Practical Tips for GHG Calculations

Kristen Haines

5 December 2024

Calculating greenhouse gas (GHG) emissions is a critical step in any sustainability journey. While the process can seem complex, there are key elements that you should focus on to make it a much more manageable process.

Here are some practical tips to help you build a reliable and accurate GHG inventory.

Accuracy of Activity Data

The foundation of any GHG calculation is activity data, which measures the level of activity contributing to emissions. Examples include litres of fuel used, kilometres travelled, or the amount of electricity consumed. The accuracy of this data directly affects the reliability of your emissions calculations.

Start with existing records: Fuel receipts, utility bills, or vehicle logbooks are often a good source.
Improve data collection: Over time, consider introducing systems like detailed vehicle logs or energy monitoring tools to capture data more precisely.
Match activity units: Ensure that your data aligns with the units required by your emissions factors for accurate calculations.

Source of Emissions Factors

Emissions factors are values that estimate the amount of GHG emissions per unit of activity. Selecting the right factors is crucial for producing meaningful results.

Prioritise reliable sources: Government databases, such as the Australian National Greenhouse Accounts factors are useful source.
Adjust for currency and time: If using spend-based factors, ensure they match your expenditure’s currency and year, adjusting for inflation if needed.
Check for relevance: If you are using international factors, consider whether the region that factor comes from is appropriately comparable to your facts and circumstances.

Key Considerations for Scope 3 Categories

Scope 3 emissions, which cover indirect activities in your value chain, are often the largest and most complex to calculate. Whilst some data can be extracted from your financial records, other areas will require further data collection to be able to form your GHG estimates.

Some specific considerations might include:

Purchased goods and services: Use spend-based calculations as a starting point and refine with more specific activity data for areas of significant emissions.
Business travel and employee commuting: Leverage existing travel records or employee surveys for initial data.
Waste: Collaborate with waste management suppliers for emissions details and focus on larger waste streams like landfill contributions. The good news is that it is considered that there are zero emissions when you recycle waste.

Selecting Carbon Accounting Software

Software can streamline GHG calculations, but it’s essential to choose a system that fits your needs.

Integration: Look for tools that work with your existing bookkeeping or financial systems.
Industry suitability: Some software packages are tailored for specific industries, offering greater accuracy and relevance.
Data requirements: Understand that even with software, significant manual data collection may still be required.

Treatment of Carbon Offsets

Carbon offsets can help balance out unavoidable emissions, but it’s important to use them appropriately.

Disclose gross emissions: Always report your total emissions before offsets. Offsets should appear as a separate line item in your reporting.
Avoid over-reliance: Focus on reducing emissions directly before turning to offsets as a supplementary measure.

Moving Forward

By paying close attention to activity data, emissions factors, and key Scope 3 categories, you can build a credible GHG inventory that supports your sustainability goals. Leveraging software and offsets strategically will further enhance your efforts.

For more information please view our webinar on tips and tricks, or contact your local Moore Australia advisor for more information on how we can assist you in implementing a GHG Accounting system.