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Everything you need to know about the Open Carbon API methodology

Greenly launches its API Carbon Index™ to assist companies, communities and citizens in their environmental efforts.

A bit of context... What is Open Carbon API™?

Open Carbon API is a tool to help companies, communities and citizens in their environmental and decarbonisation efforts.

Just as the Nutriti-Score helps consumers make informed food choices by displaying a score, accessible and understandable to all, based on the nutritional quality of food products, the Carbon Index aims to enlighten stakeholders on a company’s decarbonisation and environmental efforts.

The environmental quality of a company is predominantly based on three considerations:

  • Awareness of sustainability issues: understanding both the impact of the company on society and the environment, as well as the impact of society and the environment on the company.
  • Measuring and sharing the company's carbon footprint.
  • Implementing an environmental strategy: reducing its emissions by defining a trajectory in line with the objectives of the Paris agreements and implementing an action plan to achieve these climate objectives, engaging its employees and suppliers and, as a last resort, offsetting residual and unavoidable emissions.

Scope 3, which includes the indirect emissions (upstream and downstream) of companies excluding energy consumption (electricity, heat or steam) represents on average 80% of a company's total emissions. Reducing emissions and achieving decarbonisation objectives therefore requires understanding and controlling the entire value chain. This task is particularly complex and time-consuming.

The Carbon Index addresses this need by providing companies, communities and citizens with a tool to make responsible purchasing and informed supplier choices.

A transparent methodology and score

The first step is to collect the relevant company data. The majority of the information used will already be available directly on the company’s website or in company reports. Some data may also have been communicated directly by the company to Greenly via a questionnaire or extracted from ADEME, CDP or Greenly databases. Many companies will have already been processed and analysed by Greenly, however, the process is continuous and ongoing, which means the data is regularly updated and re-analysed to ensure that the score is as accurate as possible.

Next, a score must be calculated for as many companies as possible. Since the data for each company will vary in terms of nature and quality, in addition to establishing a transparent and fair methodology, it is crucial that this methodology allows us to differentiate between companies (from the unaware company to the most committed company) in a representative way while ensuring a large enough variance for the score to be meaningful.We therefore decided to classify the companies into seven categories, which are defined below.

The score is then established by following the decision tree below:

Limitations and areas for improvement

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The data and methodology are inherently imperfect. In order to calculate a score that is easily accessible and understandable by all, certain methodological and simplification choices had to be made. Additionally, some data may have been omitted. Finally, it’s important to note that in order to continually improve the Carbon Index, the methodology will also evolve; our expert teams continually work to improve its accuracy and any remark, correction and proposal for improvement will be studied and implemented.

If you think that an error has been made, please get in touch with us directly.
It is also important to note that the Carbon Index is different from the Greenly score.

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