Example tooltip content.
Landfill gas emissions can be estimated a few ways using different information inputs. Simple methods to estimate landfill gas tend to yield lower accuracy results. More complex methods requiring several steps and datapoints tend to yield higher accuracy results.
Regardless of the estimation method, the results are still estimations only. Where estimations tend to indicate landfill gas emissions are conducive to active landfill gas capture and combustion, ground-truthing with consultants and landfill gas contractors is usually required before committing to a permanent project.
One example simple method and one example complex method are highlighted below. These are not the only desktop estimation methods available for landfill gas, but they are the two methods administered by government agencies in Australia. These and most other estimation methods tend to express landfill gas emissions in terms of its carbon dioxide equivalent, or CO2-e.
The National Greenhouse Accounts (NGA) provides emissions factors and methods to assist organisations and individuals in estimating greenhouse gas emissions from various sources. Councils and other entities that are not mandated to do greenhouse gas reporting tend to use NGA factors to roughly estimate emissions.
NGA factors are updated annually. For solid waste emissions from landfilling, emissions factors are multiplied by different waste stream tonnages: municipal solid waste (MSW), commercial and industrial (C&I), and construction and demolition (C&D). Alternatively, if the composition of waste is known (food; paper and cardboard; garden and green…), emissions factors can be multiplied by these tonnages instead.
The emissions outputs from this method represent ‘lifetime emissions’ from a unit of waste. That is to say, emissions from waste landfilled in 2026 is expressed in one lump sum for the same year. In reality, waste that contains organic matter decays slowly in landfill environments and the actual emissions associated with that decay is released over 30+ years from the time a unit of waste is deposited.
TIP: If your council is using the NSW Government sponsored Cassora platform to track emissions, calculations using NGA factors can be performed automatically in Cassora.
Worked example:
Council A wants to do a rough estimation of landfill emissions from all the waste landfilled in one year. In 2025, the NGA factors for waste stream tonnages were:
MSW = 1.6
C&I = 1.3
C&D = 0.2
Council A knows its tonnages for these categories due to weighbridge data and annual reporting requirements to the EPA:
MSW = 10,000t
C&I = 12,000t
C&D = 8,000t
Therefore:
Total lifetime landfill emissions from waste landfilled in 2025 = (1.6 x 10000) + (1.3 x 12000) + (0.2 x 8000) = 33,200t CO2-e.
The National Greenhouse and Energy Reporting (NGER) Scheme is a single national framework for reporting organisation/company information about greenhouse gas emissions, if certain emissions thresholds are met. Very few councils in NSW are required to report under the NGER Scheme.
Various tools have been developed to enable NGER Scheme reporting. One such tool is the Solid Waste Calculator (SWC). Any entity that landfills waste can download and use the SWC to estimate their landfill emissions, even if they are not required to report emissions under the NGER Scheme. The NGER SWC is the preferred desktop estimation method of the NSW Government for local councils. The SWC is hosted and updated by the Australian Government and allows for more refined data inputs and emissions outputs. Principally, the SWC emissions estimation outputs from waste landfilled today are ‘smoothed’ over future years. Waste that contains organic matter decays slowly in landfill environments and the actual emissions associated with that decay is released over 30+ years from the time a unit of waste is deposited.
The Hunter Joint Organisation, in collaboration with 100% Renewables and NSW EPA, has developed a resource for estimating landfill gas emissions using the NGER SWC: Mastering Landfill Emissions Package. This Package contains step-by-step instructions on estimating emissions.
The following is a checklist of information that councils should have on hand to use the NGERS SWC:
National Greenhouse Accounts (NGA)
National Greenhouse and Energy Reporting (NGER) Scheme
NGER Solid Waste Calculator (SWC)
Hunter Joint Organisation Mastering Landfill Emissions Package
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