Carbon Calculators – Western Australian example farms

Page last updated: Tuesday, 30 November 2021 - 8:10am

Agricultural practices and farming systems produce greenhouse gases (GHG) emissions. These emissions are mainly in the forms of methane and nitrous oxides. Baselining carbon accounts for individual farms will give total GHG emissions for the farm and the carbon intensity of crops and livestock produced.

The carbon accounts of four example farm enterprises in the WA agricultural region were calculated using a tool designed specifically for Australian producers. The example farms were:

  • Eastern Wheatbelt 100% cropping enterprise
  • Eastern Wheatbelt mixed grain and sheep enterprise
  • Geraldton Medium Rainfall 100% cropping enterprise
  • Woolbelt mixed sheep and grain enterprise

The data for these examples has been established using the 2019 Planfarm Benchmarks, along with expertise and advice from local agronomists and other industry professionals.

Farm baseline accounts include all emissions on farm, emissions from purchases and inputs such as fertiliser, feed, and electricity. These are classified as Scope 1, 2 and 3.

  • Scope 1: All emissions on-farm from agricultural activity
  • Scope 2: Emissions from the production of purchased electricity
  • Scope 3: All emissions associated with producing inputs such as fertilisers, herbicides, veterinary services etc.

It is best for individual farmers or consultants to go through the process of developing a baseline carbon account for their own individual farms to tailor the inputs to that specific enterprise. The quality of the results is dependent on the quality and detail of the data used, so accurate farm records are important.

The calculator used is the Greenhouse Accounting Framework (GAF). Using the Cropping GHG Accounting Framework (G-GAF), and the Sheep & Beef GHG Accounting Framework (SB-GAF). These tools were developed and maintained by Primary Industries Challenge Centre and the University of Melbourne.

These calculators use MS Excel spreadsheets and are freely available to download. The tools also align with the Australian National Greenhouse Gas Inventory (NGGI) method. They are simple, intuitive to use and utilise data that should be readily available for a farmer. These tools provide a snapshot of a single years GHG emissions, they report the emissions as carbon equivalents (CO2e) of Carbon Dioxide (CO2), Methane (CH4) and Nitrous Oxide (N2O).

The spreadsheets do require combining the livestock and cropping calculators results outside of the calculators themselves for mixed enterprises.

The tools are freely available to run your own farm here.

Summary of example farms

Comparing the different examples, farm emissions as well as the composition of those emissions can vary greatly. While the Woolbelt mixed farm was the smallest in hectares, it had the largest number of livestock in the system, and the livestock have largely contributed to the farms total emissions compared to the other farm examples. The Eastern Wheatbelt (EW) 100% cropping farm had the lowest total emissions, as it was the farm with the lowest intensity of fertiliser and had no livestock (Figure 1).

The emission intensity remained similar between cropping systems however it was higher in the Geraldton (GE) 100% cropping example (table 1).

Figure 1 – Comparison of the four different farming systems emission breakdowns.
Figure 1 Comparison of the four different farming systems emission breakdowns
Table 1 Emission intensities across four different farming systems
 

Wheat

Barley

Pulses

Oilseeds

Sheep Meat

Sheep Wool

 

t CO2-e/t crop

t CO2-e/t crop

t CO2-e/t crop

t CO2-e/t crop

kg CO2-e / kg LW

kg CO2-e / kg greasy

EW 100% Cropping

0.29

0.31

0.24

0.70

   

EW Mixed Farm

0.29

0.31

0.24

0.70

8.10

29.40

GE 100% Cropping

0.36

0.41

0.26

0.88

   

Woolbelt Mixed Farm

0.29

0.31

   

7.63

28.54

These farm examples provide some ballpark emission figures and compositions for different farm enterprises and locations. They are jumping off points for producers to then go and utilise their own farm and its systems to investigate their own carbon emissions.

More detail of the farm examples and emissions following.

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Contact information

Ashleigh Lydon
+61 (0)8 9081 3103
Mandy Curnow
+61 (0)8 9892 8422