Greenhouse gas emissions and the NGER scheme

What is the NGER scheme?

The National Greenhouse and Energy Reporting (NGER) scheme is Australia’s national system for measuring and reporting greenhouse gas emissions and energy use. It was created by the National Greenhouse and Energy Reporting Act 2007 and is run by the Clean Energy Regulator. Each year, large companies that emit more than certain thresholds must measure their emissions using the official rules and report them to the government (Clean Energy Regulator, 2025).

The measurement rules live in a legal document called the NGER (Measurement) Determination 2008, which is updated every year. It lists an official emission factor for every fuel — coal, natural gas, petrol, diesel, LPG, firewood and dozens more — and for grid electricity in each state (Australian Government, 2025). The government also publishes a friendlier summary of these factors, the National Greenhouse Accounts Factors, for anyone who wants to estimate emissions outside formal reporting (Department of Climate Change, Energy, the Environment and Water [DCCEEW], 2025).

Scope 1 vs Scope 2 — where the emissions happen

Emissions are grouped by where they are physically released:

(There is also Scope 3 — emissions up and down your supply chain, like the fuel burned to deliver goods you buy. It matters, but it sits outside the basic NGER Scope 1 + 2 picture this site focuses on.)

What does “t CO₂-e” mean?

Burning fuel releases more than one greenhouse gas: carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O). Methane and nitrous oxide are far more powerful warmers than CO₂, so to add everything up fairly, each gas is converted into the amount of CO₂ that would cause the same warming. The result is expressed in tonnes of carbon dioxide equivalent (t CO₂-e). Under the current rules, 1 tonne of methane counts as 28 tonnes CO₂-e and 1 tonne of nitrous oxide counts as 265 tonnes CO₂-e (DCCEEW, 2025).

The calculation — simpler than it looks

For a fuel you burn (Scope 1), the official Method 1 formula is:

• Quantity — how much fuel you used (litres, tonnes, cubic metres…).
• Energy content factor — how much energy each unit of fuel holds, in gigajoules (GJ). Skipped if your bill is already in energy units (gas bills show megajoules).
• Emission factor — kilograms of CO₂-e released per GJ of that fuel, from the Determination. Dividing by 1,000 converts kilograms to tonnes.

Electricity — why your state matters

For grid electricity (Scope 2) the formula is even simpler: kWh × emission factor ÷ 1,000. But the factor depends on where you live, because each grid has a different mix of coal, gas, hydro, wind and solar (Australian Government, 2025):

Tasmania (mostly hydro) sits at 0.20 while Victoria (brown coal) is 0.78 — nearly four times higher. The same 5,000 kWh of yearly household electricity means about 1.0 t CO₂-e in Hobart but 3.9 t in Melbourne.