricity Market (NEM) via Basslink. Emissions from electricity imported via Basslink from other states in the NEM are accounted for in the emissions inventory for the generating state.

Direct Combustion

Emissions from direct combustion are covered by a number of energy sub-sectors in the STGGI (namely, Manufacturing Industries and Construction; Other Sectors; and Other). These sub‑sectors include all emissions that arise from the combustion of fuel for stationary energy used directly on site, such as:

• burning coal, liquefied natural gas or forestry residue to generate heat, steam or pressure for major industrial operations; and
• burning wood or gas for household heating and cooking.

The industries that generate these emissions include manufacturing; construction; agriculture and fisheries; residential; and commercial activities.

Emissions from these industries associated with the combustion of fuels to generate electricity, or fuel combustion in transport, are accounted for in the electricity generation and transport sub‑sectors respectively.

Transport

Emissions from the transport sub-sector are produced by the combustion of fuels such as petrol, diesel and liquefied petroleum gas in passenger and commercial motor vehicles; railways; domestic aviation; and shipping.

Emissions from the electricity used to power electric vehicles are accounted for in the electricity generation sub-sector.

Industrial processes and product use (IPPU)

Emissions from the IPPU sector are generated from a range of production processes that include:

• the calcination of carbonate compounds (eg cement, lime or glass production);
• carbon when used as a chemical reductant (eg iron, steel or aluminium production); and
• the production and use of synthetic gases such as hydrofluorocarbons (eg refrigeration, air conditioning, solvents) and sulphur hexafluoride (electrical equipment).

Emissions associated with the energy used in industrial production processes are accounted for in the electricity generation and direct combustion sub-sectors. For example, the emissions from cement manufacture include combustion of fuels (coal) for heat used in the manufacturing process. However, these combustion-related emissions are reported as energy emissions (direct combustion sub-sector) and not with IPPU, which only includes the emissions from calcination.

Agriculture

Emissions from the agriculture sector include emissions from:

• livestock digestion (enteric fermentation); and
• the release of nitrous oxide from cropping and pasture land, and manure management.

Enteric fermentation of plant material that is digested by livestock (cattle, sheep and pigs) results in methane emissions. Urine and dung deposited by grazing animals, and nitrogen leaching and run-off, results in emissions from microbial and chemical transformations that produce and consume nitrous oxide in the soil. Manure management produces emissions through the anaerobic decomposition of the organic matter contained in manure.

Emissions associated with the use of electricity, fuel consumption from operating agricultural equipment, and fuel consumption in transport, are accounted for in the energy sector. Emissions from land use change (eg clearing of forest land for the purpose of creating cropping and pasture land) are accounted for under the LULUCF sector.

Land use, land use change and forestry (LULUCF)

The LULUCF sector includes emissions and sequestration (removals or carbon sinks) of greenhouse gases from direct human-induced land use, land-use change and forestry activities. This includes emissions and sequestration associated with clearance of forested land and conversion to other land uses (cropland, grassland, wetlands and settlements), from new forests planted on previously unforested land, and from other practices that change emissions and sequestration (forest management, cropland management and grazing land management). Emissions from fuelwood consumption, controlled burning and wildfires on forest land are also included, as are removals associated with post-fire recovery. Carbon that accumulates in harvested wood products is included as a sink.

Combustion of fossil fuels associated with forestry and land management (eg diesel to run logging machinery and farming equipment) are accounted for in the direct combustion sub-sector. Emissions associated with livestock (eg enteric fermentation) and cropping (eg release of nitrous oxide), are accounted for in the agriculture sector.

Waste

Emissions from the waste sector are produced by the decomposition of organic waste in landfills and from the release of greenhouse gases during the treatment of wastewater. The anaerobic decomposition of organic matter from solid waste in landfills and wastewater treatment plants produces methane. The nitrification and denitrification of urea and ammonia in wastewater treatment plants produces nitrous oxide emissions.

Emissions associated with the energy used in the management and transportation of waste are reported in the electricity generation, direct combustion and transport sub-sectors.