Tools for carbon footprint calculation, what should be considered?

What should be considered when choosing tools for carbon footprint calculation? Before inputting the numbers and compiling the results, make sure at least the following aspects are taken into account.

As the year 2023 is approaching its end, companies are preparing to calculate the emissions of the past year for spring 2024 reporting. If carbon footprint calculation has not yet become a routine, or if you are calculating for the first time, perhaps for CSRD reporting, check at least the following aspects of your calculation tools.

Suitability of the carbon footprint calculator

Is the calculator designed for product or organizational carbon footprint calculation? Generally, the same calculator cannot be used for both without producing unreliable results. The calculator should also be based on well-known carbon footprint calculation standards. In organizational calculations, these are the Greenhouse Gas Protocol standards, and in product calculations, ISO 14067. Remember to include in your report information about the standard on which the calculation is based.

Accuracy of the carbon footprint calculator

Various free calculators for corporate carbon footprint can be found on the internet. Familiarize yourself with the background of the calculator: who created it and when was it last updated? Is the calculator developed and maintained by experts, or is it free of charge or perhaps prepared by former colleague years ago? Can you trust the accuracy and timeliness of the calculator? If the calculator has not been updated for several years, its emission factors are likely not up to date either.

Timeliness of emission factors

Where were the emission factors obtained? What is the year of reference? Ensure that the emission factors come from a reliable source, are up-to-date, and are suitable for your calculation. If, for example, the emission factors for electricity, district heating, and fuels are not from the previous year, bells should ring. Googling may yield various emission factors, some of which are old and from unreliable sources, with no description of their backgrounds. If in doubt, confirm the reliability of the emission factors with an expert or obtain them from a database admined by experts.

Report assumptions and uncertainties

If you notice uncertainties in the calculation or you have to make assumptions, report them. Carbon footprint calculation is rarely perfect. Almost every calculation involves uncertainties and assumptions. If this happens, do not give up, but openly communicate them. The reliability of the emission report can be further improved by third-party verification.

Continuous Improvement

The first calculation rounds are the most challenging. Often, emission data for the supply chain, for example, is difficult to obtain, reducing calculation accuracy. However, the process becomes easier year by year, and data becomes more precise. And when the tools are up to date, the task for the coming years is only to refine the initial data.