Measure & Verify
Learn about best practices for carbon accounting maturity
Your company's GHG footprint should be updated every year to track the evolution of the company's GHG emissions. This annual GHG inventory process involves different levels of updates, detailed in this section.
First, at each inventory cycle, activity data should be updated, as well as emission factors when relevant (e.g., using latest emissions factors to reflect average electricity mix in scope 2)
Second, best practice is to continuously improve your company accounting maturity, i.e., refining your calculations to be the most specific, granular as possible. This will be key to identify new opportunities of decarbonization, as well as reflecting the impact of decarbonization measures
Finally, in case of important changes, your company's previous GHG inventories may have to be recalculated for tracking or target setting purposes
At each inventory cycle, activity data should be updated to reflect activity levels of your company of the selected year of reporting (e.g. purchased volumes of fuels, electricity consumption, etc.)
Emission factors should also be updated regularly, especially the ones reflecting a market average such as grid emissions factors, air travel or end of life emissions factors which might vary significantly. Most third-party databases provide annual updates.
At each inventory cycle, the best practice is to improve accounting maturity by focusing on improving the granularity and quality of activity data and the corresponding emissions factors.
It is a continuous process to improve accounting maturity. It is common for companies to start with secondary or even proxy data, as accessing high-quality scope 3 data is often challenging during the first accounting effort. While your company should aim to meet best practices whenever possible, high maturity-level approaches often require more time and labor.
The most relevant approach for each category (or sometimes specific emission sources within a category) will then depend on the factors described below:
The relative size of the emissions categories
Your company’s business goals (e.g. on which categories is your company focusing its decarbonization efforts requiring specific performance tracking efforts)
Data availability (e.g., ability to retrieve supplier-specific data)
Data quality
GHG inventory data quality and the ability to track performance will depend upon on the quality of the data used to calculate emissions. Best practice is to collect as much primary and specific data as possible, particularly for relatively high emissions categories.
What is primary data vs secondary data?
Examples of primary and secondary data by scope 3 category
Sources of primary data and secondary data can vary in quality. Best practice is to select data that is the most representative in terms of technology, time, and geography; most complete; and most reliable.
What are the different levels of data specificity?
The level of specificity of the data highly impacts the overall quality of the data.
We can differentiate three main levels of specificity for activity data, mostly depending on the type of sources.
Similarly, there are different levels of specificity for emissions factors, which can be classified as the following:
