A carbon footprint is the total set of GHG (greenhouse gas) emissions caused directly and indirectly by an individual, organization, event or product. It is the measure of the environmental impact of a particular individual or organization’s lifestyle or operation. It is usually expressed in tonnes of carbon dioxide equivalent CO2-eq., which accounts for the different global warming effects of other greenhouse gases. The method used for calculating carbon footprints is life cycle assessment (LCA) which is also referred as the ‘cradle-to-grave’ approach. It takes into account energy inputs and emission outputs throughout the process or product.
In general, there are three types of carbon footprint: a) organisational carbon footprint, b) product carbon footprint (single product/activity/service), c) all activities and products through the supply chain. An organisational carbon footprint deals with the entire activities of organisation and it measures the GHG emissions from all the activities across the organisation, including energy used in buildings, industrial processes and vehicles. A product carbon footprint measures the GHG emissions over the whole life of a product (goods or services), from the extraction of raw materials and manufacturing right through its use and final re-use, recycling or disposal. Carbon footprint through the supply chain includes the GHG emissions right from the production of raw material until the usage of the product by the end user.
The carbon footprinting consist of three types of scopes. Direct emissions/scope 1 is the greenhouse gas emissions from sources that are owned or controlled by the reporting organisation. Indirect emissions/scope 2 is greenhouse gas emissions from imported power, electricity and heating or cooling. Scope 3 is an optional reporting category that allows for the treatment of all other indirect emissions.
The steps involved in carbon footprinting are as follows:
- Decision on the method/procedure/standard to be followed
- Identification of organisational and operational boundaries
- Collection of data
- Applying the emissions factors
- Verifying the results
- Device a strategy to reduce emission
- Verify the actions to reduce the emission
Carbon footprinting can be done for one time or can be repeated every year. But the initial CFP is kept as benchmark and CFPs thereafter are carried out to verify the results and the credibility of the actions taken to reduce the CFP from the previous year. The choice of the inventory boundary depends on the characteristics of the company, the intended purpose of information, and the needs of the users. The factors that should be considered when choosing an inventory boundary are organizational structures, operational boundaries and business context. Identification of organisational and operational boundary goes a long way in the successful conduct of a carbon footprint.
Reporting a minimum of scope 1 and scope 2 emissions is required for GHG protocol corporate standard and the ISO standards. A carbon footprint report based on GHG protocol corporate standards consists of a) Required Information and b) Optional Information. Required information is a public GHG emissions report that is in accordance with the GHG protocol corporate standard, which includes description of the company with inventory boundary and information on emissions. Optional information is a public GHG emissions report should include the following additional information (if applicable) such as information on emissions and performance and information on offsets.