The CO₂ report will only available for accounts of German companies for now and can be activated by request. To activate it, please contact our support team.

If the function is activated for you, users with the company-wide accountant role (accountants who are in the “Users outside the groups” group) can find the option under "Reports" > “CO₂” and can request the report for a configurable period either in PDF or CSV format.

You will then receive an email with a link from which you can download the summary of the CO₂ values. In order to open the link, you must be logged in to Circula for data protection reasons.

We work with our partner Lune to calculate the CO₂ values. They support us both technically and professionally in this area. Lune provides us with an API with an extensive database of emission factors.

Once you request the CO₂ report, the expenses and travel costs stored in Circula are sent to Lune's API. Only exported expenses and mileages are taken into account for the selected time period.

The entries are then matched against Lune's database using the category or merchant ID (for credit card spend). For example, the category "Bewirtung (Hospitality)" in Circula is matched with the corresponding category in Lune's catalogue, the same logic applies to mileages with a car or motorcycle. After matching, a corresponding calculation factor is assigned.

In the case of expenses, this factor is multiplied by the monetary value to obtain the CO₂ value:

For mileages, the factor is multiplied by the distance:

For expenses, Lune therefore estimates the purchase value at the time of the transaction and the product category, while the distance travelled and the means of transport are taken into account for mileages.

These calculations are based on the leading international standard for emissions calculations, the GHG Protocol. In addition, industry-specific methods are used to increase accuracy, e.g. ICAO for flights or GLEC for logistics. These estimates are designed to help companies understand their carbon footprint and take action to reduce their environmental impact.

The unit of the results is tCO₂e, which stands for metric tons of carbon dioxide equivalent. It is used to express the amount of greenhouse gases released in a way that standardizes the impact of different gases such as methane and nitrous oxide in relation to the amount of carbon dioxide that would have the same global warming potential.

This simplifies the comparison and aggregation of emissions data across different activities and sources. For smaller quantities of emissions, the unit can also be expressed in grams (gCO₂e) or kilograms (kgCO₂e).

The following inputs from Circula are taken into account for expenses:

The following inputs are taken into account for mileages:

The categories assigned to car and motorcycle trips in the calculation are based on average values.

Please note that Circula is not a specialized CO₂ analysis tool. The values provided are for rough guidance only and are intended to help our customers develop a better awareness of potential CO₂ emissions. A precise CO₂ balance can only be guaranteed by dedicated sustainability tools.

CO₂ emissions from corporate spending are traditionally one of the most difficult to calculate. Scope 3 emissions, indirect emissions related to a company's activities such as business travel, purchased goods and services, operational waste, account for 80-95% of a company's total emissions. So if companies have the opportunity to understand and address the majority of their emissions, it will help them reduce their emissions. By identifying areas of high emissions, companies can develop strategies to reduce their carbon footprint, improve efficiency and comply with emissions regulations.